Proceedings

IRE-1953-04
Proceedings
of the

APRIL ·1953
I' R'E

DIRECT DIGITAL DISP

11E RCA LABORAT(

,

APR I' 195 Industry Servic.

Volume 41

Number 4

IN THIS ISSUE Radio Progress During 1952 Admittance Diagrams in Oscillator Analysis IRE Standards on Sound Recording Reliability of Airborne Electronic Components Noise in aMicrowave Amplifier Characteristics of Picture Tubes Shaping and Filtering Networks Characteristics of Single-Layer Coils Abstracts and References

Berkeley Sctent:fic C1 ,1
Development of high-speed (to 1,000,000 cps) electronic counting units capable of displaying results in digital form permits use of direct-reading digital instruments for precise frequency measurement, interval timing, tachometry, measurement of pressure, temperature, flow, viscosity.

To order your 1953 Convention Record see page 554 for information.
TABLE OF CONTENTS, INDICATED BY BLACK-AND-W HITE MARGIN, FOLLOWS PAGE 64A

The IRE Standards on Sound,Recording and Reproducing: Methods of Measurement of Noie, 1953, appear in this issue.

The Institute of Radio Engineers

*(4,,.,,. for MINIATURIZED COMPONENTS

from STOCK

onst

· à

ry an. portab1e cv an gear has requ re au o

components of smaller and smaller dimension. This is particularly exaggerated in the case of

transformers for use in transistor circuits. The "H" series of miniature and sub-miniature units

escribed below are hermetic military types to cover virtually all audio applications. For

ven smaller structures our ultra-miniature types are available against quantity orders.

MINIATURE AUDIO UNITS...RCOF CASE

Typo No. H-1 H-2 H-3 H-4
H-5 H-6
H-7 H-8 H-9 H-10
H-11

Application
Mike, pickup, line to grid Mike to grid Single plate to single grid Single plate to single grid, DC in Pri. Single plate to P.P. grids Single plate to P.P. grids, DC in Pri. Single or P.P. plates to line Mixing and matching
82 41:1 input to grid 101 single plate to single grid Reactor

MIL Type
TF IAIOTY TF IA1 ITT TF1A15TY TF1A15TY

Pri. Imp. Ohms
50,200 CT, 500 CT' 82
15,000 15,000

Sec. Imp. Ohms
50,000 135,000
60,000 60,000

DC in

Response

Pri., MA · 2db. (CVc.)

o 50-10,000

50 250-8,000

o 50-10,000
200-10,000

Max. level List

dbm

Price

5 +21 + 6 +14

$16.50 16.00 13.50 13.50

TF1A15TY TF1A15TY

15,000 15,000

95,000 CT 95.000 split

O 50-10,000 4 200-10,000

+ 5 +11

15.50 16.00

TFIAI3TY TFIAI6TY TFIAlOYY TFIAI5TY

20,000 CT 150/600 150 600 10,000

150 600 600 CT 1 meg. 1 meg.

4 200-10,000 0 50-10,000 0 200-3,000 (4db.) O 200-3,000 (4db.)

+21
+ 8 +10 +10

16.50 15.50 16.50 15.00

TF1A2OTY

300 Henries-0 DC, 50 Henries-3 Ma. DC, 6,000 Ohms.

12.00

"Mai> ·
·

·

RCOF CASE

Length

125/64

·

Width

·

Height

61/64 1 13/32

·

Mounting

1 1/8

·

Screws

4-40 FIL.

·

Cutout

·

Unit Weight

7/8 Dia. 1.5 oz.

SM CASE

Length

11/16

Width

1/2

Height

29/32

Screw

4-40 FIL.

Unit Weight

8 on.

SUBMINIATURE AUDIO UNITS...SM CASE

Type No. H-30 H-31
H-32 H-33
H-34
H-35

Application
Input to grid Single plate to single grid, 3:1 Single plate to line Single plate to low impedance Single plate to low impedance Reactor

MIL Type
TFIAIOYY TF1A15TY

Pri. Imp. Ohms
50'· 10,000

Sec. Imp. Ohms
62,500 90,000

DC in Pri., MA

Response 2db. (Cyc.)

O 150-10,000 · O 300-10,000

TFIA13TY TFIAI3TY

10,000··· 30,000

TF1A13TY 100,000

200

3 300-10,000

50

1 300-10,000

60

.5 300-10,000

TF1A20YY

100 Henries-0 DC, 50 Henries-1 Ma. DC, 4,400 ohms.

Max. level List

dbm

Price

+13 +13

$13.00 13.00

+13 +15

13.00 13.00

+ 6

13.00

11.00

SfeeeUe'L4TtR.A-MINIATURE UNITS TO SPECIFICATIONS ONLY

UTC ultra-miniature units are uncased types of extremely small size. They are made to customers' specifications only, and represent the smallest production transformers in the world. The overall dimensions are 1/2 x1 /2 x ...Weight approximately .2 ounces. Typical special units of this size are noted below:

Type K-16949 Type M-14878 Type M-14879 Type M-14880 Type M-14881

100,000 ohms to 100 ohms...6 MW...100 to 5,000 cycles. 20,000 ohms (1 Ma. DC) to 35 ohms ... 6MW ...300 to 5,000 cycles. 6ohms to 10,000 ohms...6 MW...300 to 5,000 cycles. 30,000 ohms (.1 Ma. DC) to 3,000 ohms...6 MW...300 to 5,000 cycles. 25,000 ohms (.5 Ma. DC) to 1,000 ohms...6 MW...300 to 5,000 cycles. ·

TYPE UM

·200 ohm termination can be used for 150 ohms or 250 ohms, 500 ohm termination can be used for 600 ohms.
·· can be used with higher source impedances, with corresponding reduction in frequency range. With 200 ohm source, secondary impedance becomes 250,000 ohms ... loaded response is -4 db. at 300 cycles.
·· 'can be used for 500 ohm load ... 25,000 ohm primary impedance ... 1.5 Ma. DC.

150 VARICK STREET

·

NEW YORK 13 ., N. Y.

EXPORT DIVISION: 13 EAST 40th STREET, NEW YORK 16, N. Y.

C

ES: "ARLAIII"

3 Important Engineering Meetings

N

·

E

49 Exhibitors will display a widp line of the latest electronic proàucts. On a sense, no small part of the exhibit will be the campus of the University of Connecticut, which this meeting and Show haije

RCA LABORATORIES DIVISION
APR 13 1953

E

been moved after six years in B ton.
A detailed program can be obtained by writing Mr. A. Millard, Southern New England Telephone

Industry Service L NEW YORK

Saturday, April 11

Company, New Haven 6, Conn.

Storrs, Conn.
The New England Radio Engineering Meeting is staged by, and is intended primarily to meet the

Television
Saturday, April 18

needs of members of the North Atlantic Region, Institute of Radio Engineers. All engineers, scientists, educators, industrialists, students, and others interested in radio and allied fields, are cordially invited to take part in this one-day program of technical papers and exhibits of manufacturers' products, dealing with the broad field of electronics and radio engineering.
Registration should be made in advance, on or before April 4, 1953.
Technical Papers have been arranged to cover every field of radio, in two sessions, morning and afternoon, starting at 10 A.M. and ending at about 5P.M. Briefly, the subjects are:
Extraneous Disturbances in Servomechanisms

Cincinnati, Ohio
This meeting is jointly sponsored by the Cincinnati Section of the IRE, and the Professional Group on Broadcast and TV Receivers. Annually, a Saturday Meeting, held in the attractive Cincinnati Engineering Club Building, the morning session is comprised of five papers and the afternoon session four papers. All are on Television, and the afternoon papers feature color television exclusively.
Due to the facilities available, the exhibits are limited to television components and test equipment.
Mr. J. W. McRae, President of the IRE will be the principal Banquet Speaker.

May 11, 12, 13
Wednesday, Thursday, Friday
Dayton, Ohio
Airborne Electronics
Now an annual event of national interest, this meeting is jointly sponsored by the Dayton Section or the IRE and the Professional Group on Airborne Electronics.
The exhibits are extensive and occupy several floors of the Hotel Biltmore. The meeting takes three days and includes two luncheons and a Banquet.
The technical sessions include as subjects: Components, Propagation, Human Engineering, Elec-

Good Hearing in Auditoriums Health Physics Survey at the Cos-
matron

Engineering Club Building, Cincinnati, Ohio

tronic Instrumentation, Antennas, Vacuum Tube, Microwave, Production Techniques, Servo Analysis,

Propagation Discoveries, Their Lessons

Dielectrics, Circuits, Communications, Analog Computers, Transis-

Compatible Color Television TD-2 Microwave Radio Relay Sys-
tems North Atlantic Region Meeting.

tors, Network Analysis, Navigation, Measurements, Reliability; in fact every phase of radio-electronics as it applies in aviation.

The Luncheon talk is: "Electronics, A Challenger to Space and Time," by Daniel E. Noble.

A detailed program may be obtained from Mr. Peter R. Murphy, 121 Castle Drive, Dayton, Ohio.

IRE Meetings and Exhibits Speed Electronic Progress!
PROCEEDINGS tie THE I.R.E. April, 1953, Vol. 41, No. 4. Published monthly by the Institute of Radio Engineers, Inc., at 1 East 79 Street, New York 21, N.Y. Price per copy: members of the Institute of Radio Engineers $1.00: non-members $2.25. Yearly subscription price: to members $9.00; to nonmembers in United States, Canada and U.S. Possessions $18.00; to non-members in foreign countries $19.00. Entered as second class matter, October 26, 1927, at the post office at Menasha, Wisconsin, under the act of March 3, 1879. Acceptance for mailing at a special rate of postage is provided for in the act of February 28, 1925, embodied in Paragraph 4, Section 412, h'. I.. and R., authorized October 26, 1927.
Table of Contents will be found following page 64A

"APC" "VU"
is

Meetings with Exhibits
· As a service both to Members and the industry, we will endeavor to record in this column each month those meetings of IRE, its sections and professional groups which include exhibits.

ohm aó ane ete eurizei_ Put in HAMMARLUND CAPACITORS
Consider these facts about Hammarlund Capacitors when selecting components for your electronic equipment: · Plates are of brass, and soldered, not staked, to their supports to insure perfect contact and prevent loosening.
· Precision soldering fixtures and assembly jigs used during fabrication assure uniformity of plate spacing. · Rotor and stator assemblies are nickelplated to minimize corrosion. · Rotor contact springs are beryllium copper or phosphor bronze, and nickel or silver plated, for positive contact. These are some of the features that make Hammarlund Capacitors your best choice for use in quality electronic equipment.
HAMMARLUND
HAMMARLUND MANUFACTURING CO., INC. 460 WEST 34th ST. · NEW YORK 1, N. Y.
"MC"
.a

April 11, 1953 NEREM--New England Radio Engineering Meeting, University of Connecticut, Storrs, Conn.
Exhibits: H. W. Sundius, The Southern New England Tel. Co., 227 Church St., New Haven, Conn.
April 18, 1953 Spring Technical Conference of the Cincinnati Section, Cincinnati, Ohio
Exhibits: R. H. Lehman, The Baldwin Co., 1801 Gilbert Ave., Cincinnati 2, Ohio
May 11, 12 & 13, 1953 National Conference on Airborne Electronics Hotel Biltmore, Dayton. Ohio.
Exhibits: Paul Clark, 120 West Second St., Dayton 2, Ohio.
a
August 19, 20, 21, 1953 1953 Western Electronics Show and Convention, Civic Auditorium, San Francisco, Calif.
Exhibits: Heckert Parker, 1355 Market St., San Francisco 3, Calif.
September 21, 22, 23, 24 & 25. 195:: Eighth National Instrument Conference and Exhibit. Hotel Sherman. Chicago, Ill.
Exhibits: Richard Rimbach. 921 Ridge Ave., Pittsburgh 12, Pa.
a
September 28, 29 & 30, 1953 National Electronic Conferrm Hotel Sherman, Chicago.
Exhibits: Orville Thompson, c/o DeForrest's Training Inc., 2735 N. Ashland Ave., Chicago 14, III.

"RMC"

PROCEEDINGS OF THE I.R.E.

Apr 195

PROKAR®miniature molded CAPACIT RS now all rated for operation at

N EW processing iievelopments now make it possible for every Prokar miniature molded capacitor to De used at temperatures up to 125 °C without voltage derating! An exclusive Sprague solid dielectric and a mineral-filled phenol cjacket assure stable performance from -- 55 °C to +125 °C. Ten mold sizes--ranging upwards from the .175" dia. x 5/8t1 long unit pictured actual size at left--give you maximum space economy in miniaturized equipments. Originally developed for militaly uses, the moderate prices of these minia ture capacitors make them well worth your investigation also for use in dependable commercial electronic equipment. Write today for Engineering Bulletin 205F to the Sprague Electric Company, 235Marshall St., North Adams, Massachusetts.

WORLD'S LARGEST CAPACITOR MANUFACTURER

EXPORT FOR THE AMERICAS: SPRAGUE ELECTRIC INTERNATIONAL LTD., NORTH ADAMS, MASS.

CABLE: SPREXINT

PROCEEDI.VGS OF THE I.R.E.

April, 1953

3A

A Transistor of point-contact type. Two hair-thin wires control current flow in germanium nietal.

It's helping to win the Battle of the Watts

When you keep down the power needed to send voices by telephone you keep down the special equipment needed to supply that power. A great new power saver for telephony is the Transistor, invented at Bell Telephone Laboratories, and now entering telephone service for the first time.
Tiny, simple and rugged, the Transistor can do many of the things the vacuum tube can do, but it is not avacuum tube. It works on an entirely new principle and uses much less power than even the smallest tubes. This will mean smaller and cheaper power equipment, and the use of Transistors at many points in the telephone system where other equipment has not been able to do the job as economically.
It's another example of how Bell Telephone Laboratories makes basic discoveries, then applies them to improve telephone service while helping to keep its cost down.

Laboratories engineer examines Transistor oscillator. It is
used in Englewood, New Jersey, where 10,000 subscribers can personally dial distant cities. Transistors generate the signals which carry the dialed numbers to other towns and cities. Other uses are in prospect.

TRANSISTOR FACTS
Created by Bell scientists. First announced in 1948.
Has no glass bulb, requires no filament current or warm-up period. Operates instantly when called upon. Uses no energy when idle.

BELL TELEPHONE LABORATORIES
Improving telephone service for America provides careers for creative men in scientific and technical fields.

WRITE FOR FREE SAMPLES AND
CATALOG ON YOUR FIRM'S LETTERHEAD

CM-15 El Menco Capacitors range from 2 to 420 mmf. at 500 yDCw ...measure only 9/32" x 1 /2 "
x 3/16" ... but they're
PRETESTED at 1000V!
ALL fixed mica El Menco Capacitors are factory-tested at double their working voltage. So, you can be sure they'll stand up. They also meet all significant JAN -C-5 specifications. This means that you can specify them with confidence for all military or civilian electronic applications.

Our Type CM-15 silvered mica capacitors reach 525 mmf. at 300 vDCw. Our other types -- silvered and regular -- provide capaci-
ties up to 10,000 mmf. Want samples for testing? The Electro illotive Manufacturing Co., Inc., Willimantic, Contr.

MOLDED MICA

Jobbers and distributors are requested to write for information to Arco Electronics, Inc., 103 Lafayette St., New York, N. Y. -- Sole Agent for Jobbers and Distributors in U. S. and Canada.
12111.COmic. TRIMMER
CAPACITORS

Foreign and Electronic Manufacturers Get Information Direct from our Export Dept. at Willimantic, Conn.

THE ELECTRO MOTIVE MFG. CO., INC.

WILLIMANTIC, CONNECTICUT

PROCEEDINGS OF THE I.R.E.

April, 1953

5A

IN »WE-WOUND CORES
JUST NAME YOUR REQUIREMENTS!

RANGE OF MATERIALS Depending upon the specific
properties required by the application, Arnold Tape-Wound Cores are available made of DELTAMAX
..4-79 MO-PERMALLOY ... .SUPERMALLOY ..MUMETAL
.4750 ELECTRICAL METAL... or SILECTRON (grain-oriented silicon steel).
RANGE OF SIZES Practically any size Tape-Wound
Core can be supplied, from afraction of a gram to several hundred pounds in weight. Toroidal cores are made in twenty-two standard sizes with protective nylon cases. Special sizes of toroidal cores--and all cut cores, square or rectangular

cores--are manufactured to meet your individual requirements.
RANGE OF TYPES In each of the magnetic materials
named, Arnold Tape-Wound Cores are produced in the following standard tape thicknesses: .012", .008", .004'1,.002", .001", .0005", or .00025", as required.

Áppseete f-ree
Let us help with your problems of cores for Magnetic Amplifiers, Pulse Transformers, Current Transformers, Wide-Band Transformers, Non-Linear Retard Coils, Peaking Strips, Reactors, etc.
Address: ENG. DEPT. P

WISE, 4613
PEARNOLD ENGINEERING COMPANY
SUBSIDIARY OF ALLEGHENY LUDLUM STEEL CORPORATION
General Office & Plant: Marengo, Illinois DISTRICT SALES OFFICES
New York: Empire State Bldg. Los Angeles: 3450 Wilshire Blvd.

6.`

Et,
\,
irtb eaddetee 7fer_RADIO TELEVISION UHF CIRCUITS TRONI $1. ELECTRICAL ANliFACIURING

'FULLY CONFORMS TO I* - 'REQUIREMENTS OF GRADE (.6A IN ACCORDANCE WITH JAN-I.lei
GENERAL
TITE, TITAHATES, ZIRCON

Pressed and Extruded Shapes to
Close Tolerances
Engineered Steatite by General Ceramics offers the designer and engineer both excellent electrical and mechanical advantages and the economies of standard catalog body types. Offers low loss factor, zero moisture absorption, high surface and volume resistivity, high tensile and great compressive strength. Steatite insulators can be produced to countless sizes and shapes for practically all requirements.

Standard Shapes AVAILABLE:
PILLAR INSULATORS LEAD-IN BUSHINGS ENTRANCE BUSHINGS
COAXIAL CABLE INSULATORS
LEAD-IN INSULATORS SPREADER INSULATORS
STRAIN INSULATORS COIL FORMS
SUPPORT BARS COUPLING INSULATORS

"STEATITE-BONDED-TOMEIM." COMBINATIONS
Steatite bonded to metal by the Solder-Seal method produces o permanent hermetic seal. Also recommended for re-inforcing steatite where ex-
ceptional mechanical strength

FOR UHF CIRCUITS, SPECIAL G-C STEATITE
General Ceramics Special Steatite developed for UtiF service. An engineered insulation with extremely low loss factor. Recommendations
made on specific applications
without obligation.

CUSTOM DESIGNS 10 SPECIFICATION --
Special steatite insulatosirzsecoon,
be produced in .any hope by pressing, extrydsing, casting or .machining. Experienced engineers are
available for consultation.

is required.

IF YOU HAVE A PROBLEM --
For complete information on General Ceramics Steatite Insulators, request the new illustrated catalog; foi engineering assistance on specific problems, contact aGeneral Ceramics Sales Engineer.

CERAMICS and STEATITE CORP. Perth Amboy 4-5100 GENERAL OFFICES and PLANT: KEASBEY, NEW JERSEY LAIN, FERRAMICS, EIGHT DUTY REFRACTORIES, CHEMICAL STONEWARE. IMPERVIOUS GRAPHITE AND FERRAMIC MAGNETIC (ORES

PROCEEDINGS OF THE I.R.E.

April, 19.5.;

7.\

need

la1i 114s ) h
8A

FOR DEPENDABLE

ELECTRICAL CONTROL

Again and again, these rugged, vitreous-enameled wire-wound Ohmite resistors have demonstrated their ability to provide
unfailing performance and long life under the most difficult service conditions.
Ohmite also offers the most complete line of wire-wound resistors on the market ...fixed, tapped, adjustable, non-induc-
tive, and precision units--in more than 60 wattage sizes ranging from 1" to 20" in length, in 18 types of terminals and
in a wide range of resistance values. Investigate Ohmite resistors for your product.

Ohmite vitreousenameled resistors are available from stock or promptly made to order in a
wide range of sizes and types.

Write on company letterhead for complete catalog. Ohmite Manufacturing Co., 4860 Flournoy St., Chicago 44,

liàee- IN WIRE-WOUND RHEOSTATS AND RESISTORS

PROCEEDINGS OF THE I.R.E.

April, 195:

Microwave power input.
Microwave power transmitted with negligible atten-
uation. Microwave power 9reue,,this direction attenuated more
than 20 DB.
Improves stability of source, (By isolation). Eliminates reflection from loads. Eliminates reflection from detector with essentially no loss in sensitivity. Eliminates pulling due to wavemeter. Gives good broad-band match.
Avaiimlambedldeeilraiovteeery * Additional Frequency ranges will soon be available.

UNIDIRECTIONAL TRANSMISSION LINE Now available for higher frequencies
The Uniline section is a new development specifically designed for use in test measurements particularly where the impedance of the load is variable. For example, one of the several possible applications for the Uniline is as a replacement for the loss-type attenuator commonly used for isolation between source and load. In this instance, very substantial isolation is provided with negligible loss in transmitted power. Up to 100 times as much power is available for test purposes when the Uniline is used. The Uniline is a truly non-reciprocal transmission line element, not a directional coupler.
TYPICAL CHARACTERISTICS:
Frequency range: 8800-9600 megacycles. 9600-10,400 megacycles.
Wave guide size: 12"x1"x6' 2"
Attenuation in forward direction: Less than 1 DB.
Attenuation in reverse direction: 20 DB (approx.)
Voltage standing wave ratio: 1.3:1 (or less) either direction.
Finished with standard flat flange unless specified.
Write for descriptive bulletin which gives theoretical and operational details.

CASCAD R SEARCH
o
Victory Lane Los Gatos, California

PROCEEDINGS OF THE I.R.E.

April, 19.53

9A

The art of cutting jewels is a thing of consummate skill and delicate touch. Gem cutting requires great accuracy.
But even gem cutting is not so precise or exacting as crystal processing by Midland's methods. As a result, you get the finest quality and highest accuracy scientific skill can produce in a frequency control crystal.
Midland Crystal Processing operations in many respects exceed the requirements of gem-cutting. Raw quartz is selected with regard to high electrical quality ...proceeds through slicing, lapping, etching; and the final plating and sealing corresponds to setting a jewel. And at every step Midland's critical inspection and test procedures are applied, including precise angular control by X-ray.
Your Midland crystal is a gem of stability, accuracy, high output, long life. Whatever may be your requirements for better crystal performance, you'll get them in fullest measure from Midland.

ktliget

&í ied C,Ow-eiKUltat di

414kitWtkiiaetivailkt,

WORLD'S

MANUFACTURING COMPANY, INC.
3155 Fiberglas Road · Kansas City, Kansas

LARGEST

PRODUCER

OF

QUARTZ

CRYSTALS

PROCEEDINGS OF TI IF TY F.

-.7or ",)%-ceilence in erlorrnance .

·

·

PYRAMID subinin hit tire
"GLASSEAL"
CAPACITORS
For the most demanding applications, where top-quality and minimum-size considerations are the most vital factors, Pyramid "Glasseal" capacitors are the popular choice.

This attractive new catalog PG-3, incorporating complete engineering data, styles, sizes, and capacitance and voltage ranges is now available.
°. Capacitance Change vs. Temperature

Power Factor vs. Temperature Curve

These graphs show typical performance characteristic! of the Pyramid "Glasseal X" type, which is designec
for 125 C. operation. Full information on all "Glasseal capacitors is provided in new catalog PG-3.

Visit Booth 2- 310

1. R. E. Convention

For your free copy, please address letterhead request to Department FI

PYRAMID ELECTRIC COMPANY

· · ·e

nallirsee11·1

0/1111 CI./ A D

b. I

··· · ·

TRIODES
2C39A 3W5C00A3 3W5000F3 3W1 0000A3 3X2500A3 382500E3 3X3000A1 3X3000F1 6C2I 25T 351 35TG 75TH 7STL 100TH

10On 152TH 152T1 250TH 25011 304TH 304T1 450TH 45011 592/3-200A3 750T1. 1000T 15001 20001

TETRODES
4-65A 4-125A 4-250A 4-400A 4-1000A 41,1160A

4W20000A 4X1 50A 4X150D 4X150G 4X500A 4X500F

PENTODE
4E27A /5-1258

RECTIFIERS
2-01C 2.-25A 2-50A 2-150D 2-240A 2-2000A KY2I A

RX2I A 2504 253 866A 872A 8020 110011

follow the leaders to

EINIAC TUBES!

4-125A
The radial-beam power tetrode that made transmitting screen-grid tubes popular. This tube will take a plate input of 500 watts for CW or 380 watts for fone. Driving power is less than two watts. A pair of these tetrodes make an ideal high power fone or CW final for the amateur.

4X150A
This small external anode radial-beam power tetrode operates efficiently at all frequencies into the UHF range with a driving power of only a few watts. Its small size and ruggedness make it ideal for compact equipment such as mo. bile.

AIR SYSTEM SOCKETS
4-400A /4000 4-400A 4006* 4.1000A 4000 4-1000A 4006* 4X150A 4000 4X1 50A 4006*
*Replacement Chimneys

VACUUM SWITCH

VS-2 13V Coil 24V Coil

ACCESSORIES
HR Heat dissipating connectors Preformed Contact Finger Stock

VACUUM PUMP
HV-1 041 DIFFUSION PUMP
PTYuPm·pAOil 14V-1 Pump Parts

VARIABLE VACUUM CAPACITORS
VVC60-70 VVC2-60-20 VVC4-60-20
ION GAUGE
100 IG ion gauge

450T
Often referred to as the workhorse of modern communication systems, this dependable triode has a plate dissipation rating of 450 watts. It is widely used as an amplifier, oscillator or modulator.

3K20000L
(A-F-K)
These Klystrons. the latest development in UHF television transmitting, have a power output of 5000 watts. The three versions of the Klystron will cover the entire UHF range --470-890 mc. These water and air cooled Klystrons have apower gain of 20 db.

VVC60-20
This is but one type in the Eimac line of variable and fixed vacuum capacitors for plate tank circuits. It is variable over arange of 10 mmfd to 60 mmfd. Maximum rf voltage is 20 kv. at 40 amperes.

2C39A
This small, rugged tri. ode is designed for use as a power amplifier, oscillator or frequency multiplier to frequencies above 2500 mc. It is particularly suitable for compact fixed or mobile equipment.

oComplete technical data
available on request.

VACUUM CAPACITORS

VC6-20 VC6-32 VC I2-20 VC12-32

VC2S-20 VC25-32 VC50-20 VC50-32

EITEL-McCULLOUGH, INC.
SAN BRUNO, CALIFORNIA

EXPORT AGENTS: FRAZA'R 8. HANSEN · 301 CLAY STREET · SAN FRANCISCO 11, CALIFORNIA

12\

PROCEEDINGS OF THE I.R.E.

April, 1953

HUGHES SETS NEW STANDARDS OF DIODE CONDUCTANCE

hermetically sealed in glass for electrical stability

HUGHES NOW OFFERS for commercial application eight new RTMA germanium diode types equivalent in every respect to Hughes regular subminiature types--and in addition carrying forward current minima of 10 ma. and 20 ma. at +1 volt!
THESE HIGH-CONDUCTANCE HUGHES DIODES, a product of Hughes pioneer research in semiconductors, provide better combinations of high peak inverse voltage, high back resistance and low forward resistance than have ever before been available in production quantities. Volume orders for these new types can be filled from stock.

HUGHES GERMANIUM DIODES have proved consistently able to meet exacting requirements in airborne electronic equipment for navigation, fire control, and guided missiles. Besides having the advantages of germanium diodes over vacuum tubes, H UGHES D IODES alone are

HUGHES GERMANIUM DIODE ELECTRICAL SPECIFICATIONS AT 25' C.

Description
HPiegakh Hi gh Back Resistance BHiagckh Resistance Hi gh Back Resistance PGuernperoasle
JAN Types

RTMA Type
1N558 1N68A 1N67A IN99 1N100 1N89 1N97 1N98 1N116 1N117 1N118 1N90 1N95 1N96 1N126" 1N1277
1N128T

Test Maximum Minimum

Peak Inverse Forward

Inverse Voltage*

WVoorlktiagneg

Current @ +1 v

(volts) (volts) (ma)

190 150

5.0

130 100

3.0

100

80

4.0

100

80 10.0

100

80 20.0

100

80

3.5

100

80

10.0

100

80 20.0

75

60

5.0

75

60

10.0

75

60 20.0

75

60

5.0

75

60 10.0

75

60 20.0

75

60

5.0

125 100

3.0

50

40

3.0

Maximum Inverse Current (ma)

0.500 0.625

eg--115000

v ,,

o.00s@ --5 v; 0.050 @ --50 v

g 0.005 g --5 0: 0.050 g --50 v
0.005 --5 v; 0.050 g --50

g-5 0.008 @I --5 v; 0.100 @ --50 v

0.008

v; 0.100 g --50 v

0.008 t -5 v; 0.100g --50 v

o.too 0.100

@e1--55000v

o.loo 0.800

e6---5500

Y v

t 0.800 g-50 v
0.800 -50 v

0.050 @ --10 0; 0.850 @ --50 v

0.025 t -10 v; 0.300g --50 v

0.010 g --10 v

That voltage at which dynam'c resistance is zero under spe ified conditions. Each Hughes Diode is subjected to avoltage rising linearly at 90 volts per second.

"Formerly 1N69A..

:Formerly 1N70A.

:Formerly 1N81A.

Ne , e;Ces In red.

each HUMIDITY-CYCLED each TEMPERATURE-CYCLED each JAN SHOCK-TESTED HUGHES DIODES are also supplied to special customer specifications, including high temperature electrical requirements.
Address inquiries to Dept. PR
SEMICONDUCTOR SALES DEPARTMENT
HUGHES
Aircraft Company Culver City, California

PROCEEDINGS OF THE I.R.E.

April, 1953

l3A

Selected stock. Always free from defects and surface blemishes.
Moisture and fungus proof coatings, varnish or lacquer smoothly applied. No wrinkles or unsightly heavy deposits.
C.T.C. standard terminals. Types for all applications. Silverplated, cadmium plated, elec. tro tinned, hot tinned or gold plated as required.
Precisely located, clearly defined imprinting: rubber stamped, silk-screened, en. graved or hot stamped.

Riveting or stoking of terminals, brackets and other components accomplished without radial cracks or splitting of rivet shanks, and without damaging the finish.
Cleanly cut or punched edges and holes. No signs of delamination.
Little details on terminal boards ...make the big difference in quality

C.T.C. is constantly supplying
special terminal boards to the top names in electronics. These boards are built to strict government specifications, are fabricated of certified materials to fit the job. Among the specifications involved are: MIL-P-
3115A, MIL-P-15037, MIL-P-15035,
MIL-P-15047, MIL-P-997A.
Our Custom Engineering Service is well-equipped to fill these specifications for you. We are thoroughly familiar with the JAN and MIL. approved materials and finishes in accepted usage by government agencies and the armed forces. This, combined with assembly know-how developed over many years of sup-
plying electronic components and equipment to the government, enables us to meet your needs for

quality above and beyond the basic government standards.
Boards can be made of cloth, paper, nylon or glass laminates (phenolic, melamine or silicone resin), and can be lacquered or varnished to specifications: JAN-C-173, MIL-V-173 and JAN-T-152. Lettering and numbering is done by rubber stamping, silk screening, hot stamp-

ing, engraving. Inks used in rubber stamping contain anti-fungus and fluorescent additives.
For complete information write: Cambridge Thermionic Corporation, 456 Concord Avenue, Cambridge 38, Mass. West Coast manufacturers, contact: E.V. Roberts, 5068 W.Wash. Blvd., Los Angeles, or 988 Market St., San Francisco, Cal.

CAMBRIDGE THERMIONIC CORPORATION

custom or standard.., the guaranteed components

14A

PROCEEDINGS OF THE I.R.E.

April. 1953

FO U1=Z

ITTEPZ./-

111 Accommodates up to four individual R. F. channels available in the following frequency ranges: 125-525 k/c, 2-18 m/c,118-132 m/c.
· Power output 400 watts LF and HF, 250 watts VHF.
· Accessibility of channels provides for easy inspection and maintenance.
· Single or simultaneous frequency transmission provides ultimate flexibility.
· Complete remote control operation.

Write today

for co

specifications.

ELECTRIC COMPANY, INC.
Fourteenth and Chestnut Kansas City 27, Missouri, U.S.A.

"Miniature" l-T-E precision wire-wound resistor -- 11/8" long x3/u" OD.

SIZE FORM
and
MUM

16A

"Meter multiplier" 915/32" long, ferrule type--houses four l-T-E precision resistors wound on bobbins of the same material as the encapsulation. This assures uniform low coefficient of expansion throughout the resistor resulting in a true hermetic seal.

PROCEEDINGS OF THE I.R.E.

April, 1953

I-T-E precision wire-wound resistors can be specially engineered to your requirements

New electronic equipment designs often require special types of precision wirewound resistors. A wide range of special types and ratings, built to exact customer specifications, is being produced by I-T-E in quantity.

Expanded I-T-E design and engineering facilities, and advanced production and testing techniques, are all combined to provide individually tested units guaranteed to perform within narrowly defined limits.

Here's what I-T-E offers you:

SIZE
Resistance values up to 500,000 ohms can be produced in abody as small as 1%" long x 346" OD--with emphasis on close accuracy, low temperature-coefficient, and high stability.
I-T-E also produces multiple-tapped units in cylindrical and card forms--or in any required special form. Number and spacing of taps are available to specification.
RESISTANCE
Special resistors are obtainable in tolerances down to ± 0.05%. I-T-E units surpass MIL-R-93A specifications.
Tiny plastic bobbins are used to obtain higher resistance values than ceramic-core resistors in the same size body.
Matched pairs can be supplied in any ratio--with ratio tolerance to within ±0.05%. (Unity ratio to within ±0.005%.)

FREQUENCY
Proper selection of wire and balanced winding techniques limit reactance within narrow ranges.
TEMPERATURE COEFFICIENT
I-T-E selects low temperature-coefficient resistance wire. Test procedures determine temperature coefficient of aprecision wirewound resistor to within ± 2 parts/ million/degree C. In matched pairs, TC of one resistor can be matched to TC of the other within ± 5 parts/million/degree C.
Rigid testing of each resistor makes it possible to guarantee TC of an entire lot.
STABILITY
Accelerated aging of finished resistors obtains stability as low as 0.005%. Hermetic sealing protects against the destructive effects of salt water immersion and high humidity.

WHAT ARE YOUR REQUIREMENTS ?
I-T-E engineering and production facilities offer you much more than a standard line of precision wirewound resistors and other wire-wound components. If your problem is special, write us outlining your requirements. Resistor Division, I-T-E Circuit Breaker Co., 1924 Hamilton St., Philadelphia 30, Pa.
PRECISION WIRE-WOUND RESISTORS

PROCEEDINGS OF THE I.R.E.

April, 1953

17 \

keeping communications ON THE BEAM

'r

JK STABILIZED JKO-2 OVEN
CRYSTALS FOR THE CRITICAL
The JKO-2 oven provides the fast warm up needed for two way mobile communication -- such as used in railroads, taxis, etc. Unit holds two JK H-17 type crystals, is compact, light weight. Crystals sealed against dirt and moisture. A stabilized heat unit, one of many JK products made to serve every need.
Ame,,ge t7i;
ttakes split second timing to maintain safe, "on the dot" ailroad schedules, and the traffic control involved is highly complicated. Today, railroads rely on radio to help keep lines unsnarled and traffic moving. JK Crystals in railroad communication equipment helps keep your train on time, every time.
FREQUENCY 8t MODULATION MONITOR Monitors any four frequencies anywhere between 25 mc and 175 mc, checking both frequency and amount of modulation. Keeps the "beam" on allocation / guarantees more solid coverage, tool the JK FD-12

.

18A

PROCEEDINGS OF TIIE I.R.E.

April, 1953

TUNG-SOL'S STATISTICAL QUALITY CONTROL METHODS produce tubes of unsurpassed reliability
Tung-Sol makes All-Glass Sealed Beam Lamps, Miniature-Lamps, Signal Flashers, Picture Tubes, Radio, TV and Special Purpose Electron Tubes.
TUNG-SOL ELECTRIC INC. Newark 4, N. J.
Sales Offices: Atlanta, Chicago, Culver City (Los Angeles), Dallas, Denver, Detroit, Newark, Seattle

For Transistor Applications

Mallory Mercury Batteries provide a constant voltage power supply

Nlallory Mercury Batteries are especially well suited for transistor power requirements. They deliver constant voltage and constant current... an absolute necessity for the best performance of transistor circuits. In addition, they will not deteriorate or lose their energy during long periods of storage ... even under the most adverse climatic conditions. Their high ratio of.energy to size and weight permits miniaturization of electronic equipment.
New transistor hearing aids are agood example of the substantial size reduction and operating economy that can he accomplished by using Mallory Mercury Batteries and tiny new Mallory Capacitors.
If you are designing equipment around transistor circuits, our engineers will be glad to work with Vou in

selecting a power supply to meet your requirements. Multi-cell packs and stacks are available for applications requiring greater capacity or higher voltages than provided by asingle cell. Various combinations can be built for virtually any capacity or space requirement. Write us todas for more information.
Use Mallory Mercury Batteries for applications where: ·Constant voltage or current is required ·Size and weight are important ·Long storage periods are involved ·Battery leakage cannot he tolerated ·Wide temperature and pressure ranges
are encountered .Severe impact and shock are expected

MALLORY P. R. MALLORY 8. CO.. Inc.

SERVING INDUSTRY WITH THESE PRODUCTS:
Electromechanical-- Resistors · Switches · Television Tuners · Vibrators Electrochemical--Capacitors · Rectifiers · Mercury Batteries

Metallurgical--Contacts ·Special Metals and Ceramics. Welding Materials

20A

PROCEEDINGS OF THE I.R.E.

April, 1953

THESE NEW GUARDIAN RELAYS PROVIDE
MORE POWER FOR ANY COMMUNICATIONS SYSTEM

Analyze the power increasing, space and weight saving features of Guardian's latest Series 595-P and 695-P Communications Relays ...features that have created an increased demand for these already popular favorites: (1). New, improved field piece has enlarged end adjacent to the armature which reduces magnetic reluctance of the hinge gap. (2). Armature pivots on a stainless steel pin bearing, resulting in minimum friction and maximum utilization of available power. (3). Magnetic circuit efficiency is assured by use of the correct combination of winding to core size for sensitive or power types.
The Series 595-P D.C. will carry up to 4 pole, double throw contact combinations. Weight of unit (double pole, double throw)-2.5 ounces. The Series 695-P D.C. will
carry up to 6 pole, double throw contact combinations. Weight of unit (double pole, double throw)-3.5 ounces. Both the 595-P and the 695-P are available hermetically sealed to meet Government specifications MIL-R-6106.

stgE D lû f Nr·
oc

,\

gm,

"t"

·

A

Y -7

*, 1.0 -4'

!

Series
595 -P D. C. RELAY

-eve
AN-3303-1 WRITE --WIRE --TELITY PE-- PHONE NOW!

GUARDIAN ELECTRIC

1628-D W. WALNUT STREET

CHICAGO 12, ILLINOIS

A COMPLETE LINE OF RELAYS SERVING AMERICAN INDUSTRY

.PROCEED1NGS OF THE IRE.

.1tril. 105,,

Series 695 -P D. C. RELAY

For

Applications

Triplett 630-A Has No Counterpart

to WA
with a Mirror-Scale
with 'h.% resistors
Try This Volt-Ohm-Mil-Ammeter at your distributor's

TRIPLETT ELECTRICAL INSTRUMENT CO., BLUFFTON --

OHIO

22A

PROCEEDINGS OF TIIE IRE.

April, 1953

'

e

é

EXTRUDED

,.. mow CERAMICS "1M

at

VOLUME PRODUCTION is available for your extruded ceramics at AMERICAN LAVA CORPORATION. Several batteries of presses from 10-ton to 100-ton capacity assure the right press for the job. Ceramics of uniform cross section up to 81/2 diameter can be extruded, sawed and machined to intricate shapes. These pictures show part of our extrusion equipment and typical AlSiMag ceramics made from extruded material. Send us your blue prints or sample: let us show you what we can do for you.

OF

CERAMIC

LEADERSHIP

AMERICAN LAVA CORPORATION

MOLE: New offices at CLEVELAND, OHIO and SYRACUSE, H. Y.

CHATTANOOGA 5, TENNESSEE

OFFICES: METROPOLITAN AREA: 671 Broad St., Newark, N. J., Mitchell 2-8159 · SYRACUSE, N. Y. PHILADELPHIA I649 N. Broad St., Stevenson 4:2823 ·CLEVELAND, 5012 Euclid Ave.. Express 1:6685 CHICAGO, 228 N. LaSalle St., Central 6-1721 · ST LOUIS, 1123 Washington Ave., Garfield 4959
SOUTHWEST: John A. Green Co., 6815 Oriole Dr., Dallas 9. Dixon 9918 · NEW ENGLAND, 1374 Mass. Axe., Cambridge, Moss., Kirkland 7:4498 · LOS ANGELES. 5603 N. Huntington Dr.,Capital 1:9114

Oscilloscope records are easily read
when prints are made with the Fairchild-Polaroid Oscilloscope Camera
There are three good reasons why oscilloscope traces can be read quickly and easily when they are photographed by Fairchild's adaptation of the Polaroid camera:
1 The trace reads normally--left to right--instead of reverse. 2 Reduction is exactly half life-size for easy measurement of values, especially when
agrid is used. 3 Each print records two images, especially handy for before-and-after work. Operation is as easy as 1-2-3. In two minutes or less you can set up the camera, snap the shutter, and pull the tab. Then you wait one minute more and remove the finished print. No focusing and no special training are required. Important note--Delivery of Fairchild-Polaroid Oscilloscope Cameras can be had in just afew weeks. Write today for prices and information.
For still or continuous-motion recording on 35-mm film or paper Use the FAIRCHILD OSCILLO-RECORD CAMERA
Speed is continuously variable through an exclusive electronic control. Film is sprocket-driven so there is no slippage. There are no belts or pulleys. Top-of-scope mounting eliminates need for tripod and keeps scope controls easily accessible. Provision for three film lengths-100, 400, or 1,000 feet. Delivery in about four months.

· Full information about the Fairchild-Polaroid and OscilloRecord Cameras awaits your request. Write today to Fairchild Camera and Instrument Corporation, Robbins Lane, Syosset, Long Island, New York, Department 120-19C.

lieeel/I fes
OSCILLOSCOPE RECORDING CPMERAS

PROCEEDINGS OF 'THE I.R.E.

April, 195

SPECIFICATIONS

Capacitance ... Within stated tolerance at 1KC, 1to 5 volts RMS, and 25 °C.

Standard Capacitance Tolerances

± 5%, ±10%,

± 20%, guaranteed minimum value. (± 5%, and in

some cases ±10%, not available on Hi-K items.)

Standard Voltage Ratings, D. C. Working ... 1000, 1500, 2000, 3000, 5000, 6000.

Dielectric Strength Test ...Two times rated working voltage, with megohm series resistance.
Life Test ...1.5 times rated working voltage at 85°C. for 1000 hours.

Insulation Resistance ... 10,000 megohms minimum.

Temperature Characteristic and Power Factor ... One of four, depending on capacitance value and rating.

Characteristic P100 thru N1400

Maximum Power Factor
0.1%

Exact conformance per Erie GPI Ceramicons, Bulletin 312.

Hi-K-1 2A Hi-K-35 Hi-K-70

2%
22%%,(

Exact conformance per Erie Disc Ceramicons, Bulletin 438.

ERIE Disc Ceramicons have proven to be an are marked with nominal capacitance and

ideal adaptation for high voltage application. rated voltage.

Inherent construction simplicity means greatest economy yet for comparable voltage and capacitance values.
They are amazingly easy to install in small spaces ...they simplify soldering and wiring operations, and speed up the assembly line. Erie Disc Ceramicons consist of round flat dielectrics with fired on silver plates and leads of No. 22 tinned copper wire firmly soldered to silver electrodes.
The Ceramicons are phenolic dipped and

Rated D.C. Voltage 1000 1500 2000 3000 5000 6000

Capacitance Range, MMF 6 --10,000 5 -- 6,400 3.5-- 5,100 6 -- 3,250 6 -- 520 5 -- 340

Write for Bulletin 440. Erie Standard 500 volt By-pass and Coupling Disc Ceramicons are described in Bulletin 438. For Tempera-

vacuum wax impregnated for moisture seal. ture Compensating Disc Ceramicons see Erie

They are identified by the Erie trademark and Bulletin 439.

ERIE components are stocked by leading electronic distributors everywhere.

ERIE RESISTOR CORPORATION ...ELECTRONICS DIVISION

Main Offices: ERIE, PA.
Soles Offices , Cliffside, N. J. · Philadelphia, Pa. · Buffalo, N. Y. · Chicago, Ill. Detroit, Mich. · Cincinnati, Ohio · Los Angeles, Calif.
Factones. ERIE, PA. · LONDON, ENGLAND · TORONTO, CANADA

1,

(,I

II? F.

25.

Speer makes it easy for you to choose the right Carbon resistor!

ze.,Q *eel' de.
C.P

Z.*
o
jb, or. e

··· 9Par 11,0

Ce

·

.1 /4 0

o .ee44P

"

se'c-zee_ek cje

,ee

Speer fixed carbon resistors are made and color-coded in compliance with RTMA and Jan-R-11 standards. This helps your employees to avoid errors--to use the right resistor for the circuit every time.
Speer resistors are made better -- are the right resistors for every circuit. By using very high pressure to create an inseparable bond between the protective phenolic shell and the carbon core, Speer gives its resistors these important advantages:
1. More efficient heat transfer.
2. Greater ability to sustain overloads for long periods of time.
3. Uniform diameter resistive element for the entire length of the resistor, which eliminates weak points and potential burn-outs.

4. Uniformly thick protective covering over the entire length, which eliminates low-voltage breakdown between resistive element and adjacent conductor -- makes for minimum change in resistance when subjected to adverse humidity conditions.
All shipments of Speer resistors are given numerous tests for resistance rating, and are backed by aminimum resistance change when exposed to an accelerated ten-day humidity test. Speer manufactures acomplete line of 34, 1and 2 watt resistors in all standard values from 10 ohms to 20 megohms. Nonstandard values are available for special applications.

Write today for
your free copy of Speer
Resistor's new complete catalog

SPEER RESISTOR DIVISION
SPEER CARBON COMPANY
St. Marys, Pennsylvania
Other Divisions: Jeffers Electronics International Graphite & Electrode

l'1%>()( ELPIAG.S W. 111E 1.R.E.

April, 1953

When it comes to making a,eariérae;143
in space...
Stackpole cup cores with their self-shielding
characteristic can be mounted close to the chassis or any other metal part for maximum results in extremely close quarters. In some instances, the high Q circuits made possible through their use permit reduction in the number of tubes needed.
Standard types include numerous shapes and sizes, each available in a wide range of permeability possibilities. Highly specialized types to meet the most critical specifications can be engineered and produced from a broad background of experience in this exacting field.
Electronic Components Division
STACKPOLE CARBON COMPANY
St. Marys, Pa.

PROCEEDINGS OF THE I.R.E.

April, 193

Other Stackpole core types include:
ALL STANDARD MOLDED IRON CORE TYPES, SIDE-MOLDED, CHOKE COIL CORES, SLEEVE TYPES, THREADED TYPES and COIL FORMS. ..also Stackpole CERAMAG" CORES (FERRITES).
Write for Electronic Components Catalog RC-8
27.

electronic wire and cables for standard and special applications
Whether your particular requirements are for standard or special application, choose LENZfor the finest in precision-manufactured electronic wire and cable.

GOVERNMENT PURPOSE RADIO AND
INSTRUMENT HOOK-UP WIRE,
plastic or braided type, conforming to Government Specification JAN -C-76, etc., for radio and instruments. Solid or flexible conductors, in a variety of sizes and colors.

SPECIAL HARNESSES, cords and cables, conforming to Government and civilian requirements.

RADIO AND INSTRUMENT HOOK-UP WIRE,
Underwriters Approved, for 80 C., 90 C. and 105' C. temperature requirements. Plastic insulated, with or without braids.

RF CIRCUIT HOOK-UP AND LEAD WIRE
for VHF and UHF, AM, FM and TV high frequency cir· cults. LENZ Low-Loss RF wire, solid or stranded tinned , copper conductors, braided, with color-coded insula-
tion, waxed impregnation.

SHIELDED JACKETED MICROPHONE CABLE Conductors: Multiple 2 to 7 or more conductors of stranded tinned copper. Insulation: extruded colorcoded plastic. Closely braided tinned copper shield. Tough, durable jacket overall.
vAlor7., x,utexxx.1

SHIELDED MULTIPLE CONDUCTOR CABLES
Conductors: Multiple --2 to 7 or more of flexible tinned copper. Insulation: extruded color-coded plastic.Closely braided tinned copper shield. For: Auto radio, indoor PA systems and sound recording equipment.

JACKETED MICROPHONE CABLE
Conductors: Extra-flexible tinned copper. Polythene Insulation. Shield: J36 tinned copper, closely braided, with tough durable jacket overall. Capacity per foot: 29MMF.

TINNED COPPER SHIELDING AND
BONDING BRAIDS
Construction: #34 tinned copper braid, flattened to various widths. Bonding Braids conforming to Federal Spec. QQ-B-S75 or Air Force Spec. 94-40229.

SHIELDED COTTON BRAIDED CABLES Conductors: Multiple --2 to 7 or more of flexible tinned copper. Insulation: extruded color-coded plastic. Cable concentrically formed. Closely braided tinned copper shield plus .brown overall cotton braid.
PA AND INTERCOMMUNICATION CABLE Conductors: #22 stranded tinned copper. Insulation: textile or plastic insulated conductors. Cable formed of Twisted Pairs, color-coded. Cotton braid or plastic jacket overall. Furnished In 2, 5, 7, 13 and 25 paired, or to specific requirements.

CHECK Pa FIRST!

Lenz Electric Manufacturing Co.
1751 N. Western Ave., Chicago 47, Illinois

Our 48th Year in Business

cords, cable and wire for radio ·p. a.. test instruments ·component parts

PROCI-.1

OF 771E I.R f

.Ipril, 1053

"H'211 3H.L .30 SDNICIffg.9021d

TYPE &
IP434 ISJO IN344 (S) IN35 (S.K) 1P438 (S.K)
1N384
1H39 (S,K)
IN40 (S) 11441 (S) IN42 (S)
IN43 (WE) IN44 IWG 1N45 IVIE1 IP446 11447 IVIE) IN48 (GE) 11451 (GE) 1H32 (GE) IN54 (S.K)
IN344 (s)
11455 (SK)
1N554 IN.% (5X) IN564 (S) IP457 (5,K) 11458 (5,10 IMITA (S)
11460 (s,8)
11461 DG
1N63 1N64 (GE)

0.E. REPLACEMENT
11448 11452 GSA

MINIMUM FORWARD CUL
0 +IV. (MA)
5.0 4.0 5.0 4.0 7.3 4.0 3.0

PEAK INVERSE VOLTAGE (VOLTS)
75 85 75 83 73
es
120

1N70

3.0

125

4.0

120

1N63

4.0

125

1.5

225

IP475

2.5

125

IN73

® 12.750 +1.5V.

15.0

+I7V.

75 75

None

12.75 0 +1.5V.

120

1N73

13.0 0 +1.7V.

75

5.0

60

11469

5.0

75

3.0

115

1N70

3.0

125

3.0

75

IN63

2.5

85

3.0

to

11448

4.0

85

3.0

115

11470

3.0

125

4.0

85

2.5

so

4.0

85

3.0

73

1P469

5.0

75

5.0

75

1H52

4.0

85

3.0

170

IN75 IN63 1N69 IN69 11'452 1P463 IN63 11464

2.5

125

4.0

170

4.0

125

13.0

.50

5.0

75

15.0

so

5.0

73

4.0

90

4.0

85

4.0

120

4.0

123

4.0

120

4.0

123

30

-03 0 +0.25V.

20

5.0

140

IN63

4.0

125

4.0

123

.03 * +o.238.

20

COI«. REVERS& VOLTAGE (VOLTS)
60 70 60 70
so
70 100
100 100
100 200
100 25
so
60
100
70
70
100 70 40 70 35 60
so
70 150
100 150 100
40
to
40
ao to
70 100 100 100 100
25
130
100 100

MAXIMUM

e REVERSE CUL (o.)

-SOV.

OTHE*

800. 833 500 150 150
300
50
50

50 é -10V. 30 @ -I0V
10 -lov.1

6 0 - 3V. 625 -100V.

25 -10V.

- 5lé -3V.

500

100V.

200 0 -100V. 800 0 -200V.

400 -10V. 500 -I0V.

850 850 1000 300 410 250 1500 833 410 300 833 1667 150
850 100 150
50
so
850
850
150
50
50
50 50

®e 6(é -3V.
625 -100V. 50 -10V. 20 0 -5V. 500 -10V.
250 -10V.

e 4 -3V.
25 0 -10V.

IO - 10V. 500-10V.
70 -10V.

300 0 -100V. 800 -150V.

500 é -150V.

3000-20V.

500-10V.

300 50

ce

--310cVw..

500 0 -75V.

500(0 -1 00V. 600 0 -100V.

230 -1.3V. 300 0 -100V. 700 0 - I25V.

25 (4 - 13V.

PEMARKS
61/ 4.86.6 pairs;
Seo Nok. I
Good, Se* Note 2 Ouadi See Note 3 Oueds See Note 2 Oued, Seo Note 3
See Note 4 See Note 5 Sels Noie 5

TYPE & MM.
IN65 (GE) IN66
)N67
1N68 (R)
IN69 (GE) IN70 (GO 1N71 Mi IN72 (GE) IN73 (GI) IN74 (GE) IH73 (GE) CK705 GO CK706 (R)
CK707 (E)
0(708 (R) 0(709 (R)
0(710 (RI
CK711 (R)
CK7I2 PD
0(715 (R)
1091 (GE) 11492 IGG IN93 (GE) IN94 (GE) GI I(GE) GI IA IGE)

G.E. REPLACEMENT
IP448 IN63 1N73
None

MINIMUM FORWARD CUR.
+IV. (MA)
2.3 5.0 4.0 4.0 4.0 3.0 2.3 5.0 3.0
e 0.8 +-SV.
15.0 0 +I.7V. 13.00 +I.8V.
2.5

IN64 1052

.0 3 l* +0.25V. 3.5 4.0

IP473 G7A IN73 IN75 11452
G7A G7f

15.0 +I.7V. 30 +0.3.1.
15 0 +I.7V. 2.0 2.5
21 * +2.0V. 4.0 3.0
0.80 +3V.
0 .8 0 +.5V. 1000 1000 1000 1000

PEAK INVERSE VOLTAGE (VOLTS)
85 70
es
100 12$ 120
75 125
$ 73 75 125
50 20 100 85
75 10
75 225 125
75 85
so
5 100 200 300 400

CONT. REVERSE VOLTAGE (VOLTS)
70 60 70
80
100 100
100 60
100
100
40
so
70
60
2.)0 100
73 70 40

MAXIMUM

REVERSE CUR. 44

0 -30V.

OTHER

250

800

$0 - 10V.

833

so

5(g) -5V.

so

625 -100V.
so

850

50 -10V.

300

250 -10V.

804 lé -.5V. 50 0 -10V 30 0 -I0V. 50

200 @ -10v.

250 -1.3V.

loo

e® -5V.

150

50 0 -10V. 200 0 -.6V.
30 50 - 10V.
800 0 -200V. 50
2500 -40V. 150
10 (é - 10V.
800 0 -.5
800 e -.5

REMARKS
Oued Se. Note 6 Oued; See Note 3 Good, See Neto 3 Som es 11466 See Note 7 Se. Neto 3
Sema as 11468 Oued, See Net. 8 &t'ad; See Note 3 See Neto 9 See Nele 6 Ouod,SeeNete 10 Good, See Neto 3
UHF Miner See Note 6 Ff1.11/1111CY Molt. Frequeer, Mule.

I Diffused Junction Rot:Mers
1
Transistor
Transistor

NOTE 1: Forward resistoncei motched within 10% ot +IV.

NOTE 2: Four diodes in tube shell with forward resistances balanced within +2.5% ot +1.59. Forward resistances of eads pair

matched within 3ohms.

NOTE 3: Four diodes in hermetically sealed tube shell. Forward resistances moiched withis 6.7 ohms for 1N73 and 13.4 ohms for 11474

at 15 Mo. Forword resistances of midi poir motched within 2ohms for 1P473 ond 6.7 ohms for 1N74 et 15 Mo.

NOTE 4: Tested with I.8V. EMS input at 40 Mc, 70% modulated ot 400 cycles. Minimum output is 1.89. peolvto-peolt ord0/4 4700

ohms shunted by 5MMF.

NOTE 5: Tested with 0.1V. EMS, 44 Mc input to lost I.F. grid. Minimum output is 100 ma through 3600 ohms shunted by 5MMFD.

NOTE 6: Movinturn conversion Ion is 10db ineosured ot 900 Mc Irish 0.7 M« LO. level and d4 forward bics front a0.25V..

250 ohm source. NOTE 7: Tested vie 0.1V. EMS, 50 Mc input to lostl.F. grid. Minimum output is 330 osa through 5100 ohms shunted by 5MMFD.

NOTE 111: Four diodes in tube shell with forward resistonces mahshed within 2.5%. At -109. diodes are netched 2.5% os s'Ubaye a

resistance greater thon 1.0 meg ohm.

NOTE 9: Typical noise temperoture ratio of 7.

NOTE 10: Foo diodes etube

Ends pair of diodes is shunted by 10,000 ohnts center-topped ond the celtes tap of residor and

diodes connected by , microoninseter. Will. 0 to +3V. dc applied imbolonce miment limit is 5MA.

· Fr"' a free file card copy of this data write: General Electric Co., Section 5243, Electronics Park. Syracuse. N.Y.

NEWS and NEW PRODUCTS
April 1953

Millimicrosecond Pulse Generator

These manufacturers have invited PROCEEDINGS readers to write for literature and further technical information. Please mention your I.R.E. affiliation.

The Panel on Electron Tubes of the Research and Development Board is sponsoring asymposium on CeramicTo-Metal Seals at the Rutgers University School of Ceramics on April 21, 1953. For further information contact Harry J. Sullivan at 346 Broadway, New York, N.Y., REctor 2-8000.

Electrical and Physical Instrument Corp., 42-19 27th St., Long Island City, announces the Model 100 millimicrosecond pulse generator, which utilizes anew meth(x1 of pulse shaping. Square pulses of rise time of 1 millimicrosecond, (0.001 µsec.)
with acomparable decay time and of width which can be varied from 2 millimicroseconds to several microseconds are generated. The maximum pulse amplitude is 100 volts into low impedance cables (such as 50 ohms) for a pulsed power output of
200 watts; outputs up to 800 watts are also available. The output amplitude can be at-
tenuated a total of 84 db in one db steps to cover the range of 100 volts to 0.006 volt. A polarity switch on the front panel allows the selection of either positive or negative pulses. Two or more pulse out-
puts, each of which can be individually attenuated and delayed are available ill some models. The repetition rate is 60 pps with control for a single pulse operation available. Pulse widths are: 2.0 millimicroseconds 2.0X 10-8,5.0 millimicroseconds 5.0 X10-9,7.5 millimicroseconds 7.5 X 10-9, 10 millimicroseconds 10-8,25 millimicroseconds 2.5 X10-8, 50 millimicroseconds
5X10-8,-iezr microsecond 10-7.Other values of pulse widths are available upon request, and instructions for obtaining any pulse
width desired from 2millimicroseconds to several microseconds are included with the unit.

Time Calibrator
The Type 190 Low-Frequency Time Calibrator, a synchronous-motor driven device furnishing pulses at intervals of 0.01, 0.1, or 1.0 second, is now available from Owen Laboratories, Pasadena, Calif.
It is intended for use with oscilloscopes and various types of recording equipment in electrical, mechanical, and biological investigations. Pulse amplitude is about 1.5 volts. Size is 4X31 X3 inches, and the price is 1648 postpaid.
Sharp-Cutoff Pentode
Tube Dept., Radio Corp. of America, Harrison, N. J., has a new type 5654, a "premium" version of the miniature sharpcutoff pentode 6AK5 for use as a broadband RF or IF amplifier in mobile and aircraft receivers. It is constructed and processed to meet military requirements.

Elapsed Time Indicator
R. W. Cramer Co., Centerbrook 5, Conn., has a new type ET time totalizer, used to measure and indicate elapsed time intervals wherever very precise measurement of time is required.
Two models are available: One has scale divisions of 0.01 second and a total range of 50 seconds, and the other has divisions of 0.01 minute and atotal range of 50 minutes. Accuracy for either is better than 0.02 of of 1per cent.
Prime feature of the new time totalizer is a unique differential clutch mechanism that insures high accuracy and positive clutching throughout the life of the device. Instead of the conventional friction or face plate clutch, the motor is here permanently connected to the sun gear of adifferential gear system. One of the differential members is connected to the pointer system, while the other goes to a free gear.
Forms of this time totalizer are available to meet the most exacting military specifications with regard to shock, vibration, temperature, etc.
For complete details write for Bulletin 690.
Tube Bottoming Machine
Kahle Engineering Co., 1307 Seventh St., North Bergen, N. J., has announced the production of a completely automatic tube bottoming machine.
This special-purpose machine, Model 2048, was designed and built to produce miniature lamp bulbs for switchboard and telephone use.

-4.e0 kl geitttbti·iriear

e`r-." ·

Transformer Catalog
Peerless Electrical Product Div., Altec Lansing Corp., has just released its new 15-page transformer catalog and price list containing 92 items. This catalog lists many new items including the new line of 20-20 plus transformers, and also describes facilities for the design and manufacture of Class A, B, and H transformers, which are built to meet JAN-T27 and MIL-T 27 specifications. Catalogs and price lists may be obtained by writing to Peerless Electrical Products Div., Altec Lansing Corp., 9356 Santa Monica Blvd., Beverly Hills, Calif., or 161 6th Ave., New York 13, N. Y.
30A

Featured in the 5654 is a compact
structure especially designed to provide increased mount strength against shock and vibration, and a pure-tungsten heater to give long life under conditions of on-off switching.

The machine, producing 4,000 units

per hour, eliminates older methods of lift-

ing the glass from one position to the next

by using acontinuous conveyor principle.

Cut tubing of required length is dumped

into arubber-lined hopper; the glass is then

indexed straight through the machine and

is not "jumped" or "bumped" in the proc-

ess. In machine breakage and rejects are

consequently held to aminimum. In addi-

tion, Model 2048 can be used to produce

round or flat bottomed test tubes, vials,

and containers.

(Continued on page 444)

PROCEEDINGS OF TIIE I.R.E.

April, 1953

Shocki News »au

Since Daven originated the first pie-type wire wound resistor more than ageneration ago, it has pioneered many innovations in the production of resistors.
Today, only Daven uses astranded lead wire to connect the resistance wire to the solder terminal of the Super Davohm Precision Wire Wound Resistor.
As a result, no matter how much strain, stress, heat or pressure is applied to the solder terminal, no accompanying shock is put upon the fine resistance wire itself, but is absorbed by the heavy lead wire without adversely affecting the resistor in any way.
Therefore, Super Davohm Resistors are substantially more rugged than conventional resistors and are able to withstand unusual vibration, rough treatment and abnormal shocks.

This exclusive Daven feature, plus the many other quality aspects of Super Davohm Precision Wire Wound Resistors, makes Daven the leader in the resistor field.
The Super Davohm line includes resistors made in accordance with MIL-R-93A specifications, as well as sub-miniature units to give you the most complete selection of resistors available anywhere. Deliveries can be made to meet your requirements.
Write for assistance with your problems, and ash for a copy of Daven's complete, new brochure on Super Davohm Precision Wire Wound Resistors.

THE

Val«)

195 CENTRAL AVENUE, NEWARK 4, N. J.

,,.GR
S A

ICON ,,

INDUSTRIAL TELEVISION

-

%

OrtPolt>

Standard or portable type cameras designed with New "STATICON" TUBE... GPL Remote Control optional

A SPECIAL SERVICE
For Users of
INDUSTRIAL TV
GPL announces a special engineering service for firms studying industrial TV. You are invited to submit your problems to GPL engineers for a survey of camera type needed. lenses, monitors, remote control, and complete installation for maximum economy and efficiency.
1

STANDARD STATICON
A very compact camera, designed for fixed installation and continuous duty' under minimum light conditions. Separate control monitor and sync generator at master control point. Standard TV receivers can be used as optional monitors. Available with remote control of pan and tilt, lens change, focus and iris adjustment.

PORTABLE STATICON
For field use, multiple setups ...hand-held or tripodmounted. Packaged as one unit with built-in sync generator, monitor and transmitter in camera housing. Standard TV receivers as added monitors. Rugged but compact for reliability in portable uses.
Specifications for both cameras available on request

Write, wire or phone

General Precision Laboratory

INCORPORATED

PLEASANTVILLE

NEW YORK

Cable address: Prelab

Export Department: 13 East 40th St., New York City Cable address: Arlab

TV Camera Chains · TV Film Chains · TV Field and Studio Equipment · Theatre TV Equipment

PROCEEDINGS OF TIIE I.R.E.

e

Rcee-Set`.` \I`stortees le, smaller --same magnetic stderencgth
14.11ctell the Rollet·Sinitli Corporation idea to tue geaiie their electrical instruments to meeyet eilitaty Specifications, they discovered that th needed a
smaller permanent magnet -- one that would do tbe

samTehejoybcaaslltehde onldCornuecitbllaee'yswetercehnuiscianlg.service for assistance. le short order, Roller·Smitla'sroubcjiebclteisldee. was attained. Vor through improved aesign, and

better quality control in production, Cmaller

velopea an ana lighter

alnico magnet that was 13.5c/0 than the previous one ·..but

wsithmtahney

san'iTehemaiglnoeltliecrSsrterietnhgtsht.ory is typical ofthebecause cCarsuecsisbollev emaagwnietnthsChraucviebtlhemeaAhrlikngeibtceo.st'CMrgauagcpniefbtllsuex,.hpaese buenietn

otfheweliegahdtinogfparoyauocnesrttahorefteAa.ln-iWchoeIn' eyroeutebneeeet eaamgalgentest

since the illaustry

ble.

problem, call on Cruci

CRUCIBLE first name in special purpose steels

53 r«e 70-7e se-fea.é-e,y PERMANENT ALNICO MAGNETS
CRUCIBLE STEEL COMPANY OF AMERICA, GENERAL SALES OFFICES, OLIVER BUILDING, PITTSBURGH, PA.
STAINLESS·REX HIGH SPEED·TOOL·ALLOY·MACHINERY·SPECIAL PURPOSE STEELS

PROCEEDINGS OF THE I.R.E.

April, 1953

3 3 A

ACTUAL SIZE

.with a rheostat or other resistance type controls. You will find POWERSTAT type 10 the ideal source of variable a-c voltage control of 50-100-150 watt loads.

POWERSTAT type 10 is rated:

INPUT: 120 Volts, 60 Cycles, 1 Phase

OUTPUT:

0-120 Volts, 0-132 Volts, 1.25 Amperes, 150/165 VoltAmperes

POWERSTAT type 10 weighs only I POUND, 13 OUNCES.

· EFFICIENCY

of type 10 is high ... does not control by dissipating power in the wasteful form of heat as does a resistance type control.

· SPACE REQUIREMENT of type 10 is only n6 by 3V8 inches. Not only is it compact but since it does not produce heat there is no ventilation problem.

· CONSTRUCTION of type 10 is rugged for long life and dependable service.

· ADAPTABILITY

of type 10 to any load within its rating is possible without tailoring as is necessary with a resistance type control.

· RATING

of type 10 is conservative with the rated output current available at any brush setting.

· MOUNTING

of type 10 is simple by means of a single hole in the panel. It is locked in position by a keying arrangement.

· OPERATION

of type 10 is smooth, stepless and silent.

· PRICE

of type 10 is low . comparable to any other type of a-c voltage control apparatus of equal capacity and characteristics.

A comparison of POWERSTAT type 10 with a rheostat or other resistance type controls reveals that it is the logical answer to any variable a-c voltage control problem involving loads up to 150 watts.
Additional information on POWER. STAT type 10 is available by writing
1104 Mae Avenue, Bristol, Conn.

POWERSTAT type 10 is a small, compact autotransformer of toroidal core design with a
movable brush-tap. Rotation of the tap delivers any output voltage from zero to, or above, line voltage. It is tapped to allow compensation for a 10 per cent drop in line voltage.

34.s

PROCEEDINGS OF THE I.R.E.

April, 19.53

·

oae4=4,,ede,

PICTURE TUBE

*with Internal Magnetic Focus

Saves parts, circuitry, labor in set manufacture! Gives needle-sharp over-all image! Permanently pre-focussed for best viewing!

COMPARE (left) the bulky parts needed for astandard tube with (right) the clean simplicity of on i-m-f tube ready to install!

The external ion-trap magnet on this standard tube,
is an extra cost item for the TV manufacturer and requires special adjustment. The focus coil and complicated mounting also mean extra cost.They take up space, add weight, consume assembly and adjustment time. Get rid of all three parts with G. E.'s new i-m-f tube!

Now, no hard-to-adjust external ion-trap magnet! No
focus coil, or external focus magnet, with cumbersome bracket! Instead, an i-m-f tube calls for just two parts
when installed, both of them compact: (1) a closefitting steel shunt band that is easily slipped on and (2) a small centering device to position the picture.

ON this 75th anniversary year, General Electric takes pride in announcing its i-m-f picture tube as the latest in along series of significant G-E "firsts". To the many advantages given by internal, factoryadjusted ion-trap and focus magnets, can be added radically improved design in important tube details. One example of this is the new, precision-made metal "lens" that greatly narrows the electron beam,

assuring clean, sharp picture definition over the entire TV screen area. Now 90°-sweep tubes can
have good detail across the whole face! You can expect production soon in 21" size. Other i-m-f types
will be added rapidly. Television manufacturers and television designers will be sent full informa-
tion on request. Tube Department, General Electric Company, Schenectady 5, New York.

GENERAL

ELECTRIC

GRAMER fr TRANSFORMERS MEET MIL-T-27 GRADE 1CLASS A SPECIFICATIONS WITH IN-PLANT TESTING FACILITIES

TEMPERATURE and IMMERSION CYCLING
FIVE (5) CONTROLLED CYCLES
OF 15 MINUTES EACH STEP
Step 1. Oven 185° F. Step 2. Room Temperature Step 3. Cold Chamber
67° F. Step 4. Room Temperature Step 5. Saturated Salt Bath
Total Immersion
5 r

EXACT ELECTRICAL MEASUREMENTS
INSULATION RESISTANCE measured accurately E r >
to 2,000,000 Megohms
TEMPERATURE RISE TEST

·C 70 60 50 40 30 20 10
o -10
36.

95% li.r1

OEZ

95F

--I

1---1

MOISTURE RESISTANCE
Transformers withstand 10 humidity cycles shown at left and are subjected to a 15 minute vibration test, 10 to 55 cycles per second. Some specifications require DC polarizing voltage applied from terminals to case during the entire time units are in humidity cabinet.
GRAMER TRANSFORMERS CAN TAKE IT!

HUMIDITY CABINET

AI
VIBRATION MACHINE
GRAmER1 TRANSFORMER CORPORATION 111111111K We Invite You--Send Your Specifications c/o Dept. I.R.
lie MI 2134 NORTH PULASKI ROAD · CHICAGO 39, ILLINOIS

PROCEEDINGS OF THE I.R.E.

April, 1053

1

"BUILT-IN EYELETS SPEED

PRODUCTION ...SAVE DOLLARS!"

with this New Sylvania Integral Eyelet Socket

You'll speed up radio and television set assembly and pare down costs with this new Sylvania socket!
The eyelets are formed into the saddle and actually function as rivets. Just 2simple operations and these sockets are firmly secured to the chassis. You save rivet costs, save time, and get a sturdy, durable, top-quality job.

Made with 3 types of bases
These new Sylvania sockets are now available with 7-pin, octal, or 9-pin bases. Insulators are either general-purpose or low-loss phenolic.
For prices and full information about this latest Sylvania quality part, write today to: Sylvania Electric Products Inc., Dept. 3A-4504, 1740 Broadway, New York 19, N. Y.

PROCEEDINGS OF THE I.R.E.

April, 1953

"ANOTHER IMPROVED PART
BY SYLVANIA"

BIB ·IM

a MI Mil

,PY

SYLVAN IA
RADIO TUBES: TELEVISION PICTURE TUBES, ELECTRONIC PRODUCTS; ELECTRONIC TEST EQUIPMENT; FLUORESCENT TUBES, FIXTURES, SIGN TUBING, WIRING DEVICES;
LIGHT BULBS; PHOTOLAMPS; TELEVISION SEIS

You Name The Height Your Antenna Must Reach...
TRUSCON TOWER ENGINEERS will get it up there ..t0 stay!

· Whether your needs call for a

medium-sized 300 foot tower, a

lofty 1200-plus foot giant, or any

size in between,Truscon engineers

have the answer ...or can get it

to you fast. Truscon has designed

and built many hundreds of radio

towers now serving in all kinds

of climate and all types of topo-

graphy. Truscon builds 'em for

you tall or small ...guyed or

self-supporting ... tapered or uni-

form in cross-section... for AM,

FM, TV, and Microwave trans-

mission. You just name the height

your antenna must reach; then

write, wire or 'phone your nearest

,4

Truscon district office or "tower

headquarters" in Youngstown to

get your tower program going

as soon as defense require-

ments permit.

TRUSCON STEEL DIVISION

REPUBLIC STEEL CORPORATION 1072 ALBERT ST.
YOUNGSTOWN 1, OHIO

TR1JSCON

MARK OF MERIT TRUSCONe

PRODUCTS

-- a name you can build on

38 \

PROCEEDINGS OF THE I.R.E.

.4pril, 1953

--out of sight, but in the picture

Whenever you turn on television you are using a little-seen, but essential, material called Synthane.
Synthane is alaminated plastic of multiple virtues, which recommend it for many jobs in television.
Synthane is an excellent insulator, laminable with metal, hence, agood base for space-reducing "printed" circuits. Synthane is notable for low power factor, low moisture absorption, and ease of fabrication, three properties desirable for radio and television insulation. Synthane

plays asupporting part in many behindthe-screen and behind-the-camera applications.
Synthane is also light in weight, strong, vibration absorbing, chemically resistant, high in dielectric strength, dimensionally stable, heat resistant to about 300°F.
There may be a place for Synthane in your product. To find out more about the possibilities of Synthane for your purpose, write for the complete Synthane Catalog. Synthane Corporation,12 River Road, Oaks, Pennsylvania.

Synthane in Television .·.
A--Television camera parts 8--Television receiver printed
circuits--metal foil on Synthane sheets C--Channel selector switch insulation

eitt ¡AuteetA ieitte4eut, L4Webtiale SYNITHIANe

PROCEEDINGS OF THE I.R.E.

April, 1953

LAMINATED PLASTICS 39A

Séarching

for more effective automatic control instruments?

Ketay's knowledge and experience will be helpful.

e NEWEST KETAY PRODUCT

It was gained in developing and designing dozens of the precision control instruments that are today's military standards.

· Take Ketay's Size 23 Synchro, for instance. This single development is

111111111111111111
TRANSFORMER SYNCHRO CONTROL
TYPE - 0- 14450 26/11.8 VAC -400 CYC1 S
KETAY MFG. CORP.
NEW YORK, N.Y.

· an integral component in the controlling of the Skysweeper .... the Army's latest automatic antiaircraft gun. Ketay's mass production
· techniques are making such controls economically practical.
Our instrument engineers, with more than 25 years of specialization in this field, could well put an end to your search for more

ACTUAL SIZE

effective automatic controls. There's no obligation, of course. Why not write for more information to Dept. A.

SUBMINIATURE TYPE

101 A2D SYNCHRO

CONTROL TRANSFORMER

Ketay Part No.

D-14450

Voltage rating

11.8v/0.4 y per deg.

Operating frequency 400 cps

Input power

0.4 w max.

Input current

140 ma max.

Input impedance

61 /77° ohms

Secondary voltage 23.2 ±. 1y

Total null voltage 40 my max.

Fundamental Component of

Null voltage

30 my max.

Time Phase Shift

7°

Moment of Inertia

8.8 X 10-5 slug in2

Frictional Torque .05 oz. in.

Electrical Accuracy --max. 10'

WHEN USED AS A

CONTROL TRANSMITTER

Voltage rating 26/11.8 v.a.c.

Input power

0.4 w max.

Input current

65 ma max.

Input impedance

475 /77° ohms

Output voltage 11.8 y ±- 0.3 y

Time phase shift

7.3°

40A

eta

MANUFACTURING CORP.

New York, N. Y.

Hawthorne, Calif.

Executive Offices 555 Broadway, New York 12, N. Y.

EIMMTEEM1 of precision instruments
· SYNCHR OS · SERVOS · RESOLVERS · MAGNETIC AMPLIFIERS · AUTOMATIC CONTROL SYSTEMS
· ELECTRONIC EQUIPMENT

PROCEEDINGS OF TIIE 1.R.E.

April, 1953

(lieelleiffiwide/ mg*
NI

4.

Model 292X
SIGNAL GENERATOR
Frequency Coverage: 125 KC to 220 MC
Calibrated Output: Less than 1 microvolt,
up to 100,000 microvolts.

Professional engineers and technicians everywhere constantly rely on the accuracy of calibration and long dependability of HICKOK instruments.
In electronic instruments, HICKOK pioneering leadership has been acknowledged for over 42 years.
THE HICKOK ELECTRICAL INSTRUMENT COMPANY 10514 Dupont Avenue ·Cleveland 8, Ohio

PROCEEDINGS OF 711E 1.R.E.

April, 1953

4IA

ere is ug-in I nut onstructi n

Everything you need to mount, house, fasten, connect, monitor your equipment.

/st

START WITH
ALDEN MINIATURE TERMINALS

llI pi

Here's a beautiful new little Terminal that really puts soldering on aproduc-

tion basis; taking a

minimum of space and material. Ratchet holds leads firmly for solder-

ing, no wrap-around or pliering necessary. Unique

punch press configuration gives rapid heat transfer,

taking less time and solder. Designed for Govt.

Miniaturization contracts. Staked in Alden Pre-

punched Terminal Cards, allow patterns for any

circuit.

Snap In

Held for soldering

No pliers--No twisting Wires--Buss bars easily accessible

to-

in

Both sides can be used

Ratchet holds leads firmly

Snip off loops desired to by-pass.

JUMPER STRIP

Stake under Terminals for common circuits. Loops match prepunched holes in Terminal Cards. Snip off loops desired to by-pass.

FOR YOUR SMALLER UNITS

2rvi Take Pre-punched Terminal « Mounting Card ready-cut to size
you require. Stake in Alden Miniature Terminals to mount your circuitry.

Attach Miniature Terminals,
40 111 Alden Card-mounting Tube Sockets and Mounting Brackets, which mount in the prepunched holes.

Prepunched Terminal Mounting Cards come in all sizes needed for Packages! miniature 7-pin and 9-pin units,
or 11-pin and 20-pin plug-in units. Card is
natural phenolic Viif thick prepunched on 1/4 " centers with .101" holes for taking the Miniature Terminals.

Alden Card -mounting Tube Sockets for miniature 7, miniature 9 and octal tubes, are complete with studs and eyelets for easy mounting on Prepunched Cards.

Mounting Brackets stake to the Prepunched Card, mount Card to Package Base and Lid.
o
o

FOR YOUR 2nd Lay out circuitry with Pre-
punched Terminal Mounting Card in lengths up to 3'.
READY MADE to fit various ready made Chassis sizes.

LARGER UNITS
3rd Attach Miniature Terminals, Card-mounting Tube Sockets and Mounting Brackets, which fit any of the prepunched holes.

Organize circuitry in compact vertical planes. Use both sides of Prepunched Card to stake in Alden Miniature Terminals to your circuitry layout. Vertical position gives ready accessibility; there is no "underneath" in Alden design.

Alden Cardmounting Tube Sockets, readymade in variety of sizes, complete with studs and eyelets for easy mounting on Prepunched Cards,

·

TO OBTAIN COMPLETE DETAILS.

Tiny Sensing Elements specifically designed to spot trouble instantly in any unit.
Here are tiny components to isolate trouble instantly by providing visual tell-tales for each unit.

Get one point of check of all incoming and outgoing leads thru ALDEN BACK CONNECTORS

"PAN-i-LITE" MIN. INDICATOR LIGHT
So compact you can use it in places never before possible. Glows like a red-hot poker. Push-mounts in .348" drill hole. Bulbs replace from front. Tiny spares are unbreakable, easily kept available, taped in recess of equipment. Alden #86L, ruby, sapphire, pearl, emerald.
MINIATURE TEST POINT JACK
Here are tiny insulated Test Point Jacks that make possible checking critical plate or circuit voltages from the front of your equipment panel--without pulling out equipment or digging into the chassis. Takes a minimum of space, has low capacitance to ground, long life beryllium copper contacts. Available in black, red, blue, green, tan and brown phenolic conforming to MIL-P 14B- CGF; also nylon in black, red, orange, blue, yellow, white, green. Alden #llOBCS.
ALDEN "FUSE-LITE"
Fuse Blows -- Lite Glows. Signals immediately blown fuse. Lite visible from any angle. To replace fuse simply unscrew the 1-pc. Lite-lens unit. Mounts easily by standard production techniques, in absolute minimum of space. 110V Alden #440-4FH. 28V #440-6FH.
Free Samples Sent Upon Request

462-2

SINGLE CHECK POINT

Here for the first time is a slide-in connector that brings all incoming and outgoing

leads to a central check point in orderly rows, every lead equally accessible and

color coded.

Color coding

Generous

Avoid conventional

bell-mouthing

rats nest wiring O « r

Permit direct efficient wiring

Floating clip action

Accessible uncongested solder terminals

STRAIGHT-THROUGH CIRCUITRY
Wiring is kept in orderly planes, avoiding rat's nest of conventional back plate wiring. Connections between Terminal Mounting Cards are through Back Connectors so that all circuitry is controlled at this central point. Incompatible volt: ages safely isolated and separated.

EASY INSERTION AND REMOVAL
Mating tolerances permit easy insertion and removal without demanding critical alignment tolerances. Assure proper contact, with safety shielding of dan. gerous voltages. Leads can be attached above, below or out of the back for most direct and efficient interconnects.

Ready-made Alden Back Connectors meet all conceivable needs, for

slide-in chassis replaceable ifi 30 seconds with spare.

i

or your ectronic quipmen

All designed all tooled production immediately available no procurement problems. Apply ALDEN Standards wholly or in part.

dit h After mounting your circuits ·· on Terminal Cards, use Alden Standard Plug-in Bases, Housings, Bails for packaging.
Min. 7 & 9-pin BASES available, also 11pin & 20-pin. BAILS& HOUSINGS or LIDS to match.
·
4th Fit Prepunched Cards carrying completed circuitry into Standard Alden Basic Chassis Body.

ALDEN PLUG-IN PACKAGES --
Using standard Alden Plug-in Packaging Components you can mount a tremendous variety of circuits on chassis or in racks.
Alden "20" Rack Mounting Socket with extended ears that mount side by side and in multiple rows on U-Channels that accommodate 50 Alden "20" Plug-in Units illustrated, in 10 ,/, x 19' rack mounting panel.

SLIDE-IN BACK
See description on opposite page.

CONNECTORS

ti L-,

HOUSE PLUG-IN UNITS IN ALDEN BASIC UNI -RACKS

·

· ·

I,

· · ·o

·

·

·i · · ·

r

8"

ir

···· ··· 2 .a..' ..

sr t rr

· ·

. .

· · -0

0

r° - ·.·1 e

FOUR SIZES OF CHASSIS MOUNT IN ANY COMBINATION
IN ALDEN UNI -RACKS

STACKED
Mounting all equipment in Alden Uni -Racks provides a uniform system easy to handle and ship. Can be installed and interconnected as fast as unloaded.

.

Prepunched to your specs. Easy accessibility at sides, front for completing wiring.
CZQ
SERV-A-UNIT LOCK
pulls in or ejects chassis.
SEND FOR FREE

ALDEN BASIC CHASSIS
with spares provides 30-second servicing for your unitized circuitry.

ALDEN UNIT CABLE
interconnects between lid» racks or other major cir· cuitry divisions. Quick, sure, coded means of isolating and restoring (with spare) inter-division. circuits.

"ALDEN HANDBOOK"

Your design and production men have always wanted these advantages: 1. Experimental circuitry can be set up with production components, cutting
down debugging time. 2. Allows technicians, rather than engineer, to debug, by taking out unit.
3. Given the circuitry, nothing further to design--make up from standard Alden components.
4. Optimum circuit layout using standard terminal card.
5. Absolute minimum requirements of labor, materials, space.
6. The various sub-assemblies can be built concurrently on separate assembly lines.
7. No tooling costs--no delays--no procurement headaches.
8. Fewer prints--smaller parts inventory.
9. Can subcontract assemblies.

Your customers and sales force will welcome these advantages:
The big objection to electronic equipment--from the user's point of view--is that if it goes out of order he fezls helpless. But you have a perfect answer when your equipment is made to Alden Standards of Plug-in Unit Construction because they assure DEPENDABLE OPERATION, as follows-
30-SECOND REPLACEMENT OF INOPERATIVE UNITS by plugging in avail. able coded spares. TROUBLE INSTANTLY INDICATED AND LOCATED by monitoring elements assigned to each functional unit.
TECHNICAL PERSONNEL NOT REQUIRED to maintain in operation, due to obvious color coding and fool-proof non-interchangeability of mating components.
TOOLESS MAINTENANCE made possible by patented Alden fasteners and plug. in locking and ejecting devices.
AIRMAIL SERVICE-- Compact functional units practical to send airmail to factory for needed overhaul. UNI -RACK FIELD HANDLING UNIT--groups functional units into stacking cabinets not exceeding one- or two-man handling capacity--go easily through windows, doors.
CONNECT AS FAST AS UNLOADED, by coded non-interchangeable unit cables plugged in between Uni-racks.

SEND FOR FREE 226-PAGE HANDBOOK

This 226-page Handbook describes fully the Alden System of Plug-in Unit Construction and the hundreds of components ready-made and completely tooled to meet your every requirement. It's agold-mine for those designing electronic control equipment that is practical in manufacture; dependable in operation.
REQUEST YOUR COPY TODAY -- SENT FREE!

4 ·

· el

IF YOU WORK WITH ELECTRICAL OR ELECTRONIC CIRCUITS...

News--New Products

These manufacturers have invited PROCEEDINGS readers to write for literature and further technical information. Please mention your I.R.E. affiliation.

((ont

from page 30/1)

Microwave Classes for
Signal Corps by GE
A series of month long classes is being conducted by General Electric Co., to instruct Signal Corps technicians on the installation, operation, and maintenance of microwave relay communications equipment. The company is producing the equipment for the Signal Corps at its Syracuse, N. Y. plant.

WAS MADE TO HELP YOU...
414

A color film with schematic animation and supporting narration ... to help you select connectors engineered to your requirements and operating conditions. Disconnect system? Number of contacts? Voltage? Amperage? These and other factors are covered in this helpful film. In addition you'll learn how the printed Cannon Plug Guide (below) leads you to the right connector for any job. Request your free showing today.

CANNON PLUG GUIDE ... An easy-to-follow graphic aid.
CURRENT CAPACITY and its relation to contact spacing.

.Issisting GE instructor (right rear) Gus Kandaris is J. N. Craver, chief radio engineer for the Signal Corps plant engineering agency, who attended the class to further familiarize himself with the GE equipment.
Junction Transistors
The Receiving Tube Div., Raytheon Manufacturing Co., 55 Chapel St., Newton 58, lass., announces the immediate availability of two P-N-P Germanium Junction Transistors types CK721 and CK722. Although CK722 may be had in production quantities, CK721 will be limited in quantity until April, 1953.
r-

SPACING AND NUMBER of contacts involves many factors.

CANNON ELECTRIC

since 1915
Main office and plant, Cannon Electric Company, Los Angeles 31, California. Factories in Los Angeles, New Haven, Toronto. Representatives in principal cities.

;CI CANNON EVCTRIC

"Contact", a30-minute, 16mm Kodachrome sound picture, costs you nothing except 2-way transportation charges. You furnish sound projector. 24page printed Plug Guide will be furnished for each person viewing film. To avoid delay request your booking for the film on coupon today.
44A

MODERN TALKING PICTURE SERVICE, INC. 45 Rockefeller Plaza, New York 20, N.Y.

NAME

FIRM

DATE TO BE SHOWN

ALTERNATE DATES

ADDRESS

CITY

70NE STATE

DEPT. 0-377

Types CK721 and CK722 are described in data sheets now available from Raytheon's Technical Information Service, or from sales offices in New York City, Chicago and Los Angeles. Both types have noise factors averaging 22 db at 1,000 cps. Type CK721 has an average power gain of 38 db while CK722 averages 30 db. The
units require avolume of 0.03 cubic inches and leads may be soldered or welded into the circuit, or cut for insertion into stand-
ard subminiature sockets.
(Continued on page 454)

PROCEEDINGS OF THE I.R.E.

April, 1953

News--New Products

These manufacturers hava invited PROCEEDINGS readers to write for literature and further technical information. Please mention your I.R.E affiliation.
(Continued from page 44,4)

IF Transformers

Radio Industries, Inc., 5225 N. Ravens-

wood Ave., Ch icago 40, Ill., announces anew

Series "A" design of the "RI-trans" inter-

mediate frequency

transformers, manu-

factured and in use

since 1946.

It is available in

two constructions.

One

long, termi-

nal lugs for conven-

tional wiring and sol-

dering, the other, for

use with the new printed circuit chas-

sis, employing short

terminal lugs for pres-

sure-fitting into the

lug slot openings. The transformers utilize silvered mica

capacitors, with capacity accurately main-

tained, having zero temperature coeffi-

cient; perm tuned, top and bottom, and

bandwidth maintained throughout the

required core adjustment, reinforced one-

piece terminal Iugs; interchangeable, uni-

versal snap-clip mounting; uniform opera-

tion through wide variations of tempera-

ture and humidity, and availability with

one or two internal diode capacitors. Size of the can encasing the new "RI-trans" is

1inch square; standard height is 2inches,

but shorter and longer heights are avail-

able as required.

Static Detector
Keithley Instruments, 3868 Carnegie Ave., Cleveland 15, Ohio, has an improved Model 2005 Static Detector which clips onto a Keithley vacuum tube electrometer, providing a convenient and highly sensitive combination for detecting and locating static charges.

the world's most widely used Electronic Supply Guide

ALLIED'S
236-PAGE 1953 CATALOG

THE WORLD'S LARGEST STOCKS OF ELECTRONIC SUPPLIES FOR INDUSTRY AND BROADCAST STATIONS

-

et-

oil your ·

electronic supplies and equipment. Send your orders to us

at ALLIED--the reliable one-supply-source for all

your electronic needs. Depend on us for the world's largest

stocks of special-purpose electron tubes, test instruments,

audio equipment, electronic parts (transformers,

capacitors, controls, etc.) and accessories--everything for

industrial and communications application, for research,

, development, maintenance and production. We make

immediate shipment from complete quality lines that are

always ;n stock. Send today for your FREE copy of the 1953

ALLIED Catalog--the complete, up-to-date guide to

the world's largest stocks of Electronic Supplies for

Industrial and Broadcast use.

The new electrometer accessory consists primarily of two concentric, telescop-
(Contimied on page 53A)

PROCEEDINGS OF THE I.R.E.

April, 1953

One complete dependable source for everything in electronics

ALLIED RADIO is.D.3 833 W. luckier, Ilvd., Dept.
Chic·g· 7, 1111rsois

It's A Specialized Job...
designing vibrator power supply circuits

To avoid trouble with yours,
Call On MALLORY

Iiyour mobile radio equipment is going to operate properly, under all sorts of conditions, the power circuit must be carefully designed. Experienced engineering must go into the design and selection of each element so the vibrator characteristics are in balance with the transformer and buffer capacitor.
These are some of the reasons vibrators can't be selected simply by size and rating alone if you are going to get long, trouble-free performance.
N1, ehave worked with leading manufacturers of electronic equipment on their vibrator power supply problems since we introduced the first commercial vibrator over 20 years ago. Our experience includes supplying more vibrators for original equipment than all other makes combined.
To avoid vibrator power supply troubles ... call on Mallory in the design stage. Our engineers are thoroughly qualified by experience to study your specifications to be sure the power circuit will give maximum performance.
Our engineers will be glad to discuss your vibrator power supply problems. Write or call us today.
Expect more ... Get more from MALLORY

In addition to supplying vibrators, Mallory is equipped to design and manufacture complete power supply units ... to your exact requirements ...to meet your production schedules.

Parts distributors in all major cities stock Mallory standard components for your convenience

'MALLORY P. R. MAL LORNI CCLInc.

SERVING INDUSTRY WITH THESE PRODUCTS:
Electromechanical --Resistors · Switches ·Television Tuners ·Vibrators Electrochemical--Capacitors ·Rectifiers ·Mercury Dry Batteries Metallurgical--Contacts·Special Metals and Ceramics·Welding Materials

P. R. MALLORY & CO., INC., INDIANAPOLIS 6, INDIANA

46A

PROCEEDINGS OF THE I.R.E.

April, 1953

ry relay...This! New CLARE Type T
6
High Frequency Impulse Relay will follow 2500 cycles per second with
life measured in billions of operations!

specifications....

MECHANICAL

SIZE:

1.15 '16 in. diameter x 2-3/16 in. overall.

WEIGHT:

5 ounces.

MOUNTING: Equipped with mica-filled bakelite plug, to fit a standard 8-pin octal socket.

COVER:

Removable dust-tight cover.

CONTACTS: Type. Material: Gap: Pressure:
COIL: Type: Wire:

Form A (s.p.s.t., normally open) Platinum-iridium 0.0005 inch 30 grams, min. (Coil energized with 50 ampere-turns)
Single winding, bobbin-wound Heavy formex

111EZIEM111111111

COIL DISSIPATION: 0.5 watt (estimated max.)

CONTACT RATING: 0.05 amp., max. 50 volts oc. non-inductive. (estimated)

CONTACT BOUNCE: None

OPERATION:

Pull-in

Drop-out

Pull-in time

Drop-out time

· 15 ampere-turns · 12 ampere-turns · 120 microseconds · 100 microseconds

RATE: Will follow 2500 cycles per second; aperiodit to 1000 cycles per second.
LIFE EXPECTANCY: 5 x 10° operations with zero contact current.
DIELECTRIC STRENGTH: 500 volts, rms.

TYPICAL APPLICATIONS

Coil inductance Coil inductance Coil resistance
Pull-in current Drop-out current
Normal coil current Contact current

· 0.3 hy (contacts open) · 0.35 hy (contacts closed) · 135 ohms · 10 to 12 ma.
· 8 to 10 ma.
· 40 ma. · 0.075 ma.

LIFE EXPECTANCY: Following a 1 s 10° operation run-in period, a life of 5 x 10° operations with a .075 ma. contact load over a 6-month period without readjustment.

View of Clare Type T High Frequency Impulse Relay with dust cover removed

Exterior view of relay ready for mounting

Originally designed for use in an analog computer, the new CLARE Type T High Frequency Impulse Relay is now available for other applications which require ahighly sensitive relay completely free from contact bounce and capable of a prodigious number of operations at extremely high speeds.
Its pull-in time of 120 microseconds and drop-out time of 100 microseconds enable this relay to follow up to 2500 cycles per second; aperiodic to 1000 cycles per second.
In a typical application, it has a life expectancy, following a run-in period of 1x 109 operations, of 5x 109 operations with a 0.75 ma contact load over a6-month period without readjustment.
To achieve its high-speed, no-bounce, and other unusual characteristics, this relay is built to extremely close tolerances, with a high degree of precision, under conditions of utmost cleanliness. This necessitated the development of techniques never before employed in the manufacture of relays.
Even before this first public announcement of the availability of this truly remarkable relay, its fame has spread. Already dozens of inquiries and sample orders have been received from laboratories and development organizations which had learned of its existence through the manufacturer who first applied it in a well-known computer. It may provide the answer to one of your problems.
For full information on this new relay or for consultation on any relay problem, we invite you to contact your nearest CLARE sales engineer or write to C. P. Clare & Co., 4719 West Sunnyside Avenue, Chicago 30, Illinois. In Canada: Canadian Line Materials Ltd., Toronto 13, Ontario. Cable address: CLARELAY.
WRITE FOR BULLETIN 117
GLLYL LLÈ FIRST IN THE INDUSTRIAL FIELD

"Radio" is away of Thinking!

Just as "communication" needed to break its earthbound bonds of wire and take to the air, so industry is seeking and finding in radio controls new "tools" ranging from servomechanisms to electronic computors.

THIS IS NO DREAM
Radio engineers are making the "bright new world" which was the dream of men in World War II. Just as radio engineers bridged the lost silence of the sea by ship radio communications in the 1900s, so these same thinkers, as radio physicists unleashed the "radiation" power of the atom, and will harness it to industry. They have brought the picture of the world under your control by a knob in your home television -- and have beaten the monotony of endless counting by the electronic computer.

TAKING THE GUESSWORK OUT
Such progress is no "happy accident." Men do not "discover" television -- they "engineer" it. A good example is the inevitability of color television. From "fission" to "computation" the job is done by an enormous process of information exchange -- the methodical and brilliant teaming together of engineering thinking to solve a problem. In radio this work has been done deliberately by a growing engineering society, through its meetings and published proceedings, which unleash the minds of men.

In 1952 "Proceedings of the IRE" published 1,792 text pages, exclusive of product news and departmental features. This is the word-count equivalent of seven 500 page textbooks on radio-electronics for engineers, and
exceeds the contents of the next two contemporary publications put together. This "high" in genuine reader service was logically matched by advertising worth half amillion dollars, by firms investing in the engineers' reading interest.

"Proceedings of the I·R·E"
Published by the
INSTITUTE OF RADIO ENGINEERS
Advertising Dept. 1475 Broadway New York 36, N. Y., BRyant 9-7550

Radio
48A

·

Communications

·

Television

·

Electronics

PROCEEDINGS OF THE I.R.E.

April, 1953

Leagues Ahead in Lug Seals
HERMETIC SEALS
with
Attakkt Luq

GROMMETS available in all condenser seal sizes.

... embodying the newest, most advanced features
for every application

1?ROMMETS available in all ondenser seal sizes.

PROCEEDINGS OF THE I.R.E.

HERMETIC has designed a complete
series of hermetic seals with attached lugs as an associated line of the self-lug tubing seals. This series is characterized by innovations of particular interest to design engineers:
· Lugs are affixed by HERMETIC's new positive method and are guaranteed to be secure.
· Lugs are available for every tubular seal and bathtub condenser seal currently used in industry.
· Lugs are available Rotor bent through any angle desired; with pierced holes, or notched for wrap around connection.
· Solder-Lug Feed-Throughs, parts 1503-04-05-06, are also available in this series.

WRITE detailing your
problem for immediate attention, and ask for FREE copy of HERMETIC's informative 32-page brochure, the most complete presentation ever offered on hermetic seals.
0 00 IN ·

HERMETIC SEAL PR(

29 South Sixth Street · Newark 7, New Jersey
FIRST AND FOREMOST IN MI NIATURIZATION
April, 1953

CAPACITOR fetégbelik

Aerovox offers the widest choice of function-fitted*
impregnants. Examples:
For minimum size and average operating conditions, there are several wax impregnating compounds. For minimum weight and size yet providing maximum reliability, there is Hyvol D.
For marked stability and reliability over wide temperature ranges, there is Hyvol M. For utmost dependability under severe operating conditions, there is Aerolene.
For extreme stability, plastic film dielectrics are available. For heavy-duty AC operation, there is synthetic Hyvol F.
Tell us what that capacitor is expected to do. We'll select the impregnant best fitted to that function.

.. A.
guJiem.lyloiel ginl-imp
Aerovox engineers are always ready to study your circuitry, asso cia ted compo nents and operational requireme nts,if you wish. This can mean marked savings in component costs, along with th e best choice of capacitors. Let us tell yo u about it.

dreegmele

AEROVOX CO RPORA7'10N NEW BEDFORD, MASS. H10-:

These 9parts are replaced by this rieer Centralab Printed Electronic Circuit

For scores of applications --Centralab Printed Electronic Circuits assure 6tremendous SAVINGS in design, production and performance

25% to 80% fewer soldered connections

,,de

Fewer pieces to buy or inventory

Fewer connections mina, imize wiring errors

4lower installation cost -- with fewer ports

It Lets weight, less space -- "opens-up -- chassis

6Improved c'rcuit stability from uniform PEC's

ANY way you look at them, Centralab Printed Electronic Circuits mean more money in your pocket. No other modern electronic development offers you six such tremendous time and cost-saving advantages for low-power applications.
Pioneered and completely developed by Centralab, these resistor-capacitor combinations in complete or partial circuits are extremely ecorromical to use. Many times, the first cost of PEC's is less than the components they replace.

As for versatility -- there are more than 30 standard circuits already tooled for you. There is atremendously wide range of sizes and capacities available to you.
If you have aspecial circuit problem, we'll even design custom plates at nominal cost where volume warrants. No wonder 25,000,000 PEC's are in use today! No wonder scores of manufacturers say it's good business to specify and use Centralab Printed Electronic Circuits. Send coupon for full details.

Another Centralab first! NEW PENDET
-- a complete pentode detector and audio coupler circuit that
replaces 9 parts ... eliminates 9 soldered connections.
Talk about compactness--this new Pend« really has it! You get 4 resistors and 5capacitors screened and fired to asingle Ceramic-X plate. It replaces 9 conventional components. Only 9 connections are required instead of the usual 18.
Think what this terrific PEC "package" can do in simplifying installation and cutting manufacturing costs of ac, dc and portable receivers. Get complete information on this new PC-I60 Pendet NOW. Check No. 42 -149 in coupon.

Pendet couples the combination detector and first audio pentode tube to the audio output tube. Plate is only 1-5/16" x 7/8" x 11/64" thick. Leeds are 2-1/2" long. Capacitors are 450 vdcw, 800 vdc test. Resistors are 1/5 watt.

PROCEEDINGS OF THE I.R.E.

April, 1953

A Division of Globe-Union Inc. Milwaukee 1, Wisconsin
In Canada, 635 Queen Street East, Toronto, Ontario
111111111111111111111.1111111181111111B111111111111111111111111111.11111111181111.11.1111111111811111··11·

CENTRALAB, A Division of Globe-Union Inc.

920-D E. Keefe Ave., Milwaukee 1, Wisconsin

Please send the following bulletins: D 42-149, D PEC guide ·

No. 2. 1'd also like a copy of Centralab's new Electronic

Components Catalog No. 28.

na

Name

Position

Company

X Address City

State

naa

1111111XXIIIIIIIIMIXIIIII11111111111111111111111111X1111111111.11.11.1111XXXIIIIRMIIIIIIIII·

51 A

RADIO FREQUENCY CONTROL UNITS

Partial List of Units Manufactured

Bulova Type
70A

Frequency Range

Tot.

6000 KC to 15000 KC

.005%

70C

350 KC to 1100 KC

.03%

70D

200 KC to 500 KC

.01 %

71E

90 KC to 110 KC

.02%

Temperature Range
55 C to +90 C
-40°C to +70°C -- 40 °C to +70'C
-- 40 °C to +70 C

·
FOR THE FIRST TIME EVER... the high-precision
production techniques of fine watchmaking is now being applied to the manufacture of radio frequency control units by Bulova.
·
Inquiries invited on crystals for your special application
·
Quartz Crystal Division
BULOVA WATCH COMPANY, INC.

6 3 0 FIFTH AVENUE, NEW YORK, N. Y.

CIRCLE 5 -7 7 0 0

PROCEEDINGS OF THE I.R.E.

April, 1,),;

News--New Products
These manufacturers have invited PROCEEDINGS readers to write for literature and further technical
information. Please mention your I.R.E. affiliation.
(Continued from page 45.4)
ing tubes and a center aluminum rod. When clipped over the HI terminal of the electrometer, the tubes act as ashield for the rod, limiting sensitivity to a narrow cone along their axis.
Qualitative results are obtained by noting the deflection of the meter pointer. Sensitivity can be varied by extending or lowering the inner tube. With the tube lowered to maximum sensitivity, acharged pocket comb throws the pointer off scale from adistance of ten feet.
Uses for the Electrometer and Static Detector include virtually every application where electrostatic charges are undesirable and an instrument of extreme sensitivity is needed.
Servo Tester
The 101-A Servo Tester designed for the rapid field maintenance and production testing of servo systems is available from Industrial Control Co., Wyandanch, L. I., N. Y. The transient response of the loop under test is shown on a 3-inch cathode-ray screen, and viewed through a mask onto which has been previously drawn the response specified by the manufacturer. The operator adjusts the servo loop to match the two traces; if this is not possible, the loop is declared inoperative and returned to alaboratory area or maintenance depot for repairs.

Meet the Redheads... tops for tape recording

A standard Servo Test receptacle is installed on the equipment to be checked, and wired into the data system in accordance with simple instructions. A single cable connects this plug to the 101-A. Thus the test can be performed in avery short time.
The 10I-A complements the earlier 100-A, designed especially for laboratory servo evaluation. It can be rack mounted into complex servo equipments, where a stand-by checking means is necessary. It can be used with dc and carrier frequency servos, and operates from the 117 volt 60 or 400 cps line.
For further information, contact G. M. Attura. or phone Midland 3-7548.
(Continued ors page 55.4)

See how the latest additions to the Brush family of magnetic recording components can improve your tape recorders!
The BK -1090 record-reproduce head has the standard track width designed for dual track recording on ¼ inch tape. It provides unusually high resolution and uniformity over an extended frequency range. Cast resin construction assures dimensional stability, minimizes moisture absorption, and affords freedom from microphonics. Its balanced magnetic construction, precision lapped gap, Mu-metal housing, and single-hole mounting provide important design advantages.
The BK-1110 erase head has the same basic construction as the companion record-reproduce unit. Its outstanding feature is its efficient erasing at low power consumption--less thanv2voltampere.
Investigate these new "Redheads" for your magnetic recording. Your inquiries will receive the attention of capable engineers. Write Brush Electronics Company, Department F-4, 3405 Perkins Avenue, Cleveland 14, Ohio.

BRUSH ELECTRONICS

INDUSTRIAL AND RESEARCH INSTRUMENTS PIEZOELECTRIC MATERIALS · ACOUSTIC DEVICES
MAGNETIC RECORDING EQUIPMENT ULTRASONIC EQUIPMENT

1.113
AIM
ELECTRONICS

COMPANY
formerly The Brush Development Co. Brush Electronics Company
is an operating unit of Clevite Corporation.

PROCEEDINGS OF THE I.R.E.

April, 1953

53A

'packaged herhiemelleg power supplies iinkdeel,llolnas

American Electric supplies these complete, "packaged unit" power supplies for all high frequency requirements. Noted for their rugged, reliable performance, the amazingly low maintenance factor of American Electric alternators results from aunique and exclusive design principle: arotating inductor without coils; without springs, slip rings or brushes! Nothing to wear out, nothing to service ... as maintenance-free as its two sealed ball bearings!

The No. 90281
High Voltage Power Supply
The Na. 90281 high voltage power supply has o d.c. output of 700 volts, with maximum current of 250 ma. In addition, AC filament power of 6.3 volts at 4 amperes is also availoble so that this power supply is an ideal unit for use with transmitters, such as the Millen No. 90800, as well as general laboratory purposes.
The power supply uses two No. 816 rectifiers and has o two section r filter with 10 henry General Electric chokes and a 2-2-10 mfd. bank of 1000 volt General Electric Pyranol capacitors. The panel is standard 81/ 4 " x 19" rack mounting.
JAMES MILLEN
MFG. CO., INC.
MAIN OFFICE AND FACTORY
MAIDEN
MASSACHUSETTS

f
Semi-portable, skid-mounted missile launching power supply completely weather protected.
Portable, caster·mounted 400 cycle installation for production test equipment.
Stationary installation, nec belt drive, resilient mounted for laborotory h.f. test equipment.
Variable frequency installation for research test work.
Manufacturers Also of Miniature A.C. (All Frequencies)
Electric Drive Motors, Blowers and Fons

Correct Power Supply for Every Installation
Portable., Sc' iii-port able or stationary types, open models or completely enclosed for weather protection. Caster or pneumatic tire mounts, skid mounts and resilient rubber mounts on stationary types.
Wide Frequency Ranges
Fixed Frequencies from 250 cycles to 2400 cycles (up to 4000 cycles in the lower ratings). Variable Frequencies from 380 cycles to 1200 cycles and 1200 cycles to 2400 cycles. Excellent Voltage Regulation: Standard -± 1% to as low as ± .5% depending upon choice of drive. Electronic regulators or magnetic amplifier regulators supplied. Motor Drives--Common shaft,direct connected, Vee belt or positive, no-slip timing belt types. Variable speed on variable frequency models. Low Harmonic Content
Less than 2% on single phase. less than 1% on three phase. Exceedingly low harmonic content results directly from alternator design without use of filters. Output Ranges single phase-500 watts to 15 KVA three phase-500 watts to 30 KVA (outputs up to 75 KVA available in other alternator designs.)
WHATEVER YOUR GROUND POWER SUPPLY REQUIREMENTS
Ask American Electric for quotation
NOW! Ask for Details!
American Electric Auxiliary Airborne MISSILE POWER SUPPLIES
4811 Telegraph Road,
Los Angeles 22,
California I

PROCEEDINGS OF THE I.R.S.

April, 1953

News--New Products
These manufacturers have invited PROCEEDINGS readers to write for literature and further :.echnical information. Please mention your I.R.E. affiliation.
(Continued from page 53A)
Miniature Power Supply
The Airpax Products Company, Middle River, Baltimore 20, Md., has released the first of a series of miniaturized dc to dc power supplies using their high-frequency vibrator, 450 cps in illustration.
The total weight of the new item, Model A-1220, is 1pound 14 ounces. Vibrator and power supply are hermetically sealed, vibrator attaches with snap fasteners. Output of 150 volts, 100 ma, is filtered to 1per cent peak ripple. Three standard units of 6, 12, and 26.5 vdc input are offered. On special order output power up to 20 watts, output voltages up to 300 volts, and input between 4 and 100 vdc can be furnished.
Unit is designed to meet severe military standards of vibration, shock, temperature range, humidity, and altitude.
Hermetically-Sealed Accelerometer
The G. M. Giannini Co., Inc., 117 E. Colorado St., P.O. Box N, Pasadena 1, Calif., and East Orange, N. J., announces a new, long-life accelerometer, Model 24132. Smallness and compactness are noteworthy features of this instrument, which utilizes a potentiometer resistance and is hermetically sealed in an inert gas. It has low, natural frequency and in most cases alarge output requiring no amplifying unit.

9 N
o
usual

ATR
V

autoradio

o
rlar, CUAP·riii.
mum sues. Iwas a
lliBRAiORS

have

ceramic

stack spacers

A COMPLETE LINE OF VIBRATORS

Model 24132 is obtainable in resistance ranges from 1,000 to 20,000 ohms and for any accelerometer measurement up to 300 with special adaptations possible. Potentiometer element safely carries current up to 10 ma. The 24132 has good resolution with 0.25 per cent minimum offered on the standard instrument, is a1per cent instrument in performance and has a good life expectancy under vibration. Optimum operation between --54°C and +71 °Cis obtained. Damping is 0.5 ±0.075 of critical for a 7.5G instrument as a typical case. A special shipping stop may be obtained for increasing instrument life, and the instrument is magnetically damped. Designed for applications in computing, telemetering and aircraft and missile control.
(Continued on page 1144)

PROCEEDINGS OF THE 1.R.E.

April, 1933

Designed for Use in Standard Vibrator-Operated Auto Radio Receivers. Built with Precision Construction, featuring Ceramic Stack Spacers for Longer Lasting Life. Backed by more than 22 years of experience in Vibrator Design, Development, and Manufacturing.

sod s ors11.5

taw 0151 045

tom Weenie'

"A" Battery Eliminators, DC-AC Inverters, Auto Radio Vibrators
See eves Ida« evs eterete `teceasy
AMERICAN TELEVISION &RADIO CO. 2ualit9 P'roduces Sc.tee 1931 SAINT PAUL 1, MINNESOTA--U. S. A.

a direct-reading 0-42 megacycle FREQU EN CY METER
the Berkeley Model 5510

-Wr
A TRUE
ELECTROSTATIC VOLTMETER

Model 5570 is asingle, compact instrument for rapid, precise measurement of frequencies from 0cps to 42 mc. Basic sections are (1) a high-speed events -per-unit-time meter (EPUT), and (2) a heterodyne unit. Frequencies of 2 mc and below are applied directly to the EPUT and are read on the last six decade panels. From 2 to 42 mc, frequencies are applied to heterodyne unit and selector knob turned until output meter indicates the proper harmonic has been selected. External adjustment of crystal control unit to WWV is provided, to obtain an accuracy of 1part in 107,--i- 1count.
applications
Rapid, accurate transmitter monitoring, crystal checking, general laboratory and production line frequency determination. Addition of a Berkeley Digital Recorder will provide an automatic printed record of the last 6digits; ideal for plotting frequency drift or indicating stability.
specifications

1

RANGE: 0 cycle to 42 megacycles

ACCURACY:

1count, ± crystal accuracy (short term: 1 port in 107)

POWER REQUIREMENTS: I 117 volts, ± 10%, 60 cps, 260 watts

INPUT REQUIREMENTS:

Approximately 1 volt rms. (50 ohm impedance)

DISPLAY TIME:

1 to 5 seconds cont0i0nu2ou0s.l0y2,va0r.2iaablned 2 seconds

TIME BASE: DIMENSIONS:
PANELS

0 .00002, 0.00, U. I Approximately 32" high x21" wid e x 16" deep
I Two 83/4 " x 19"; one 12 1/4 " x 19"

ACCESSORIES:

Available soon to extend range to 160 mc.

PRICE: I $1990.00, F.O.B. Richmond, Californio

1 Prices and Specifications subject to change without notice.

This instrument permits voltage readings on AC or DC circuits of very high resistance. The only current drawn is the very small leakage current and a very low capacitance current on AC circuits. Very useful for the many high voltage--low current circuits employed in nuclear research. Available with full scale voltages ranging between 300 and 3500 volts. Special laboratory instrument available with full scale reading of 150 volts. Full scale capacitance ranges from 8 mmfds for the 3500 volt model to 100 mmfds for the 150 volt instrument.Magnetic damping. 21/ 2 "dial. Write for complete specifications.

7

· Please Request Bulletin 204

Bwilereleit Scieetlec,

division of BECKMAN INSTRUMEN'TS INC. 2200 WRIGHT AVENUE · RICHMOND, CALIFORNIA
"DIRECT READING DIGITAL PRESENTATION OF INFORMATION"
51) \

FERRANTI ELECTRIC, INC.
30 Rockefeller Plaza · New York 20, N. Y
FERRANTI, LTD., Hollinwood, England FERRANTI ELECTRIC, LTD., Toronto, Canada

PROCEEDINGS OF TIIE

.·11eil. 1953

ANOTHER
4241C FIRST!

New Ceramic
DISCAPS .
Designed for AC Line By-Pass Applications

Underwriters' Laboratories specify that a ceramic capacitor used in AC line by-pass applications must withstand a 1500 volt AC 60 cycle one minute test.
RMC has developed Type UL DISCAPS for this or any application where a steady or intermittent higher voltage may occur. Capacities between .001 MFD and .02 MFD are now in production.
The use of Type UL Discaps will effect considerable cost savings over any other type of capacitor acceptable to the Underwriters' Laboratories.

Two New Developments from the
RMC Techfiical
Ceramic Laboratories

NEW
HIGH VOLTAGE DISCAPS DESIGNED FOR 90° DEFLECTION YOKES
Designed especially for 90 deflection yokes, these RMC DISCAPS are rated at 2000, 3000, 4000, and 5000 volts DC.
The voltage safety factor required in this application is insured when DISCAPS are used. Now available in any capacity between 15 MMF and 240 MMF, their smaller size and lower initial cost offer definite production ease and overall savings.

SEND FOR SAMPLES AND TECHNICAL DATA

DISCAP CERAMIC CONDENSERS

PROCEEDINGS OF THE IRE.

ltril, 1953

RADIO MATERIALS CORPORATION
GENERAL OFFICE: 3325 N. California Ave., Chicago 18, III.
FACTORIES AT CHICAGO, ILL. AND ATTICA, IND. DISTRIBUTORS: Contact Jobber Sales Co., 146 Broadway, Paterson 1, N. J.

Q

ADJUSTABLE RESISTORS

FOR CRITICAL ELECTRONIC REQUIREMENTS

If your electronic circuits require a noiseless, adjustable resistor with long life and permanent characteristics ... if you need a rheostat or potentiometer which is unaffected by heat, cold, moisture, or hard use ... the Allen-Bradley Type JBradleyometer is the logical answer.
It is not a film or paint type resistor. The molded resistor does not become noisy with age. The carbon contact brush actually improves with use. Type J Bradleyometers are available in single, dual, and triple unit assemblies.
Allen-Bradley Co., 114 W. Greenfield Ave., Milwaukee 4, Wis.

ANY RESISTANCEROTATION CURVE
Prior to molding, the composition of the resistor ring may be varied to produce any resistance-rotation curve. After molding, the resistance is permanently fixed. There are no soldered connections. Shaft, faceplate, and other ferrous parts are stainless steel.
58A

ALLEN-BRA DLEY
FIXED & ADJUSTABLE RADI RESISTORS
of radio and electronic equipment

PROCEEDINGS OF THE I.R.E.

April, 1953

Have you heard the latest... IN BACKGROUND MUSIC?

For further information, write to Dept. G1218A
AMPEX
rMAGNETIC RECORDERS

PROCEEDINGS OF THE I.R.E.

April, 19.53

An atmosphere to relax and enjoy--or the stimulation to work, to think, to play or buy -- these are the benefits of background music. And background music is now practical anywhere, even beyond the reach of present wired services.
With the announcement of the new AMPEX 450, magnetic tape, musical wonder of a coming era, has become the ideal medium for background music. Hourly cost drops to a new low; quality rises to an all-time high. A wide variety of music for every purpose is now available on pre-recorded tape (see your Ampex distributor). Tape recordings eliminate needle scratch and their fidelity is permanent. They last for any conceivable number of plays.
On the AMPEX 450, up to eight hours of unrepeated music is available from one 14-inch reel of tape, and fully automatic repetition is available. The troubles and complexities of record changers are eliminated. And the AMPEX requires no standby attention from an operator.
AMPEX background music has aplace in your business.

THE NEW AMPEX 450
·8 hours of uninterrupted music (rest periods as desired)
·Usable on land, sea or air ·No standby operator required ·Lowest cost per hour

AMPEX ELECTRIC CORPORATION
934 CHARTER STREET · REDWOOD CITY, CALIF.

59A

Up-to-date news of every British development

WIRELESS WORLD. Britain's chief technical magazine in
the general field of radio, television and electronics. Founded over 40 years ago, it provides acomplete and accurate survey of the newest British techniques in design and manufacture. Articles of a high standard cover every phase of radio and allied technical practice, with news items on the wider aspects of international radio. Theoretical articles by recognised experts deal with new developments, while design data and
circuits for every application are published. WIRELESS WORLD
is indispensable to technicians of all grades and is read in all parts of the world.
Published monthly, >44.50 ayear.

WIRELESS ENGINEER -- the magazine of radio research
and progress -- is produced for research engineers, designers and students in the fields of radio, television and electronics. Its editorial policy is to publish only original work, and its
highly specialized content is accepted as the authoritative source of information for advanced workers everywhere. The magazine's Editorial Advisory Board contains representatives of the National Physical Laboratory, the British Broadcasting Corporation, and the British Post Office. Regular features include an Abstracts and References Section compiled by the Radio Research Organisation of the Department of Scientific and Industrial Research.
Published monthly, ,-·',7.00 ayear.

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PROCEEDINGS OF THE I.R.E.

April, 1953

Bring your tough problems to us at
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If standard, mass-produced transformers won't do for your product or application, consider this ...
Since 1938 we've concentrated exclusively in the specialized field of CUSTOM-DESIGNED and CUSTOM-BUILT Transformers for government and industry.
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PROCEEDINGS OF TI1E IRE.

April, 1955

ildred

NEW
5KW at 900 MC GL-6182
"Custom-tailored" for military communications and medium-power TV transmitters!
Compact. Only 8 5/16" high! One tube handles all military and TV frequencies, 200 to 900 mc.
Tetrode design assures low drive requirement.
Modern ceramic construction and ring-seal design.
Quickly installed or removed. Spring-finger electrical contacts; convenient, firm-grip handle. Tube weighs only 2 pounds!

U-H-F DESIGNERS: this 5-kw tetrode is the power tube you've been waiting for! Provides ample r-f for your new medium-power transmitter, efficiently, with economy--takes up
minimum space, is lightweight and easy to plug in. A tube that maintenance-conscious. operators will welcome! ...Military commu-
nications and radar--industrial dielectric heating--u-h-f TV--these are leading applications. Get ratings and the full tube story in special G-E Bulletin ETD-726. Write Tube Department, General Electric Company, Schenectady 5, N. Y.

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The etched surface on the faceplate of the metal-shell picture tube (right) diffuses the reflection from the lighted match--while the untreated faceplate of the other tube "mirrors" it.
Here is the answer to an awkward problem ... and RCA metal-shell kinescopes solve it simply. They suppress bothersome reflections from room lights and other bright objects. And they reproduce clear, graphic pictures over the entire faceplate area.

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For technical data or design help, write RCA Commercial Engineering, Section 47DR. Or just call your nearest RCA Field Office:
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HARRISON, N.J.

64A

BOARD OF DIRECTORS, 1953
J. W. McRae President
S. R. Kantebet Vice-President
W. R. G. Baker Treasurer
Haraden Pratt Secretary
Alfred N. Goldsmith Editor
I. S. Coggeshall Senior Past President
D. B. Sinclair Junior Past President
1953
R. D. Bennett G. H. Browning (121)
W. H. Doherty A. W. Graf (R5) W. R. Hewlett A. V. Loughren R. L. Sink (R7)
G. R. Town Irving Wolff (R3)
1953-1954
J. T. Henderson (R8) C. A. Priest (R4)
J. R. Ragazzini (R2) J. D. Ryder
A. W. Straiton (R6) Ernst Weber
1953-1955
S. L. Bailey B. E. Shackleford
·
Harold R. Zeamans General Counsel
·
George W. Bailey Executive Secretary
Laurence G. Cumming Technical Secretary
·
Changes of address (with advance notice of fifteen days) and communications regarding subscriptions and payments should be mailed to the Secretary of the Institute, at 450 Ahnaip St., Menasha, Wisconsin, or IEast 79 Street, New York 21, N. Y.
All rights of publication including translation, into foreign languages, are reserved by the Institute. Abstracts of papers with mention of their source may be printed. Requests for republication privileges should be addressed to The Institute of Radio Engineers

PROCEEDINGS OF THE I.R.E.*
Published Monthly by
The Institute of Radio Engineers, Inc.

1

VOLUME 41

April, 1953

N UMBER 4

PROCEEDINGS OF THE I.R.E.

John Tasker Henderson, Director, 1953-1954

450

The Engineer: Expert or Citizen?

Arthur V. Loughren 451

4532. Radio Progress During 1952 4533. Correction to "Hall Effect"

452 Olof Lindberg 507

4534. Standards on Sound Recording and Reproducing: Methods of

Measurement of Noise, 1953

508

4535. Reliability of Airborne Electronic Components B G. Bromberg and R. D. Hill, Jr 513

4536. Fluctuation Noise in aMicrowave Superregenerative Amplifier Theodore S. George and Harry Urkowitz 516

4537. The Use of Admittance Diagrams in Oscillator Analysis Herbert J. Reich 522

4538. Transfer Characteristics and Mu Factor of Picture Tubes Kurt Schlesinger 528

4539. Optimum Linear Shaping and Filtering Networks Raymond S. Berkowitz 532

4540. Determination of Voltage, Current, and Magnetic Field Distributions together with the Self-Capacitance, Inductance and HF Resistance of Single-Layer Coils.. Abd El-Samie Mostafa and M. K. Gohar 537

Correspondence:

4541. a'1 nstantaneous' Frequency"

Jacob Shekel 548

4542. "More on Direction Finders"

H. G. Hopkins 548

4543. "The Geographical and Height Distribution of the Gradient of Re-

fractive Index"

Bradford R. Bean 549

Contributors to the PROCEEDINGS OF THE I.R E

550

INSTITUTE NEWS AND RADIO NOTES SECTION

Technical Committee Notes

552

Professional Group News

553

1953 I.R.E. Convention Record

554

IRE People

556

Books: 4544. "High Frequency Transmission Lines," by J. de France
Reviewed by A. G. Clavier 558

4545. "Handbook of Engineering Fundamentals," edited by Ovid W.

Eshbach

Reviewed by Albert Preisman 558

4546. "Theory of Electromagnetic Waves, A Symposium Sponsored by

the Geophysical Research Directorate, Air Force Cambridge Re-

search Laboratories, and the Institute for Mathematics and Me-

chanics, New York University"

Reviewed by George Sinclair 558

4547. "Radio Spectrum Conservation, A Report of the Joint Technical Advisory Committee, IRE-RTMA" Reviewed by Edward W. Allen, Jr. 558

4548. "The Oxide-Coated Cathode Volume One--Manufacture," by G.

Herrmann and S. Wagener.

Reviewed by George D. O'Neill 559

4549. "Dictionary of Conformal Representations," by H. Kober Reviewed by Harold A. Wheeler and Walter K. Kahn 559

4550. "TV Troubleshooting and Repair Guide Book Volume I," by

Robert G. Middleton

Reviewed by Kenneth Fowler 560

4551. "Advances in Electronics, Volume IV," edited by L. Marton.... Reviewed by Paul K. Hudson 560

4552. "The Electromagnetic Field," by Max Mason and Warren Weaver. Reviewed by Ernst Weber 560

4553. Abstracts and References

561

Meetings with Exhibits

lA Student Branch Meetings

86A

News--New Products

30A Membership

93A

Industrial Engineering Notes 66A Positions Open

126A

Section Meetings

81A

Positions Wanted

134A

Advertising Index

166A

Copyright 1953, by The Institute of Radio Enemas., lose

EDITORIAL DEPARTMENT
Alfred N. Goldsmith Editor
E. K. Gannett Administrative Editor
Manta D. Sands Assistant Editor

·
ADVERTISING DEPARTMENT William C. Copp Advertising Manager Lillian'Petranek Assistant Advertising Manager

· 0.
BOARD OF EDITORS
Alfred N. Goldsmith Chairman

PAPERS REVIEW

COMMITTEE

a

George F. Metcalf

Chairman

ADMINISTRATIVE COMMITTEE OF THE BOARD OF EDITORS
Alfred N. Goldsmith Chairman

a
Reg. U. S. Pat. Off.
Responsibility for the contents of papers published in the
PROCEEDINGS OF THE I.R.E. rests upon the authors.
Statements made in papers are not binding on the Institute
or its members.

450

PROCEEDINGS OF THE I.R.E.

April

John Tasker Henderson

DIRECTOR, 1953-1954

J. T. Henderson was born on December 9,1905, in Montreal, Canada. He received the B.S. and M.S. degrees in engineering physics at McGill Uni-
versity in 1927 and 1928, respectively, and the Ph.D. degree from the University of London in
1932. He carried out ionospheric experiments during the total solar eclipse in Canada in 1932, and studied further in Munich, Germany until 1933.
In 1933 Dr. Henderson joined the staff of the National Research Council of Canada in Ottawa. As head of the radio section he participated in direction-finding experiments on atmospherics in Ontario and Manitoba which gave rise to the de-
velopment of a shortwave cathode-ray direction
finder, widely used by the Royal Canadian Navy during World War II.
In 1939 Dr. Henderson represented Canada at the first official disclosure of British radar to the
Commonwealth countries. He returned to Ottawa to start similar work at the Council, directed the development of radar equipment for the Armed Services, and contributed in organizing the radar division of Research Enterprises Limited, aCrown
company for quantity manufacture of the Coun-

cil's wartime developments. From 1942-1946 Dr. Henderson served as an officer in the Royal Canadian Air Force, where he was concerned with the installation and operation of the early warning radar chain in Nova Scotia, Newfoundland, and Labrador. He later served overseas.
Returning to the National Research Council, Dr. Henderson was the Canadian Delegation's scientific advisor to the United Nations Atomic
Energy Commission. Back in Ottawa, he headed a group studying the application of radar to sur-
veying, and succeeded in evolving methods now used extensively in northern Canada by the Dominion Geodetic Survey and Royal Canadian
Air Force. In 1949 he took charge of the Council's electricity laboratory to expand its scope and set
up new absolute electrical standards for Canada, in conformity with international agreements.
Dr. Henderson joined the Institute in 1928 as an Associate, became a Senior Member in 1947,
and was elected Fellow in 1951. A member of the IRE Ottawa Section, he was Vice-Chairman in 1949-1950 and Chairman in 1950-1951. He is Director of IRE Region 8.

1953

PROCEEDINGS OF THE I.R.E.

451

The Engineer: Expert or Citizen?
ARTHUR V.LOUGHREN
The activities and position of the engineer in a modern community have steadily become wider and more important. It has been found that the engineer is valuable in the civic sense both as an informed citizen and as one who is specially qualified to carry out an approved project. This dual function of the engineer is capably analyzed in the following guest editorial by a leading engineer who is a Fellow and Director of the Institute, and who is also Director of Research of the Hazeltine Corporation.--The Editor.

When the tool of specialization first became important in man's affairs it brought with it the concept of the specialist or expert, as distinct from the nonexpert, or perhaps we should say citizen. It became apparent that to make best use of experts they should be consulted in that capacity with respect only to questions which fell clearly within the field of their expertness. Their views on other questions were valuable, but no more so than the views of any other citizen.
The questions with respect to which the views of experts are particularly helpful are questions of such nature as, "how do we best accomplish this result?" It is implied here that the result to be achieved has been stated already and that the expert is consulted to find how best or most readily lo achieve it. The result (the end desired) is a matter which in a democratic society should be selected by the majority vote of the citizens. There are no experts on such questions as, "are technicolor movies more pleasing than steak dinners?" Broadly, then, the collective voice of the citizens should choose the ends to be sought, and the advice of experts should be obtained in selecting the means by which to achieve those ends.
Many of our politically troublesome problems would be simple if we could get, case by case, a popular verdict on the end to be sought, and then
separately get the advice of recognized experts on the means best calculated to achieve that end. Practically, however, the questions presented for solution often contain means and ends intermixed.

In this kind of circumstance apublic decision for aproposal may register correctly the public's preference for one end as opposed to another, but may
accompany it with the prescription that an expensive and otherwise undesirable method be used. The special pleaders, those grinding their own personal axes or grinding for afee the axes of others, do their best to obtain decisions favorable to them from the public by exploiting this kind of confusion.
In this own field the engineer is always in the position of the expert. In addition to having made him an expert in that field, his training also has
impressed on him the importance of thinking clearly, of discarding the irrelevant, of deciding questions of means only with reference to their effect on the cost of reaching the intended end; it perhaps also has made him a better citizen, one better qualified to separate questions of means from question of ends in fields other than his own, even though in these other fields he cannot play properly the role of expert.
In the light of these considerations, one may ask, "should the engineer take active interest in the political life of his community, his state, his nation?" Of course he should, and on two separate planes. He should serve as expert with respect to the questions where his expert knowledge is appropriate, and, even more importantly, he should. serve as a serious and intellectually able citizen joining with his fellow citizens in selecting the
ends to be sought.

452

PROCEEDINGS OF THE I.R.E.

April

Radio Progress During 1952*

Introduction

THE SMALLER NUM BER of engineering graduates from our colleges, partly resulting from published fears of a predicted overabundance in the

immediate post World War II period, combined with a

greater-than-average increase in the need for engineers,

produced aserious shortage. Whereas, it was anticipated

that the termination of the war would release engineers

to civilian pursuits, the needs of the military in Korea

and the general rearmament program that is now in full

operation, delayed a return to a normal peacetime

economy.

.

Despite the reduced number of graduates, a larger

proportion of engineers are required for production,

maintenance, and operation, services that previously

got along without them. In part, these assignments stem

from the increased emphasis placed on guaranteed re-

liability of electronic equipment when operated in an

unfavorable and hazardous environment.

Industrywide committees were set up to co-operate

with the users of equipment, both military and civilian,

to examine causes of failures and to recommend reme-

dies to assure trustworthy operation. The basic design

of tubes and their circuits, components, assemblies, in-

stallations, and maintenance are all significant elements

in this search for predictable reliability.

The transistor is emerging from the laboratory with

admirable promptness. Much has been done on methods

of producing junction transistors in commercial quan-

tities. Most of the output is going to the armed services,

who are responsible for the contracts under which the

production techniques are being developed.

The Federal Communication Commission in the

United States resumed the licensing of television broad-

casting stations, which was interrupted in 1948. Many

licenses were issued for operation in the band from 470

to 890 mc and one of these uhf stations went on the air

using an existing experimental transmitter. The prob-

lems of adapting standard vhf television receivers for

operation in this higher frequency band received much

attention in anticipation of the early installation of

many such transmitters throughout the country in

places already being served by vhf stations.

The reception of weak but steady uhf waves at dis-

tances greatly exceeding those predicted by accepted

propagation theories presented another of the unex-

pected challenges that have characterized this field over

the years.

*Decimal classification: R090.1. Original manuscript received by the Institute, January 26, 1953. This report was prepared by the 1952 Annual Review Committee of The Institute of Radio Engineers.

Electron Tubes and Semiconductors

Small High-Vacuum Tubes

Diodes: The transit-time spread due to difference in

initial velocity in aplanar diode was calculated for the normal diode and for the diode with reflected beam.

(1)

J. T. Wallmark, "Influence
transit time in diodes," Jour.

oAfppitni.tiPalhysv.el,ocviotli.es23,onppe.le1c0t9r6o-n

1099; October, 1952.

The anode current of asaturated diode is very sensitive to changes in filament current. The time response of the diode is important in incremental ammeters and servomechanisms where the diode is used as an element responsive to current changes of small amplitude. The factors determining the time response for small changes in filament voltage or current were investigated and procedures were described for calculating and for measuring its value.
(2) F. M. Hibberd, "The transient behaviour of thermionic filaments with temperature limited emission," Jour. Sci. Instr., vol. 29, pp. 280-283; September, 1952.

Triodes and Tetrodes: With regard to triodes and tetrodes of the conventional negative-grid type, the development effort continued to be directed toward the attainment of higher power in the vhf and uhf regions with the requirements of television transmission the principal objectives.
Three papers on developmental tubes discussed specific features enabling improved performance at the desired frequencies. Power outputs ranged from a few watts to 50 kw.
(3) D. C. Roger, "Triode amplifiers for operation from 100 to 420 megacycles," Elec. Commun., vol. 29, pp. 12-19; March, 1952. Also Jour. Brit. I.R.E., vol. 11, p. 569; December, 1951.
(4) P. T. Smith, "Some new uhf power tubes," RCA Rev., vol. 13, pp. 224-238; June, 1952.
(5) R. H. Rheaume, "A coaxial power triode for 50 kw output up to 110 mc,» PROC. I.R.E., vol. 40, pp. 1033-1037; September, 1952.

Methods were derived for more accurate calculation of the characteristics of planar triodes under conditions of anonuniform field along the cathode due to the finite pitch and diameter of the grid wires.
(6) W. Dahlke, "Grid effective-potential and cathode-current density of a plane triode under conditions of 'Inselbildung'," Telefunken Zeitung, vol. 24, pp. 213-223; December, 1951.
(7) W. Dahlke, "Calculations of characteristics families for the planar triode with a negative control grid of round parallel wires of finite thickness and pitch," Telefunken-Zeitung, vol. 25, pp. 83-92; June, 1952.

Three papers dealt with more general problems: one on the use of thoriated filaments, another on the magnetic effects of filament current, and the third on evaporation cooling.

1953

Radio Progress During 1952

453

(8) R. B. Ayer, "Use of thoriated tungsten filaments in high power transmitting tubes," PROC. I.R.E., vol. 40, pp. 591-594; May, 1952.
(9) A. M. Hardie, "Magnetron effect in high power valves," Wireless Eng., vol. 29, pp. 232-245; September, 1952.
(10) C. Beurtheret, "Evaporation-cooled power tubes," Electronics, vol. 25, pp. 106-107; March, 1952.
A theory of microwave amplifier tube design was derived including parasitic capacitances and ohmic losses in the leads. The maximum-frequency limit for amplification was calculated to occur when the useful electrode areas are so chosen that the useful capacitance equals the parasitic capacitance.
(11) G. Diemer and K. Rodenhuis, "Optimum geometry of micro-
wave amplifier valves," Philips Res. Rep., vol. 7, pp. 36-44; February, 1952.
A high-gm tube was developed based on the new principle of the space-charge deflection of abeam. The beam can fall either or both of two anodes, depending on the amount of beam deflection, which is in turn determined by the action of a conventional grid. The advantages found are high g,,, without increase of noise level.
(12) J. 'I'. Wallmark, "An experimental high-transconductance tube using space-charge deflection of the electron beam," PROC. I.R.E., vol. 40, pp. 41-48; January, 1952.
Tube Reliability: Tube failures in computing equipment represent amajor problem in their field. The common causes of tube failures were discussed, with the conclusion that low plate current and defective cathodes accounted for about two-thirds of all tube failures in service.
(13) J. A. Goetz and A. W. Brooke, "Electron tube experience in computing equipment," Elec. Eng., vol. 71, pp. 154-157; February, 1952.
A definition of tube reliability was proposed and the 3teps currently being taken to improve reliability were enumerated. Improvements in mechanical design and in manufacturing techniques were described. Methods of testing including vibration, resonance, shock, fatigue, and life were described.
(14) E. G. Rowe, "Technique of Trustworthy Valves," Jour. Brit' I.R.E., vol. 11, pp. 525-540; November, 1951. See also: Elec Commun., vol. 28, pp. 257-275, December, 1951; PROC. I.R.E. , vol. 40, pp. 1166-1177, October, 1952; and Wireless World, vol. 58, pp. 105-108, March, 1952.
It was urged that specifications for reliable tubes should define the tube so that tubes manufactured in accordance with such specifications will give the equipment designer and users of equipment the utmost in reliability.
(15) C. R. Knight and K. C. Harding, "General considerations in regard to specifications for reliable tubes," PROC. I.R.E., vol. 40, pp. 1207-1210; October, 1952.
Continued emphasis was placed on the problems involved in producing reliable tubes for military use.
(16) M. A. Acheson, "Tube reliability from the tube manufacturer's viewpoint," SyIv. Tech., vol. 5, pp. 34-35; April, 1952.
Cathodes: Shifts in the characteristic parameters were observed in oxide-coated-cathode tubes. Studies showed that these shifts were due to cathode interface resistance and to changes in contact potential.

(17) W. B. Bartley and J. E. White, "Characteristic shifts in oxide cathode tubes," Elec. Eng., vol. 71, p. 496; June, 1952.
A study was reported of decay and recovery of the pulsed emission of cathodes of BaO on nickel. Decay was found to be afunction of aging, duty cycle, voltage, and cathode temperature.
(18) R. M. Matheson and L. S. Nergaard, "The decay and recovery
of the pulsed emission of oxide-coated cathodes," Jour. Appt.
Phys., vol. 23, pp. 869-875; August, 1952.
A study of continuous and pulsed emission on oxidecoated cathodes with different base metals was made at low cathode temperatures and showed essentially the same results at cathode temperatures below 650°K. Base metals were afactor in life and initial performance.
(19) F. A. Horak, "Correlation of dc and microsecond pulsed emission from oxide coated cathodes," Jour. Appt. Phys., vol. 23, pp. 346-349; March, 1952.
Measurements of the conductivity of a (BaSrCa)0 emitter over arange from room temperature to 1,100°K indicated the existence of two conduction mechanisms at high and low temperatures. The results were in agreement with the Loosjes-Vink pore-conduction hypothesis.
(20) R. C. Hughes and P. P. Coppola, "Conductivity of oxide emitters," Phys. Rev., vol. 88, pp. 364-368; October 15,1952.
Calculations were made of the conditions under which pore conduction will modify the total conductivity of an oxide-coated cathode.
(21) E. B. Hensley, "On the electrical properties of porous semi-
conductors," Jour. Appt. Phys., vol. 23, pp. 1122-1129; Octo-
ber, 1952.
A study made of thermoelectric power, electrical conductivity, and thermionic emission on BaO and (BaSr)0 oxide-coated cathodes showed results not explainable by simple semiconductor theory, but in good agreement with the pore-conduction hypothesis.
(22) J. R. Young, "Electrical conductivity and thermoelectric power of (BaSr)0 and BaO," Jour. Appl. Phys., vol. 23, pp. 1129-1138; October, 1952.
A tube was constructed in which crystal size of the cathode coating could be measured by X-ray diffraction methods through thin mica windows. The relation of crystal size of barium-strontium oxide to the thermionic emission was studied over arange of temperatures.
(23) E. Yamaka, "A study of the oxide-coated cathode by X-ray
diffraction method (I)," Jour. Appt. Phys., vol. 23, pp. 937-
940; September, 1952.
An extensive review of the practice and theory of oxide-coated cathodes was published in book form.
(24) G. Herrman and S. Wagener, "The Oxide-Coated Cathode," vol. 1, Manufacture, vol. 2, Physics, Chapman and Hall, London; 1951.
A study of the effects of impurities in the nickel base metal of an oxide-coated cathode showed both the dc and pulsed emission to be affected. The impurities studied were Mn, Al, Mg, and W. It was reported that all of the impurities caused interface layers that, with the exception of W, were detrimental to emission.

454

PROCEEDINGS OF THE I.R.E.

April

(25) H. A. Poehler, "The influence of the core material on the thermionic emission of oxide cathodes," PROC. I.R.E., vol. 40, pp. 190-196; February, 1952.
A new dispenser-type cathode known as the Lcathode was compared with three common types of emitters. The efficiency of the L cathode was between that of the oxide cathode and thoriated tungsten. The principal advantages of this cathode were stated to be the accuracy of machined surfaces and spacings obtainable for microwave tubes.
(26) G. A. Espersen, "The L-cathode structure," PROC. I.R.E., vol. 40, pp. 284-289; March, 1952.
Changes in cathode emission were observed in oxide cathodes when tubes were subjected to impact shock. The effect was attributed to agas evolution from various elements during impact.
(27) D. O. Holland, 1. E. Levy, and H. J. Davis, "Loss of thermionic emission in oxide-coated cathode tubes due to mechanical shock," PROC. 1.R.E., vol. 40, pp. 587-590; May, 1952.
Emission from cathodes continues indefinitely, but formation of aresistive barrier between the cathode and the coating causes afeedback and an apparent drop in the emissivity. Life studies showed that the resistance builds up to saturation value of about 40 ohm-squarecentimeters. Detection of this resistance was achieved by measurement of the mutual conductance at two frequencies.
One author supported Eisenstein's chemical theory-- resistive film formed at the interface by the formation of compounds of barium and core impurities deliberately introduced--which he felt explained the growth of cathode resistance. He favored this theory as being more probable and containing fewer inconsistencies than Raudorf's mechanical theory--shrinking of coating away from the core, leaving contact between the coating and the core only at minute discrete spots.
Methods were suggested of compensating for cathode resistance in design of circuits from audio to high radio frequencies.
(28) C. C. Eaglesfield, "Valve cathode life," Wireless World, vol. 57, pp. 505-506; December, 1951.
Other investigations by the British Post Office support Eisenstein's theory.
Another cause of oxide-cathode deterioration is poisoning attacks by residual gases. A method was developed of making atriode or pentode measure its own residual gas pressure.
(29) "Oxide cathode life," Wireless World, vol. 58, p. 76; Feb., 1952.
Noise measurements at high and low frequencies showed that the effect of space charge on flicker noise exceeds that for shot noise. Results reported were that the flicker-noise reduction factor had a value less than the shot-noise reduction factor at all current levels.
(30) T. B. Tomlinson, "Space charge reduction of low frequency fluctuations in thermionic emitters," Jour. Appl. Phys., vol. 23, pp. 894-899; August, 1952.
Secondary Emission: Determinations were made of the the secondary-emission threshold energy for various

composite surfaces. Results indicated that secondaries originate from the filled band of acompound rather than from electron traps.
(31) H. Jacobs, J. Martin and F. Brand, "Secondary emission from composite surfaces," Phys. Rev., vol. 85, pp. 441-447; February, 1952.
Magnetrons
A number of papers, concerned with the theoretical aspects of magnetrons, considered such topics as spacecharge distribution, RF phase control, amplifiers, potentials and instabilities.
(32) G. Hok, "A statistical approach to the space-charge distribution in a cut-off magnetron," Jour. Appl. Phys., vol. 23, pp. 983-989; September, 1952.
(33) E. E. David, Jr., "RF phase control in pulsed magnetrons," PROC. I.R.E., vol. 40, pp. 669-685; June, 1952.
(34) F. Lildi, "Theory of the magnetron amplifier," Z. angew. Math. Phys., vol. 3, pp. 119-128; March 15,1952. (German)
(35) K. Fritz, "Potentials and electron paths in multisegment magnetrons," Arch. Elek. (Uebertragung), vol. 6, pp. 211-215; May, 1952.
(36) L. A. Harris, "Instabilities in the smooth-anode cylindrical
m19a5g2n.etron," Jour. Ape Phys., vol. 23, pp. 562-567; May.

Theoretical and experimental studies were made of resonant-injection systems for the frequency control of magnetrons.
(37) L. L. Koros, "Frequency control of modulated magnetrons by resonant injection system," RCA Rev., vol. 13, pp. 47-57: March, 1952.
(38) J. S. Donal, Jr. and K. K. N. Chang, "Analysis of the injection locking of magnetrons used in amplitude-modulated transmitters," RCA Rev., vol. 13, pp. 239-257; June, 1952.

A number of papers described the design of magnetrons operating at frequencies of 7,000 and 9,310 mc.
(39) H. K. Jenny, "7000-megacycle developmental magnetron for frequency modulation," RCA Rev., vol. 13, pp. 202-223; June, 1952.
(40) G. A. Espersen and B. Arfin, "A 3 cm beacon magnetron." Philips Tech. Rev., vol. 14, pp. 250-258; August -September, 1952. (Dutch)

A unique magnetron of the interdigital type, intended for use with various external circuits as alocal oscillator operating from 0 to 1,000 mc, delivered amaximum power output of 0.5 watt.
(41) D. A. Wilbur, P. H. Peters and H. W. A. Chalberg, "Tunable miniature magnetron," Electronics, vol. 25, pp. 104-109; January, 1952.

Various experimental studies were made on harmonics, secondary emission, mode interaction, inverted magnetrons, and conductance measurements.

(42) J. A. Klein, J. H. N. Loubser, A. H. Nethercot, Jr., and C. H.

Townes, "Magnetron harmonics at millimeter wavelengths,"

Rev. Sci. Instr., vol. 23, pp. 78-92; February, 1952.

(43) F. W. Gundlach and K. Schürken, "The influence of secondary

emission on oscillation behaviour in cylindrical magnetrons,"

Z. angew. Phys., vol. 3, pp. 416-424; November, 1951. (Ger-

man)

(44)

R.R.Moats, "Mode interactions vol. 11, pp. 39-41; July, 1952.

in

magnetrons,"

Tele-Tech,

(45) J. F. Hull, "Inverted magnetron," PROC. I.R.E., vol. 40, pp.

1038-1041; September, 1952.

(46) M. Nowogrodzki, "Conductance measurements on operating

magnetron oscillators," PROC. I.R.E., vol. 40, pp. 1239-1243;

October, 1952.

A review article appeared relative to the modulation of cw magnetrons.

1953

Radio Progress During 1952

455

(47) J. S. Donal, "Modulation of continuous-wave magnetrons," Advances in Electronics, vol. 4, Academic Press, New York, N. Y.; 1952.
Further experiments were reported on cw magnetrons having two and four segments.
(48) E. B. Callick, "Experimental study of low-power cw magnetrons having few segments," PROC. I.R.E., vol. 40, pp. 836843; July, 1952.
A new textbook on magnetrons covered the properties, design, operation, constructional technique, and method of measurements.
(49) R. Latham, A. H. King, and L. Rushforth, "The Magnetron," Chapman and Hall, London; 1952.
Definitions of magnetron terms were completed by the IRE Magnetron Task Group.
(50) "Standards on magnetrons; definitions of terms, 1952," PROC. I.R.E., vol. 40, pp. 562-563; May, 1952.
A review article traced the historical development of magnetron theory and practice. Some of the constructional details of various magnetrons were included.
(51) J. Verweel, "Magnetrons," Philips Tech. Rev., vol. 14, pp. 5064; February, 1952. (Dutch)

Theoretical work continued on the space-charge effects in reflex klystrons and included modification of electronic admittance by a bunching-effectiveness parameter.
(59) M. Chodorow and V. B. Westburg, "Space-charge effects in reflex klystrons," PROC. I.R.E., vol. 39, pp. 1548-1555; December, 1951.

Klystrons
With the dimensional limitations of negative-grid tubes operating to reduce the power obtainable in the uhf and higher regions, considerable work on klystron
development was reported. In the design of high-powered oscillators, it was found
that an adverse effect, which was caused by the deflection of the electrons in the high-frequency field of the input gap, could be reduced by giving the output gap a suitable shape. An L cathode simplified the structure as well as supplying high current densities.
(52) B. B. van Iperen, "Velocity-modulation valves for 100 to 1,000 watts continuous output," Philips Tech. Rev., vol. 13, pp. 209222; February, 1952.

Three methods of electron-beam focusing of cascadetype klystron amplifier tubes were reported.
(53) V. Learned and C. Veronda, "Recent developments in highpower klystron amplifiers," PROC. I.R.E., vol. 40, pp. 465469; April, 1952.
Design concepts, tube structure, and tube characteristics were presented for apulsed klystron amplifier covering the range 960-1,215 mc.
(54) C. Veronda, "New pulse klystron amplifier for the 960-1,215 megacycle region," Elec. Eng., vol. 71, pp. 686-689; August, 1952.
The application of klystrons in frequency-modulated radio links was described.
(55) J. Cohn, "Operating klystrons in f-m microwave links," Electronics, vol. 25, pp. 124-127; June, 1952.
(56) D. E. Lambert, "A coaxial-line velocity-modulated oscillator for use in frequency-modulated radio links," Proc. IEE (London), paper 1337, TV Convention, 1952.
(57) A. H. Beck and A. B. Cutting, "Reflex klystrons for centimetre links," Proc. IEE (London), paper 1343, TV Convention, 1952.
(58) A. F. Pearce and B. J. Mayo, "The design of areflex-klystron oscillator for frequency modulation at centimetre wavelengths," Proc. IEE (London), paper 1301, TV Convention, 1952.

Fig. 1--This 200-pound electronic giant, the "klystron" tube developed by Varian Associates to G-E specifications, supplies power for the world's most powerful television station, WHOMTV, Reading, Pa. The tube, which has a power rating of 15,000 watts, is here being adjusted in its carrying rack by G-E engineer.
A number of review articles of interest appeared tracing the historical development of the art of klystrons as well as the progress of the past year.
(60) J. Racker and L. Perenic, "Microwave klystron oscillators," Radio and TV News, vol. 47, pp. 54-56; April, 1952 and pp. 64-66; May, 1952.
(61) R. H. Varian, "Recent developments in klystrons," Electronics, vol. 25, pp. 112-115; April, 1952.
Pulsed klystrons found applications in the uhf region. Two papers describing tubes used for air navigation appeared.
(62) V. Learned, "Power amplifier klystron for air navigation," Electronics, vol. 25, pp. 156-166; May, 1952.
(63) V. Learned, "Ground transmitter klystron for air navigation," Ekaronies, vol. 25, p. 136; January, 1952.

456

PROCEEDINGS OF THE I.R.E.

April

Traveling-Wave Tubes
A number of papers considered the theoretical aspects of traveling-wave tubes. The effect of thermal-velocity spread on the gain and noise figure was computed and found to be in good agreement with the empirical data. A theory was developed for an internal-feedback oscillator that neglects space-charge effects.
(64) D. A. Watkins, "Traveling-wave-tube noise figure," PROC. I.R.E., vol. 40, pp. 65-70; January, 1952.
(65) P. Parzen, "Effect of thermal-velocity spread on the noise figure in traveling-wave tubes," Jour. App!. Phys., vol. 23, pp. 394-406; April, 1952.
(66) E. M. T. Jones, "Internal feedback traveling-wave-tube oscillator," PRoc. I.R.E., vol. 40, pp. 478-482; April, 1952.
(67) J. Labus, "Optimum amplification in the helix traveling-wave tube," Arch. Elek. (Uebertragung), vol. 6, pp. 1-5; January, 1952. (German)
Theoretical and experimental studies of the travelingwave tube included its applications as aphase modulator, frequency shifter, and phase shifter.
(68) \V. J. Bray, "Traveling-wave valve as a microwave phasemodulator and frequency-shifter," Proc. IEE (London), Part III, vol. 99, pp. 15-20; January, 1952.
(69) I. D. Olin, "Traveling-wave tube as a phase-shifter," Bib. of Tech. Reports, vol. 18, p. 95; October 17,1952. PB111036.

ducing convergent beams made possible the use of lower current densities and thus prolong life.
(79) J. E. Pidquendar, "Electron guns for traveling-wave valves (Types M8 and Mil)," Ann. Télécomm., vol. 7, pp. 172-180; April, 1952.
A developmental low-noise traveling-wave amplifier for small signals was built for the 3,000-megacycle band and gave 8.5 decibels noise factor and 15-decibels gain under wide-frequency-band operation. An essential factor in this tube was aspecial "three-region" low-noise gun controlling the electrical drift angle of the beam.
(80) R. W. Peter, "Low-noise traveling-wave amplifier," RCA Rev., vol. 13, pp. 334-368; September, 1952.
A low-noise low-voltage traveling-wave tube of improved mechanical design was described. The theory of noise reduction was given, along with operating characteristics.
(81) J. H. Bryant, T. J. Marchese, and H. W. Cole, "Some recent developments in traveling-wave tubes for communication purposes," Elec. Commun., vol. 29, pp. 229-233; September, 1952.
(82) A. G. Peifer, P. Parzan, and J. H. Bryant, "Low-noise traveling-wave tube," Elec. Commun., vol. 29, pp. 234-237; September, 1952.

The application of traveling-wave tubes in radio beam links was reported in France.
(70) "Two traveling-wave valves for radio beam links," Ann. Télécomm., vol. 7, pp. 150-204; April, 1952.
(71) G. Goudet, "Traveling-wave valves in radio beam links," Ann. Télécomm., vol. 7, pp. 152-154; April, 1952.
(72) M. Kuhner and P. Lapostolla, "Two traveling-wave valves for radio beam links: general results and technology," Ann. Télécomm., vol. 7, pp. 155-168; April, 1952.
(73) P. Clostre and R. Wallauschek, "Two traveling-wave valves for radio beam links: measurements and characteristics," Ann. Télécomm., vol. 7, pp. 169-172; April, 1952.
A number of papers were published relative to traveling-wave-tube measurements and impedance matching to coaxial lines and waveguides.
(74) P. Clostre and R. Wallauschek, "A generator for measurements at U.H.F.," Ann. Télécomm., vol. 7, pp. 196-204; April, 1952.
(75) P. Clostre and R. Wallauschek, "Impedance matching of traveling-wave valves (Types M8 and M11) to coaxial lines," Ann. Télécomm., vol. 7, pp. 181-190; April, 1952.
(76) P. Chavance and L. Moutte, "Impedance matching of a traveling-wave valve (Type M8) to a waveguide," Ann. Télécomm., vol. 7, pp. 191-195; April, 1952.
A unique traveling-wave tube without retarding line employed a density-modulated beam that traverses a path along which the direction of the electric field is alternately positive and negative by using acylindrical waveguide divided into short cylinders, all the evennumbered cylinders being connected at one terminal and all the odd-numbered cylinders being connected at the other terminal.
(77) H. Kleinwâchter, "Traveling-wave valve without retarding line," Ekktrotech Z., vol. 72, pp. 714-717; December 15,1951.
A tube combining the properties of a klystron and distributed amplifier was described.
(78) T. G. Mihran "The duplex traveling-wave klystron," PROC. I.R.E., vol. 40, pp. 308-315; March, 1952.
Some work on electron-gun structures indicated that magnetic screening was necessary to reduce the deleterious effect of the magnetic field. Electron guns pro-

Space-charge-wave theory was applied to the study of space-charge-wave propagation in acylindrical beam.
(83) P. Parzan, "Space-charge-wave propagation in a cylindrical electron beam of finite lateral extension," Elec. Commun., vol. 29, pp. 238-242; September, 1952.

A method of solving electron-beam problems was described that took into account the thermal-velocity spread by amethod based on Liouville's theorem.

(84)

D. A. Watkins, "Effect electron stream," Jour.

Aofppvle.loPchiytsy.,divsotlr.i2b3u,tipopn.

in amodulated 568-573; May,

1952.

A comprehensive treatment of the theory of velocitymodulation tubes was published.
(85) R. Warnecke and P. Guenard, "Les tubes a commande par modulation de vitesse (Velocity-modulation tubes)," GauthierVillars, Paris; 1951.

The performance of space-charge-wave amplifier tubes was analyzed by considering them to be composed of basic "regions" or "spaces." A generalized electronic theory for all regions was developed and the circuit problem of individual regions discussed. A combination of the electronic and circuit relations for each region leads to equations describing the behavior of that region.
(86) R. G. E. Hutter, "Space-charge-wave amplifier tubes, basic principles of operation," Sylv. Tech., vol. 5, pp. 94-99; October, 1952.

Resnairons

A resnatron amplifier using the reflex principle in the output resonator was described as providing greater bandwidth than theretofore possible with this type of tube.
(87) G. I. Sheppard, M. Garbuny, and J. R. Hansen, "Reflex resnatrons show promise for VHF-TV," Electronics, vol. 25, pp. 116-119; September, 1952.

Video Camera Tubes The most recently developed video camera tube, the

1953

Radio Progress During 1952

457

vidicon, opened up new orbits of television in the industrial fields and allowed simplified camera equipment. In Europe, considerable interest was shown in the rather complex image iconoscope type of pickup tube, for which anumber of refinements have been worked out. A new monoscope based on secondary emission as a function of the angle of incidence was developed.
(88) R. Barthelemy, "Television analyzer (camera)," Onde Elect., vol. 31, pp. 415-419; November, 1951.
(89) R. Theile, "Image iconoscope for improved TV film scanning," Tele-Tech, vol. 10, pp. 44-46, 114-115; November, 1951.
(90) R. Theile and F. H. Townsend, "Improvement in image iconoscopes by pulsed biasing of the storage surface," PROC. I.R.E., vol. 40, pp. 146-154; February, 1952.
(91) J. E. Cope, L. W. Germany, and R. Theile, "Improvements in design of image iconoscope type camera tubes," lour. Brit. I.R.E., vol. 12, pp. 139-149; March, 1952.
(92) B. H. Vine, R. B. Janes, and F. S. Veith, "Performance of the vidicon, asmall developmental television camera tube," RCA Rev., vol. 13, pp. 3-10; March, 1952.
(93) J. E. I. Cairns, "A small high-velocity scanning television pick-up tube," Proc. IEE (London), part IIIA, vol. 99, pp. 89-94; April-May, 1952.
(94) R. D. Nixon, "The monoscope," Proc. IEE (London), part IIIA, vol. 99, pp. 132-135; April-May, 1952.
(95) R. Theile and H. McGhee, "An investigation into the use of secondary-electron multipliers in image iconoscopes," Proc. IRE (London), part IIIA, vol. 99, pp. 159-165; April-May, 1952.
(96) P. Schagen, H. Bruining, and J. C. Francken, "The image iconoscope, a camera tube for television," Philips Tech. Rev., vol. 13, pp. 119-133; November, 1951 (also abstract in Jour. SMPTE, vol. 58, pp. 501-514; June, 1952).
(97) S. T. Smith, "A novel type of monoscope," PROC. I.R.E., vol. 40, pp. 666-668; June, 1952.

tube for recording high speed transients," PRoc. I.R.E., vol. 40, pp. 297-302; March, 1952 (103) L. S. Allard, "Design factors in television cathode-ray tubes,» Proc. IEE (London), paper 1238, TV Convention, proof issue 1952. (104) A. Y. Bentley, K. A. Hoagland, and H. W. Grossbohlin, "Selffocusing picture tube,» Electronics, vol. 25, pp. 107-109; June, 1952. (105) G. N. Patchett, "Line eliminator," Wireless World, vol. 58, pp. 219-221; June, 1952. (106) K. Schlesinger, "Internal electrostatic deflection yokes," Electronics, vol. 25, pp. 105-109; July, 1952. (107) C. S. Szegho, "Cathode-ray picture tube with low focusing voltage," PROC. I.R.E., vol. 40, pp. 937-939; August, 1952. (108) C. V. Bocciarelli, "Low-power deflection for wide-angle C-R tubes,» Electronics, vol. 25, pp. 109-111; September, 1952. (109) C. V. Fogelberg, E. W. Morse, S. L. Reiches, and D. P. Ingle, "Using C-R tubes with internal pole pieces," Electronics, vol. 25, pp. 102-105; October, 1952.
Color Television Tubes
Development of tri-color kinescopes was being carried on along the various lines proposed in previous years.
(110) W. H. Buchsbaum, "The RCA tri-color tube," Radio & TV
News, vol. 46, pp. 52-54, 120-125; November, 1951. (111) J. H. Battison, "Analysis of latest Lawrence color-TV tube,"
Tele-Tech, vol. 10, pp. 38-39, 115; November, 1951. (112) W. P. O'Brien, "New Lawrence tri-color tube shown," Elec-
tronics, vol. 24, pp. 146, 148; November, 1951. (113) "Lawrence Color Tube," Sci. Am., vol. 185, pp. 33-34; Novem-
ber, 1951. (114) D. G. Fink, "Phosphor-strip tri-color tubes," Electronics, vol.
24, pp. 89-91; December, 1951. (115) H. R. Lubcke, "Color television reproducers," Jour. Soc. Mot.
Pic. and Telev. Eng., pp. 22-27; January, 1952. (116) E. G. Ramberg, "Elimination of moiré effects in tri-color kine-
scopes," PROC. I.R.E., vol. 40, pp. 916-923; August, 1952. (117) "Eidophor projector for theatre TV," Tele-Tech, vol. 11, pp. 57,
112-113; August, 1952. (118) "What is eidophor?,» Radio & TV News, vol. 48, pp. 94, 96;
August, 1952. (119) Aaron Nadell, "The eidophor projector," Radio-Electronics,
vol. 13, pp. 34-36; October, 1952.

Storage Tubes

Fig. 2--Side view of portable television camera using Vidicon tube and abuilt-in microphone for the narrator's use. The camera performs in conjunction with a battery-operated back-pack TV transmitter having a range of one mile. This new equipment, designed by RCA, permits "on-the-spot" pick-ups of special events and remote viewing of industrial processes.
Cathode-Ray Tubes
The size of direct-view picture tubes was increased steadily up to a 27-inch rectangular tube. Both allglass and metal-glass envelopes were used. Associated with this trend was the development of wide-angle deflection. Work was continued on tube envelopes, deflection and focusing systems with aview of reducing the amount of critical materials and production costs.
(98) C. S. Szegho and R. G. Pohl; "TV picture tubes with iron envelopes." TV Eng., vol. 2, pp. 8-9, 26-27; November, 1951.
(99) R. B. Mackenzie, "The modulation characteristic of cathode-
ray tubes in television," Brit. Jour. Appt. Phys., vol. 3, pp.
54-58; February, 1952. (100) C. S. Szegho, "I..arge flat-face cathode-ray tubes for radar,"
Tele-Tech, vol. 10, pp. 52-53, 94; January, 1952. (101) W. H. Buchsbaum, "Electrostatic focus for picture tubes,"
Radio & TV News, vol. 47, pp. 62-63, 130; March, 1952. (102) S. T. Smith, R. V. Talbot, and C. H. Smith, Jr., "Cathode-ray

Storage tubes found numerous applications for scan conversions and for computer memory systems. In addition to new developments, a comprehensive study of the basic principles was published.
(120) B. Kazan and M. Knoll, "Fundamental processes in charge controlled storage tubes,» RCA Rev., vol. 12, pp. 702-753; December, 1951.
(121) V. K. Zworykin and E. G. Ramberg, "Standards conversion of television signals," Electronics, vol. 25, pp. 86-91; January, 1952.
(122) W. E. Mutter, "Improved cathode-ray tube for application in Williams memory system," Elec. Eng., vol. 71, pp. 352-356; April, 1952.
(123) F. C. Williams, T. Kilburn, C. N. W. Litting, D. B. G. Edwards, and G. R. Hoffman, "Recent advances in cathode-ray tube storage," Proc. IRE (London), paper 1359, TV Convention, proof issue, 1952.
(124) M. Knoll and B. Kazan, "Storage Tubes and Their Basic Principles," John Wiley and Sons, Inc., New York, N. Y., Chapman & Hall Ltd., London; 1952.

Electron Optics

The quest for simple electron-lens designs led to
an attack from various directions: theoretical analyses,
development of devices for study of electron trajectories, and new lens configurations.

(125) L. Marton, M. M. Morgan, D. C. Schubert, J. R. Shah, and

J. A. Simpson, "Electron-optical bench," Jour. Res. Nat. Bur.

Stand., vol. 47, pp. 461-464; December, 1951.

(126)

JB.ritC..-fBouurrfoAoptp,i."PNhuymse.r,ivcoall.

ray-tracing 3, pp. 22-24;

in electron lenses," January, 1952.

458

PROCEEDINGS OF THE 1.R.E.

April

(127) P. Grivet et M. Bernard, "Théorie de la lentille électrostatique constituée par deux cylindres coaxiaux," Ann. Radioekc., vol. 7, pp. 3-9; January, 1952.
(128) M. G. Piétri, "Les tubes àfaisceau électronique laminaire, leur principle et quelques-unes de leurs applications," Vide, vol. 7, pp. 1113-1122; January, 1952.
(129) G. H. Vineyard, "Simulation of trajectories of charged particles in magnetic fields," Jour. Appl. Phys., vol. 23, pp. 35-39; January, 1952.
(130) P. Schagen, H. Bruining and J. C. Francken, "A simple electrostatic electron-optical system with only one voltage," Philips Res. Rep., vol. 7, pp. 119-130; April, 1952.
(131) M. Schtekel, "Electron optical velocity filters," Optik, vol. 9, pp. 145-153; April, 1952.
(132) C. T. Allison and F. G. Blackler, "A univoltage electrostatic lens for television cathode-ray tubes," Proc. IEE (London), paper 1333, TV convention, 1952.
(133) J. A. Hutton, "The focusing of cathode-ray tubes for television receivers," Jour. Brit. I.R.E., vol. 12, pp. 295-304; May, 1952.
(134) K. Jekelius, "Principles of permanent-magnet focusing systems for cathode-ray tubes," Fernmeldetech. Z., vol. 5, pp. 320326; July, 1952.
(135) K. F. Sander, C. W. Oatley, and J. G. Yates, "Factors affecting the design of an automatic electron-trajectory tracer," Proc. IEE (London), part III, vol. 99, pp. 169-179; July, 1952.
(136) H. Poritsky and R. P. Jerrard, "An integrable case of electron motion in electric and magnetic field," Jour. Appl. Phys., vol. 23, pp. 928-930; August, 1952.
(137) D. W. Shipley, "Calculation of spherical aberration for the electrostatic electron lens," Sylv. Tech., vol. 5, pp. 87-93; October, 1952.
Phototubes
Great interest developed in multiplier phototubes. Their use in scintillation counters became the predominant means for particle counting. Photoconductivity in various semiconductors was studied.
(138) L. Dunkelman and C. Lock, "Ultraviolet spectral sensitivity characteristics of photomultipliers having quartz and glass envelopes," Jour. Opt. Soc. Amer., vol. 41, pp. 802-804; November, 1951.
(139) J. A. Jenkins and R. A. Chippendale, "The application of image converters to high speed photography," Jour. Brit. I.R.E., vol. 11, pp. 505-517; November, 1951.
(140) B. T. Kolomiets, "Industrial types of photo-resistors," Electrichestvo, vol. 11, pp. 44-51; November, 1951.
(141) L. Reiffel, C. A. Stone and A. R. Brauner, "Fatigue effects in scintillation counters," Nucleonics, vol. 9, pp. 13-15; December, 1951.
(142) R. H. Warring, "Light sensitive cells; differentiation between photoelectric types," Elec. Rev. (London), vol. 149, pp. 11981200; December 14,1951.
(143) T. N. K. Godfrey, "Satellite pulses from photomultipliers," Phys. Rev., vol. 84, pp. 1248-1249; December 15,1951.
(144) V. Schwetzoff, S. Robin, and B. Vodar, "Electron-multiplier photocell for the ultraviolet down to 1450 A, Compt. Rend. Acad. Sci. (Paris) vol. 243, pp. 426-428; January 21,1952.
(145) W. C. Dunlap, Jr., "Germanium photocells," Gen. Elec. Rev., vol. 55, pp. 27-31; March, 1952.
(146) A. F. Gibson, "Single contact lead telluride photocells," Proc. Phys. Soc. (London), vol. 65B, pp. 196-214; March, 1952.
(147) A. F. Gibson, "Lead sulphide rectifier photocells," Prot. Phys. Soc. (London), vol. 65B, pp. 214-216; March, 1952.
(148) J. I. Pantchechnikoff, "Large area germanium photocell," Rev. Sci. Instr., vol. 23, p. 135; March, 1952.
(149) R. W. Engstrom, R. G. Stoudenheimer, and A. M. Glover, "Production testing of multiplier phototubes," Nucleonics, vol. 10, pp. 58-62; April, 1952.
(150) P. H. Keck, "Photoconductivity in vacuum coated selenium films," Jour. Opt. Soc. Amer., vol. 42, pp. 221-225; April, 1952.
(151) E. A. Taft and M. H. Hebb, "Note on quenching of photoconductivity in cadmium sulfide," Jour. Opt. Soc. Amer., vol. 42, pp. 249-251; April, 1952.
(152) Edward P. Clancy, "Polarization effects in photomultiplier tubes," Jour. Opt. Svc. Amer., vol. 42, p. 352; May, 1952.
(153) J. F. Raffle and E. J. Robbins, "Non-linear amplification in EMI photomultipliers," Proc. Phys. Soc. (London), B, vol. 65, pp. 320-324; May, 1952.
(154) R. K. Swank and W. L. Buck, "Observations on pulse-height resolution and photosensitivity," Nucleonics, vol. 10, pp. 5153; May, 1952.
(155) R. F. Post, "Performance of pulsed photomultipliers," Nucleonics, vol. 10, pp. 46-50; May, 1952.
(156) R. Wilson, "The fundamental limit of sensitivity of photometers," Rev. Sci. Instr., vol. 23, pp. 217-223; May, 1952.

(157) C. J. Milner and B. N. Watts, "Lead sulphide photo-cells," Research (London), vol. 5, pp. 267-273; June, 1952.
(158) D. W. Mueller, G. Best, J. Jackson, and J. Singletary, "Afterpulsing in photomultipliers," Nucleonics, vol. 10, pp. 53-55; June, 1952.
(159) E. S. Rittner and F. Grace, "Impedance measurements on PbS photoconductive cells," Phys. Rev., vol. 86, pp. 955-958; June, 1952.
(160) E. H. Gilmore and R. H. Knipe, "A method for spectral calibration of photomultipliers at low intensity levels," Jour. Opt. Soc. Amer., vol. 43, pp. 481-483; July, 1952.
(161) J. A. Jenkins and R. A. Chippendale, "Some new image converter tubes and their applications," Electronic Eng., vol. 24, pp. 302-307; July, 1952.
(162) E. F. Kingsbury and R. S. Ohl, "Photoelectric properties of ionically bombarded silicon," Bell Sys. Tech. Jour., vol. 31, pp. 802-815; July, 1952.
(163) J. I. Pantchechnikoff, S. Lasof, J. Kurshan, and A. R. Moore, "Use of flying spot scanner to study photosensitive surfaces," Rev. Sci. Instr., vol. 23, pp. 465-467; September, 1952.
(164) G. A. Morton, "The scintillation counter," Advances in Electronics, vol. IV, Academic Press Inc., New York, N. Y., pp. 69-107; 1952.
Gas Tubes
The cathode spot of mercury-pool cathodes was studied. Previous work was reviewed and an analysis was made of pool-surface and spot temperatures and of the current density in the cathode spot. It is concluded that the highest temperature found for the cathode spot is much too low for thermionic emission and that no relation can exist between the spot temperature and the mechanism of electron emission. Current densities of the order of 104 to 107 a/cm2,much higher than the generally accepted value of about 4,000 a/cm2 for cathode spots, have recently been measured. The difference appears to be due only to the difference in time, after spot initiation, at which the current density was measured. There is acontinuous decrease of current density and an increase in spot area with life of the spot.
(165) H. v. Bertele, "Pool surface and cathode spot temperature of mercury cathodes as aproblem in heat conduction," Brit. Jour. Appl. Phys., vol. 3, pp. 127-132; April, 1952.
(166) H. v. Bertele, "Current densities of free-moving cathode spots
on mercury," Brit. Jour. Appt. Phys., vol. 3, pp. 358-360; No-
vember, 1952.
Techniques of gaseous breakdown processes were explored and the results indicate their complexity. Three cathode and two anode mechanisms were analyzed and compared. Proper modern methods of discharge analysis were indicated.
(167) L. B. Loeb, "Secondary processes active in the electrical breakdown of gases," Brit. Jour. Appl. Phys., vol. 3, pp. 341-349; November, 1952.
New measurements of the drift velocity of electrons in argon as afunction of electric field, gas pressure, and impurity content (principally nitrogen) of the gas were made.
(168) L. Colli and U. Facchini, "Drift velocity of electrons in argon," Rev. Sci. Instr., vol. 23, p. 39; January, 1952.
A description of high-frequency gas-discharge breakdown is given describing the similarities and differences between these discharges and the more familiar dc type. High-frequency discharge breakdown is controlled by the process of electron diffusion and besides the theory of its behavior, the physical limitations of tube size, gas pressure, and frequency for this type of breakdown

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are given. The particular case of hydrogen is cited. The effects of superimposing aweak steady electric field and amagnetic field on the ac field are also described.
(169) S. C. Brown, "High-frequency gas-discharge breakdown," PROC. I.R.E., vol. 39, p. 1493; December, 1951.
A new cold-cathode high-voltage rectifier was described. Both theory and extensive experimental data were included. The operation of the tube is based on an improved type of electron trapping similar to that occurring in acylindrical magnetron in acutoff condition, but augmented due to the use of end plates on the cathode. Mercury vapor was used. This tube appears to offer for the first time apractical cold-cathode rectifier for voltages up to 14 kv and currents up to 1ma.
(170) E. G. Linde, J. H. Coleman, and E. G. Apgar, "A high-voltage cold-cathode rectifier," PROC. I.R.E., vol. 40, pp. 818-827; July, 1952.
Factors involved in the use of thyratrons at increased values of peak current and for short-time pulse switching continued to receive attention. The initial conduction interval was shown to depend on tube construction and on circuit elements.
(171) J. B. Woodford, Jr. and E. M. Williams, "The initial conduction interval in high speed thyratrons," Jour. Appl. Phys., vol. 23, pp. 722-724; July, 1952.
The uplasmatron," a new type of continuously controllable gas tube, was described and its operation analyzed. This tube utilizes an independently generated gas discharge plasma as aconductor between ahot cathode and an anode. Continuous modulation of the anode current can be effected by varying either the conductivity or effective cross section of the plasma.
Applications were reported to include motor drive, direct loudspeaker drive, high-efficiency rectification and inversion, and many others that require low-impedance operation.
(172) E. O. Johnson and W. M. Webster, "The plastmatron, acontinuously controllable gas-discharge developmental tube," PROC. I.R.E., vol. 40, pp. 645-659; June, 1952.
The special characteristics of some of the new miniature high-stability glow-discharge voltage-regulator tubes were studied in detail.
(173) F. A. Benson, "The characteristics of some miniature highstability glow-discharge voltage-regulator tubes," Jour. Sci. Instr., vol. 28, pp. 239-341; November, 1951.
(174) H. Bache and F. A. Benson, "A note on the temperature coefficients of running voltage of glow discharge tubes," Jour. Sci. Instr., vol. 29, pp. 25-26; January, 1952.
(175) H. Bache and F. A. Benson, "Peak-noise characteristics of glow-discharge voltage-regulator tubes," Electronic Eng., vol. 24, pp. 278-279; June, 1952.
(176) H. Bache and F. A. Benson, "Mean-noise characteristics of glow-discharge voltage-regulator tubes," Electronic Eng., vol. 24, pp. 328-329; July, 1952.
Major design features of new types of cold-cathode glow-discharge tubes were outlined and their useful applications in diverse kinds of circuits were indicated.
(177) G. H. Hough and D. S. Ridler, "Some recently developed cold cathode glow discharge tubes and associated circuits," Electronic Eng., vol. 24; Part 1, pp. 152-157; April, 1952; Part 2, pp. 230-235; May, 1952; Part 3, pp. 272-276; June, 1952.
New types of gas-filled cold-cathode counting tubes were described. The first one differs from early dekatrons in requiring only asingle input pulse to move the cathode glow acomplete step. Tentative specifications

were given for adevelopmental tube to operate at pulse rates up to 20,000 per second.
(178) J. R. Acton, "The single-pulse delcatron," Electronic Eng., vol. 24, pp. 48-51; February, 1952.
Another type of multicathode decade counter was described.
(179) G. H. Hough, "The development of a multi-cathode decade gas tube counter," Prot. IEE (London), Part III, vol. 99, pp. 166-167; May, 1952.
The design of a ten-stage counting tube designated 6167 was described. This tube operates up to about two thousand pulses per second and has the features which permit performing this pulse counting function with a minimum of circuit components and with ahigh degree of reliability. Such atube can be used for pulse counting, frequency divisions, time measurements, and similar functions. The mechanism of discharge transfer used in this design is reviewed and the details of construction and operating characteristics, and factors affecting life are described.
(180) D. S. Peck, "Ten stage cold cathode stepping tube," Elec. Eng., vol. 71, pp. 1136-1139; December, 1952.
Advances in the analysis of rectifier operation were reported.
(181) R. E. Turkington, "Analysis of the 3-phase inverter with resistive load," Elec. Eng., vol. 70, p. 1076; December, 1951.
(182) L. D. Harris, "Servo characteristics of a rectifier driven motor," Elec. Eng., vol. 71, p. 76; January, 1952.
(183) C. R. Reiter and C. R. Ammerman, "Dc motor losses with rectifier operation," Elec. Eng., vol. 71, p. 1025; November, 1952.
The two new ignitron -rectifier electric freight locomotives of 6,000 hp recently placed in service were described. The ability of a rectifier locomotive to operate at commercial frequencies higher than 25 cycles, necessitated by the limitations of ac motor design, offers the possibility of reducing electrification costs and widening the field of application.
(184) C. C. Whitaker and W. M. Hutchinson, "Pennsylvania Railroad ignitron rectifier locomotive," Elec. Eng., vol. 71, pp. 432437; May, 1952.
A simplified analysis of loss mechanisms in gas discharges was presented.
(185) S. C. Brown, "Physics of some loss mechanisms in gas discharges," Elec. Eng., vol. 71, pp. 501-503; June, 1952.
A novel portable radiation detector of phosphorphototube type was described. It was reported as being stable, having avery fast time constant, can be zeroed and calibrated in aradiation field, operates from common flashlight cells, and covers the range from approximately 0.05 to 500 roentgens per hour in four linear decades.
(186) Cole, Duffy, Hayes, Lusby, and Webb, "The phosphor-phototube radiation detector," Elec. Eng., vol. 71, pp. 935-939; October, 1952.
The anode-glow mode in which all ionization and excitation occur in a sheath close to the anode has been found to occur at low current values and at pressures in excess of 300 microns. The plasma potential approximates cathode potential and the tube drop occurs primarily in the anode sheath. Analysis shows that in this mode the anode current varies as the fourth power of

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April

the voltage excess above ionization potential. Axial and radial plasma density distributions have been determined.
(187) W. M. Webster, E. O. Johnson, and L. Malter, "Studies of externally heated hot cathode arcs part II--the anode-glow mode," RCA Rev., vol. 13, P. 163; June, 1952.
ye,

0 &IL

I is.

2 t«.

Fig. 3-(Lto R)--Two-point contact transistors, junction transistor,
and photo transistor. Paper clip and rule show comparative sizes. (Bell Telephone Laboratories).
Semiconductor Devices
The fourth year since the announcement of the transistor saw development progress greatly intensified in all areas of semiconductor technology. Perhaps in no other field in recent years has effort been so accelerated, with the result that so much has been learned about the physics of semiconductor material and devices with consequent improvement, modification, and development that now the manufacture and application of transistors has assumed a prominent position in any discussion of semiconductor work.
General: Some of the broader aspects of the application of transistors, as well as simplified discussion of the mechanism of conduction in germanium, were published.
(188) J. W. McRae, "Transistors in our civilian economy," Paoc. I.R.E., vol. 40, pp. 1285-1286; November, 1952.
(189) I. R. Obenchain, Jr. and W. J. Galloway, "Transistors and the Military," PROC. I.R.E., vol. 40, pp. 1287-1288; November, 1952.
(190) J. P. Jordan, "The ABC's of germanium,» Elec. Eng., vol. 71, pp. 619-625; July, 1952.
Semiconductor Material: The properties of singlecrystal germanium allowed the prediction of characteristics of junctions. The evaluation of fundamental properties of silicon was continued; measurements on single-crystal p-type silicon gave an electron mobility to 1,200 cm2/volt-sec, and avalue of 250 for holes in n-type silicon. P-n junctions were made by varying the rate of growth of acrystal from a melt containing two opposite-type impurities whose segregation constants vary:at different rates with growth velocity. Vacuum preparation of single-crystal germanium was performed.

A new method of alloying and diffusing indium into germanium to form p-n junctions was developed. Lifetime studies of injected carriers in germanium continued. The photoelectric and rectification properties of silicon bombarded by various ions were studied.
(191) G. K. Teal, M. Sparks, and E. Beuhler, "Single crystal germanium," Paoc. I.R.E., vol. 40, pp. 906-908; August, 1952.
(192) J. R. Haynes and W. C. Westphal, "The drift mobilities of electrons in silicon," Phys. Rev., vol. 85, p. 680; February 15, 1952.
(193) R. N. Hall, "P-n junctions produced by growth rate variation," Phys. Rev., vol. 88, p. 139; October 1, 1952.
(194) E. M. Conwell, "Properties of silicon and germanium," Paoc. I.R.E., vol. 40, pp. 1327-1337; November, 1952.
(195) L. Roth and W. E. Taylor, "Preparation of germanium single crystals," PROC. I.R.E., vol. 40, pp. 1338-1341; November, 1952.
(196) L. D. Armstrong, "P-n junctions by impurity introduction through an intermediate metal layer," PROC. I.R.E., vol. 40, pp. 1431-1342; November, 1952.
(197) D. Navon, R. Bray, and H. Y. Fan, "Lifetime of injected carriers in germanium," Paoc. I.R.E., vol. 40, pp. 1342-1347; November, 1952.
(198) L. B. Valdes, "Measurement of minority carrier lifetime in germanium," PROC. I.R.E., vol. 40, pp. 1420-1423; November, 1952.
(199) R. S. Ohl, "Properties of ionic bombarded silicon," Bell Sys. Tech. Jour., vol. 31, pp. 104-122; January, 1952.
Semiconductor Device Theory: Theory of alpha, the current-multiplication factor, and of noise in junction transistors and of current multiplication in point-contact transistors was studied. A nonmathematical discussion including the energy-band structure in semiconductors was used to explain rectification and transistor phenomena. A colloidal suspension of semiconductor materials in an electric field has a nonlinear resistance characteristic which is claimed to have surprisingly good frequency characteristics up into the microwave region. The formation of transistor collector was explained in terms of the more rapid diffusion of lattice vacancies than donor impurities, which should cause a p-n hook in n-type transistors but not in ptype. The location of ap-n junction with aprobe was used as the basis for determining the diffusion constants in germanium for arsenic, antimony, indium, and zinc. The diffusion constants obtained for arsenic into germanium using acapacitance method were found to be
several orders of magnitude smaller than those obtained by probing for the location of a p-n junction. A theory of contact noise was proposed based on temperature fluctuations in the neighborhood of the contact. It was found that noise in single crystals of germanium resides in the behavior of minority carriers and is quantitatively related to lifetime and transit time of these carriers.
(200) W. R. Sittner, "Current multiplication in the type-A transistor,» Paoc. I.R.E., vol. 40, pp. 448-453; April, 1952.
(201) E. Billig, "The physics of transistors," Brit. Jour. Appl. Phys., vol. 3, pp. 241-248; August, 1952.
(202) H. E. Hollman, "Dielectric and semiconductive suspensions,» Tele-Tech, vol. 11, pp. 56-59; September, 1952.
(203) R. L. Longini, "Electric forming of n-germanium transistor using donor-alloy contacts,» Phys. Rev., vol. 84, p. 1254; December 15, 1951.
(204) C. S. Fuller, "Diffusion of donor and acceptor elements into germanium," Phys. Rev., vol. 86, pp. 136-137; April 1, 1952.
(205) K. B. McAfee, W. Shockley, and M. Sparks, "Measurements of diffusion in semiconductors by a capacitance method," Phys. Rev., vol. 86, pp. 137-138; April I, 1952.
(206) R. L. Petritz, "A theory of contact noise," Phys. Rev., vol. 87, pp. 535-536; August 1, 1952.
(207) H. C. Montgomery, "Electrical noise in semiconductors," Bell Sys. Tech. Jour., vol. 31, pp. 950-976; September, 1952.

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Further theoretical work included treating as imperfections in anearly perfect crystal the concepts of holes, electrons, etc. A new class of unipolar transistors was discussed, including the analog transistor. Two new
elements in the theoretical small-signal equivalent circuit resulted from a study of how junction-transistor base thickness decreased as collector voltage increases. A comprehensive treatment of the Hall effect and the elimination of the effect of associated phenomena was presented. A theoretical analysis of the variation of base resistance with electrode spacing in point-contact transistors was checked fairly well by experiment. Postula-
tion of traps in the germanium player near the point
electrode was used to explain several recovery-time effects in germanium point-contact diodes. Matrix methods for transistor circuit analysis were used for theoretical work.
(208) W. Shockley, "Transistor electronics: imperfections, unipolar and analog transistors," PROC. I.R.E., vol. 40, pp. 1289-1313; November, 1952.
(209) J. M. Early, "Effects of space-charge layer widening in junction transistors," Pxoc. I.R.E., vol. 40, pp. 1401-1406; November, 1952.
(210) 0. Lindberg, "Hall effect," Pxoc. I.R.E., vol. 40, pp. 14141419; November, 1952.
(211) E. L. Steele, "Theory of alpha for p-n-p diffused junction transistors," PROC. I.R.E., vol. 40, pp. 1424-1428; November, 1952.
(212) L. B. Valdes, "Effect of electrode spacing on the equivalent base resistance of point-contact transistors," PROC. I.R.E., vol. 40, pp. 1429-1434; November, 1952.
(213) R. L. Petritz, "On the theory of noise in p-n junctions and related devices," PROC. I.R.E., vol. 40, pp. 1440-1456; November, 1952.
(214) M. C. Waltz, "On some transients in the pulse response of point-contact germanium diodes," PROC. I.R.E., vol. 40, pp. 1483-1487; November, 1952.
(215) J. Shekel, "Matrix representation of transistor circuits," PROC. I.R.E., vol. 40, pp. 1493-1497; November, 1952.

(218) J. A. Morton, "Present status of transistor development," PROC. I.R.E., vol. 40, pp. 1314-1326; November, 1952. Also Bell Sys. Tech. Jour., vol. 31, pp. 411-443; May, 1952.
(219) W. C. Dunlap, Jr., "Germanium photocells," Gen. Elec. Rev., vol. 55, pp. 26-31; March, 1952.
(220) "The junction transistor," Electronics, vol. 24, pp. 82-85; November, 1951.
(221) F. J. Lingel, "Germanium power rectifier construction," Electronics, vol. 25, p. 210; June, 1952.
(222) M. J. E. Golay, "The equivalent circuit of the transistor," PROC. I.R.E., vol. 40, p. 360; March, 1952.
(223) L. B. Valdes, "Transistor forming effects in n-type germanium," PROC. I.R.E., vol. 40, pp. 445-447; April, 1952.
(224) B. N. Slade, "A method of improving the electrical and mechanical stability of point-contact transistors," RCA Rev., vol. 12, pp. 651-659; December, 1951.
(225) E. S. Rittner and F. Grace, "Impedance measurements on PbS photoconductive cells," Phys. Rev., vol. 86, pp. 955-958; June 15,1952.
(226) E. Billig, "Effect of minority carriers on the breakdown of point-contact rectifiers," Phys. Rev., vol. 87, pp. 1060-1061; September 15,1952.
(227) J. A. Morton, "New transistors give improved performance," Electronics, vol. 25, pp. 100-103; August, 1952.
(228) B. J. Rothlein, "A photovoltaic germanium cell," Sylv. Tech., pp. 86-88; October, 1951.
(229) E. F. Kingsbury and R. S. Ohl, "Photoelectric properties of ionically bombarded silicon," Bell Sys. Tech. Jour., vol. 31, pp. 802-816; July 1952.
Silicon p-n junction diodes have been constructed with rectification ratios as high as 10 8 at 1volt, ability to operate at ambient temperatures up to 300°C, and other improved characteristics. Further work was done on fused-contact p-n-p germanium transistors. The
equivalent circuit of the four-terminal p-n-p-n trans-
istor was derived, and the current gain analyzed when the transistor is connected as a hook-collector transistor. This work included a method of adjusting gain ·by external means. The theory was developed for anew form of transistor of the field-effect type in which the conductivity of a layer of semiconductor is modulated

Semiconductor Devices: Construction and characteris- by a transverse electric field. A device, the fieldistor, tics of junction diodes, transistors, and photocells were with input impedance of about 10 megohms, low output

reviewed. A simplified equivalent circuit of the impedance, and ag,,, of 1,000 micromhos was developed grounded-emitter-transistor amplifier was presented. Ex- whose control electrode was separated by afew microns

perimental evidence was reported that supports the p-n from the p-n junction. Operating frequency of conven-

hook mechanism in point-contact transistors. The use tional junction transistors was increased by 10 times or of thermosetting resins for embedding point-contact more on experimental models by adding a fourth elec-

transistors resulted in amarked improvement in trans- trode to the base and biasing it so that the base re-

istor mechanical and electrical stability.

sistance is decreased by asubstantial factor. A new pho-

Analysis of impedance versus frequency on lead- toelectric device was proposed that would permit modu-

sulfide photoconductive cells offered an explanation in lation of alight beam by the change in absorption due

terms of distributed capacitance, which was not by to injected carriers. A p-n junction photocell was de-

itself evidence for or against abarrier picture. The cause veloped with asensitivity of 30 ma per lumen correspondof electric breakdown in point-contact diodes was sug- ing to aquantum yield of approximately unity, and with

gested to be intrinsic conduction due to thermal gen- afrequency response flat into the 100-kc region.

eration and subsequent passage of minority carriers. Characteristics and operation of point-contact and junction transistors were compared with respect to linear and large-signal characteristics, reliability, life, temperature effects, and electrical performance. Measurements on developmental germanium photovoltaic cells were carried out. Photocells were made from ionically bombarded silicon with properties dependent on the energy of bombarding particles and silicon temperature.
(216) J. S. Saby, "Germanium transistors," Gen. Elec. Rev., vol. 55, pp. 21-24; September, 1052.
(217) T. J. Ferguson, "The G-10 germanium rectifier," Gen. Elec. Rev., vol. 55, pp. 29-31; July, 1952.

(230) G. L. Pearson and B. Sawyer, "Silicon p-n junction diodes," PROC. I.R.E., vol. 40, pp. 1348-1951; November, 1952.
(231) R. R. Law, C. W. Mueller, J. I. Pankove (Pantchechnikoff), and L. 15. Armstrong, "A developmental germanium p-n-p junction transistor," Pxoc. I.R.E., vol. 40, pp. 1352-1357;
·November, 1952. (232) J. S. Saby, "Fused impurity p-n-p junction transistor," PROC.
I.R.E., vol. 40, pp. 1358-1360; November, 1952. (233) J. J. Ebers, "Four terminal p-n-p-n transistors," PROC. I.R.E.,
vol. 40, pp. 1361-1364; November, 1952. (234) W. Shockley, 'A unipolar field effect' transistor," PROC.
I.R.E., vol. 40, pp. 1365-1376; November, 1952. (235) 0. M. Stuetzer, "Junction fieldistors," PROC. I.R.E., vol. 40,
pp. 1377-1381; November, 1952. (236) R. L. Wallace, Jr., L. G. Schimpf, and E. Dickten, "A junction
transistor tetrode for high-frequency use," Pxoc. I.R.E., vol. 40, pp. 1395-1400; November, 1952.

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April

(237) K. Lehovec, "New photoelectric devices utilize carrier injection," PROC. I.R.E., vol. 40, pp. 1407-1409; November, 1952.
(238) J. N. Shive, "Properties of m-1740 p-n junction photocell," PROC. I.R.E., vol. 40, pp. 1410-1413; November, 1952.
Transistor Circuits: Application and circuit develop-
ment progressed rapidly with work on transistor amplifiers, oscillators, modulators, and multivibrators. Substitution of transistors for vacuum tubes in afrequencyshift converter for radio-teletype equipment was re-
ported. Maximizing power gain and efficiency of junction transistors in class-A and -B audio amplifiers was analyzed.
A transistor audio oscillator with varistor stabilization was developed for operation over a range of temperatures and supply voltages. Transistor amplifier instability due to variation in emitter and collector bias
currents was analyzed. Transistor noise was investigated theoretically and experimentally for both junction and point-contact types; noise was found to vary with collector voltage and emitter current with the former and to be relatively independent of those factors with the latter type. Several theorems on noise spectra and noise correlation were derived; the noise figure of transistors
can then be calculated for any desired external circuit from equivalent noise generators of simple but arbitrary configuration that have their noise spectra given. Studies of temperature variation of transistor parameters on two point-contact types showed that gain is
reduced by only 2 db up to approximately 60°C and units at this temperature are satisfactory for many small-signal applications. The control possibilities of transistors were discussed with reference to fairly large units performing functions now handled by magnetic amplifiers, amplidynes, and thyratrons. Numerous other circuit applications were developed including transistor binary counters, high-voltage low-current power supplies, printed circuits applied to transistors, transistors in airborne equipment, transistor trigger and switching circuits and theory, and various phases of digitalcomputer circuits.

Test Methods: Transistor and semiconductor test methods also received considerable attention. Oscilloscopic displays of families of transistor characteristics were developed, some of which permitted easy evaluation of alpha and other parameters. Dynamic test methods were developed to facilitate extensive germanium-diode-testing programs; these included visual I--E characteristics, recovery tests, and temperature
and humidity characteristic tests. Test procedures were described which check selenium cells for forward and reverse characteristics over arange of temperatures.
(251) M. L. Wood, "Transistor characteristic curve plotter," IBM Corp. Report, No. 06,071.402; August 19,1952.
(252) N. Golden and R. Nielson, "Oscilloscopic display of transistor static electrical characteristics," PROC. I.R.E., vol. 40, pp. 1437-1439; November, 1952.
(253) D. J. Crawford and H. F. Heath, Jr., "Germanium diode testing program," IBM Corp. Report; March 6,1952.
(254) C. A. Kotterman, "Production testing of selenium cells," Electronics, vol. 25, pp. 272-284; March, 1952.

(239) G. Raisbeck, "Transistor circuit design," Electronics, vol. 24, pp. 128-134; December, 1951.
(240) G. S. Epstein, J. A. Bush, and B. Shellhorn, "Transistorizing communication equipment," Electronics, vol. 25, pp. 98-102; May, 1952.
(241) R. F. Shea, "Transistor power amplifiers," Electronics, vol. 25, pp. 106-108; September, 1952.
(242) D. E. Thomas, "Low-drain transistor audio oscillator," PROC. I.R.E., vol. 40, pp. 1385-1395; November, 1952.
(243) R. F. Shea, "Transistor operation: stabilization of operating points," PROC. I.R.E., vol. 40, pp. 1435-1437; November, 1952.
(244) E. Keonjian and J. S. Schaffner, "An experimental investigation of transistor noise," PROC. I.R.E., vol. 40, pp. 1456-1460; November, 1952.
(245) H. C. Montgomery, "Transistor noise in circuit application," PROC. I.R.E., vol. 40, pp. 1461-1471; November, 1952.
(246) A. Coblenz and H. L. Owens, "Variation of transistor parameters with temperature," PROC. I.R.E., vol. 40, pp. 1472-1476; November, 1952.
(247) E. F. W. Alexanderson, "Control applications of the transistor," PROC. I.R.E., vol. 40, pp. 1508-1511; November, 1952.
(248) G. W. Bryan, "Application of transistors to high-voltage lowcurrent supplies," PROC. I.R.E., vol. 40, pp. 1521-1523; November, 1952.
(249) S. F. Danko and R. A. Gerhold, "Printed circuitry for transis-
'tors," PROC. I.R.E., vol. 40, pp. 1524-1528; November, 1952. (250) 0. M. Stuetzer, "Transistors in airborne equipment," PROC.
I.R.E., vol. 40, pp. 1529-1530; November, 1952.

Fig. 4--Audio amplifier stage with four-junction transistors, developed at the David Sarnoff Research Center of RCA at Princeton, New Jersey, provides sufficient amplification to operate a loudspeaker.
Audio Techniques
Several historical summaries were presented and are of particular interest because they include the background of the early telephone applications of audio techniques.
(255) M. J. Kelly, "Communication and electronics," Elec. Eng., vol. 71, pp. 965-969; November, 1952.
(256) A. B. Clark, "The development of telephony in the United States," Commun. and Electronics, AIEE, no. 3, pp. 348-364; November, 1952.
Mutual understanding between audio art and science was furthered by abook. Several reviews and summaries of principles appeared.

1953

Radio Progress During 1952

463

(257) H. F. Olson, "Musical Engineering," McGraw-Hill Book Co., New York, N. Y.; 1952.
(258) N. H. Crowhurst, "The prediction of audio frequency response," Electronic Eng. (London), vol. 23, pp. 440-443, November, 1951; pp. 483-489, December, 1951; vol. 24, pp. 33-38, January, 1952; pp. 72-86, February, 1952.
(259) J. G. Miles, "Types of magnetic amplifiers--Survey," Commun. and Electronics, AIEE, no. 1, pp. 229-238; July, 1952.
(260) E. M. Villchur, "Handbook of sound reproduction," Audio Eng., vol. 36, pp. 18-20; June 1952; pp. 15-18, 40, July, 1952; pp. 20-21, 54-55, August, 1952; pp. 38-40, 51-54, September, 1952; pp. 36-37, 88-91, October, 1952; pp. 40-44, 74-75 November, 1952; pp. 20-22, 39-45, December, 1952.

Much greater use of multiple recording at differing speeds was made, producing novel effects such as artificial extension of instrumental range beyond the actual
acoustic range.
In reproductionifromidisks, substantial general improvement in compliance and tracking of pickups was accomplished, together with better damping and transient response. Use of diamond styli in reproduction was
substantially increased, in both professional and non-

Reports of specific audio-system applications and equipment refinements included the industrial application of loudspeakers and the avoidance of "splatter."
(261) S. C. Bartlett, "Loudspeaker systems in power plants," Elec. Eng., vol. 70, pp. 1057-1062; December, 1951.
(262) J. L. Reinartz, "Increased audio without splatter," TRANS. I.R.E., PGA-9, pp. 22-28, September-October, 1952.
(263) A. Peterson and D. B. Sinclair, "A single-ended push-pull audio amplifier," PROC. I.R.E., vol. 40, pp. 7-11; January, 1952.
(264) A. L. Hammond, "Neutralizing hum and regeneration,"Audio Eng., vol. 36, pp. 22, 53-56; May, 1952.
(265) V. Brociner and G. Shirley, "The OTL (output-transformerless) amplifier," Audio Eng., vol. 36, pp. 21-23, 45-46; June, 1952.

professional applications. Considerable improvement in signal-to-noise ratio in commercially available preamplifiers for disk reproduction in custom installations was noted, together with increased range and flexibility of frequency response control, and reduction of transient and other distortions was apparent.
Further investigation of applications of mechanical principles to sound recording problems was made.
(268) J. F. Doust, "The application of elementary mechanics to sound recording," Sound Recording and Reproduction, vol. 3, pp. 198-201; December 1951.
In the field of magnetic recording on tape, further in-

There were two reports on the perennial intermodulation distortion measurement.
(266) P. J. Aubry, "Intermodulation testing," Audio Eng., vol. 35, pp. 22-23, 41-42; December, 1951.
(267) R. C. Hitchcock, "Intermodulation distortion," Audio Eng., vol. 36, pp. 21-22, 56; October, 1952.
Sound Recording and Reproduction

vestigation of the mechanism of the magnetic recording
process was conducted, and considerable information on the inherent characteristics of tape was developed. Improved dynamic range and average signal-to-noise ratio was achieved in tapes providing a greater maximum signal amplitude capability for agiven percentage distortion. Tape with 1.5 and 2.0 mil Milar bases became

Progress in disk recording was confined principally to refinements of existing techniques and devices. Increased playing time without reduction of maximum peak amplitude of the modulated groove was achieved by extensive use of variable groove spacing, controlled either manually or automatically. Automatic adjust-

available, giving greater freedom from humidity and varying tension effects. Timing difficulties due to large ratios of maximum-to-minimum tape tension in machines with constant torque take-up were reduced
through adoption of tape reels with larger hub diameter than older types.

ment of groove spacing to accommodate peak-to-peak (269) P. E. Axon, "Mechanism of magnetic recording," Wireless

program amplitude was accomplished by means of a

World, pp. 47-50; February, 1952.

control signal taken from a special level-monitoring

A new method of recording on magnetic tape anal-

magnetic pickup head over which the master program ogous to variable-area optical sound-on-film recording

tape passes before reaching the pickup feeding the re- was reported. A new type of three-pole magnetic re-

cording cutter amplifier. The control signal was used cording head was described in which the normal gap

to regulate the speed of the motor driving the cutter field was nonsymmetrically distorted, resulting in in-

feed screw in such away as to increase the groove spac- creased resolution and an improved optimum bias ad-

ing above a set minimum at any given time propor- justment. Further studies of wear of magnetic recording

tional to the peak-to-peak amplitude of the program and playback heads were made in an effort to establish

signal at that time. Playing time up to 65 minutes on the general characteristics of normal wear in use. Fur-

a single 12-inch disk at 33.3 rpm became possible by ther work was done in development of mixed ferrites

use of this technique. Improved quality of cut was ac- for use in magnetic recording heads and in grinding and

complished by extensive use of heated stylus cutters, polishing tape-bearing faces of ferrite heads.

and reduction of cutter head bounce. A trend among

Certain standards for disk and magnetic tape record-

record producers to standardize on a500-cycle turnover ing were recommended for adoption internationally.

frequency became noticeable, but no general agreement There was apparent agreement among various recom-

on the shape of the response curve below turnover ap- mendations on disk speeds and response curves. Con-

peared.

siderable agreement on tape speeds was also evident,

Processes for duplicating disk recordings were im- but lack of agreement on response curves for tape media

proved by adoption of electrolytic cleaning and polish- still existed. The problem of print-through in magnetic

ing for masters and stampers, and a wider use of all- tape was also given further study. There was some indi-

nickel stampers. Some 45-rpm disks were duplicated by cation that the print-through effect was increased by

injection molding in polystyrene.

oxide carried over the tape edge in the slitting operation.

464

PROCEEDINGS OF THE I.R.E.

April

(270) H. L. Daniels, "Boundary-displacement magnetic recording," Electronics, vol. 25, pp. 116-120; April, 1952.
(271) M. Camras, "New magnetic recording head," Jour. Soc. Mot. Pic. and Telev. Eng., vol. 58, pp. 61-66.
(272) British Standards Institution, CO (ACM) 4731-2-3.
Binaural recording and reproduction on both disk and tape media was introduced, and binaural broadcasting over paralleled AM and FM transmitters was presented experimentally.
(273) B. Cook, "Recording binaural sound on disk," Tele-Tcch, vol. 11, pp. 48-50,136-140; November, 1952.
(274) 0. Bixler, "A commercial binaural recorder," Jour. Soc. Mot. Pic. and Telev. Eng., vol. 59, pp. 109,117; August, 1952.

Electroacoustics
Loudspeakers
An interesting development was the ionic loudspeaker. Klein utilized an alternating ionic discharge in ahorn formed of quartz to obtain afaithful reproduction of sound without amoving membrane. Meager data were given on efficiency; apparently the output was found to be adequate for practical purposes. The chief drawback seems to be the use of expensive quartz, which is necessary because of the high temperatures and

In usage of magnetic recording, there was wide- voltages involved.

spread adoption of the medium for all steps in the pro-

For the first time, a simple method was developed

duction of sound motion-picture film. Such usage pro- for measuring the amplitude and phase at various points

vides immediate playback and lowered costs in most on a vibrating loudspeaker cone. The cone is covered

intermediate editing operations. Two systems of mag- with alight coat of conducting paint, and acapacitive

netic recording for this purpose are in use. One system probe is brought near the point to be measured. The

employs a magnetic coating on sprocketed film, the varying capacitance is measured during movement to

second uses standard 1-inch magnetic tape with asyn- give the amplitude and phase.

chronizing signal recorded with the program material

An outstanding paper on the use of loudspeakers in

taking the place of the sprocket holes to provide syn- speech reinforcment was that of Beranek and his co-

chronization with the picture film. For editing and processing operations up to the final
release negative, use of a magnetic strip on sprocketed film became almost universal practice. Such usage was in three forms: as a full-width track on sprocketed

workers. It outlined methods for using speech-reinforce-
ment systems in large auditoriums. The principal suggestion was that there be less use of reinforcement at low frequencies, in order to prevent masking of the higher frequencies by low-frequency reverberation.

35-mm stock; as astrip of lesser width (magnestrip) on clear stock, or stock for positive optical printing of a parallel duplicate track for editing convenience; and on clear stock with avisible editing track put on mechan-
ically with aball-point pen head for similar reasons. In the use of 1-inch tape for recording sound track,
there was general informal agreement on the use of 14 kc as a carrier frequency in synchronizing control

(275) -S. Klein, "The ionic loudspeaker," TSF pour Tous, vol. 27, pp. 278-281; September, 1951; "The physical principles of the ionic loudspeaker and microphone,» TSF pour Tous, vol. 27, pp. 340-342; October, 1951.
(276) M. S. Corrington and M. C. Kidel, "Amplitude and phase measurements on loudspeaker cones," PROC. I.R.E., vol. 39, pp. 1021-1034; September, 1951.
(277) L. L. Beranek, W. H. Radford, J. A. Kessley, and J. B. Wiesner, "Speech-reinforcement system evaluation," Pitoc. I.R.E., vol. 39, pp. 1401-1408; November, 1951.

tracks with 60-cycle modulation and an average carrier Sound Absorption and Room Acoustics

level 20 to 30 db below the average program level in the medium. Exception to the trend toward use of 60-cycle
modulated 14-kc carrier remained in the continued use
of a60-cycle control signal recorded in the tape medium at an angle of 90 degrees to the program recording.
Devices to start and stop magnetic tape in synchronism with motion picture film in projectors (automatic framing devices) began to find acceptance in
major networks and film companies. Devices were also developed for applying visible numbers and frame lines
to 1-inch magnetic recording tape to correspond with footage and frame indications on standard 35-mm mo-
tion-picture film. This permitted direct editing of such tape without need for aparallel optical track for footage
and frame referencing. A demonstration of recording and reproduction of
sight and sound on magnetic tape was made using a
speed of 100 inches per second with results improved over those of last year but still marred by ghosts and snow. The tape used was 1 inch wide and bore 12 parallel magnetic tracks, ten carrying picture information, the remaining two carrying sync signals and
sound.

Progress was made in understanding the fundamental properties of acoustic materials and in relating these properties to the random sound fields that occur in enclosed spaces. Inard and Bolt reported on a method of measuring the acoustic impedance of an absorbing surface to waves of oblique incidence. The impedance was found for materials for which it is in-
correct to assume a constant normal impedance. The method consists of measuring, with aprobe microphone, the change in amplitude and phase of the pressure on a flat area when it is changed from ahard surface to one covered with the, acoustic material under test.
Lawhead and Rudnick applied the Sommerfeld theory of propagation of radio waves over an absorbing surface to the case of acoustic propagation. They were able to measure the complex propagation constants of acoustic materials.
The modern acoustic design of the legislative chambers of the National Capitol was described by P. E. Sabine.
(278) U. Ingird and R. H. Bolt, "Free field method of measuring the absorption coefficient of acoustic materials," Jour. Acous. Soc. Amer., vol. 23, pp. 509-517; September, 1951.

1953

Radio Progress During 1952

465

(279) R. B. Lawhead and I. Rudnick, "Measurements on an acoustic wave propagated along a boundary," Jour. Acous. Soc. Amer., vol. 23, pp. 541-546; "Acoustic wave propagation along aconstant normal impedance boundary," Jour. Acous. Soc. Amer., vol. 23, pp. 546-550; September, 1951.
(280) P. E. Sabine, "Acoustics of the remodeled House and Senate Chambers of the National Capitol," Jour. Acous. Soc. Amer., vol. 24, pp. 121-125; January, 1952.
Noise and Hearing
Noise reduction and prevention of hearing loss due to excessive noise levels received much attention. A considerably better understanding of the hearing mech-

(289) W. Kallenbach, "Further investigation of pitch recorders for application to phonetic research," Akus. Beihefle, vol. 1, pp. 37-42; 1951.
(290) B. H. Edgarth, "The sound film spectrograph," IVA (Stockholm), vol. 22, no. 5, pp. 134-153; 1951.
(291) K. Tamm and I. Putsching, "A frequency analyzer with a mechanical high frequency filter," Akus. Beihefte, vol. 1, pp. 43-48; 1951.
(292) C. J. LeBel and James Y. Dunbar, "Ultra speed recording for acoustical measurements," Jour. Acous. Soc. Amer., vol. 23, pp. 559-563; September, 1951.
(293) M. Harrison, A. O. Sykes, and P. G. Marcotte, "Reciprocity calibration of piezoelectric accelerometers," Jour. Acous. Soc. Amer., vol. 24, pp. 384-390; July, 1952.

anism has evolved in the past five years. Fletcher developed a mathematical theory for the mechanics of the inner ear based on Békésy's experimental data, and this now explains most of the dynamics of the hearing mechanism.
Much data on the hearing mechanism are now being obtained in terms of bands of noise instead of pure-tone data. Pollack published equal-loudness contours for broad-band noise and otuer data on the aural response to broad-band excitation. Mintz and Tyzzer published a loudness chart by which the loudness of broad-band noise measured in octave bands can be quickly converted into asingle loudness figure.
· (281) H. Fletcher, "On the dynamics of the cochlea," Jour. Acous. Soc. Amer., vol. 23, pp. 637-646; November, 1951.
(282) H. Fletcher, "Dynamics of the middle ear and its relation to the acuity of hearing," Jour. Acous. Soc. Amer., vol. 24, pp. 129-131; March, 1952.
(283) I. Pollack, "On the threshold and loudness of repeated bursts of noise," Jour. Acous. Soc. Amer., vol. 23, pp. 646-650; November, 1951.
(284) I. Pollack, "Sensitivity to differences in intensity between repeated bursts of noise," Jour. Acous. Soc. Amer., vol. 23, pp. 650-654; November, 1951.
(285) I. Pollack, "On the measurement of the loudness of white noise," Jour. Acous. Soc. Amer., vol. 23, pp. 654-658; November, 1951.
(286) I. Pollack, "Comfortable listening levels for pure tones in quiet and noise," Jour. Acous. Soc. Amer., vol. 24, pp. 158-163; March, 1952.
(287) I. Pollack, /our. Acous. Soc. Amer., vol. 24, pp. 533-538; September, 1952.
(288) F. Mintz and F. G. Tyzzer, "Loudness chart for octave-band data on complex sounds," Jour. Acous. Soc. Amer., vol. 24, pp. 80-82; January, 1952.
Sound Instrumentation and Measurement

Theory of Transducers

Hunt pointed out that correlation methods, which are making important contributions to such diverse fields as communication, information theory, and aerodynamic turbulence, can be used to enhance the space resolution of directional receivers. Since noise can be expected to come from all directions and the signal from only one, aspace correlation of the direction of arrival of energy can give much information.
Bauer gave avaluable analysis of acoustic diaphragms by considering them in analog form as a series of ideal transformers, each of which corresponds to aparticular area of the diaphragm.
Stevenson published anumber of equations for wave propagation in horns.

(294) F. V. Hunt, "Perturbation and correlation methods for en-

hancing the space resolution of directional receivers," PROC.

I.R.E., vol. 39, p. 840; July, 1951.

(295) B. B. Bauer, "Transformer analogs of diaphragms," Jour. Acous. Soc. Amer., vol. 23, pp. 680-683; November, 1951.

(296)

Ap.roFp.agSatteivoennsinona,co"uEstxiaccthoarnnsd,"apJporuor.xiAmpapt!e.

equation for wave Phys., vol. 22, pp.

1461-1463; December, 1951.

Ultrasonics
The field of ultrasonics has continued to be very active, especially in Europe. A book on this subject has been written by Vigoureux. Several scientists discovered new methods of detecting an ultrasonic field, such as the use of astarch plate in adilute solution of iodine, temperature-sensitive chromatic components, leucobases

In Europe, there was considerable activity in the of dyes, thermostimulable phosphors, temperature-

development of sound spectrographs or "visible- sensitive phosphors, and various types of Schlieren

speech" apparatus. Edgarth developed a spectrograph equipment.

using sound film. Tamm and Putsching developed a The use of ultrasonic equipment in pathological treat-

precise narrow-band filter using mechanical elements. ments has developed to agreater extent in Europe than

This filter uses coupled steel resonators, giving a 15- in the United States. However, the mechanism that

cycle bandwidth. It is capable of resolving two com- causes acoustic energy to be absorbed in tissue appears

ponents 25 cycles apart that differ in level by 40 db. to have been solved by an American scientist, W. J.

The dynamic range is 65 db.

Fry.

In the United States, LeBel and Dunbar announced

Another application of ultrasonics has been the study

a high-speed level recorder operating electronically, of details in aerodynamic fields. By this method much

which uses improvements on Hunt's early methods to more information can be obtained without disturbing

obtain writing speeds up to 10,000 db per second.

the field than by hot-wire techniques.

Several laboratories applied to accelerometers and

Also of interest to the electronic industry was the

vibration pickups the reciprocity techniques of calibra- announcement of a nondestructive method for testing

tion formerly used for microphones (underwater and in ceramic insulators by the use of ultrasonics.

air). Harrison, Sykes, and Marcotte extended this technique to 10,000 cps.

(297) P. Vigoureux, "Ultrasonics," John Wiley and Sons, Inc., New York, N. Y.; 1951.

466

PROCEEDINGS OF THE

April

(298) P. J. Ernst and C. W. Hoffman, "New methods of ultrasonoscopy and ultrasonography," Jour. Acous. Soc. Amer., vol. 24, pp. 207-211; March, 1952.
(299) G. S. Bennett, "New method for the visualization and measurement of ultrasonic fields," Jour. Acous. Soc. Amer., vol. 24, pp. 470-474; July, 1952.
(300) R. Hanel, "Making ultrasonic waves visible," Radio Tech. (Vienna), vol. 27, pp. 325-329; August, 1951.
(301) W. J. Fry, "Mechanism of acoustic absorption in tissue," Jour. Acous. Soc. Amer., vol. 24, pp. 412-415; July, 1952.
(302) M. Merle, "Use of ultrasonic waves for the study of an aerodynamic field," Acustica, vol. 1,263, pp. 104-108; 1951.
(303) H. Barthelt and A. Lutsch, "Nondestructive testing of ceramic insulators by ultrasound," Siemens Zeit., vol. 26, pp. 114-121; April, 1952.
Video Techniques

under operating conditions is described in a report on this subject. By means of amultiplier phototube and a line-selector type of blanking circuit, oscillograms are obtained showing the vertical distribution of light intensity for single lines and for adjacent lines.
(314) J. Green, "Evaluating performance of TV picture tubes," Electronics, vol. 25, pp. 124-129; February, 1952.
Theoretical and experimental evaluation of the signalto-noise ratio in flying-spot scanners and adiscussion of the influencing factors were given in another report.
(315) A. J. Baracket, "Signal-to-noise ratio in television flying spot scanner," Tele-Tech, vol. 10, pp. 42-44; December, 1951.

A tutorial paper described the basic method of specifying the performance of photographic materials and discussed some of the variables which affect film performance and the relations of these variables to video recording. Video recording on film has been the subject of considerable theoretical and experimental attack. Work on video recording has not been restricted to film. Advances were made in the experimental recording of video information on tape.

The measurement of amplitude linearity in a television system often requires the disabling of line to lineclamping circuits. A description was given of amethod of measurement using familiar laboratory equipment, such as a square-wave generator and oscilloscope together with agray-scale generator, for making the test with the clamping operative.
(316) G. E. Hamilton and R. Ilowite, "Gray scale generator," Electronics, vol. 25, pp. 143-145; November, 1952.

(304) G. H. Gordon, "Video recording, film considerations," PROC. I.R.E., vol. 40, pp. 779-782; July, 1952.
(305) P. J. Herbst, R. O. Drew, and J. M. Brumbaugh, "Factors affecting the quality of kinerecording," SMPTE Jour., vol. 58, pp. 85-104; February, 1952.
(306) R. I. Kuehin, "Improved photo-recording from cathode-ray TV tubes," Tele-Tech, vol. 11, pp. 48-49; February, 1952.
(307) P. Mandel, "An experimental system for slightly delayed projection of television pictures," PROC. I.R.E., vol. 40, pp. 11771184; October, 1952.

An examination of the possibilities of using information theory in an attempt to reduce bandwidth requirements was made.
(317) C. W. Harrison, "Experiments with linear prediction in television," Bell Sys. Tech. Jour., vol. 31, no. 4, pp. 764-783; July, 1952.
(318) E. R. Kretzmer, "Statistics of television signals," Bell Sys. Tech. Jour., vol. 31, no. 4, pp. 751-763; July, 1952.

Fundamental investigations of gradation and resolution were reported.
(308) 0. H. Schade, "Image gradation, graininess and sharpness in television and motion picture systems," SMP TE Jour., vol. 58, pt. II, pp. 181-222; March, 1952.
(309) L. C. Jesty and N. R. Phelp, "The evaluation of picture quality with special reference to television systems," Marconi Rev., pt. I, vol. 15, pp. 113-116; 3rd quarter, 1951; pt. II, vol. 15, pp. 156-186; 4th quarter, 1951.
Picture quality and ways and means of improving it have been the subject of concerted attacks by workers in the field. One report described arelatively rapid method of measuring resolution and localizing the sections of a television system that degrade it. This measurement utilized aspecial signal generator giving apicture containing awhite rectangle on ablack background.
(310) R. K. Seigle, "Television streaking test set," Electronics, vol. 24, pp. 96-99; November, 1951.
(311) G. G. Gouriet, "A method of measuring TV picture detail," Elec. Eng., vol. 24, No. 293, pp. 308-311; July, 1952.
Some of the factors affecting interlacing were discussed in another paper.
(312) G. N. Patchett, "Faulty interlacing," Wireless World, vol. 58, pp. 250-254,315-319; July and August, 1952.
The effective cross talk in the video channel introduced from asecond circuit was examined under conditions where the effective intercoupling network had four different loss-frequency characteristics.
(313) A. D. Fowler, "Observer reaction to video crosstalk," SMPTE Jour., vol. 57, pp. 416-424; November, 1951.
One of the elements in apicture monitor, the characteristics of which contribute to resolution, is the picture tube. The accurate measurement of spot dimensions

The interconnection of stations transmitting under different standards is possible, using either the intermediate-film method or storage-type tubes. The problems that remain in the latter method have been considerably reduced by recent work.
(319) V. K. Zworykin and E. G. Ramberg, "Standards conversion of TV signals," Electronics, vol. 25, pp. 86-91; January, 1952.
A more complete description was given of a continuous motion-picture projector utilizing a system of mirrors rotating in synchronism with the film to produce an effective optical lap dissolve from one frame to another. A servomechanism is used to minimize intensity flicker.
(320) A. G. Jensen, R. E. Graham, and C. F. Mattke, "Continuous motion picture projector for use in television film scanning," SMPTE Jour., vol. 58, pp. 1-21; January, 1952.
Improvements in techniques and equipment were described for both the image orthicon and the image iconoscope type pickup tubes.
(321) A. Reisz, "A new all-purpose television camera," Tele-Tech, vol. 11, pp. 38-40; April, 1952.
(322) R. Theile and F. H. Townsend, "Improvements in image iconoscopes by pulsed biasing the storage surface," PROC. I.R.E., vol. 40, pp. 146-154; February, 1952.
Radio Transm itters
Television Broadcasting
Television broadcasting was initiated in Canada during 1952, astation being placed in operation in Toronto and one in Montreal.
(323) J. E. Hayes, "Television Facilities of the Canadian Broadcasting Corp," Presented at Soc. Mot. Pic. and Telev. Eng. Convention; October 6,1952.

1953

Radio Progress During 1952

467

New and improved facilities were also made available in the United States.
(324) J. R. Poppele, "The new WOR Studio and Transmitter Building, 60th Street and Columbus Avenue, N.Y.C.," Presented at I.R.E. National Convention, New York, N. Y.; March, 1952.
(325) J. G. Leitch, "New Building and Technical Facilities at WCAU, Philadelphia, Pa." Presented at I.R.E. National Convention, New York, N. Y.; March, 1952.
(326) C. L. Dodd, "The WFAA-TV plant, Dallas, Texas," Presented at I.R.E. National Convention, New York, N. Y.; March, 1952.
(327) R. D. Chipp, "Television control room layout." Tele-Tech, pp. 48-50; October, 1952.
Due mostly to the unfavorable economic situation, there was little activity abroad, except in France and England.
In the United States, television played an important part in providing coverage of the Democratic and Republican national presidential conventions.
(328) R. D. Chipp, "Pool Master Control," Presented at I.R.E. Professional Group on Broadcast Transmission Systems Conference, Philadelphia, Pa.; October 27, 1952.
The production of programs was enhanced due to the steady evolution of production techniques, and the improvement of equipment generally.
(329) C. R. Paulson, "TV Production Techniques," Presented at I.R.E. Professional Group on Broadcast Transmissilns Systems Conference, given at Second Annual Prof. Group Broadcast Symposium, Philadelphia, Pa.; October 27, 1952.
(330) L. L. Pourciau, "Television Camera Equipment of Advanced Design" Presented at Soc. Mot. Pic. and Telev. Eng. Convention; October, 1952.
(331) "Tele prompter," Join.. Soc. Mot. Pic. and Telev. Eng.; June, 1952.
(332) F. Fodor, "Filmcraft's Camera Control System," Presented at Soc. Mot. Pic. and Telev. Eng. Convention; October, 1952.
The development of flying spot scanners occupied the attention of many engineers and equipment manufacturers during 1952.
(333) G. R. Tingley, R. D. Thompson, and J. H. Haines, "A Universal Scanner for Color Television." Presented at I.R.E. National Convention, New York, N. Y.; March, 1952.
(334) J. W. Wentworth, "Flying-Spot-Scanner Gamma-Correction Circuits," Presented at I.R.E. Professional Group on Broadcast Transmission Systems Conference, Philadelphia, Pa.; October 27, 1952.
(335) R. H. Hammans, "Flying Spot Telecine Equipment and Its Use at BBC," Presented at Second Annual I.R.E. Prof. Group Broadcast Symposium; October 27, 1952.
(336) J. H. Haines, "Flying Spot Scanner Optics," Presented at I.R.E. Professional Group on Broadcast Transmission Systems Conference, Philadelphia, Pa.; October 27, 1952.
(337) R. E. Graham, "Flying Spot Scanner Design," Presented at I.R.E. Professional Group on Broadcast Transmission Systems Conference, Philadelphia, Pa.; October 27, 1952.
There was a considerable improvement in rear-ofscreen projection techniques for studio use, in the development of new projection equipment, as well as in the use of teletranscriptions or kinescope recordings.
(338) A. Jenkins, "Rear Screen Projection," Presented at IRE Professional Group on Broadcast Transmission Systems Conference, Philadelphia, Pa.: October 27, 1952.
(339) W. E. Stewart, "New Professional Television Projector," Presented at, Soc. Mot. Pic. and Telev. Eng. Convention; October, 1952.
(340) R. E. Lovell, "Time-zone Delay of Television Programs by Means of Kinescope Recording," Presented at Soc. Mot. Pic., and Telev. Eng. Convention; October, 1952.
The use of image orthicon cameras for the televising of motion picture film also came into use.
(341) R. D. Chipp, "Film Projection Using Image Orthicon Cameras," Presented at Soc. Mot. Pic. and Telev. Eng. Convention; October, 1952.

Considerable advances were made in tue "shooting" of live television shows on film.
(342) K. Freund, "Shooting Live Television Shows on Film," Presented at Soc. Mot. Pic. and Telev. Eng. Convention; October, 1952.
Broadcasters were occupied with station planning throughout the United States because of the lifting of the "freeze" on construction permits by the Federal Communication Commission, and many new stations were planned throughout the country for 1953.
UHF Television
The Federal Communications Commission on April 14, 1952 issued its "Sixth Report and Order Concerning the Television Broadcast Service," suspending the "freeze order" on construction of new stations in effect since September 30, 1948. The Commission's "Rules, Regulations, and Engineering Standards" were amended and an additional 70 channels, each 6 mc wide, in the 470-890 mc band were allocated for television stations.
(343) Federal Communications Commission, "Sixth Report and Order" F.C.C. 52-294; adopted April 11, 1952, and released April 14, 1952.
Of the more than 100 new station authorizations issued by the FCC since the lifting of the freeze, the majority were for stations in the uhf band but only a very few were in operation at the end of the year. With the demand for early completion of new uhf broadcasting stations and for home receivers the television industry activity in engineering development, product design, and manufacture of uhf equipment received great impetus.
The first commercial uhf station, KPTV, in Portland, Oregon was put in operation on Channel 27 with approximately 16-kw effective radiated power produced by a1-kw development model transmitter and high-gain slot antenna. Beam tilting of the main lobe of approximately 2° down from the horizontal was employed in the antenna system. Field testing of propagation and coverage as well as the performance of receivers in this new area has provided much valuable information.
(344) J. P. Taylor "UHF in Portland--how is it doing?," Broadcast News, special ed., pp. 2-23; October, 1952.
Progress in uhf transmitter development and design covered a broad front, with particular design effort being directed toward final product and manufacture in the shortest possible time. Initial designs were limited in power output to approximately 1, 5, and 10-12 kw, being based on the use of tetrodes or klystron tubes for the power output stage.
(345) V. Zeluff "Transmitters for uhf television," Electronics, vol. 25, pp. 102-104; July, 1952.
The types of tetrode tubes for approximately 1-kw output were of low-loss ceramic-to-metal seal construction and with anode fin radiators for air cooling. These types permitted the transmitter cavities to be designed for full coverage of the 470-890-mc frequency band with external tuning controls.
(346) Electronics, vol. 25, p. 244; June, 1952.

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Klystrons were of the three-cavity type and stagger tuned to obtain the required bandwidth for each 6-mc channel. The 5-kw klystron was designed for use with external cavities and the 12-15-kw klystron with cavities integral with the tube.
(347) R. H. Varian "Recent developments in klystrons," Electronics, vol. 25, pp. 112-115; April, 1952.
(348) "High power uhf klystron," Tele-Tech, vol. 11, pp. 60-61; October, 1952.
Development work on both tubes and circuits, looking toward improved methods for obtaining the desired uhf power most efficiently, continued and included systems based on triode, tetrode, klystron, resnatron, magnetron, and traveling-wave types of tubes. Development was started on aklystron tube capable of producing 75 kw over the 470-890 mc band.
(349) V. Learned and C. Varonda, "Recent developments in highpower klystron amplifiers," PROC. I.R.E. ,vol. 40, pp. 465-469; April, 1952.
(350) D. B. Harris, "New uhf resnatron designs and applications," Electronics, vol. 24, pp. 86-89; October, 1951.
(351) D. B. Priest, "Coaxial tetrode as a TV amplifier at vhf and uhr," Tele-Tech, vol. 11, pp. 52-53 and 80-88; January, 1952.
(352) P. T. Smith, "Some new ultra-high frequency power tubes,» RCA Rev., vol. XIII, pp. 224-238; June 1952.
(353) G. E. Sheppard, M. Garbuny, and J. R. Hansen, "Reflex resnatron shows promise for uhf TV,» Electronics, vol. 25, pp. 116-119; September, 1952.
(354) D. H. Priest, "Tetrodes improve harmonic generation at vhf and uhf," Tele-Tech, vol. 11, pp. 60-61, 118-120 and 123; April, 1952.
(355) "A 75 kw klystron tube for uhf TV," TV Digest, vol. 8, p. 5; November 1, 1952.
Much progress was made in high-gain antennas, transmission lines, sideband filters, and notch diplexers. One slot-type antenna has a power gain varying from 24 to 27 depending on the frequency. Methods of pattern testing and adjustment before erection were developed. New coaxial transmission lines were developed and made available. A 50-ohm 31-inch diameter line with teflon insulators, permits apower rating of 24 kw and a loss of 0.220-db feet at channel 14 and a14-kw power rating and loss of 0.406 db feet at channel 83. For high towers where long lengths of line are required and for higher powers, a 75-ohm 61-inch diameter line with teflon insulators was developed having a power rating of 100 kw and loss of 0.102 db feet at channel 14 and 50-kw power rating and loss of 0.210 db feet at channel 83. For still higher power ratings and still lower losses, copper-clad steel waveguides were developed. Further field measurements were made and work continues on the effects of expected in coverage by antenna-beam tilting and to verify the results obtained by increasing antenna heights under different terrain conditions. An important development for uhf antenna systems was an improved combination of vestigial sideband filter and constant-impedance notch diplexer, called a "filterplexer," having the necessary filter characteristics and feeding both sound and picture trans-
mitters into asingle transmission line.
(356) M. W. Scheldorf, "Broad band antenna element," Tele-Tech, vol. 11, pp. 50-51; January, 1952.
(357) 0. 0. Feit, "A new uhf television antenna TFU24B," Broadcasting News, pp. 8-23; March--April, 1952.
(358) E. H. Shively, "Pattern testing the TFU24137UHF antenna," Broadcasting News, pp. 42-51; May--June, 1952.

(359) 0. 0. Feit, "New 31" uhf ultra low loss coaxial line," Broadcasting News, pp. 30-35; September--October, 1951.
(360) J. Epstein, D. W. Peterson, and O. M. Woodward, Jr., "Some types of omnidirectional high gain antennas for use at ultrahigh frequencies," RCA Rev., vol. XIII, pp. 137-162; June, 1952.
(361) J. Epstein and D. W. Peterson, "Broadcasting TV in the uhf Band," Electronics, vol. 25, pp. 102-109; November, 1952.
(362) Federal Communication Commission, "Public Notice No. 74835"; April, 1952.
(363) R. I. Brown, "WABD's new television transmitter," TeleTech, vol. 11, pp. 53-55, 96; May, 1952.
(364) J. S. Donal, Jr. and K. K. N. Chang, "An analysis of the injection locking of magnetrons used in amplitude modulated transmitters," RCA Rev., vol. XIII, no. 2, pp. 239-257; June, 1952.
(365) R. G. Peters, "Ultra-high transmitter and antenna design and applications, » TV Eng., vol. 2, pp. 14-17, 29; October, 1951.
(366) P. Guenard, B. Epsztein, and P. Cahoun, "Klystron amplificateurs de 5kilowatts alarge bande passante," Ann. Radioelec., vol. 6, no. 24, pp. 109-113; April, 1951.
(367) W. H. Sayer, Jr., "UHF transmitter uses beer-barrel cavity," Electronics, vol. 24, pp. 125-127; December, 1951.
(368) Staff Written, "The Holme-Moss television transmitter," Elec. Eng. (London), vol. 23, pp. 434-435; November, 1951.
(369) D. B. Weigall, "Holme-Moss television transmitting station," BBC Quart., vol. 6, pp. 183-192; Autumn, 1951.
(370) Staff Written, "Kirk o'Shotts transmitting station," Jour. Telev. Soc., vol. 6, no. 9, p. 357; January--March, 1952.
(371) Staff Written, "Kirk o'Shotts television transmitting station," Engineer (London), vol. 193, pp. 371-373; March 14, 1952.
(372) W. Burkhardtmaier, "Development problems of the television transmitter," Telefunken Z. ,vol. 24, pp. 193-203; December, 1951.
(373) H. de Waard, "Television broadcasting in Holland," Jour. Telev. Soc., vol. 6, no. 8, p. 299; October-December, 1951.
(374) E. Demus, "Experimental television transmitter of the German Postal Administration on the Gr. Feldberg (Tannus)," Funk Technik (Berlin), vol. 7, no. 9, pp. 232-233; 1952.
(375) P. A. T. Bevan and others, "Symposium of papers on the Sutton Coldfield television station,» Prot. IEE (London), vol. 98, pt. 3, pp. 416-470; November, 1951.
Microwave Communication
The demand for new microwave installations for approved services and for extension of facilities to other services was of sufficient magnitude to require areview of the entire allocation plan under the sponsorship of the FCC. Considerable activity in this field was reported from abroad.
(376) JTAC Report, "Radio Spectrum Conservation,» McGrawHill Book Co., Inc., New York, N. Y.; 1952.
(377) D. N. Lapp and A. B. Hopple, "VHF-UHF turnpike radio systems," FN-TV, vol. 12, pp. 29-31, 34; June, 1952.
(378) Staff Written, "Microwave links Freeport mines," Chem. Eng., vol. 48, p. 41; June, 1952.
(379) C. M. Backer, "Microwave system design for utilities," TeleTech, vol. 10, pp. 48-50, 84; December, 1951.
(380) L. Christensen, "Twenty-four channel microwave telephone equipment of Danish manufacture," Teleteknik, vol. 2, pp. 161-167; July, 1951.
(381) J. B. L. Foot, "1400-MC/s radiophone," Wireless World, vol. 58, pp. 132-135; April, 1952.
(382) H. Keeling, "Gas pipeline radio system," FM-TV, vol. 12, pp. 17-21, 40; January, 1957.
(383) J. A. Craig, "Automatic radio repeater system," PRoc. I.R.E., vol. 39, pp. 1524-1529; December, 1951.
(384) C. F. Hobbs, "Close channel spacing at vhf and higher frequencies," PROC. I.R.E., vol. 40, pp. 329-334; March, 1952.
(385) J. Peters, "Carrier-frequency systems free from linear distortion," Arch. elekt. (Uebertragung, vol. 5, pp. 509-515; November, 1951.
(386) P. Marzin, "Radio links, general technical consideration," Ann. Telecommun., vol. 6, pp. 363-380; December, 1951.
(387) L. Persson, "Radio links for power stations," Ericsson Rev., no. 2, pp. 42-47; 1951.
(388) R. Siegert, "Transportable USW directional link equipment," Telefunken Z., vol. 24, pp. 204-212; December, 1951.
(389) K. O. Schmidt, "Planning radio links," Fernmeldleck. Z., vol. 43, pp. 531-536; December, 1951.
(390) M. J. Dockes, "Frequency generation for radio relay systems," Echo de'Recherches, no. 7, pp. 20-25; April, 1952.

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Common Carrier Radio Relay
The facilities for wide-band communication service were expanded rapidly. Many new cities received service for both television programs and multi-channel telephone traffic. In Europe, multiplexed communications for toll service received considerable attention with major emphasis on equipment of somewhat less traffic-handling capacity than the newer United States installations.
(391) J. G. Chaffee and J. B. Maggio, "Frequency-modulation terminal equipment for transcontinental relay system," Elec. Eng., vol. 70, pp. 880-883; October, 1951.
(392) B. R. Tupper and P. B. Patton, "Multiple-channel telephony on VHF radio links," PROC. I.R.E., vol. 40, pp. 913-916; August, 1952.
(393) R. W. Friis and K. D. Smith, "An unattended broad-band microwave repeater for the TD-2 radio relay system," Elec. Eng., vol. 70, pp. 976-981; November, 1951.
(394) P. Barkow, "Linearity limits of discriminators, particularly for wide-band FM radio beam links," Fernmeldteck. Z., vol. 5, pp. 179-186; March-April, 1952.
(395) F. Ring, "Transmission characteristics of the V -60 carrierfrequency equipment," Fernmeldteck. Z., vol. 5, pp. 101-108 and 179-186; February, 1952.
(396) K. O. Schmidt, "Some data on two former multichannel beam links from Athens to Rome and Crete," Telefunken Z., vol. 25, pp. 64-68; March, 1952.
(397) H. J. Fründt, "A 50 MC/S beam link with ±500 KC/S frequency swing," Telefunken Z., vol. 25, pp. 510-519; March, 1952.
(398) E. Kniel and K. H. Baer, "The radio common-wave system of the Südwestfunk," Tech. Hausmitt. Nordw. Dtsch. Rdfunks., vol. 4, pp. 47-51; March-April, 1952.
(399) L. C. Simpson, H. J. B. Nevitt, and E. J. Eriksen, "VHF radio multi-channel carrier telephone circuits in Colombia,» Ericsson Rev., vol. 28, pp. 62-72; 1951.
(400) K. O. Schmidt, "The planning of beam links in the decimeter and centimeter wave bands," Telefunken Z., vol. 24, pp. 129139; October, 1951.
(401) G. Ulbricht, "The IDA-2 beam-link equipment," Telefunken Z., vol. 24, pp. 143-162; October, 1951.
(402) Staff Written, "Radio telephone communication in the Chamonix Valley," Rev. des Posies, vol. 7, no. 9, pp. 18-23; March-April, 1952.
(403) R. Rivere and M. Schwindenammer, "The equipments of the Dijon-Strasbourg multi-channel radio link," Onde Elec., pp. 163-173; April-May, 1952.
(404) H. Gutton, J. Fagot, and J. Hugon, "The equipment of the Paris-Lille multi-channel radio link," Onde Elec., pp. 174-180; April-May, 1952.
Television Relaying
In addition to the relay facilities made available by the common carriers, considerable progress was reported on mobile equipment for use in remote programming. This field received considerable attention in foreign countries.
(405) A. H. Mumford, "Television radio relay links," Jour. Telev. Soc., vol. 6, pp. 290-299; October-December, 1951.
(406) J. H. Battison, "Microwaves: backbone of network televivision," Tele-Tech, vol. 11, pp. 62-63, 113; January, 1952.
(407) T. H. Bridgewater, "Paris-London television," Elec. Eng. (London), vol. XXIV, no. 295, pp. 410-412; September, 1952.
(408) Y. Angel and P. Riche, "The Paris-Lille television radio link," Onde Elec., pp. 152-157; April-May, 1952.
(409) J. Laplume, S. Schirman, R. Fraticelli, and R. Jeannin, "The Paris-Lille television radio link equipment," Onde Elec., pp. 158-162; April-May, 1952.
International Broadcasting and Communication
Further progress in the utilization of single-sideband transmission and multichannel operation was reported. Efforts were mainly directed toward better utilization of the spectrum.

(410) L. M. Klenk, A. J. Munn, and J. Nedelka, "A multi-channel single side-band radio transmitter," Pxoc. I.R.E., vol. 40, pp. 783-796; May, 1952.
(411) A. E. Kerwien, "Modulation equipment for modern singlesideband transmitters," PROC. I.R.E., vol. 40, pp. 797-803; July, 1952.
(412) L. R. Kahn, "Single-sideband transmission by envelope elimination and restoration," PROC. I.R.E., vol. 40 pp. 803-806; July, 1952.
(413) N. Lund, C. F. Rose, and L. G. Young, "Amplifiers for multichannel single-sideband radio transmitters," PROC. I.R.E., vol. 40, pp. 790-796; July, 1952.
(414) D. J. Ambercrombie, "Parasitic oscillation in radio transmitters," Proc. I.R.E. (Australia), vol. 12, pp. 206-209; July, 1951.
(415) M. Suppan, "The new Italcable radio transmitting station of Torrenova,"Poste eTelecommun., vol. 19, pp. 473-481; October, 1951.
(416) A. Gaillard, "Le Groupe H. F. D'Allouis--Issondun de la Radio-Diffusion Francoise," Onde Elec., 31st year, no. 296; November, 1951.
(417) Veaux, "Progress and Development of Long Distance Radio Links by the Administration of P.T.T.," Rev. des P.T.T., vol. 7, pp. 34-42; January-February, 1952.
(418) J. R. Heck, "4.5 KW in 2sq. ft.," FM-TV, vol. 12, pp. 30-31, 34; August, 1952.
(419) W. A. Krause, "Portable radio telephone equipment for communication between ship and shore," Frequenz, vol. 6, pp. 146-149; May-June, 1952.
A31 Broadcasting
Several new transmitters were described. The major activity was reported by workers outside of the United States with emphasis on remote control, automatic control, and unattended operation. Parallel operation of transmitters is being extended for the purpose of transmission continuity.
(420) M. H. Hutt, "AM transmitter design," Radio and Telev., vol. 47, pp. 3-5, 29; January, 1952.
(421) M. H. Hutt, "New 5 KW AM transmitter," Broadcast News, no. 66, pp. 48-55; September-October, 1951.
(422) M. H. Hutt, "Mechanical design of a 10 KW radio transmitter," Elec. Mfg., vol. 48, pp. 92-95, 266, 268; November, 1951.
(423) A. G. Robeer and B. Swets, "Description of a40 KW broadcast transmitter," Commun. News, vol. 12, pp. 16-32; October, 1951.
(424) A. Schweisthal, "Twin drive as active research for broadcast transmitters," Tech, Hausmitt. NordwDtsch. Rdfunks., vol. 4, pp. 42-45; March-April, 1952.
(425) A. Schweisthal and K. H. Baer, "The Ravensburg 2X20 KW broadcast transmitter," Tech. Hausmitt. NordwDtsch. Rdfunks., vol. 4; March-April, 1952.
(426) A. Kolarz and E. Kniel, "Problems of automatic operation of transmitting groups," Tech. Hausmitt. NordwDtsch. Rdfunks., vol. 4, pp. 59-62; March-April, 1952.
(427) Staff Written, "Broadcasting installations for the two programmes in Denmark," Tektenik, (Copenhagen) vol. 2, pp. 207-249; October, 1951.
(428) Staff Written, "Unattended high power radio transmitter," Engineer, vol. 193, p. 146; March 21, 1952.
(429) Staff Written, "Remote control of BBC high power transmitter," Elec. Eng. (London), vol. 24, p. 229; May, 1952.
(430) F. A. Peachy, R. Toombs, and C. Gunn-Russell, "BBC new automatic unattended technique," Eke. Eng. (London), vol. 24, pp. 446-449; October, 1952.
FM Broadcasting
Circuit developments in FM transmitters were reported. Very few new stations were erected in the United States. The greatest interest in this field has been in other countries.
(431) H. G. Stratman, "FM transmitter for 42 MCS," Radio and Telev., vol. 47, pp. 10-13, 31; June, 1952.
(432) J. Hacks, "Investigations of FM systems with negative feedback," Arch. ekkt. Ubertragung, vol. 5, pp. 441-446; October, 1951.
(433):W. Mansfeld, "Realizability of the point of inflection of a modulation characteristic for FM by means of reactance valves," Frequenz, vol. 5, pp. 317-333; November-December, 1951.

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(434) R. Otto, "Frequency modulation by means of acapacitor with controlled charging cycle," Frequenz, vol. 5, pp. 323-327; November-December, 1951.
(435) E. Kettle, "New master oscillator of high frequency stability for FM USW broadcast transmitters," Telefunken Z., vol. 25, pp. 60-64; March, 1952.
(436) E. Kettle, "New control transmitter of high frequency stability for ultra-short wave, FM broadcast transmitters," Telefunken Z., vol. 25, pp. 60-64; March, 1952.
(437) E. Roessler, "Effect of the pilot transmitter," Fernmeldtech. Z., vol. 5, pp. 97-100; March, 1952.
Television
The various panels of the National Television System Committee (NTSC) in the United States made continued progress towards the eventual development of a compatible color-television system. A number of manufacturers and networks began experimentally to transmit NTSC color signals for limited field testing.
The research laboratories throughout the television industry in the United States were busily engaged in the development of experimental color equipment. The recently developed color flying-spot scanners were already in limited use in research and development programs in the industry.
Of academic interest, was the release by NTSC of a glossary of color-television terms, these working definitions being widely circulated for the benefit of those currently engaged in color work.
(438) B. D. Loughlin, "Recent improvements in band-shared simultaneous color television," PROC. I.R.E., vol. 39, pts. Iand II, pp. 1264-1279; October, 1951.
(439) N. Marchand, H. R. Holloway, and M. Leifer, "Analysis of dot-sequential color television," PROC. I.R.E., vol. 39, pp. 1280-1287; October, 1951.
(440) P. C. Goldmark, J. W. Christensen, and J. J. Revees, "Color television--U. S. A. standard," PROC. I.R.E., vol. 39, pp. 12881313; October, 1951.
(441) R. B. Dome, "Spectrum utilization in color television," Pxoc. I.R.E., vol. 39, pp. 1323-1331; October, 1951.
(442) K. McIlwain, 92equisite color bandwidth for simultaneous color-television systems," PROC. I.R.E., vol. 40, pp. 909-912; August, 1952.
(443) E. G. Ramberg, "Elimination of moiré effects in tri-color kinescopes," PROC. I.R.E., vol. 40, pp. 916-922; August, 1952.
(444) K. Schlesinger and L. W. Nero, "Pt phase indicator for color
television," Electronics, vol. 25, p. 112; October, 1952.
(445) S. Applebaum, "Gamma Correction in Constant-Luminance Color-Television Systems," presented at IRE National Convention, New York, N. Y.; March 4, 1952.
(446) D. C. Livingston, "Theory of symchronous demodulator as used in NTSC color television receiver," Sylv. Tech., vol. 5, pp. 60-63; July, 1952.
(447) S. W. Moulton, "Colorimetric Measurements in Color Television," presented at the IRE National Convention, New York, N. Y.; March 4, 1952.
(448) D. Richman, "Frame Synchronization for Color Television," presented at the IRE National Convention, New York, N. Y.; March 4, 1952.
(449) F. J. Bingley, "Colorimetric Electronics," presented at the IRE National Convention, New York, N. Y.; March 4, 1952.
(450) J. Fisher, "The Generation of Compatbile Color Signals for Research and Testing," presented at the IRE National Convention, New York, N. Y.; March 4, 1952.
(451) G. R. Tingley, R. D. Thompson, and J. H. Haines, "A Universal Scanner for Color Television," presented at the IRE National Convention, New York, N. Y.; March 4, 1952.
(452) W. F. Bailey, "Vestigial-Sideband Transmission of the Color Subcarrier in NTSC Color Television," presented at the IRE National Convention, New York, N. Y.; March 4, 1952.
(453) "Definitions for color TV," Electronics, vol. 25, p. 208; Nov., 1952.
(454) C. J. Hirsch, W. F. Bailey, and B. D. Loughlin, "Principles of NTSC compatible color television," Electronics, vol. 25, pp. 88-95; February, 1952.
(455) R. B. Dome, "NTSC color-TV synchronizing signal,» Electronics, vol. 25, pp. 96-97; February, 1952.

An important device, the Eidophor, was demonstrated for large-screen theatre television. Further interest in larger home television pictures led to active development of the 27-inch wide-angle picture tube.
(456) E. Baumann, "The Fischer large-screen projection system," Jour. Brit. I.R.E., vol. 12, pp. 69-78; February, 1952.
(457) C. E. Torsch, "Ninety Degree Cathode-Ray Sweep System Consuming Less Than 'Fifty Degree' Power," IRE Fall Meeting, Syracuse, N. Y.; October, 1952.
Improved methods of rapidly measuring phase and frequency response of television systems were discussed. Better methods of reproducing moving-picture film for television were demonstrated using flying-spot scanners with steady motion of the film.
(458) E. D. Goodale, "Phase, Amplitude and Aperture Correction in Television Systems," IRE Convention, Cincinnati, Ohio; · April, 1952.
(459) T. C. Nuttal, "The development of ahigh-quality 35 mm film scanner,» Proc. IEE (London), Pt. IIIA, pp. 136-144, 174178; 1952.
A proposal for a "light" amplifier for television pictures was discussed. Demonstrations were given of experimental television receivers using transistors.
(460) "Electronic light amplifiers for TV," Tele-Tech, vol. 11, pp. 41, 110, 112; July, 1952.
(461) "Portable television receiver," Sci. Newsletter, p. 392; Novem- · ber 29, 1952.
Methods of obtaining stereoscopic television were developed. Further work was done in improving synchronization and interlace of television receivers.
(462) V. K. Zorykin and L. E. Flory, "Television in medicine and biology," Elec. Eng., vol. 47, pp. 40-45; January, 1952.
(463) G. B. Townsend, "On overcoming the non-interlacing of television receivers which are accurately synchronized," Proc. IEE (London), pt. 3A, II IA, vol. 99, pp. 645-650; 1952.
(464) A. W. Keen, "A Precision Synchronizing System for Large'Screen Television Equipment," Institution of Electrical Engineers, Paper 1344, 12 pp.; 1952.
(465) M. Marks, "Noise-immune sync. separator," Electronics, vol. 25, pp. 124-127; April, 1952.
(466) G. N. Patchett, "Faulty interlacing," Wireless World, vol. LVIII, pp. 250-254; July, 1952.
A new sweep generator tunable over the whole uhf and vhf band at fundamental frequency and with relatively large output became commercially available. Further studies of IF and video-amplifier characteristics leading toward linear phase response were made.
(467) H. A. Finke and F. Blecher, "Wideband sweep generator for VHF and UHF TV,» Tele-Tech, vol. 11, pp. 52-54; August, 1952.
(468) H. Kiehne and S. Mazur, "Phase-linear television receivers," Electronics, vol. 25, pp. 103-105; May, 1952.
To reduce the visibility of line structure on large picture tubes, there was described amethod of vertical "spot stretching." Improvements in gamma-control amplifier circuits were described while a useful multiplechannel-output laboratory television source became commercially available.
(469) G. N. Patchett, "Line eliminator," Wireless World, vol. LVII1, pp. 219-221; June, 1952.
(470) L. Lax and D. Weighton, "A Gamma-Control Circuit Using Crystal Diodes,» Institution of Electrical Engineers, Paper 1308, 7pp.; 1952.
(471) S. R. Patremio, "The Du-Mitter," Radio Electronic Engineering, vol. 31, pp. 3-5; February, 1952.

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Receivers
The quantity of new material covering home-entertainment receivers has been greatly reduced as aresult of conversion to defense orders.
The use of printed circuits has been extended to small radio receivers and to sections of television receivers. A major advance in assembly-line technique has been the introduction of adip-soldering process whereby several hundred connections are soldered simultaneously.
(472) W. A. Tervell, "Printed circuit design methods and assembly techniques," Tetes. Eng., vol. 3, pt. I, pp. 10-12; February, 1952; pt. II, pp. 19, 29; March, 1952.
(473) W. H. Hannahs and N. Stein, "Printed unit assemblies for TV," Tele-Tech, vol. 11, pp. 38-40; June, 1952.
(474) E. Wavering, "Printed circuits for radio receivers," Electronics, vol. 25, pp. 140-142; November, 1952.
(475) "Plated circuit process for radio production," Tele-Tech, vol. 11, pp. 56-57; November, 1952.
Transistors are being used in the laboratory to replace conventional tubes in television, in AM radio, in FM radio, in personal and auto radios, and in phonograph oscillators. The November, 1952 issue of the PROCEEDINGS OF THE I.R.E.is devoted to 48 articles on trans-
istors. Some of these are continuously variable for complete
coverage of the uhf band and others are turret designs with strips for both vhf and uhf channels. Many circuit variations have been employed, some using harmonics of the oscillator for frequency conversion and some having double and others with single conversion with a wide range of intermediate frequencies. Recent designs trend toward the use of somewhat simpler and more conventional circuitry with fundamental oscillator operation and single conversion to the standard 41.25-mc and 45.75-mc sound and picture intermediate frequencies. With progress in receiving tube development for uhf amplifier and oscillator application, circuit development has been directed toward the addition of an
amplifier stage preceding the mixer.
(476) H. Hesse, "A new uhf television converter," Tele-Tech, vol. 11, pp. 36-39 and 114, 116, 118; March, 1952.
(477) T. Murakami, "A study of grounded-grid uhf amplifiers," RCA Rev., vol. 12, pp. 682-701; December, 1951.
(478) Wen Yuan Pan, "Relative magnitudes of undesired responses in uhf receivers," RCA Rev., vol. 12, pp. 660-681; December, 1951.
(479) E. G. Hamer and L. J. Herbst, "Receivers for use at 460 mc/s," Wireless Eng., vol. 28, pp. 323-329; November, 1951.
(480) E. E. Harris and M. Cawein, "Concentric lines tune uhf channels," Electronics, vol. 25, pp. 108-112; February, 1952.
(481) S. R. Scheiner and G. W. Carter, "Measuring uhf receiver noise figures," Electronics, vol. 25, pp. 128-129; March, 1952.
(482) H. F. Reith, "Performance and design of a compact uhf tuner," Tele-Tech, vol. 11, pp. 42-43, 76, 78, 80; August, 1952.
(483) H. A. Finke and S. Deutsch, "Combination uhf-vhf television tuner," Tele-Tech, vol. 11, pp. 58-59 and 176-180; September, 1952.
(484) W. B. Whalley, "Design considerations for uhf and vhf receivers," Tele-Tech, vol. 11, pp. 36-38 and 104, 106, 108, 110; November, 1952.
(485) "Tele-Tech's guide to latest uhf receiving tubes," Tele-Tech, vol. 11, p. 92; November, 1952.
New items of measuring and test equipment for use in the 470-890-mc television band were developed. Two
types of sweep frequency generators necessary for laboratory development and production testing of uhf television receivers appeared.

(486) J. A. Cornell, and J. F. Sterner, "Sweep frequency generator for uhf television band," Tele-Tech. vol. 11, pp. 38-40, 86, and 88; February, 1952.
(487) H. A. Finke and F. Blecher, "Wideband sweep generator for vhf and uhf television," Tele-Tech, vol. 11, pp. 52-54 and 75; August, 1952.
Work on uhf receiving antennas for home installation continued with emphasis on design simplification and field measurements of directivity, bandwidth, and gain over the uhf frequency band. Various types include single and stacked fan dipoles; single and stacked rhombics; stacked V; sheet, paraboloidal, and corner reflectors; and Yagi arrays. For home antenna installations a300-ohm transmission line with low losses (particularly when wet), has two parallel Copperweld 22gauge wires each centered by spiral polyethylene threads in a polyethylene tube, the whole covered by a polyethylene sheath.
Fig. 5--Dip-soldered radio chassis (L), compared with handsoldered counterpart. (General Electric Co.)
(488) E. O. Johnson and J. D. Callaghan, "Receiving antennas for uhf television," Tele-Tech, vol. 10, pp. 38-41 and 82; December, 1951.
(489) E. O. Johnson and J. D. Callaghan, "UHF receiving antennas," Electronics, vol. 25, pp. 132 and 134; January, 1952.
(490) "New uhf television transmission line," Tele-Tech, vol. 11, pp. 150 and 153; December, 1952.
The appearance of larger picture tubes with wideangle deflection has stimulated progress in the design of sweep circuits.
(491) B. M. Cole, "Improved horizontal TV sweep circuits," TeleTech, vol. 11, pp. 92-93; September, 1952.
(492) C. E. Torsch, "Ninety-Degree Cathode Ray Sweep System Consuming Less than 'Fifty-Degree' Power," presented at IRE/RTMA Fall Meeting; October, 1952.
Activity has continued in the development of methods for improving picture sharpness that is directly related to the receiver transient response. It has been suggested that the receiver phase response be made linear. The quadrature component affects the transient response adversely and amethod for reducing it by use of areceiver with astep type of amplitude response has been described.
(493) H. Kiehne and S. Mazur, "Phase-linear television receivers," Electronics, vol. 25, pp. 103-105; May, 1952.
(494) J. Ruston, "Improved TV system transient response," Electronics, vol. 25, pp. 110-113; August, 1952.

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April

There is an increasing trend toward incorporating circuits for cancellation of large noise peaks in the synchronizing circuit. With ordinary limiting, large noise peaks tend to make the sync separator inoperative for a short time after their occurrence.
(495) M. Marks, "Noise-immune sync separator," Electronics, vol. 25, pp. 124-127; April, 1952.
The problems of television interference continue to receive attention. In Canada, where interference regulations are more strict, the design of receivers is especially difficult.
(496) W. B. Smith, Canadian Dept. of Transport, "Problems of television interference," presented at IRE/RTMA Fall Meeting; October, 1952.
Progress was made in the reduction of oscillator radiation, and most receivers now being sold are within the limits of RTMA standard REC-129C. The selection of sites for radiation measurements are discussed in an IRE report.
(497) "Practical considerations in measuring vhf receiver oscillator radiation," supplement to 51 IRE 17S1.
(498) E. W. Chapin and W. K. Roberts, "Reducing TV receiver oscillator radiation," Electronics, vol. 25; pp. 116-120; July, 1952.
The IRE Subcommittee on Spurious Radiation is working on apreliminary standard for sweep radiation measurements.
Although the industry has been preparing for uhf for some time the feverish activity started when station KPTV in Portland, Oregon began commercial uhf broadcasting in September, 1952. Improving the noise performance and noise-measurement technique of uhf amplifiers continued to be amajor objective. Noise figures for uhf tuners are 10-15 db higher than for vhf tuners.
(499) S. R. Scheiner, and G. W. Carter, "Measuring UHF-TV rereceiver noise figures," Electronics, vol. 25, pp. 128-129; March, 1952.
(500) A. B. Glenn, "Study of noise reduction by feedback in ultrahigh frequency amplifiers," presented at IRE/RTMA Fall Meeting; October, 1952.
A multitude of new types of tuners and converters were reported. These vary in complexity from a onechannel converter to an 82-channel turret tuner, using distributed or lumped elements, single or double conversion, and avariety of mechanical designs. (5w) R. G. Peters, "Ultra-high tuner, converter and receiver re-
search and design," TV Eng., vol. 3, pp. 6-9; April, 1952. (502) W. B. Whalley, "Design considerations for combination UHF
and VHF receivers," Tele-Tech, vol. 11, pp. 36-38; November, 1952. (503) N. Edwards, "UHF Conversion methods," Radio and Telev. News, vol. 47, pp. 56-58; June, 1952; vol. 48, pp. 47-49; July, 1952. (504) E. E. Harries and M. Cawein, "Concentric lines tune UHF channels," Electronics, vol. 24, pp. 108-112; 1952.
Facsimile
A facsimile system to handle interoffice correspondence in connection with television broadcasting systems operations was placed in service. This system provides a reproduction rate of 28 square inches per minute at 105-line definition over an 8-kc channel by vestigialsideband operation employing linear phase filters.

The use of facsimile for terminal handling of regular traffic in commercial telegraph systems continued to increase with some 6,900 "Desk-Fax" units in operation in United States cities, connecting patrons directly with the nearest central office. In addition, this facility was provided nearly 100 subscribers in London, England to expedite the handling of cablegrams.
To speed communications within large commercial organizations a similar system, "Intrafax," has been developed. This system employs the basic transmitter and recorder units in a flexible arrangement adaptable to the needs of each individual organization. Several such private systems were placed in operation during the year.
Further information has been made available on Western Union's new high-speed facsimile system.
(505) "London inaugurates facsimile service," Tele. and Tele. Age, vol. 4, p. 21; April, 1952.
(506) H. H. Haglund, "Thirty-line concentrator for private facsimile systems," Western Union Tech. Rev., vol. 6, pp. 143-144; October, 1952.
(507) C. R. Deibert, F. T. Turner, and R. H. Snider, "A high-speed direct-scanning facsimile system," Western Union Tech. Rev., vol. 6, pp. 37-46; April, 1952.
(508) D. M. Zabriskie, "A high-speed telefax recorder," Western Union Tech. Rev., vol. 6, pp. 48-55; April, 1952.
(509) L. G. Pollard, "A high-speed facsimile transmitter," Western Union Tech. Rev., vol. 6, pp. 56-60; April, 1952.
Recent developments in the graphic arts which may have a significant effect upon progress in the field of facsimile and which have already stimulated considerable research activity include zerography, and more recently, ferrography and ferromagnetography. These latter two involve the use of the familiar magneticcoated tape or sheet and means for rendering the magnetic image visible. All would seem to present bases for the development of new facsimile recording and storage techniques.
(510) R. B. Atkinson and S. G. Ellis, "Ferrography," Jour. Frank. Inst., vol. 252, pp. 373-381; November, 1951.
(511) T. M. Berry and J. P. Hanna, "Ferromagnetrography, high speed printing with shaped magnetic fields," Gen. Elec. Rev., vol. 55, no. 4, pp. 20-22,61; July, 1952.
Industrial Electronics
Magnetic Amplifiers
In the last two years, a rapid growth of interest in magnetic amplifiers has materialized among practicing engineers.
(512) W. J. Dornhoefer and V. H. Krumnenacher, "Applying magnetic amplifiers," Elec. Mfg., March, April, August, September, 1951. Reprints available.
(513) L. A. Finzi and G. F. Pitman, Jr., "A Critical Comparison of Methods of Analysis of Magnetic Amplifiers," presented at National Electronics Conference; September 29,1952.
A practical understanding of circuit operation and design procedure based on the relations between performance and circuit parameters, while known to those developing magnetic-amplifier techniques, had appeared in the technical literature only by implication prior to the publishing of the reference listed below.
(514) J. T. Carleton and W. F. Horton, "The Figure of Merit of Magnetic Amplifiers," AIEE Communication and Electronics; September, 1952.

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Radio Progress During 1952

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Many groups are interested in the application of magnetic amplifiers to servomechanisms, and valuable experience was gained in circuit techniques.
(515) W. A. Geyger, "A New Type of Magnetic Servo Amplifier," ALEE Communications and Electronics; September, 1952.
(516) C. W. Lufey, A. E. Schmid, and P. W. Barnhart, "An improved magnetic servo amplifier," ALEE Communications and Electronics; September, 1952.
Others recognized the applicability of magnetic amplifiers to the solution of difficult measurement problems.
(517) W. A. Geyger, "Magnetic Amplifiers of the Self-Balancing Potentiometer Type," AIEE Technical paper 52-271, presented, ALEE Fall General Meeting, New Orleans, La.; October 15,1952.
(518) G. M. E. Hinger, "A magnetic amplifier of high input impedance," Proc. NEC, (Chicago), vol. 7, p. 523; 1951.
The problem of stability, or drift, of amplifiers is recognized as one of the most formidable. It is essentially this problem that is dealt within measurements and in detection of small signals. It seems to be widely agreed that the limitations are imposed by the characteristics of the receivers and that the stability of the magnetic amplifier in practical circuitry is not appreciably better than that of the vacuum tube.

(522) L. A. Pipes, "A mathematical analysis of a dielectric amplifier," Jour. Ape Phys. vol. 23, pp. 818-824; August, 1952.
(523) H. Urkovitz, "A ferroelectric amplifier," Report No. 199M, Philco Research Division; March, 1952.
(524) A. M. Vincent, "Dielectric amplifier fundamentals," Electronics, vol. 24, pp. 84-88; December, 1951.
In general, slow progress is being made in the search for new nonlinear dielectric materials, such as the niobates and zurconates, and in improving the titanates in an effort to obtain more thermally stable dielectrics. A possible new class of such dielectrics consisting of colloidal mixtures of dielectrics suspended in insulating oils, or in gels, has been reported, with emphasis, however, on the sensitive rather than dielectric properties.
(525) H. E. Hollman, "Polaresistivity and polaristors," PROC. I.R.E., vol. 40, pp. 538-545; May, 1952.
Electronic Computers
Large-Scale Machines
An increasing number of large-scale computers was put into operation in the United States to speed up the nation's defense effort.
(526) C. R. Strang, "Computing machines in aircraft engineering," Rev. Electronic Digital Computers, pp. 94-101; February, 1952 .

Nonlinear Dielectrics
Notable progress has been made in the application of nonlinear dielectrics to storage and low-frequency amplifiers.
Single barium titanate crystals of useful size are now being grown in several university, industrial, and mili-

Large electronic digital computers received most attention. The characteristics of completed machines and their operating experience were the subjects of aJoint AIEE-IRE Electronic Computer Conference held in Philadelphia in December, 1951. This conference included papers by the users of the machines as well as by

tary laboratories. Thin slabs of such single crystals have

been used for ferroelectric storage in digital computers.

It is estimated that for storage rates of 106 binary digits

per second using 20.5 mw read-in power, 2.8 mw read-

out power can be obtained. Simplicity of construction

and concentration of information are outstanding fea-

tures. Work is continuing using polycrystalline ti -

tanates, with, however, less spectacular results.

(519) J. R. Anderson "Ferroelectric storage elements for digital computers and switching systems," Elec. Eng., vol. 71, pp. 916-922; October, 1952.
(520) W. N. Papian, "Ferromagnetic and Ferroelectric Memory Devices," Engineering Note E-470, Digital Computer Laboratory, M.I.T. Cambridge, Mass.; August, 1952.
(521) A. von Hippel, "Piezoelectricity, Ferroelectricity and Crystal Structure," Report dated Mar. 1952, on O.N.R. contracts, N5-ori-0780I, N5 ori-07858. Laboratory for Insulation Research, M.I.T., Cambridge, Mass.

The analysis of low-frequency dielectric amplifiers circuits has been attacked by several approximate methods. In one, the curve of electric displacement versus applied electric intensity is approximated by a hyperbolic sine function; in another method, a power series is used. With suitable simplifying assumptions, solutions to the nonlinear differential equations have been obtained, yielding useful relations for design pur-
poses. Audio-frequency amplifiers have been built at the
PhiIco Corporation and at Carnegie Institute of Technology, the latter having achieved outputs of approximately 1watt with efficiencies exceeding 25 per cent.

Fig. 6--Mr. Arthur F. Draper, who is in charge of new products research for Remington Rand, shown at the microphone of the UNIVAC on election night.
the designers. An example of the advanced state of development, as compared with the period only several years ago when most large-scale machines were in the hands of their designers, is the Univac, a high-speed serial machine employing elaborate checking devices and designed for both scientific and business applications. In addition, it is the first digital-computer system with extensive input-output equipment, utilizing from one to ten magnetic-tape units for high-speed input and output transfers. There is an array of auxiliary equip-

474

PROCEEDINGS OF THE I.R.E.

April

ment including keyboard-to-tape and punched-card-totape converters and printing devices, all of which function independently of the central computer. The Univac is the first computer to be manufactured on aproduction basis and several have already passed acceptance tests.
(527) J. P. Eckert, Jr., J. R. Weiner, H. F. Welsh, and H. F. Mitchell, "The UN IVAC system," Rev. Electronic Digital Computers, pp. 6-15; February, 1952.
(528) J. L. McPherson and S. N. Alexander, "Performance of the census UNIVAC," Rev. Electronic Digital Computers, pp. 1620; February, 1952.

arithmetic unit, and magnetic-tape input-output equipment.
The Harvard University Mark IV, a serial decimal machine employing magnetic-drum memory and magnetic-core shifting registers, was put in operation.
Another ·machine of considerable importance was finished, an engineering prototype of the IBM type 701 calculator. This computer contains alarge electrostatic memory of the Williams type and is notable for its extensive input-output facilities. .
(532) M. M. Astrahan and N. Rochester, "The logical organization of the new IBM scientific calculator," Proc. Assoc. Computing Machinery, pp. 79-83; 1952.

The M.I.T. Whirlwind Icomputer, avery high-speed calculator using an electrostatic storage tube of special design, was used for scientific, engineering, and military computation.
(533) R. R. Everett, "The Whirlwind I Computer," Elec. Eng., vol. 71, pp. 681-686; August, 1952.
(534) N. H. Taylor, "Evaluation of the engineering aspects of Whirlwind I," Rev. Electronic Digital Computers, pp. 75-83; February, 1952.

The National Bureau of Standards Eastern Automatic Computer now has over two years of scheduled operating experience on an extremely wide variety of problems from all parts of government.
(535) S. N. Alexander, "The National Bureau of Standards Eastern Automatic Computer," Rev. Electronic Digital Computers, pp. 84-89; February, 1952.
(536) R. J. Slutz, "Engineering experience with the SEAC," Rev. Electronic Digital Computers, pp. 90-93; February, 1952.

Fig. 7--General Electric engineers Earl Theall, (kneeling) and Bernard Geyer inspect parts of General Electric's new digital computer, "OARAC," developed by G.E. for the Air Force's Research and Development Command. The central panel of the OARAC, used primarily for testing purposes, is flanked on either side by rows of plug-in turrets containing most of the 1,400 tubes and many of the 7,000 diodes used in this giant computer.
Several machines of the Institute for Advanced Study type were put in operation. These are high-speed parallel binary machines using Williams' electrostatictube memories. The Ordvac, the first of these machines to be put in operation, was delivered by the University of Illinois to the Ballistic Research Laboratories of Aberdeen Proving Grounds. A similar computer with aphotoelectric-tape reader and ahigh-speed punch was completed at the University of Illinois.
(529) R. E. Meagher and J. P. Nash, "The Ordvac," Rev. Electronic Digital Computers, pp. 37-42; February, 1952.
(530) G. Estrin, "A description of the Electronic Computer at the Institute for Advanced Studies," presented Association for Computing Machinery, Toronto; September 8, 1952.
(531) N. Metropolis, E. F. Klein, W. Orvedahl, J. R. Richardson, H. H. Demuth, and J. B. Jackson, "Maniac," presented Association for Computing Machinery, Toronto; September 8, 1952.
The Raydac, designed and constructed by the Raytheon Manufacturing Company, passed its acceptance tests. It employs a serial acoustic memory, parallel

Three variations of this type of machine, extensively repackaged, are being constructed at the National Bureau of Standards and elsewhere.
The National Bureau of Standards Western Automatic Computer located at UCLA, a parallel machine using Williams memory, was able to perform considerable useful computation while undergoing engineering improvements.
The Edvac, a serial-binary machine using mercuryacoustic delay-line memory and designed and constructed at the Moore School of Electrical Engineering at the University of Pennsylvania, was put into regular production service at the Aberdeen Proving Grounds.
A high degree of reliability was obtained with the ERA 1101 computer, a large-scale machine employing amagnetic-drum memory.
(537) F. C. Mullaney, "Design features of the ERA 1101 Computer," Rev. Electronic Digital Computers, pp. 43-48; February, 1952.
A background of operating experience with many other large-scale digital computers became available.
(538) E. G. Andrews, "A review of the Bell Laboratories' digital computer development," Rev. Electronic Digital Computers, pp. 101-105; February, 1952.
(539) G. E. Poorte, "The operation and logic of the MARK III electronic calculator in view of operating experience," Rev. Electronic Digital Computers, pp. 50-55; February, 1952.
(540) G. G. Hoberg, "The Burroughs Laboratory computer," Rev. Electronic Digital Computers, pp. 22-29; February, 1952.
(541) A. A. Auerbach, J. P. Eckert, Jr., F. R. Shaw, J. R. Weiner, and L. D. Wilson, "The Binac," PROC. I.R.E., vol. 40, pp. 1229; January, 1952.
(542) J. W. Sheldon and L. Tatum, "The IBM card-programmed

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Radio Progress During 1952

475

electronic calculator," Rev. Electronic Digital Computers, pp. 30-36; February, 1952. (543) F. C. Williams and T. Kilburn, "The University of Manchester computing machine," Rev. Electronic Digital Computers, pp. 57-61; February, 1952. (544) B. W. Pollard, "The design, construction, and performance of alarge-scale general-purpose digital computer," Rev. Electronic
Digital Computers, pp. 62-69; February, 1952.
(545) A. D. Booth, "The physical realization of an electronic digital computer," Elec. Eng. (London), vol. 24, pp. 442-445; October, 1952.
(546) T. Pearcey, "An automatic computer in Australia," Mathematical Tables and other Aid to Computation, vol. 6, pp. 167172; July, 1952.
Two excellent review articles appeared, one emphasizing applications, the other engineering developments.
(547) M. Rees, "Digital Computers--their nature and use,» Amer. Sci., vol. 40, pp. 328-335; April, 1952.
(548) J. W. Forrester, "Digital computers: present and future trends," Rev. Electronic Digital Computers, pp. 109-113; February, 1952.

having magnetic-drum memories, requiring less than 10-kw total power, and costing from $50,000 to $100,000.
(550) D. H. Jacobs, "The JAINCOMP-BI Computer," presented Symposium on Commercially Available General-Purpose Electronic Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.
(551) E. J. Quinby, "The MONROBOT Electronic Calculators," presented Symposium on Commercially Available Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.
(552) R. E. Sprague, "The CADAC," presented Symposium on Commercially Available Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.
(553) J. Greig, "The Circle Computer," presented Symposium on Commercially Available Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.
(554) A. Auerbach, "The Elecom 100," presented Symposium on Commercially Available Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.
(555) L. P. Robinson, "Model 30-201 Electronic Digital Computer," presented Symposium on Commercially Available Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.
(556) G. B. Greene, "The Miniac," presented Symposium on Commercially Available Digital Computers of Moderate Price, Pentagon, Washington, D. C.; May 14, 1952.

Special Computers

The Maddida and other digital differential analyzers appeared and carne into wide use. A magnetic-drum memory and electronic digital techniques were used in this small machine, providing greater flexibility and precision than conventional differential analyzers.
(557) J. F. Donan, "The serial-memory digital differential analyzer," Mathematical Tables and other Aids to Computation, vol. 6, pp. 102-112; April, 1952.
(558) R. E. Sprague, "Fundamental concepts of the digital differential analyzer method of computation," Mathematical Tables and other Aids to Computation, vol. 6, pp. 41-49; January, 1952

Fig. 8--The Typhoon Co.nputer, developed and built by the RCA Laboratories Division of the Radio Corporation of America, in operation at the Naval Air Development Center at Johnsville, Pennsylvania. The Typhoon has extreme flexibility of design, and has been adapted to unusual uses.
The Typhoon computer, developed and built by RCA Laboratories, was moved to the Naval Air Development Center at Johnsville, Pennsylvania. It is believed to be the largest and most accurate analog computing system in use at the present time. It features new electronic computing devices, such as the stabilized dc amplifier, the step multiplier, and the time-division multiplier.
(549) E. A. Goldberg, "A high-accuracy time-division multiplier,» Electronics, vol. 13, pp. 265-274; September, 1952.
Although originally designed as a missile simulator, Typhoon is currently employed for studying in threedimensional form the performance of a piloted aircraft with associated maneuver autopilot. The fact that Typhoon was readily adapted for this problem verifies the flexibility of the design.
Commercial Digital Computers of Moderate Price
Commercially available general-purpose electronic digital computers of moderate price were the subjects of a symposium held at the Pentagon in Washington, D. C., on May 14, 1952. These are small serial machines

The use of both digital and analog computers for simulation and control is a subject of vital interest. A mixture of analog and digital techniques is frequently useful.
(559) H. H. Goode, "Simulation--its place in system design," Pkoc. I.R.E. vol. 39, pp. 1501-1506; December, 1951.
(560) B. M. Gordon and R. N. Nicola, "Special-purpose digital data-processing computers," Proc. Assoc. Computing Machinery, pp. 33-45; 1952.
(561) M. J. Mendelson, "The quadratic arc computer," Proc. Assoc. Computing Machinery, pp. 53-59; 1952.
Many analog computers, varying widely in complexity and application, were developed.
(562) E. A. Baldini and A. P. Fugill, "Power system analogue and network computer," Elec. Eng., vol. 71, p. 439; May, 1952.
(563) F. W. Bubb, Jr., "Circuit for generating polynomials and finding their zeroes," PROC. I.R.E., vol. 39, pp. 1556-1561; December, 1951.
(564) G. A. Korn, "The difference analyzer: a simple differential equation solver," Mathematical Tables and other Aids to Computation, vol. 6, pp. 1-8; January, 1952.
(565) B. B. Young, "Advanced time scale analog computer," Jour. Frank. Inst., vol. 253, pp. 169-271; Fall, 1952.
Components and Techniques
The reliability of vaccum tubes for use in large-scale computers is asubject of primary concern that has received little attention in the literature. One important study, based on 2,500,000 electron-tube sockets in the field and atwo-year program of defective-tube analysis, was published.

476

PROCEEDINGS OF THE I.R.E.

April

(566) J. A. Goetz and A. W. Brook, "Electron tube experience in
computing equipment," Elec. Eng., vol. 71, pp. 154-157;
February, 1952.
The most important engineering problem continues to be that of how to make the memory. The most widely used high-speed memory at the present time is the electrostatic storage tube. A number of important papers reflecting abetter understanding of the processes involved appeared. Several of these described important improvements in the Williams type of memory including acathode-ray tube specifically designed for the purpose.
(567) A. Robinson, "The testing of cathode ray tubes for use in the Williams type storage system," presented Association for Computing Machinery, Toronto; September 9, 1952.
(568) A. J. Lephakis, "Electrostatic-tube storage system," PROC. I.R.E., vol. 39, pp. 1413-1415; November, 1951.
(569) W. E. Mutter, "Improved cathode-ray tube for application in Williams memory system," Elec. Eng., vol. 71, pp. 352-356; April, 1952.
(570) R. Schumann, "Improvement of Williams memory reliability," presented Association for Computing Machinery, Toronto; September 9,1952.
(571) B. Kazan and M. Knoll, "Fundamental processes in chargecontrolled storage tubes," RCA Rev., vol. 12, pp. 702-753; December, 1951.
Perhaps the most important technical development for the digital computer field was the use of ferromagnetic or ferroelectric materials with rectangular hysteresis loops for high-speed random-access memory. These techniques offer the possibility of extremely reliable large-capacity memories with access times of the order of microseconds.
(572) J. A. Rajchmann, "Static magnetic matrix memory and switching circuits," RCA Rev., vol. 13, pp. 183-201; June, 1952.
(573) W. N. Papian, "A coincident-current magnetic memory cell for the storage of digital information," PROC. I.R.E., vol. 40, pp. 475-478; April, 1952.
(574) J. R. Anderson, "Ferroelectric storage for digital computers and switching systems," Elec. Eng., vol. 71, pp. 916-922; October, 1952.
(575) I. L. Auerbach, "A static magnetic memory system for the ENIAC," Proc. Assoc. Computing Machinery, 1952, pp. 213222.
Other memory techniques have been stimulated by the development of new materials.
(576) A. E. DeBarr, R. Millership, P. F. Dorey, R. C. Robbins, and P. D. Atkinson, "Digital storage using ferromagnetic materials," Proc. Assoc. Computing Machinery, pp. 197-202; 1952.
(577) A. Wang, "Static magnetic memory--its applications to computers and controlling systems," Proc. Assoc. Computing Machinery, pp. 207-212; 1952.
(578) N. B. Saunders, "Magnetic binaries in the logical design of information handling machines," Proc. Assoc. Computing Machinery, pp. 223-229; 1952.
(579) T. F. Rogers and W. A. Anderson, "Some recent research on ultrasonic propagation in solid media," Proc. Assoc. Computing Machinery, pp. 203-205; 1952.
(580) A. W. Holt, "A very rapid access memory using diodes and capacitors," presented, IRE National Convention, New York, N. Y.; March 6,1952.
(581) A. W. Holt, "Progress report on avery rapid access memory using diodes and capacitors," presented Association for Computing Machinery, Toronto; September 9,1952.
(582) J. Rabinow, "The notched disk memory," Elec. Eng., vol. 71, pp. 745-749; August, 1952.
(583) I-1. L. Daniels, "Boundary displacement recording," Electronics, vol. 25, pp. 116-120; April, 1952.
The point-contact transistor was reported as being admirably suited for application in high-speed pulse circuits. (584) J. H. Felker, "The transistor as a digital computer com-
ponent," Rev. Electronic Digital Computers, pp. 105-108; February, 1952.

(585) R. L. Trent, "Binary counter uses two transistors," Electronics, vol. 25, pp. 100-101; July, 1952.
Besides the transistor, many other new components for arithmetic and control circuits were reported.
(586) F. A. Schwertz and B. Moffat, "Nonlinear switching elements," Proc. Assoc. Computing Machinery, pp. 143-157; 1952.
(587) C. Isborn, "Ferroresonant flip-flops," Electronics, vol. 25, pp. 121-123; April, 1952.
(588) R. A. Ramey, "The single core magnetic amplifier as acomputer element," AIEE Technical Paper 52-293.
(589) B. O. Marshall, Jr., F. A. Schwertz, and B. Moffatt, "Optical elements for computers," Proc. Assoc. Computing Machinery, pp. 159-163; 1952.
(590) N. Hardy, "The selenium rectifier--a non-linear and asymmetric resistance element," Proc. Assoc. Computing Machinery, pp. 165-172; 1952.
Other selected references to new techniques are listed.
(591) M. Rubinoff, "Further data on the design of Eccles-Jordan flip-flops," Elec. Eng., vol. 71, pp. 905-910; October, 1952.
(592) D. L. Johnston, "Standardized printed circuit units for digital computers," Proc. Assoc. Computing Machinery, pp. 135-141; 1952.
(593) H. J. Gray, Jr., "Logical description of some digital-computer adders and counters," PROC. I.R.E., vol. 40, pp. 29-33; January, 1952.
(594) R. Weissman, "High-speed counter uses ternary notation," Electronics, vol. 25, pp. 118-121; October, 1952.
(595) J. Broomall and L. Reibman, "Sampling analog computer," PROC. I.R.E., vol. 40, pp. 568-572; May, 1952.
(596) H. J. Geisler, "R-f bursts actuate gas tube switch," Electronics, vol. 25, pp. 104-105; February, 1952.

Input-Output Equipment
Input-output equipment is a subject of increasing importance and many commercial units became available. This equipment was the subject of the Joint AIEEIRE Computer Conference held in New York in December, too late in the year to be included in this report.
(597) J. J. Wild, "High-speed printer for computers and communications," Electronics, vol. 25, pp. 116-120; May, 1952.
(598) J. Lindsmith, "A system for counting and recording electrical impulses in printed decimal form," Proc. Assoc. Computing Machinery, pp. 61-78; 1952.
(599) M. Miller, B. L. Waddell, and J. Patmore, "Digital to analog converter," Electronics, vol. 25, pp. 127-129; October, 1952.

Professional Activities
The IRE Professional Group on Electronic Computers now includes over 1,000 members and has commenced publication of quarterly TRANSACTIONS.
A number of colleges and universities now offer one or more graduate courses in the design and application of electronic digital computers. These include Harvard University, Massachusetts Institute of Technology, University of Pennsylvania, Columbia University, University of Illinois, University of California, Wayne University, and University of Toronto.

Historical

Navigation Aids

The study of patent literature, generously supplemented by the reading of contemporary scientific arti-
cles, provides a systematic procedure for tracing the distant roots of modern technical devices. An interesting example is a report that traces the origins of displays such as the plan position indicator (PPI).

(600)

Cp.p.

D. Tuska, 1-20 and

"Pictorial radio," Jour. Frank. 95-124; January and February,

Inst., 1952.

vol. 253, IRE Ab-

stract 2219.

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Radio Progress During 1952

477

Present Trends
In some recent aircraft, electronic equipment represents 60 per cent of the cost. In guided missiles, the figure may reach 75 per cent. Electronic equipment on amodern fighter represents alarger investment than the entire cost of a comparable World War II fighter. General Ira Eaker therefore emphasizes the great importance of designing a single well-planned electronic system, instead of a jumbled assortment of individual devices. In some cases it may be desirable to design the airplane around the electronic equipment.
Recent descriptions of afighter interceptor illustrate current progress toward automatic operation. The pilot gets the plane into the air and is vectored by ground radar to the general vicinity of the target. Automatic controls then lock on the target, track it, aim the plane, and fire the rockets. The pilot is an interested observer, who is aware of his plane's success when the target's echo vanishes from the cathode-ray-tube screen. The landing is assisted by radio.
Projects designed to decrease the weight of navigational apparatus while preserving reliability have received high priority. Despite current progress, accessory apparatus designed to safeguard a fighting pilot may have the contrary effect in battle. The Russian MiG15 and the American F86 have similar engines and airframe dimensions. Yet the loaded Russian plane weighs 12,500 pounds in comparison with the 16,500-pound U.S. plane, permitting better performance.
Trends in long-distance guided-missile navigation envisage, in advance, the complete computation of anormal flight path. Deviations from normal would be measured by a series of tracking stations along the path and the first-order quantities in these deviations supplied to ahigh-speed digital computer to determine the proper instant for power cut-off and correction of the advance programming of the elevator controls.
Basic Problems
Practically all studies of radio wave propagation are of basic interest in electronic navigation. In cases of fast-moving receivers and transmitters, the dynamic aspects of errors require attention. These include the various effects of Doppler shifts, with attention given to waves reflected from the ground that produce aconsiderable spectrum at the receiver. Errors can be reduced by various forms of integration. The theory of random processes was applied to the study of fluctuations of "ground clutter" in airborne radar. Different kinds of clutter were investigated, and the survey extended to include all kinds of physical phenomena that can result in a radio reflection. Using the principle of inverse probability, information theory was applied to the design of radar receivers.
In view of the world-wide installation of short-distance navigational aids, their maintenance and calibration has assumed great importance. Larger countries maintain special planes with elaborate instrumentation.

Light-weight test gear, quickly installable in a rented plane was designed for intermittent service elsewhere.
(601) H. Busignies, "Dynamic aspects of errors in radio navigational systems," Elec. Commun. (London), vol. 29, pp. 226-228; September, 1952.
(602) "Radio aid accuracy," Flight, vol. LXII, pp. 447-448; October 3, 1952.
Simplified Design
Representative of atrend in simplification of design and construction is apaper on the construction of waveguides by milling slots in block castings, two such cast-
ings being fastened face-to-face in order to close the guide. When this construction is applicable, it is said to be lighter, smaller, cheaper, and better than conven-
tional plumbing. For small planes, a simplified version of the earth-
inductor compass has been designed, using an inexpensive stroboscopic device as the remote indicator. British designers offer alow-cost approach radar giving range and azimuth information only, height being determined by an altimeter. They also propose a-simplified 33-track ground facility, providiné guidance for 100 miles and serving as a localizer for final approach. A relatively inexpensive airborne unit was described making extensive use of delay lines for time discrimination to select the correct ground stations and track. Departures from track are indicated by aleft-right meter.
Specific Applications of Conventional Devices
Several unusual photographs were published, indicating the fine detail obtainable under favorable conditions by the use of K-band radar. This airport-surface-detection-equipment (ASDE) is used solely for directing the "taxi" movement of planes and other vehicles on the runways. Designed primarily for use during low visibility, its remarkably clear presentation assists the controller even in broad daylight, since relative distance can be seen on the radar screen more accurately than it can be estimated by perspective vision. Planes may actually appear in miniature, with wing and fuselage structure, in place of conventional radar's shapeless "blob" of light. Such fine detail stems, of course, from the use of a 1.25-cm wavelength, with an azimuthal beam width of degree.
For commercial flights with jet aircraft, an "anticollision" radar has been designed. This is a 10-kw, 3-cm radar weighing 180 pounds and having a 6-degree beam width. It uses an 18-inch paraboloid, mounted on ahorizontal platform that is servostabilized with respect to a vertical gyro. It scans +75 degrees horizontally while set at angles between +10 degrees vertically, and has a range of 40 miles on dangerous cumulo-nimbus clouds. It may provide guidance through gaps in such clouds and through mountain passes, and is useful as a terrain-clearance indicator. Clouds are considered harmless if they give no response at distances greater than 10 miles. The distance-range on other aircraft is 5 to 15 miles.
For use on Aerobee rockets, aminiature transponder beacon was produced. It occupies a cylindrical space

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PROCEEDINGS OF THE I.R.E.

April

24 inches in diameter, 6 inches long and weighing less than 2pounds. The power supply is of similar size and weight.
In direction finding, the rotatable H-type Adcock retains its popularity. The National Physical Laboratory issued acomprehensive report on the optimum design of the instrument and an analysis of its residual errors. Such errors have been grouped into unbalance, screenimage, and coupling errors. Other papers describe specific designs appropriate to the 26-60-mc, the 300-600mc, and the 30,000-mc frequency ranges.
(603) F. Horner, "An investigation of polarization errors in an HAdcock direction-finder, Proc. IEE (London), pp. 229-240; July, 1952.
Fig. 9--Airport surface-detection equipment radar picture of Idlewild Airfield with aircraft-type DC 6 taxiing on the runway. (Rome Air Development Center).
New Devices While the radar mechanism that procures the data
for a plan-position indicator (PPI) necessarily uses a very short pulse and therefore a very wide radio-frequency spectrum, no such width of spectrum should be necessary to relay the resulting maplike picture to a remote supervisory location. In fact, even a 100-to-1 reduction in bandwidth would be permissible without loss of essential information. In other words, the points of interest on the electronic map change their positions slowly. Hence, any reasonable equivalent of avery slow television scan should suffice. A variety of electronic mechanisms could be devised for such use. During the past year, the Wright-Field group has described a device employing a traveling gate that slides slowly outward along a radial line, the recurrence period of the slow radial sweep being not less than the time required for the radar beam to sweep through abeam width. As it travels, the gate selects informatiom from as many as 100 adjacent and partially overlapping radar sweeps,

thus preserving the essential data while discarding much
of the redundancy. At the receiving point, the data are reassembled in the obvious way by intensity modulation of aslow radial sweep, synchronized with the selecting gate.
A different relay system employs an equivalent, though less obvious, device. Information, displayed on successive high-speed radial sweeps over the original PPI, is also displayed (and integrated) as intensity
modulation on asingle trace that appears on an auxiliary cathode-ray tube. Since this trace may be swept
1,000 times per second (for example), the multitude of coincident lines convey no visible information. However, if the trace be swept optically at slow speed (say 30 scans per second), the derived photocell voltage pattern will alter slightly on successive scans. This change in pattern
results from the slow change of the radar-beam azimuth (at, for example, 10 rpm). Optimum persistence of cathode-ray-tube phosphor depends, of course, on the PPI rotation rate. For convenience of mechanical scanning, the single trace is displayed by arotating-lens method as acircle on the auxiliary tube. At the receiving point, the deflection yoke of acathode-ray tube rotates at 10 rpm, while radial deflection occurs at 30 rps.
Modulation derived from the phototube at the radar site controls the intensity of the radially deflected beam at the distant monitor site, thus reconstructing areasonable facsimile of the original PPI picture. The original video bandwidth was at least 250 kc. The modified video
bandwidth is about 2.3 kc wide, corresponding to 27,000 space elements for each rotation of the radar antenna and the consequent transmission of 4,500 bits per second.
The United States Naval Research Laboratory described adevice called an organ-pipe radar scanner. For rapid scanning purposes, it is frequently desirable that aradar beam shall sweep or oscillate at frequencies far beyond the convenient range of vibration of arelatively
massive object, such as a radar reflector. Hence, it is customary to sweep the radiation source across a focal surface of the paraboloidal reflector, the reflector remaining motionless (or moving slowly for other pur-
poses). Using waveguide techniques, the physical motion of the radiation source may in turn be replaced by an effective motion, as the energy emerges successively from 36 different apertures linearly arrayed across the
focal surface. These output apertures are fed by 36 waveguides, all of equal length. The input apertures are arranged radially in acomplete circle, facing inward so that they receive energy successively from a steadily
rotating electromagnetic horn. To minimize amplitude fluctuations, the output aperture of the horn spans
three adjacent distribution waveguides. To accomplish all of this mechanically with 36 very short (and equal) lengths of waveguide necessarily implies a very neat physical arrangement of the plumbing.
Artificial-horizon devices on the pilot's instrument panel have normally featured a small self-contained gyro. The trend is toward a remote gyro of larger size

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Radio Progress During 1952

479

and greater accuracy integrated with basic navigational aids. The instrument board retains its customary external appearance, but the horizon-bar is positioned by servomotors. In order that fighters shall be operable within two minutes after an alert, the initial erection of the gyro is assisted and speeded by aspecial motor operated by agravity-controlled switch that senses gross departures from the desired vertical axis.
(604) W. Otto, "Radar signal sampler compresses bandwidth," Electronics, vol. 25, pp. 132-135; April, 1952. IRE Abstract 1921.
(605) J. L. McLucas, "Narrow-band link relays radar data,» Electronics, vol. 25, pp. 142-146; September, 1952.
(606) K. S. Kelleher and H. H. Hibbs, "Organ-pipe radar scanner,» Electronics, vol. 25, pp. 126-127; May, 1952. IRE Abstract 1920.
(607) P. Klass, "New AF gyro gets avionics assist," Aviation Wk., vol. 57, pp. 52-57; July 14,1952.

an attached arrow in accordance with the magnetic heading of the actual plane. Position should be indicated correctly to 0.4 mile in distance and approximately degree in azimuth. The maximum range is 115 miles, and the pilot changes charts at 20- to 30-minute intervals on the average. With a compact, simple, and up-to-date presentation of his situation constantly in view, the pilot may choose to follow the course by manual control, or may apply appropriate instructions and corrections to an automatic pilot.
(608) H. C. Hurley, S. R. Anderson, and H. F. Keary, "The Civil Aeronautics Administration VHF omnirange," PROC. I.R.E., vol. 39, pp. 1506-1520; December, 1951. IRE Abstract 1000.
(609) S. J. Davey, "The pictorial computer for air navigation," Military Engineer, vol. XLIV, pp. 274-276; July-August, 1952.

Omnibearing-Distance Program (OBD)
By international agreement several years ago, standards were established covering the design of ground facilities that are to provide azimuth and distance information suitable for guiding aircraft on overland flights.
With ground stations standardized and in an advanCed stage of installation, attention has shifted largely toward progressive refinement of the airborne instrumentation. It should be noted that the pilot is by no means limited to courses defined by straight lines between ground stations. Having continuous distance and bearing information referred to one or more known points on the ground, he may plot, with ruler and pen·cil, any suitable course on a map and may correct his heading and air speed at suitable intervals. From the start of the program, however, various automatic devices were designed and tested, all of them intended to minimize human participation in this routine navigational procedure, and thus to minimize errors and misinterpretations of data. Early versions were called offset-
course computers and were later referred to as courseline computers. The pilot could be given a left-right
indication with respect to an arbitrary course set up on the electronic computing machine, with progress indicated by conventional map-plotting techniques or by ·an ink line drawn automatically on co-ordinate paper.
Attention was directed toward the pictorial computer, which includes a 35-mm film-strip projector, essentially similar to aslide projector installed behind a 10-
inch translucent screen. One hundred feet of film accommodates as many as 700 navigation charts, each
centered at an OBD ground-station. Important areas may be represented by several different charts drawn to different map-scales. After the pilot selects an appropriate chart and adjusts the illumination level, the electronic apparatus takes over. Coded holes punched in the film tune the receiving set to the correct OBD station and match the scale of the computing mechanism to the scale of the chart. Two servomechanisms position a miniature airplane correctly on the projected image of the map. A third servo orients the miniature plane and

Decca Program
Decca is awell-known, intermediate-distance, hyperbolic navigation system, based on continuous recording of phase changes derivable from the programmed transmissions of four related ground stations. Such an array of stations, comprising amaster and three slaves, is called a "chain." A third Decca chain was recently activated in England, thus completing effective coverage of the British Isles and adjacent waters. In addition, the network now includes one Danish and one German chain. One French chain is under construction, while an Italian chain and one additional French chain reached the planning stage. About 1,100 British ships and 400 other ships have been equipped with Decca navigation instruments. Airborne Decca instrumentation now includes a pen that draws a line on moving co-ordinate paper to record the movements of the vehicle.
Overseas Navigation Program
The Loran system (hyperbolic co-ordinates, defined by differences in arrival-time of pulses from related pairs of stations) continues to be the chief source of overseas guidance for ships and planes. Here also there is atrend toward further mechanization of routine navigational procedures. The Sperry adapter, when connected to standard Loran receivers, provides a servomechanism for aligning the leading edges of received pulses. In comparison with manual alignment, accuracy and speed are improved.
Interest in the very-low-frequency range continues. Reference is made to acomprehensive report on longrange navigation instrumentation and to reports on radio-propagation studies intended to provide afactual basis for the design of any long-range navigation system.
Medium-distance navigation might some day exploit the new brute-force method of sending vhf signals reliably far beyond the optical horizon. This is wasteful of power, but perhaps not necessarily more so than vhf transmitters and antennas. Usable range, however, appears to be limited to the "single-hop" zone.
(610) B. Alexander, "Long-range-navigation instrumentation," Elec. Commun., vol. 29, pp. 9-11; March, 1952. IRE Abstract 1925.

480

PROCEEDINGS OF THE 1.R.E.

April

(611) A. T. Waterman, Jr., "Ray Theory Applied to a Spherical Ionosphere," and "Ionospheric Absorption of Obliquely Incident Radio Waves," Technical Reports No. 152 and 153, ONR Contract N5ori-07628 (to be published).
(612) J. A. Pierce, "Sky-Wave Field Intensity (I.) Low and Very Low Radio Frequencies," Technical Report No. 158, ONR Contract N5ori-07628 (to be published).
(613) "New Kind of VHF Propagation," Wireless World, vol. LVIII, pp. 273-274; July, 1952.
Countermeasures
Public attention was recently drawn to the Federal Communications Commission's control of electromagnetic radiation (CONELRAD) plan for stopping all normal broadcast transmission in the event of an airraid alert. Defense broadcasts will continue after all participating stations have switched to 640 or 1,240 kc, thereafter juggling all schedules and power outputs every few seconds, to confuse (by planned disorder) all enemy planes attempting to home on broadcast transmissions.
Vehicular Communications
There was an increase of about 15 per cent in the number of mobile units used in the land transportation, public safety, industrial, and common-carrier fields. Common-carrier mobile telephone service was extended to 160 cities serving over 12,000 mobile stations on 252 channels in the 30-50-mc and 152-162-mc bands. By the end of the year, atotal of 19 "crack" passenger trains, mainly in the eastern part of the United States, were equipped for mobile telephone service.
Field tests and measurements were initiated to compare 450, 900, and 3,700 mc with 150 mc for vehicular communications. These tests indicated abroad optimum of performance around 500 mc and that 450- and 900mc transmission is more favorable than 150 mc if full use can be made of antenna gain. Vehicular communications above 1,000 mc were not very satisfactory.
(614) W. R. Young, Jr. "Comparison of Mobile Radio Transmission at 150, 450, 9b0, and 3700 mc," presented I.R.E. Conference on Vehicular Communications, Washington, D. C.; December 3-5, 1952.
Equipments providing 20-kc channel spacing in the 152-162-mc band were made available by several manufacturers and provided satisfactory service.
(615) H. E. Strauss, "Channel-Space Consideration in 152-174 mc band," presented I.R.E. Conference on Vehicular Communications, Washington, D. C., December 3-5, 1952.
(616) N. H. Sheperd, "Report on Channel-Splitting Demonstration Conducted in Syracuse," presented I.R.E. Conference on Vehicular Communications, Washington, D. C.; December 3-5, 1952.
(617) D. E. Noble, "Commercial Experience with 160-mc, 20-kc equipment," presented I.R.E. Conference on Vehicular Communications, Washington, D. C.; December 3-5, 1952.
(618) C. F. Hobbs, "Techniques for close channel spacing at vhf and higher frequencies," PROC. I.R.E., vol. 40, pp. 329-333; March, 1952.
Increasing demand for additional channels resulted in several existing services moving into the 460-470-mc band. Some receiving equipment for this band employed automatic frequency control of the receiver oscillator.

Operations indicated less noise than at 150 mc and that the line-of-sight range was about the same in urban areas.
Feedback-Control Systems
Professional Growth
Each year of the past decade has seen increased professional interest in the field of feedback-control systems and an acceleration in the rate of appearance of significant technical contributions.
A new I.R.E. technical committee in this field was established in 1951 and is now preparing working standards.
Conferences
A number of important technical conferences of nation-wide scope were held. On December 6-7, 1951 a conference sponsored by the A.I.E.E. Committee on Feedback Control Systems was held at Atlantic City, N. J. The opening address discussed systems engineering as a new field that utilizes knowledge from many branches of engineering and science. The importance of training engineers to develop this systems approach was · stressed.
(619) G. S. Brown, and D. P. Campbell, "Control systems," Sci. Amer. vol. 187, no. 3, pp. 51-64; September, 1952.
This conference featured papers on the application of statistical concepts, the use of digital and analog data (to control machine processes), and the use of frequencyresponse techniques in the design of nonlinear and sampled-data control systems. Practical component problems were discussed, and one session was devoted to control systems utilizing human operators. None of the papers was published.
Another conference was held in Dallas, Texas, on March 10-11, 1952, sponsored by the A.I.E.E. In addition, technical sessions on feedback-control systems were included in the general meetings of the I.R.E., A.I.E.E., and A.S.M.E.
Books
In addition to revised editions of various well-known ' books, the following new books appeared:
(620) G. H. Farrington, "Fundamentals of Automatic Control," John Wiley and Sons, Inc., New York, N. Y.; 1951.
(621) A. Tustin (editor), "Automatic and Manual Control," Academic Press, Inc., New York, N. Y.; 1952.
(622) Selected Government Research Reports, "Servomechanisms," H. M. Stationery Office, London, England, vol. 5.
(623) A. E. Fitzgerald and C. Kingsley, Jr., "Electrical machinery," McGraw-Hill Book Co., Inc., New York, N. Y.; 1952.
Farrington's book is primarily of interest to processcontrol engineers. The next two books are actually collections of technical papers. Fitzgerald and Kingsley's book is not specifically directed toward the field of feedback control systems, but contains valuable introductory material in two chapters and detailed treatments and analyses of machinery used in feedbackcontrol systems.

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Radio Progress During 1952

481

Contribution to General Theory and Design Methods
New contributions to the design and analysis of linear feedback-control systems are represented by the following papers.
(624) J. R. Moore, "Combination open-cycle closed-cycle control systems," PROC. I.R.E., vol. 39, pp. 1421-1432; November, 1951.
(625) A. S. Baskenbom and R. Hood "Automatic Control Systems Satisfying Certain Criterions on Transient Behavior," NACA TN 2378,45 pp.; June, 1951.
(626) D. W. St. Clair, W. F. Coombs, Jr., and W. D. Owens, "Frequency response analysis for industrial automatic control systems," Trans. Amer. Soc. Mech. Engr., vol. 74, no. 7, pp. 1133-1155; October, 1952.
(627) A. A. Hauser, Jr., "A generalized method for analyzing servomechanisms," PROC. I.RE., vol. 40, pp. 197-202; February, 1952.
(628) 0. J. M. Smith, "Stabilization Templates for Servomechanisms," A.I.E.E. Tech. Paper 52-239; September, 1952.
(629) D. W. Russell, C. H. Weaver, "Synthesis of Closed Loop Systems Using Curvilinear Squares to Predict Root Location," A.I.E.E. Tech. Paper 52-82; December, 1951.
(630) Yuohan Chu, "Synthesis of Feedback Control Systems Using Phase-Angle Loci," A.I.E.E. Tech. Paper 52-297; September, 1952.
Nonlinear Systems
Emphasis was placed on nonlinear feedback control systems and particularly on the frequency-response techniques for analyzing and synthesizing such systems.
(631) J. Loeb, "Hereditary phenomena in servomechanisms; A general criterion of stability," Ann. Télécomm., vol. 6, pp. 346352; December, 1951.
(632) National Bureau of Standards "Translation of Papers on Stability of Non-Linear Feedback Control Systems," Nat. Bur. Stand. Report, No. 1691; 1952.
(633) E. C. Johnson, "Sinusoidal Analysis of Feedback Control Systems Containing Non-Linear Elements," A.I.E.E. Tech. Paper 52-154; April, 1952.
(634) C. Leondes, "A Study of Amplifier Saturation and Magnetic Saturation in a Servomechanism," A.I.E.E. Misc. Paper 52198; May, 1952.
Loeb's paper is a mathematical treatment and generalization of stability criteria applicable to both linear and nonlinear systems. The National Bureau of Standards report contains translations of earlier contributions by Goldfarb and Lichtman of the U.S.S.R. and by Oppelt of Germany. This recent translation makes previous contributions readily available in English. Johnson's paper extends the earlier work of others where the frequency-response approach is applied to nonlinear control systems. Leonde's paper cites aspecific example of this approach and includes numerical data.
Sampling Feedback-Control Systems
Another general problem in feedback-control system theory concerns the design and analysis of systems employing intermittent or sampled data. Significant advances are described in the following papers.
(635) W. K. Linvill, "Sampled Data Control Systems Studied through Comparison of Sampling with Amplitude Modulation," A.I.E.E. Tech. Paper 51-324.
(636) J. R. Ragazzini and L. A. Zadeh, "The Analysis of Sampled Data Systems," A.I.E.E. Tech. Paper 52-161; April, 1952.
(637) R. G. Brown and G. J. Murphy, "An Approximate Transfer Function for the Analysis and Design of Pulsed Servos," A.I.E.E. Tech. Paper 52-134; September, 1952.
(638) D. F. Lowden, "A general theory of sampling servo systems," Proc. I.E.E., pt. IV, vol. 98, pp. 31-36; October, 1951.

Human Operator and Human Problems
A notable recent advance was the use of feedbackcontrol system techniques of analysis in the study of human beings and human problems. In some of these studies, the subject of interest has been the action of a human being when he becomes part of afeedback-control system, as in aircraft tracking.
(639) L. S. Beals, Jr., "The human operator as alink in closed-loop control systems," Elec. Eng., vol. 71, pp. 319-324; April, 1952.
(640) C. E. Warren, P. M. Fitts, and J. R. Clark, "An Electronic Apparatus for the Study of the Human Operator in a OneDimensional Closed-Loop Continuous Pursuit Task," A.I.E.E. Tech. Paper 52-8; November, 1951.
Although these studies concern specific applications of human beings as servo elements, these and related investigations are expanding the knowledge of human physiology and the human nervous system. Feedbackcontrol theory is being applied to studies of human beings as individuals and as groups (mass dynamics). One very significant application to an important medical problem is described in the following paper.
(641) R. G. Bickford, "The use of feedback systems in the control of anesthesia," Elec. Eng., vol. 70, October, 1951.
Components
Among the papers describing new components and presenting advanced analyses of existing components are
(642) R. H. Frazier, "Analysis of the Drag-Cup A-C Tachometer," A.I.E.E. Tech. Paper 51-348.
(643) C. C. Johnson, »A homopolar tachometer for servomechanisms, PROC. I.R.E., vol. 40, pp. 158-160; February, 1952.
(644) Shih-Ying Lee and J. F. Blackburn, "Contributions to hydraulic controls," Trans. Amer. Soc. Mech. Eng., vol. 74, no. 6, pp. 1005-1016; August, 1952.
All these papers present studies of control components that are of frequent interest to designers. The paper by Lee and Blackburn presents some data and concepts concerning hydraulic-control components and helps answer anumber of questions that are frequently raised by control engineers.
Applications
The published literature described only asmall proportion of the many new applications of feedbackcontrol system theory.
(645) R. N. Bretoi, "Automatic flight control--analysis and synthesis of lateral control problem," Trans. Amer. Soc. Mech. Eng., vol. 74, no. 3; April, 1952.
(646) M. Cambernac and F. Lajeunesse, "Stabilization of direct current servomechanisms," Onde Elec., vol. 31, pp. 434-445; November, 1951.
(647) G. Klein, "Analysis and construction of aposition fixing servomechanism,» Ann. Télécomm., vol. 6, pp. 313-324; November, 1951.
(648) W. M. Pease, "An automatic machine tool," Sci. Amer., vol. 187, pp. 101-115; September, 1952.
The last reference described an application of electronic control and servomechanism techniques that represents asignificant advance in the automatic control of machine processes. The prototype machine, which is now in operation to establish the feasibility of this

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PROCEEDINGS OF THE I.R.E.

April

method, is shown in the picture below. This machine, developed at the Servomechanisms Laboratory of the Massachusetts Institute of Technology and sponsored by the U. S. Air Force, utilizes digital data, stored on punched tapes, to prescribe machine operation.

Circuits
Linear Active Networks
The fundamental principles of feedback continued to be subjected to analysis as marginal obscurities were examined and occasionally clarified. General methods of analysis still received attention. Further progress on an approach that examines the paths of migration of the poles and zeroes of relevant functions as certain parameters are varied provides a penetrating insight into the performance of afeedback system.

Fig.10--Feedback control systems machine, developed at the Servomechanisms Laboratory of the Massachusetts Institute of Technology and sponsored by the U. S. Air Force, utilizes digital data, stored on punch tapes, to prescribe machine operation.
Terminology
Two professional society subcommittees have been cooperating to establish aconsistent system of nomenclature and symbolism for use in this field. The results to date have been reported in the following papers
(649) Committee on Terminology of Industrial Instruments and Regulators, Amer. Soc. Mech. Eng. "Automatic control terminology," Mech. Eng., vol. 74, pp. 486-489; June, 1952.
(650) Feedback Control Systems Committee, A.I.E.E. "Proposed symbols and terms for feedback control systems," Elec. Eng., vol. 70, pp. 905-909; October, 1951.
A subcommittee of the I.R.E. Technical Committee on Feedback Control Systems is now active in the development of a system of terminology that will reflect adequately the current usage in the field of feedback controls and that is compatible with other fields of interest within the I.R.E.
Supporting Fields
Many of the developments stemmed from work done in other fields.
The role of electronic analog computers is particularly significant, especially in the study of nonlinear control systems where direct analytic techniques are unduly cumbersome.
Public Recognition
The Scientific American for September, 1952 emphasized to the lay public the importance of this professional field. That issue was devoted exclusively to articles on feedback-control systems by leading workers. Although written for anontechnical reader, it is recommended to engineers and scientists as well.

Linear-Varying Parameter and Nonlinear Circuits
Developments were concerned mainly with specific problems and are covered under the appropriate fields of application, such as information theory and modulation systems and electronic computers. General theoretical work continued on operational and integral transform methods of solving linear time-varying systems.
(651) J. A. Aseltine and D. L. Trautman, "Transforms for linear time-varying network functions," presented I.R.E. National Convention New York, N. Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 226; February, 1952.
(652) L. A. Zadeh, "Operational analysis of variable-delay systems," PROC. I.R.E., vol. 40, pp. 564-568; May, 1952.
Transistor Circuitry
Semiconductor devices are in a stage of very rapid change and development, and it follows that transistor circuitry is itself in a rapidly changing state. This is true with particular regard to the upper limits of performance. Transistors have been viewed as low-power devices, but within the year Hall reported a transistor capable of 100-watts output. Upper-frequency limit has been raised by orders of magnitude with the announcement of atransistor television set and ajunction tetrode that oscillates in the 100-mc region.
Transistor circuitry can be divided into two areas:
the large-signal application in pulse devices, largely computers at the present, and the small-signal application in which linear amplification is of primary importance.
The small size and low power requirements of the transistors are primary advantages in computers requiring large numbers of elements. The types of circuit most generally used have been astable, monostable, or bistable negative resistances employing a singlepointcontact transistor and, frequently, semiconductor diodes to improve the characteristics of the circuits. In this field the work of Felker is significant. In his circuits all amplification was derived from regenerative pulse amplifiers that, during each period of the clocking device, regenerate pulses and essentially supply new energy to replace that lost in the preceding period. Memory devices consist of these regenerative amplifiers and delay lines which restore and continually circulate the stored bits. This technique was employed earlier with vacuum tubes in the SEAC machine.
(653) J. H. Felker, "Regenerative amplifier for digital computer applications," PROC. I.R.E., vol. 40, pp. 1584-1596; November, 1932.

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Radio Progress During 1952

483

A number of papers describe and analyze basic negative-resistance switching circuits using point-contact transistors.
(654) B. G. Farley, "Dynamics of transistor negative-resistance circuits,» PROC. I.R.E., vol. 40, pp. 1497-1508; November, 1952.
(655) A. W. Lo, "Transistor trigger circuits,» PROC. I.R.E., vol. 40, pp. 1531-1541; November, 1952.
(656) A. E. Anderson, "Transistors in switching circuits,» PROC. I.R.E., vol. 40, pp. 1541-1558; November, 1952.
(657) L. P. Hunter and H. Fleisher, "Graphical analysis of some transistor switching circuits," PROC. I.R.E., vol. 40, pp. 15591562; November, 1952.
(658) G. E. McDuffie, Jr., "Pulse duration and repetition rate of a transistor multivibrator," PROC. I.R.E., vol. 40, pp. 14871489; November, 1952.
The use of diode matrices to perform switching functions in a computer may involve a large number of diodes that are in parallel and the back current of even good point-contact diodes imposes a limitation on performance. New silicon-junction diodes are remarkably better in this respect, possessing reverse currents that may be as low as 10-l° ampere, which, coupled with their rectification ratios of 10 8,makes them ideally suited to the matrix application.
(659) G. L. Pearson and B. Sawyer, "Silicon p-n junction alloy diodes," PROC. I.R.E., vol. 40, pp. 1348-1351; November, 1952.
Transistor circuits that perform a number of special computing functions were reported.
(660) R. L. Trent, "A transistor reversible binary counter," PROC. I.R.E., vol. 40, pp. 1562-1572; November, 1952.
(661) R. L. Trent, "Two transistor binary counter," Electronics, vol. 25, pp. 100-101; July, 1952.
(662) J. R. Harris, "A transitor shift register and serial adder," PROC. I.R.E., vol. 40, pp. 1597-1602; November, 1952.
Point-contact transistors in combination with junction photocells were used to locate to 0.001 inch and record in binary form the motions of amovable element.
(663) H. G. Follingstad, J. N. Shive, and R. E. Yeager, "An optical position encoder and digit register," PROC. I.R.E., vol. 40, pp. 1573-1583; November, 1952.
Junction transistors are ordinarily considered superior to those of the point-contact variety in linear or small-signal application because of their greater uniformity of characteristics and better noise properties. The better high-frequency characteristics of the pointcontact transistor has been largely overcome with the invention of the junction-transistor tetrode by Wallace. It was reported that junction tetrodes are very effective in video and IF amplifiers and in oscillators in the 10mc range.
(664) R. L. Wallace, Jr., L. G. Schimpf, and E. Dickten, "A junction transistor tetrode for high-frequency use," PROC. I.R.E., vol. 40, pp. 1395-1400; November, 1952.
On the other hand, point-contact transistors made of suitable material with proper point spacing were applied satisfactorily in high-frequency linear amplifiers and sine-wave oscillators.
(665) B. N. Slade, "The control of frequency response and stability of point-contact transistors," PROC. I.R.E., vol. 40, pp. 13821384; November, 1952.
(666) G. M. Rose and B. N. Slade, "Transistors operate at 300 mc," Electronics, vol. 25, pp. 116-118; November, 1952.
The first applications of medium and high-power transistors were described and included a 100-watt amplifier reported by Hall.

(667) C. L. Rouault and G. N. Hall, "A high-voltage, medium-power rectifier," PROC. I.R.E., vol. 40, pp. 1519-1521; November, 1952.
(668) R. N. Hall, "Power rectifiers and transistors," PROC. I.R.E., vol. 40, pp. 1512-1518; November, 1952.
(669) R. F. Shea, "Transistor power amplifier," Electronics, vol. 25, pp. 106-108; September, 1952.
A number of papers described point-contact and junction transistors in amplifiers and oscillators that would ordinarily use vacuum tubes. The substitution of transistors for vacuum tubes can be made through the duality principle for point-contact transistors and directly for junction units.
(670) L. J. Giacoletto, "Junction transistor equivalent circuits and vacuum tube analogy," PROC. I.R.E., vol. 40, pp. 1490-1493; November, 1952.
However, distinctions between the two devices exist and the circuit analogy for junction transistor applications, as the case with duality for the point-contact type, must be suggestive rather than exact. Transit-time effects in junction transistors were found to be significant at frequencies just above the audio-frequency band for some connections, and this complication must be considered.
(671) R. L. Pritchard, "Frequency variations of current-amplification factor for junction transistors," PROC. I.R.E., vol. 40, pp. 1476-1481; November, 1952.
(672) D. E. Thomas, "Transistor amplifier-cutoff frequency," PROC. I.R.E., vol. 40, pp. 1481-1483; November, 1952.
Information Theory and Modulation Systems
The trend established in recent years continued. Most of the work has been based on information theory concepts rather than on conventional modulationsystem approaches.
There has been considerable probing into the basic concepts of information theory, such as information itself, its definition, measurement, and relation to the thermodynamic concept of entropy. It was shown, for example, that even with the advent of micropower transistors the circuit power levels are still many orders of magnitude greater than basically required for accommodating reasonable information rates.
(673) E. Reich, "On the definition of information,» Jour. Math. Phys., vol. 30, pp. 156-161; October, 1951.
(674) D. A. Bell, "Physical entropy and information," Jour. Appl. Phys., vol. 23, pp. 372-373; March, 1952.
(675) J. H. Felker, "A link between information and energy," PROC. I.R.E., vol. 40, pp. 728-729; June, 1952.
Shannon's theory of communication has continued to arouse agreat deal of interest as evidenced by numerous articles discussing the basic concepts of information theory. The results of the theory have been reobtained by reasoning from somewhat different viewpoints. In some cases, particular aspects implicit in the theory have been examined in detail, such as the delay time needed to approach the ideal channel capacity in a practical case.
Other papers attempted to present apicture of the history and status of information theory, in some cases with aslant toward some particular branch of the communication field.

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PROCEEDINGS OF THE I.R.E.

April

(676) P.M .Woodward and I.L. Davies, "Information theory and inverse probability in telecommunication," Proc. I.E.E. (London), vol. 99, pt. 3, pp. 37-44; March, 1952.
(677) K.Küpfmüller, "Channel capacity and transmission time," Arch. Etch. überlragung, vol. 6, pp. 265-268; July, 1952.
(678) W .Weaver, G. E. Peterson, and H. Davis, "Information theory," Jour. Speech and Hearing Disorders, vol. 17, pp. 166197; June, 1952.
(679) W .Meyer-Eppler, "Information theory," Nalurwiss, vol. 39, no. 15, pp. 341-347; August, 1952.
Much interest was centered around practical applications of information theory. It was shown that there are inherent difficulties in approaching the theoretical maximum rate of information transmission. Drastic attempts to approach the ideal lead to excessive complication of apparatus.
(680) W .R. Bennett, "Practical significance of information theory in transmission problems," presented I.R.E. Western Convention, Long Beach, Calif.; August 26-29, 1952.

(683) D. A. Huffman, "A method for the construction of minimum redundancy codes," PROC. I.R.E., vol. 40, pp. 1098-1101; September, 1952.
With a view towards determining how closely the ideal channel capacity can be approached, alarge number of different codes have been examined, for both discrete and continuous channels. Surprisingly, all the good codes fall short of the ideal by approximately equal amounts; a signal-to-noise ratio of the order of 8 db higher than ideal is required to attain a given transmission rate. Highly complicated codes are presumed to be necessary for signaling at rates near the actual channel capacity.
(684) E. N. Gilbert, "A comparison of signaling alphabets,» Bell Sys. Tech. Jour., vol. 31, pp. 504-522; May, 1952.
The problem of optimum separation of signal and

noise has continued to receive agreat deal of attention

from the information-theory viewpoint. A number of

papers on this subject (as well as other subjects dis-

cussed below) were presented at the Symposium on Ap-

plications of Communication Theory, held in London,

September 22-26, 1952. The proceedings of this sym-

posium including the papers and aportion of the discus-

sion will be issued in book form by the Butterworth

press.

It was shown formally how existing means for op-

timum separation of a signal from white noise can be

applied to other statistical types of noise, and further-

more, how areceiver can recover the most information

from incoming symbols by utilizing their a posteriori

probability distribution.

Various approaches to the problem of optimum filter-

ing of noisy signals appeared in the literature. A few

were based on the Wiener-Lee criterion, and some were

Fig. 11--Dr. Claude E.Shannon, Bell Telephone Laboratories mathematician, sets his electrical mouse down in amaze through which it will thread its way to adistant "piece of cheese" (an electrical terminal) in 12 to 15 seconds. The mouse uses for its "brain" some of the same kind of switching relays found in dial telephone systems. It was designed to provide fundamental knowledge which will help improve telephone service.
Coding is one of the processes essential to most practical applications of information theory. A number of significant contributions were made in this field. The so-called Shannon-Fano code uses short groups of symbols to designate highly probable events and proportionately long groups for improbable events, thereby minimizing the average number of symbols per event. With certain probability distributions this code may actually be optimum, but it is only near-optimum in

based on different viewpoints, for example, on the principle of inverse probability, on the concept of existence probability, on arather general criterion of anonprobabilistic type, or on achoice of various statistical criteria.
(685) R. M. Fano, "Communication in the presence of additive Gaussian noise," presented Symposium on Application of Communication Theory, London; September 22-26, 1952.
(686) P. M. Woodward, "Information theory and the design of radar receivers," PROC. I.R.E., vol. 39, pp. 1521-1524; December, 1951.
(687) I.L. Davies, "On Determining the presence of signals in noise," Proc. I.E.E.(London), vol. 99, pt. 3, pp. 45-51; March, 1952.
(688) L. A. Zadeh and J. R. Ragazzini, "Optimum filters for the detection of signals in noise," Paoc. I.R.E., vol. 40, pp. 12231231; October, 1952.
(689) D. Middleton, "Statistical methods for the detection of pulsed radar in noise," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.

general. A new procedure has now been devised by which the optimum code can be constructed for any probability distribution of the events to be coded.
Practical methods were described by which successive samples of asignal can be made more nearly independent so that they can be efficiently coded by using a Shannon-Fano code.
(681) B. M .Oliver, "Efficient coding," Bell Sys. Tech. Jour., vol. 31, pp. 724-750; July, 1952.
(682) P. Elias, "Predictive coding," presented I.R.E. National Convention, New York, N. Y.; March 3-6, 1952.

A number of papers dealt with the technique of radar detection whereby successive sweeps are stored and superposed. In one instance, superposition of 22 sweeps showed an impressive rise in signal-to-noise ratio. Detection methods based on correlation techniques, likewise introduced in recent years, were discussed to a lesser extent.
(690) P.L. Waters, "Video signal integration using astorage tube," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.

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Radio Progress During 1952

485

(691) J. Icole and J. Oudin, "Time analysis and filtering," Ann. Telecomm., vol. 7, pp. 99-108; February, 1952.
The construction of apparatus for measuring auto-
correlation and cross correlation continued to receive attention.
A new electronic analog correlator was constructed at Massachusetts Institute of Technology with the object of evaluating and displaying simultaneously several (five) pointed of the correlation curve. Such acorrelator enables one to watch the correlation curve change, while the statistics of the signal vary, e.g., in music. The operation of this general-purpose correlator is largely based on pulse techniques which allows agreat deal of flexibility.
Correlators for more specific applications were also built. Use was made of magnetic tape or magnetic drums to obtain the required delay. In some cases, correlation techniques were applied to problems outside the field of communications.
(692) M. J. Levin and J. P. Reintjes, "A five-channel electronic analog correlator," presented National Eelectronic Conference, Chicago, III.; September 29-October I, 1952.
(693) F. E. Brooks, Jr. and H. W. Smith, "A computer for correlation functions," Rev. Sci. Instr., vol. 23, pp. 121-126; March, 1952.
(694) R. A. Johnson and D. Middleton, "Measurements of autoand cross-correlation functions of modulated carriers and noise following a non-linear device," presented Symposium on Applications of Communication Theory, London; September 2226, 1952.
(695) V. J. Guethlein, "Correlator for low frequencies," presented I.R.E. National Convention, New York, N. Y.; March 3-6, 1952.
Measurements of correlation were made also in the application of information theory to television. Autocorrelation curves and contours of constant autocorrelation were determined for typical pictures by simple optical means. Likewise by optical means, probability distributions of the amplitudes, as well as of the amplitude changes (between adjacent picture elements) were obtained. Such statistical data furnishes an estimate of the minimum redundancy removable by simple, linear means and, hence, an estimate of the theoretically possible bandwidth reduction. The power-density spectrum of the video signal was analyzed using autocorrelation theory, and the effect of statical parameters of motion and complexity on the spectrum was studied.
Experimental work was described in which much of the linear correlation was actually removed from television signals. This was done by predicting future signal values on the basis of past values and then transmitting only the difference between the actual and the predicted signal. Since the prediction is based on alinear, weighted summation of past values, it is referred to as linear prediction. The success of such a prediction criterion is closely allied with the autocorrelation of the signal and is readily appraised by measuring the relative mean power or the amplitude distribution of the "reduced" signal.
Work was reported also on the information-theory aspects of describing simple line drawings by methods more efficient than the conventional television scan. Also, an elaborate analysis was made of the possible

savings obtainable from the technique of variable-rate scanning, by which the picture detail is more uniformly distributed over the video signal. This analysis involves aquantitative measure of picture detail, which was experimentally determined for a number of typical pictures.
(696) E. R. Kretzmer, "Statistics of the television signals," Bell Sys. Tech. Jour., vol. 31, pp. 751-763; July, 1952.
(697) M. B. Ritterman, "An application of auto-correlation theory to the video signal of television," Sylv. Tech., vol. 5, pp. 70-75; July, 1952.
(698) C. W. Harrison, "Experiments with linear prediction in television," Bell Sys. Tech. Jour., vol. 31, pp. 764-783; July, 1952.
(699) J. Loeb, "Communication theory of transmission of simple drawings," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
(700) E. C. Cherry and G. G. Gouriet, "Some possibilities for the compression of television signals by recoding," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
A great deal of work was reported in the field of speech, some of it barely falling within the realm of information theory but nevertheless of great interest to workers in the field.
More was learned about the identification of subjective sounds from the characteristics of the acoustic wave; identification of vowel sounds was found to be possible from the position of peaks in the spectral distribution.
A machine was constructed which recognizes, selects, and codes spoken words. The codes are then interpreted by appropriate circuits, so that no human perception is involved in the actual recognition.
The reverse process has also been instrumented in admirable fashion. Experimental apparatus has been constructed in England which makes possible the synthesis of speech from slowly varying parameters. These parameters specify the resonant frequencies of the vocal cavity system and the excitation applied to it. The synthesized speech has good intelligibility and the information content of the controlling signals is estimated to be less than one fiftieth of that of normal telephone speech signals. The input control signal consists of 150 samples per second. A second speech synthesizer was built for the United States Air Force. This equipment accepts an input telegraphic code from which it constructs speech by selecting the appropriate basic speech sounds and patching them together.
(701) G. E. Peterson, "Information bearing elements of speech," presented Symposium on Application of Communication Theory, London; September 22-26, 1952.
(702) K. H. Davis, R. Biddulph, and S. Balashek, "Automatic recognition of spoken words," presented Symposium on Application of Communication Theory, London; September 2226, 1952.
(703) W. Lawrence, "The synthesis of speech from slowly varying parameters," presented Symposium on Application of Communication Theory, London; September 22-26, 1952.
(704) W. G. Tuner and H. H. Williams, "A speech synthesizer," presented Symposium on Application of Communication Theory, London; September 22-26, 1952.
A new theory of hearing was presented; it postulates asimple mechanism whereby vibrations traveling down the cochlear partition can create two distinct waves of neural stimulation. The theory makes it possible to explain some significant experimental data not hitherto understood.

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PROCEEDINGS OF THE I.R.E.

April

Aimed at establishing a link between information theory, the structure of language, and, ultimately, the properties of the brain, a theory of language structure was developed. Some of the results are similar to those of Zipf, but appear to go asignificant step further.
Another provocative theory which was presented during the past year is that of semantic information. In contrast to the existing statistical theory of information, this new theory decisively involves the contents of the symbols instead of merely their frequencies of occurrence. It was indicated that the statistical theory can be mapped on to the theory of semantic information, that the latter sheds new light on parts of the former, and that the semantic concept of information may ultimately lead to a better psychological concept of information than the present statistical concept.
(705) W. H. Huggins, "A theory of hearing," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
(706) B. Mandelbrot, "An informational theory of the structure of language based upon the theory of statistical matching of message and coding." presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
(707) Y. Bar-Hillel and R. Carnap, "Semantic information," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
Such basic topics as noise, power spectra, sampling, quantization, and companding also received their share of attention.
The spectral distribution of energy in noise and signal-modulated waves was analyzed for amplitude and angle modulation. A general analysis was made of the relations between input and output signal-to-noise power ratios in band-pass limiters. New techniques of noise analysis were described and some experimental observations on random noise were also reported.
The concept of an instantaneous power spectrum was discussed and defined mathematically. It is dependent not only on the present hut also on the past history of the signal.
The sampling theorem is clear cut since it implies an ideal filter. An analysis was made of the less clear-cut situation of a nonideal low-pass filter, with the object of determining the effect of cut-off shaping and sampling frequency.
Quantization distortion, such as that experienced in pulse-code modulation, was again subjected to theoretical treatments. One of these analyses was rather general.
The practically important technique of speech cornpanding was subjected to a thorough analysis. It was found that if compressed speech is to be transmitted without distortion over the same restricted band adequate for uncompressed speech the transmission system is subject to more severe attenuation and phase-shift requirements.
(708) D. Middleton, "On the distribution of energy in noise- and signal-modulated waves," Quart. Appl. Math., vol. 9, pp. 337354; January, 1952; vol. 10, pp. 35-56; April, 1952.
(709) W. B. Davenport, "Signal-to-noise ratios in band-pass limiters," Technical Report 234; Research Laboratory of Electronics, M.I.T., Cambridge, Mass.; May 29, 1952.

(710) R. C. Davis, "New techniques in the mathematical analysis of noise," presented I.R.E. Western Convention, Long Beach, Calif.; August 26-29, 1952.
(711) V. J. Francis, "Random noise. Rate of occurrence of peaks," Wireless Eng., vol. 29, pp. 37-40; February, 1952.
(712) C. H. Page, "Instantaneous power spectra," Jour. Ape Phys.,
vol. 23, pp. 103-106; January, 1952. (713) J. W. Haanstra, "Sampling and recovery of continuous in-
formation," presented I.R.E. Western Convention, Long Beach, Calif.; August 26-29, 1952. (714) J. P. Schouten and H. W. F. van't Groenewout, "Analysis of
distortion in pulse-rode modulation systems," Appl. Sci. Res.,
sec. B, vol. 2, no. 4, pp. 277-290; 1952. (715) J. C. Lozier, "Instantaneous compandors on narrow-band
speech channels," Bell Sys. Tech. Jour., vol. 30, pp. 1214-1220; October, 1951.
During the period immediately following World War II the technical literature abounded with analyses aimed at evaluating the relative merits of the numerous modulation systems, particularly pulse systems. The advent of information theory has, of course, changed the complexion of this problem by making it possible to compare actual system performance to an absolute ideal performance. During the past year several authors compared the various systems from the viewpoint of information theory.
A new theoretical approach to linear multiplexing, making use of geometrical signal representation, was described in detail. Also on the subject of multiplex systems, comparisons were made, as in past years, between time and frequency sharing, and analyses were made of distortion and of cross talk in time-division multiplex systems.
(716) Z. Jelonek, "A comparison of transmission systems," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
(717) S. Goldman, "Information theory of noise reduction in various modulation systems," presented Symposium on Applications of Communication Theory, London; September 22-26, 1952.
(718) L. A. Zadeh and K. S. Miller, "Fundamental aspects of linear multiplexing," Pnoc. I.R.E., vol. 40, pp. 1091-1097; September, 1952.
(719) L. J. Libois, "Use of pulse modulation for transmission in a group of telephony channels of carrier-current systems," Onde Elec., vol. 32, pp. 190-196; April/May, 1952.
A number of new ideas in modulation and multiplexing were revealed during the past year. A new type of "one-unit" pulse code modulation, requiring only very simple terminal apparatus, has been developed. In this so-called system of delta modulation, changes in the signal are transmitted periodically, instead of the signal itself, by comparing the signal to asampled quantized approximation of itself. If, at the instant of sampling, the signal value exceeds the quantized value, apulse of fixed amplitude is sent; if not, no pulse is sent. The comparison is effected by afeedback circuit that is closed only at the sampling times. The sampling rate is made suf. ficiently high so that the staircase approximation of the signal reobtained at the receiver is adequate, e.g., 100 kc for speech. This makes efficient use of the bandwidth required and has the virtue of simplicity.
A class of modulation systems referred to as ambiguous-index systems was proposed, with the object of devising new systems which avoid certain defectiof existing ones.

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Radio Progress During 1952

487

Nonsynchronous time division, anew system of multiplexing made possible by sampling randomly instead of sampling periodically, was built and tested. The samples derived from the signals of the various channels are coded into different characteristic pulse groups so that the receiver can identify each sample as belonging to a certain channel. Occasional coincidence of the randomly spaced pulse groups causes some noise, which increases with the number of channels; but on the other hand, the system has unusual flexibility. As more channels are used, no well-defined point of overload is ever reached, although the quality deteriorates.
(720) L. J. Libois, "A new method of code modulation: 'a-modulation'," Onde Elec., vol. 32, pp. 26-31; January, 1952.
(721) J. F. Schouten, F. De Jager, and J. A. Greefkes, "Delta modulation, a new modulation system for telecommunication," Philips Tech. Rev., vol. 13, pp. 237-245; March, 1952.
(722) C. W. Earp, "A recent development in communication technique," Proc. I.E.E. (London), vol. 99, pt. 3, pp. 181-186; July, 1952.
(723) J. R. Pierce and A. L. Hopper, "Nonsynchronous time division with holding and with random sampling," PROC. I.R.E., vol. 40, pp. 1079-1088; September, 1952.
The British Broadcasting Company, after aseries of tests, has planned a frequency-modulation service for the United Kingdom. As opposed to amplitude modulation, frequency modulation was found to give approximately twice the range for the same quality of service.
Also in the field of frequency modulation, it was shown that a receiver can be made more nearly ideal (with regard to rejecting an interfering signal that is only slightly weaker than the wanted signal) by using feedback across the limiter. Furthermore, there appeared adetailed analysis of acommonly used but little understood component of frequency-modulation receivers, namely, the ratio detector.
(724) "The B.B.C. scheme for V.H.F. broadcasting," BBC Quart., vol. 6, pp. 171-181; Autumn, 1951.
(725) R. M. Wilmotte, "Reduction of interference in F.M. receiver and feedback across the limiter," PROC. I.R.E., vol. 40, pp. 34-36; January, 1952.
(726) B. D. Loughlin, "The theory of amplitude-modulation rejection in the ratio detector," PROC. I.R.E., vol. 40, pp. 289-296; March, 1952.

(728) F. M. Greene, "Calibration of commercial radio field-strength meters at the National Bureau of Standards," N.B.S. Cir. 517; December, 1951.
(729) M. C. Selby, "Accurate rf microvolts," (paper delivered at the 1952 IRE National Convention), PROC. I.R.E., vol. 40, p. 218; February, 1952.
(730) F. L. Hermach, "Thermal converters as ac-dc transfer standards for current and voltage measurements at audio frequencies," Jour. Res. Nat. Bur. Stand, vol. 48, pp. 121-128; February, 1952.
(731) A. L. Cullen, "Absolute power measurement at microwave frequencies," Prot. IEE (London), vol. 99, pp. 100-111; April, 1952
(732) A. L. Cullen, "A general method for the absolute measurement of microwave power," Prot. IEE (London), vol. 99, pp. 112120; April, 1952.
(733) L. R. M. Vos de Wael, "Direct reading frequency measuring equipment for the range of 30 c/s to 30 Mc/s," PROC. I.R.E., vol. 40, pp. 807-813; July, 1952.
(734) F. K. Harris, "Electrical Measurements," John Wiley and Sons, Inc., New York, N. Y., 1st ed.; 1952.
(735) D. D. King, "Measurements at Centimeter Wavelength," D. Van Nostrand Co., Inc., New York, N. Y., 1st ed.; 1952.
(736) A. W. Warner, "High-frequency crystal units for primary frequency standards," PRoc. I.R.E., vol. 40, pp. 1030-1033; September, 1952.
(737) V. H. Atree, "Precision voltage source," Wireless Eng., vol. 29, pp. 226-230; September, 1952.
(738) V. J. Tyler, "A simple bolometer for dissipation measurements," Marconi Rev., vol. 15, pp. 114-117; 3rd quart., 1952.
(739) H. T. Wilhelm, "Impedance bridges for the megacycle range," Bell Sys. Tech. Jour., vol. 31, pp. 999-1012; September, 1952.
(740) C. C. Cook, "Calibration of commercial field-strength meters," Tele-Tech, vol. 11, pp. 44-46,96,99-101; October, 1952.
(741) H. W. Kline, "Industrial frequency standard," Electronics, vol. 25, pp. 130-131; November, 1952.

Instrumentation
Basic Standards and Calibration Methods
A new basic unit of time (the sidereal year), supplementing and less variable than mean solar time, was adopted by the International Astronomical Union. Time reckoned in the new unit will be designated "ephemeris time." The application of atomic frequency and time standards as well as high-precision, high-frequency quartz crystal oscillators appeared most promising.
The closest approach to a basic standard was announced for accurate voltages of the order of microvolts and millivolts at all frequencies up to about 1,000 mc. This standard was arelatively inexpensive reliable constant-voltage source with its output independent of frequency. It seems to satisfy a crying need of many years standing.
(727) H. H. Ski(ling, "Electric Transmission Lines," McGraw-Hill Book Co., Inc., New York, N. Y., 1st ed.; 1951.

Fig. 12--"The Finger," more technically known as an ion chamber, is far smaller than other gamma-ray detectors of the same type and sensitivity which are used to detect deadly atomic rays in planes flying over A-bomb blast sites. This device was developed and built by the General Electric Company's Tube Department.
Audio-Frequency Measurements
Precision magnetic-tape recorders are being used extensively in audio-frequency measurements, particularly for acoustic noise problems. These recorders provide apermanent record of the signal, they can be used as an accessory for spectrum analysis of signals of short duration, and they aid in subjective comparisons of various types of signals. Binaural recording on magnetic tape appears to be particularly useful for this subjective comparison. One method of magnetic recording, called boundary-displacement recording, has been developed primarily for instrumentation purposes. It makes the visual display of the recorded magnetic signal possible.

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PROCEEDINGS OF THE I.R.E.

April

(742) H. L. Daniels, "Boundary-displacement magnetic recording," Electronics, vol. 25, pp. 116-120; April, 1952.
Some new instruments for the measurement of power, voltage, and phase at audio frequencies were described.
(743) D. E. Garrett and F. G. Cole, "A general-purpose electronic wattmeter," PROC. I.R.E., vol. 40, pp. 165-171; February, 1952.
(744) L. A. Rosenthal and G. M. Badoyannis, "Mean square vacuum-tube voltmeter," Electronics, vol. 25, pp. 128-131; September, 1952.
(745) H. W. Curtis, "Measuring the mean power of varying-amplitude complex audio waves," PROC. I.R.E., vol. 40, pp. 775779; July, 1952.
(746) G. N. Patchett, "A versatile phase-angle meter," Electronic Eng. (London), vol. 24, pp. 224-229; May, 1952.
(747) J. C. West, "A simple variable frequency phase measuring device," Electronic Eng. (London), vol. 24, pp. 402-403; September, 1952.
The work of the National Bureau of Standards in developing highly accurate methods for transferring ac current and voltage measurements to dc measurements was reported. An accuracy of 0.01 per cent in the frequency range from 25 to 20,000 cycles per second was indicated. In this development, several factors that limit the transfer accuracy of thermal converters were discovered.
(748) F. L. Hermach, "Thermal converters as ac-dc transfer standards for current and voltage measurements at audio frequencies," Jour. Res. Nat. Bur. Stand., vol. 48, pp. 121-138; February, 1952.
A number of different methods are used for measuring the nonlinear distortion in audio systems. The results of such measurements, however, are not readily interpreted in terms of the distortion that can be noticed by the listener because the available psychological data are not adequate for this purpose. Two investigations recently completed supply some of this needed information. In one set of experiments asignal of two tones at an interval of a perfect fifth was compared before and after transmission through a nonlinear network. When the mean frequency of the interval was above 1kc and the sound-pressure level was above 50 db (with respect to 0.0002 microbar), distortions greater than about onehalf per cent were noticeable. For lower frequencies and lower levels, the minimum detectable distortion was, in general, appreciably higher. Further experiments also showed that nonlinear distortion made small errors of intonation more noticeable.
In the second set of experiments, the just-perceptible modulation of one tone by another was measured, an extension of work done by others. The results showed that the sensitivity to modulation increased with increasing level, and the sensitivity to amplitude modulation was aminimum for modulating frequencies in the range from 20 to 100 cps. The just-perceptible amplitude modulation in this range was about 3 per cent at an 80-db sound-pressure level. When the frequency of the modulated component was above 1kc, the maximum sensitivity was observed for modulating frequencies between about one-fifth and two-thirds of the frequency of the modulated component. For this range of frequencies, at an 80-db sound-pressure level, an amplitude modulation of less than one-fifth of one per cent could be detected.

(749) R. Feldtkeller, "Die Heerbarkeit nichtlinearer Verzerrungen bei der Vbertragung musikalischer Zweiklânge," Akust. Beihefte, no. 3, pp. 117-124; 1952.
(750) E. Zwicker, "Die Grenzen der Hiferbarkeit der Amplitudenmodulation und der Frequenz modulation emes Tones," Akus. Beihefte, no. 3, pp. 125-133; 1952.
The tone-burst technique is being more generally used for audio-frequency measurements. A tone-burst is asinusoidal oscillation that is turned on for anumber of cycles and then turned on. In one measurement technique, the energy that remains in the system after the applied oscillation is turned off is used as ameasure of the transient distortion. In another application the measurement is made during the time the oscillation is on in order to avoid the effects of reflected signals. A tone-burst technique was also used as one method of evaluating the acoustic properties of rooms.
(751) M. C. Kidd, "Tone-burst generator checks a-f transients," Electronics, vol. 25, pp. 132-135; July, 1952.
(752) R. L. Terry and R. B. Watson, "Pulse techniques for the reciprocity calibration of microphones," Jour. Acous. Soc. Amer., vol. 23, pp. 684-685; November, 1951.
(753) T. Somerville and C. L. S. Gilford, "BBC pulsed-glide displays," FM-TV, vol. 12, pp. 22f, 43; June, 1952; and pp. 28, 30; July, 1952.
High-Frequency Measurements
Three books that devoted at least a large part of their space to high-frequency measurements were published.
(754) F. E. Terman and J. M. Pettit, "Electronic Measurements," McGraw-Hill Book Co., Inc., New York, N. Y., 2nd ed.; 1952.
(755) D. D. King, "Measurements at Centimeter Wavelength," D. Van Nostrand Co., Inc., New York, N. Y.; 1952.
(756) F. Benz, "Messtechnic für Funkingenieure," Springer-Verlag, Vienna, Austria; 1952.
The first book is arevision of Terman's 1935 "Measurements in Radio Engineering." It encompasses a broad field, but for all its breadth covers the specialized field of high-frequency measurements very well. The second book limits itself primarily to transmission-line devices and presents the methods and techniques of these measurements. The third book, covering all frequencies, is divided into five parts, the last of which deals with high-frequency measurements. Using the centimeter-kilogram-second system of units, it may be confusing to those accustomed to mks or cgs systems.
A review article on measuring technique and another on instruments were published.
(757) A. F. Harvey, "Instruments for use in the microwave band," Proc. IEE (London), pt. II, vol. 98, pp. 781-789; December, 1951. Discussion, pp. 789-782. Ibid., summary, pt. III, vol. 99, p. 32; January, 1952.
(758) W. Druey, "High-frequency measurement technique, Bull. schweis. ekctrotech. ver., vol. 42, pp. 989-1000; December 15, 1951 (In German). Discussion, pp. 1000-1003 (In German and French).
Impedance Measurements
Progress in impedance measurement can be divided into four categories:
1. Sweep-frequency methods using reflected energy. 2. Other wide-band methods. 3. RF bridges. 4. New techniques required for the measurement of open waveguides and strip transmission lines or "printed microwave circuits."

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Most sweep-frequency methods measure only the magnitude of the reflected wave or of the reflection coefficient, indicating the variation in the magnitude of the terminating impedance with frequency. This is a rapid measurement and allows quick modification and re-observation of results. It usually does not measure the phase of the reflection coefficient. Work was done recently on the development of instruments that measure both magnitude and phase of the reflection coefficient as a function of frequency. These results were displayed on an oscilloscope. At least one of these used an overlay of the Smith chart on the oscilloscope so that the plot was read directly. Long-distance microwave relays presented a rather special need for quick measurement techniques because of the extensive facilities that must be taken out of service during measurement. Here, sweep methods are invaluable.
(759) K. S. Packard, "Automatic Smith-chart Impedance Plotter," paper number 62 presented before the I.R.E. Convention in New York; March, 1952. Summary, PRoc. I.R.E., vol. 40, p. 218; February, 1952.
(760) E. A. N. Whitehead, "A microwave swept-frequency impedance meter," Elliot Jour., vol. I, pp. 57-58; September, 1951.
(761) W. J. Albersheim, "Measuring techniques for broadband, long distance radio relay systems," PROC. I.R.E., vol. 40, pp. 548551; May, 1952.
Several other methods, not sweep frequencies, were reported as being adaptable to use over wide frequency ranges. One used the insertion loss and phase shift of a signal when an unknown is inserted to determine its impedance. This requires the measurement of small voltage and phase shifts, but is independent of the proximity of the unknown to the measuring equipment. The heterodyne method, permitting the standards to be at an intermediate frequency when making measurements at aradio frequency has been extended. Attenuators in the intermediate frequency range have been used for some time in the measurement of insertion loss. Measurements of Q, delay, phase, and impedance are more recent developments. This technique employs a single set of standards over a very wide range of frequencies. It does, however, require the use of a highquality mixer to preserve the accuracy of these standards. Another method of impedance measurement uses amixer as in the heterodyne method but the same signal source for both signal and local oscillator. The magnitude of one is derived from the voltage across the unknown, and the magnitude of the other is derived from the current through the unknown. The IF output is a dc voltage whose amplitude indicates the magnitude of
the resistance of the unknown. A 90-degree phase shift in either signal or local oscillator gives adc output proportional to the reactive component of the unknown. For conductance measurements, avariation of the substitu-
tion method was reported. In this method, the resistive load need not be matched at the frequency used. The signal is rectified and the substitution element used in
the dc load of the rectifier.
(762) D. A. Alsberg, "A precise sweep-frequency method of vector impedance measurement," PROC. I.R.E., vol. 39, pp. 13931400; November, 1951.
(763) D. A. Alsberg, "Principles and applications of 'converters for high-frequency measurements," PROC. I.R.E., vol. 40, pp. 1195-1203; October, 1952.

(764) H. LeCaine, "The Q of amicrowave cavity by comparison with acalibrated high-frequency circuit," PRoc. I.R.E., vol. 40, pp. 155-157; February, 1952.
(765) B. Salzberg and J. W. Marini, "Measurement of impedance and admittance," paper 58, presented IRE Convention, New York, N. Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 218; February, 1952.
(766) W. W. Freeman, Jr., "A high sensitivity method for measuring conductance and capacitance at radio frequencies," paper 30, presented IRE Convention, New York, N. Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 215; February, 1952.
The use of the bridged-T bridge for impedance measurements at 50-100 mc was reported. For lower frequencies, bridges for coaxial-system measurements continue to be popular.
(767) R. F. Proctor, "A bridged-T impedance bridge for the V.H.F. band," Proc. IEE (London), vol. 99, pt. III, p. 105; March, 1952.
(768) H. T. Wilhelm, "Impedance bridges for the megacycle range," Bell Sys. Tech. Jour., vol. 31, pp. 999-1012; September, 1952.
An expanding interest in open waveguides and strip transmission lines (microwave printed circuits) has necessitated the development of different measuring techniques. A method of determining standing-wave ratio on an open waveguide was reported in which the change in input impedance due to movement of a dielectric disk along the open guide was used. Knowing the change in impedance, the standing-wave ratio is found to be the square root of the ratio of maximum and minimum impedance change.
(769) S. W. Attwood and G. Goubau, "Method for open waveguide. standing-wave measurements," paper .51, presented IRE Convention, New York, N. Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 217; February, 1952.
Frequency and Time
Extremely selective absorption of energy in the microwave region by certain atoms and molecules is being used for frequency and time standards. A survey of the methods and known possibilities of these properties was presented and atheoretical short-time accuracy of Ipart in 10" was ascribed to the resonances in molecular and atomic beams and the absorption of microwaves by ammonia. Accuracies for longer periods are expected to average out to even better values. These then, represent our most accurate standards for time and frequency.
A more versatile, if less accurate, frequency calibrator is the crystal type. It is claimed for arecent instrument that a complete range of frequencies can be obtained from the calibrator without loss of the accuracy normally associated with the crystal.
(770) C. H. Townes, "'Atomic' clocks and frequency stabilization
on microwave spectral lines," Jour. Appt. Phys., vol. 22, pp.
1365-1372; November, 1951. (771) D. Cooke, "A self-interpolating crystal calibrator for setting
up and measuring radio frequencies," Elec. Eng. (London), vol. 24, pp. 23-25; January, 1952.
Signal Sources
Recent developments in signal sources indicate acontinuation of the trend away from point-by-point measurements to the faster sweep-frequency methods. In addition, there is a trend toward the complete impedance-measuring device that includes the signal source associated with the impedance-plotting mecha-

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April

nism. Sweeping devices to measure other quantities are also so specialized as to require aspecific signal source which is often built into the equipment.
(772) J. A. Cornell and J. F. Sterner, "Sweep-frequency generator for the U.H.F. television band," Tele-Tech, vol. 11, pp. 38-40, 86,88; February, 1952.
(773) F. P. Blecher, "A wide-band sweep generator," paper 33, presented IRE Convention, New York, N. Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 215; February, 1952.
(774) W. F. Marshall, "Microwave generator with crystal control," Electronics, vol. 24, pp. 92-95; November, 1951.
Power, Detection, and Attenuation
A large amount of attention has been concentrated on the properties of microwave gyrators, circuit elements that do not obey the reciprocity theorem. The microwave gyrator has been realized by making use of the Faraday rotation in pieces of ferrite in awaveguide. It is expected that these lossless broad-band devices may become very useful tools in the field of measurements. Their properties make them suited for electrically controlled variable attenuators, modulators, microwave switches, and one-way transmission systems. A detector based on the wideband absorption of microwaves by thin layers of certain metals used in aGolay pneumatic heat detector was reported. With adetector of 12-mm diameter, signals equivalent to noise measure in the order of 10-8 watt. A study was made of accuracy of bolometer power-measuring devices. This study showed that at frequencies where the bolometer wire became an appreciable portion of awavelength better accuracy is obtained with convectively cooled air-mounted wires than with vacuum-mounted units. A means of obtaining accurate and constant voltages of 1to 100,00012v at all frequencies to 300 mc was developed.
(775) C. L. Hogan, "The ferromagnetic Faraday effect at microwave frequencies and its application, the microwave gyrator," Bell Tech. Jour., vol. 31, pp. 1-31; January, 1952.
(776) H. Theissing, H. J. Merrill, and J. M. McCue, "Measurements of millimeter radiation with the pneumatic heat detector," paper 61, presented IRE Convention, New York, N.Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 218; February, 1952.
(777) M. C. Selby, "Accurate RF microvolts," paper 59, presented IRE Convention, New York, N. Y.; March, 1952. Summary, PROC. I.R.E., vol. 40, p. 218; February, 1952.
(778) H. J. Carlin and M. Sucher, "Accuracy of bolometric power measurements," PRoc. I.R.E., vol. 40, pp. 1042-1048; October, 1952.
(779) K. S. Machin, M. Ryle, and D. D. Vonberg, "The design of an equipment for measuring small radio-frequency noise powers," Proc. IEE (London), vol. 99, pt. III, pp. 127-134; May, 1952.
Video-Frequency Measurements
Recognition of the importance of the phase characteristic of television transmission apparatus is given further emphasis by the introduction of new measuring gear for point-by-point or oscillographic presentation of data. Activity is directed primarily toward accuracy of measurement and convenience of manipulation.
(780) A. Ruhrmann, "Direct reading high frequency phase measurement with frequency curve tracer," Arch. tech. Messen, Issue No. 190; November, 1951.
(781) C. W. Goodchild and R. C. Looser, "Apparatus for the measurement of phase delay in television transmission circuits and in associated apparatus," Inst. Elect. Engrs. Paper 1255 (Television Convention 1952).
(782) G. J. Hunt, "Group-delay Distortion-Measuring Equipment," Inst. Elect. Engrs., Paper 1250 (Television Convention, 1952).

Impedance measurements in the megacycle range is ably reviewed in a survey paper supplemented by an extensive bibliography.
(783) H. T. Wilhelm, "Impedance bridges for the megacycle range," Bell Sys. Tech. Jour., vol. 31, pp. 999-1012; September, 1952.
Interference Measurements
The Central Radio Propagation Laboratory, in cooperation with the military services, is planning aworldwide network of approximately 50 atmospheric-noiserecording stations. The prototype receiver was built and arrangements are progressing for the construction and installation of the field stations.
Co-ordinated studies are being carried on at the University of Florida, the University of Pennsylvania, and several other places, both in this country and abroad, on the desirable characteristics to be measured for various kinds of radio noise.
Telemetering
The FM/FM mobile system made new gains, both in application and in performance. The use of a crystalcontrolled transmitter became standard practice and several manufacturers are now in production of the twowatt version operating in the 220-Mc band. PDM/FM, PPM /AM, or PPM/FM systems are the only pulsemodulated systems in common use, and the FM/FM system has taken the place of the proposed PPM /pulsed RF as the high-performance system. Work is active on a PCM system of modulation.
An outstanding digital telemetering system was described at Long Beach, California. This system is versatile in that it can transmit one channel with 400-cycle response, or 400 channels with one-cycle response each, or any intermediate pairing. The airborne installation incorporates null sensing with servobalancing and analog-to-digital conversion. It transmits intelligence as coded beacon responses at radar repetition rates. On the ground, amicrowave tracking radar receives the pulses and temporarily stores them. After checking for errors, the information is printed to three significant decimal digits.
An improved FM receiver appeared. The receiving station in the field reverted to the earlier design of areceiver and arecorder, since the magnetic tape recordel was demonstrated to possess adequate stability and frequency response. Subsequently, in acentral laboratory the tapes are played back through subcarrier discriminators and the outputs of the various channels simultaneously recorded on various types of permanent recorders. Automatic analysis equipment is still under test.There are anumber of semiautomatic units available.
In the field of subcarrier oscillators, very important advances in the temperature stability characteristic of several types appeared. The general assembly techniques were improved and the corresponding space occupied for a given channel function considerably reduced. Power requirements remain aproblem.

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The potentiometer-type pickup continued to find application for many measurements previously employing inductance-type pickups. Advances were made in the life and stability of this type of pickup, and their ability to withstand shock and vibration was increased. Straingauge elements are still employed, but more often these require either aspecial amplifier or amore complex subcarrier oscillator than the voltage-modulated units. Barium titanate pickups are widely employed, especially for vibration measurements, and several improved designs achieving higher-frequency response are now available.
The problems of over-all reliability of equipment involving chains of individual reliabilities, satisfactory vacuum tubes, and efficient low-weight power supplies still come to the fore in any general discussion among telemetering engineers.
Oscillography
General. Considerable attention was given to the evolution of the general-purpose cathode-ray oscillograph from a waveshape indicator to a measuring instrument reading amplitude and time, either directly calibrated or by substitution methods.
(784) »A true electronic voltmeter," Oscillographer, vol. 13, pp. 9 et. seq.; July-September, 1952.
(785) R. S. Mackay, "Switch provides d-c reference display," Electronics, vol. 25, pp. 23-124; December, 1952.
(786) "A new quantitative 10 megacycle oscillograph," Oscillographer, vol. 13, p. 20; January-March, 1952.
The accuracies of measurement obtained were made possible in part by the development of cathode-ray tubes made to tighter tolerances than those previously available as standard components.
(787) "Tight tolerance cathode-ray tubes,» Electronic Design, vol. A, pp. 6-7; December, 1952.
Electron Optics for Cathode-ray Oscillograph Tubes. Simplified mathematical methods were developed for numerical ray tracing, the prediction of lens focal lengths, and other parameters from the physical dimensions and applied electrode voltages.
(788) P. Grivet, "Cardinal parameters of anew model of an electron tense," Comps. Rend. Acad. Sci. (Paris), vol. 234, pp. 73-75; January, 1952.
(789) J. C. Burfoot, "Numerical ray tracing in electron lenses," Brit. Jour. Appl. Phys., vol. 3, pp. 22-24; January, 1952.
A textbook was published devoted to the basic principles of storage tubes.
(790) M. Knoll and B. Kazan, "Storage Tubes,» John Wiley and Sons, Inc., New York, N. Y., pp. 143; 1952.
The spurious signal on image iconoscopes was greatly reduced by a pulse-control method of maintaining mosaic bias,
(791) R. Theile and F. H. Townsend, "Improvements in image iconoscopes," PROC. I.R.E., vol. 40, pp. 146-154; February, 1952.
and by changes in design and operating conditions.
(792) J. E. Cope, L. W. Germany, and R. Theile, "Improvements in design and operation of the image iconoscope type camera tubes, » Jour. Brit. I.R.E., vol. 12, pp. 139-149; March, 1952.

Studies were made of second-order defocusing effects in electron beams,
(793) J. S. Hickey, Jr. and T. G. Mihran, "The spreading of an electron beam," PROC. I.R.E., vol. 40, p. 994; August, 1952.
and a method of counteracting the defocusing due to space charge by use of amagnetic field was described.
(794) M. E. Hines, "Nullification of space charge effects in aconverging electron beam by amagnetic field," PRoc. I.R.E., vol. 40, pp. 61-64; January, 1952.
A cathode-ray tube having distributed delay-line types of deflection plates was designed and used to record pulses having rise times of 5X10--'9 second, and to observe 3X10 9-cps oscillations at useful amplitudes.
(795) S. T. Smith, R. V. Talbot, and C. H. Smith, Jr., »Cathode-ray tube for recording high speed transients," PROC. I.R.E., vol. 40, pp. 297-303; March, 1952.
A monoscope was designed for artificially duplicating controllable antenna characteristics.
(796) S. T. Smith, »A novel type of monoscope," PROC. I.R.E., vol. 40, pp. 666-668; June, 1952.
The variation in secondary emission over the target plate was obtained by using athree-dimensional target and varying the angle of the primary electrons. A number of electrostatic lenses were described, either uni potential or with low focus voltages with respect to cathode.
(797) E. Regenstreif, »An independent electrostatic lens with minimum elliptical astigmatism," Jour. Phys. Radium, vol. 12, pp. 760-761; July-September, 1951.
(798) C. S. Szegho, "Cathode-ray tube with low focusing voltage," PROC. I.R.E., vol. 40, pp. 937-939; August, 1952.
(799) A. Y. Bentley, K. A. Hoagland, and H. W. Grossbohlin, "Self focusing picture tube," Electronics, vol. 25, pp. 107-109; June, 1952.
An exceptionally stable supply suitable for cathoderay tubes is capable of delivering 1ma at 3 kv with a stability of one part in 104.
(800) J. Templeton, "A high stability high voltage power supply unit," N. Z. Jour. Sci. Tech., vol. 33, pp. 218-223; November, 1951.
Cathode-Ray Oscillograph Applications. A receivingtube-characteristics plotter producing a calibrated family of E0-4,-E, curves was described.
(801) M. L. Kuder, "Electron tube curve generator," Electronics, vol. 25, pp. 118-124; March, 1952.
A number of other oscillographic apparatuses were developed for displaying the characteristics of transistors.
(802) P. J. W. Jochems and F. H. Stieltjes, "Apparatus for testing transistors,» Philips Tech. Rev., vol. 13, pp. 254-265; March, 1952.
(803) G. B. B. Chaplin, "Display of transistor characteristics on the cathode-ray oscillograph," Jour. Sci. Inst. (Brit.), vol. 29, pp. 142-145; May, 1952.
(804) "A Transistor Curve Tracer,» RCA License Laboratory Bulletin LB 882.
A modulation method of displaying nonlinear characteristics of materials under test was described.
(805) H. E. Hollmann, »Polaresistivity and polaristors," PROC, I.R.E., vol. 40, pp. 538-545; May, 1952.

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A method of photographically plotting the instantaneous mean power of complex waves using a sweep and acontinuous motion camera was used for the study of audio signals.
(806) H. W. Curtis, "Measuring the mean power of varying amplitude complex audio waves," PROC. I.R.E., vol. 40, pp. 775-779; July, 1952.
By using a logarithmic amplifier in a cathode-ray oscillograph, it is possible to measure reverberation times directly on the screen.
(807) C. G. Mayo and D. G. Beadle, "The direct measurement of reverberation time," Elec. Eng. (Brit.), vol. 23, pp. 462-465; December, 1951.
A ten-channel amplitude distribution analyser for nuclear studies was built using aK-1059 target tube.
(808) E. Glenn, "A pulse-height distribution analyser," Nucleonics, vol. 9, pp. 24-28; September, 1952.
A transient recorder having sweep durations of 10-8 second was described.
(809) D. R. Hardy, "A high speed transient recorder," Jour. Sci. Inst., vol. 29, pp. 241-242; August, 1952.
Photographic methods suitable for oscillography and television were reviewed.
(810) H. Aberdam, "Photography of oscillograms and television images," Tnute la Radio, pp. 339-342 and 365-368; November and December, 1951.
Image converters were used as high-speed shutters.
(811) J. A. Jenkins and R. A. Chippendale, "The application of image converters to high speed photography," Jour. Brit. IRE, vol. 11, pp. 505-517; November, 1951.
Increasing application of cathode-ray oscillographs in the subaudio field
(812) P. S. Christaldi, "Oscillographic instrumentation for the subaudio field," Trans. IRE, vol. PGI-1, pp. 45-56; May, 1952.
emphasized the importance of the development of adequate transducers.
(813) C. C. Johnson, "A homopolar tachometer for servomechanism application," PROC. I.R.E., vol. 40, pp. 155-157; February, 1952.
A compendium of presently widely scattered source material on transducers and accessories useful in oscillography was made available.
(814) M. T. Nadir, "A Compilation of Analog Transducers," Allen B. Du Mont Laboratories, 1st ed., 68 pp; 1952.
Magnetics
Research and engineering in magnetic materials included, in particular, continued exploration of the ferromagnetic nonmetals, the development of miniature pulse transformers and magnetic amplifiers for computers to meet the needs of the Armed Forces, and work on substitutions for critical elements.
Considerable progress was reported on measuring the properties of magnetic materials up through microwave frequencies and on deriving asuitable correlating theory of the mechanisms of magnetism. A study of the Faraday rotation effect in ferrites at microwave frequencies and the construction of a nonreciprocal waveguide element utilizing this effect, termed the "gyrator," was announced. A conference on magnetism, with an inter-

national roster of speakers and participants, was sponsored by the Office of Naval Research at the University of Maryland on September 2-6, 1952. The papers will be published in a forthcoming issue of the Review of Modern Physics.
(815) C. L. Hogan, "The ferromagnetic Faraday effect at microwave frequencies and its applications--the microwave gyrator," Bell Sys. Tech. Jour., vol. 31, pp. 1-31; January, 1952.
(816) B. Pistonlet, "On the behavior of ferromagnetic powders up to 24,000 megacycles per second," Ann. Telecomm., vol. 7, pp. 2745; January, 1952; pp. 86-97; February, 1952, pp. 127-138; March, 1952 (In French).
(817) J. K. Galt, "Initial permeability and related losses in ferrites," Ceramic Age, vol. 60, pp. 29-33; August, 1952.
(818) L. F. Bates, "Some post-war developments in magnetism," Proc. Roy. Soc. A., vol. 65, pp. 577-594; August 1, 1952.
Ferrites with squared hysteresis loops for magnetic amplifier and computer applications have been achieved through processing and also through the application of suitable stresses to completed cores.
(819) J. J. Went and E. W. Gorter, "Magnetic and electrical properties of Ferroxcube materials," Philips Tech. Rev., vol. 13, pp. 181-193; January, 1952.
(820) V. B. Vonderschmitt, M. J. Olbert and H. B. Stott, "Ferrite applications in electronic components," Electronics, vol. 25, pp. 138-139; March, 1952.
(821) E. Both, "Development and utilization of magnetic ferrites," Ceramic Age, vol. 59, pp. 39-45; April, 1952.
(822) E. Gelbard, "Magnetic properties of ferrite materials," TeleTech, vol. 11, pp. 50-52, 82; May, 1952.
(823) W. Six, "Some applications of Ferroxcube," Philips Tech. Rev., vol. 13, pp. 301-311; May, 1952.
(824) E. Newhall, P. Gomard and A. Ainlay, "Saturable reactors as r-f tuning elements," Electronics, vol. 25, pp. 112-115; September, 1952.
Improved thin tape magnetic cores became commercially available for small transformers. Magnetic amplifier development has taken advantage of ultra-thin tape with rectangular hysteresis loops and half-wave circuitry to achieve small size and high speed. The possibilities of subminiature magnetic amplifiers in combination with transistors for small computers appear challenging on the basis of exploratory work.
(825) E. P. Felch, V. E. Legg and F. G. Merrill, "Magnetic modulators," Electronics, vol. 25, pp. 113-117; February, 1952.
(826) F. E. Butcher and R. Willheim, "Some aspects of magnetic amplifier technique," PROC. I.R.E., vol. 40, pp. 261-270; March, 1952.
(827) F. Benjamin, "Improvements extend magnetic-amplifier applications," Electronics, vol. 25, pp. 119-123; June, 1952.
(828) A. V. Hughes and C. F. Salt, "Magnetic core materials for small power transformers," Elec. Mfg., vol. 49, pp. 133-138, 324; June, 1952.
(829) W. H. Elliot, "Magnetic amplifier definitions," Elec. Mfg., vol. 50, pp. 88-91, 252; July, 1952.
(830) M. F. Littmann, Ultrathin tapes of magnetic alloys with rectangular hysteresis loops," Commun. and Elec., pp. 220223; July, 1952.
(831) C. C. Horstman, "Core materials for small transformers," Tele-Tech, vol. 11, pp. 40-42, 90; October, 1952.
(832) E. A. Sands, "The behavior of rectangular hysteresis loop materials under current pulse conditions," PROC. I.R.E., vol. 40, pp. 1246-1250; October, 1952.
(833) L. J. Johnson, "High speed magnetic amplifier," Elec. Mfg., vol. 50, pp. 98-101, 318; November, 1952.
Design techniques for magnetic powder cores and the appraisal of such cores for military equipment received attention.
(834) H. E. Harris, "Simplified approach to toroidal inductor design," Tele-Tech., vol. 11, pp. 54-56, 107; January, 1952; pp. 52-53, 70; February, 1952.
(835) S. Freedman, "Toroidal coil developments," Radio and Telev., vol. 47, pp. 3-6, 31; April. 1952.
(836) G. R. Polgreen, "Production and application of magnetic powders," GEC Jour., vol. 19, pp. 152-169; July, 1952.

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(837) E. Both, "Magnetic powder cores for military communication equipment," Tele-Tech., vol. 11, pp. 36-38,100; August, 1952.

Two new permanent magnet materials of potential importance, especially in the event of shortages of nickel and cobalt required for Alnico, were announced. One was a bismuth-manganese alloy and the other a ceramic (ferrite) type. Further work on permanent magnets consisting of ultrafine iron powders was carried
out.
(838) J. J. Went, G. W. Rathenau, E. W. Gorter and G. W. Van Oosterhout, "Ferroxdure, aclass of new permanent magnetic materials," Philips Tech. Rev., vol. 13, pp. 194-208; January, 1952.
(839) B. Kapelman, "Permanent magnets from ultrafine iron powders," Elec. Eng., vol. 71, pp. 447-451; May, 1952.
(840) "Navy develops new permanent magnet material called Bismanol," Steel, vol. 131, pp. 76-77; July 28,1952.

The general techniques of magnetic measurements and applications have advanced.
(841) R. F. Lafferty, "Extended Q-meter measurements," Electronics, vol. 24, pp. 126-131; November, 1951.
(842) W. Jellinghaus, "Development of the methods of testing ferromagnetic materials," Arch. f. d. Eisenhuttenwesen, vol. 22, pp. 401-410; November-December, 1951 (In German).
(843) P. M. Prache, "Magnetic cores and shells for communication purposes," Cables and Trans. (Paris), vol. 6, pp. 22-64; January, 1952; pp. 124-164; April, 1952 (In French).
(844) D. C. Dieterly and C. E. Ward, "Wide range ac bridge test for magnetic materials," ASTM Bull., vol. 182, pp. 75-80; May, 1952.
(845) H. W. Lord, "Dynamic hysteresis loop measuring equipment," Elec. Eng., vol. 71, pp. 518-521; June, 1952.

Piezoelectricity

Progress in the physics of this field, with ferroelectricity as the keynote for the year, is an intimate part of the rapidly developing physical picture of the solid state and represents also the most significant advance for piezoelectricity during the year. Important theoretical
papers mark progress in the analyses of the behavior of the piezoelectric resonator and of the transducer and its
coupled field. On the design and development side the high-frequency, thickness-shear quartz plate has attained the status of a primary standard of frequency while the split ring of quartz has invaded the audiofrequency field as afrequency standard. The large number of papers and reports in the several branches of piezoelectricity, including those on the many applications, bring the total number of references in piezo-

electricity for the year 1952 to well over five hundred. A fairly complete bibliography for the year 1951,
which appeared in March, 1952 as an unclassified re-
port to the U. S. Army Signal Corps, included about three hundred titles for that year. A similar bibliog-
raphy for 1952 is in preparation.' The following books, bibliographies, digests, and re-
view articles are noted:

(846) R. G. Breckinridie and H. Thurnauer (editors), "Digest of the

Literature on Dielectrics," National Research Council, vol.

XIV (1950); September, 1951.

(847)

R. F. tals,"

SB.riHte. aJromuro.n,A"ppTih.ePhelyass.t,icvoclo.ns3,tapnpt.s

of piezoelectric 120-124; April,

crys1952.

IThese bibliographies, along with reports on research in the broad field of frequency control, sponsored by the U. S. Army Signal Corps Engineering Laboratories, are available within afew months of their receipt in microcard form through the Office of Naval Research, Library of Congress, Technical Information Division.

(848) W. Shockley (editor), "Imperfections in Nearly Perfect Crystals," John Wiley and Sons, Inc., New York, N. Y., pp. 490; 1952.
(849) J. C. Slater, "The solid staee," Physics Today, vol. 5, pp. 1015; January, 1952.
(850) K. S. Van Dyke and O. M. H. Wall (Wesleyan University), "Bibliography of Piezoelectricity-1951," U. S. Army Signal Corps Contract DA36-039-sc-73, supplementary volume, 7th quarterly report; February 29, 1952.
(851) A. von Hippel, "Piezoelectricity, ferroelectricity and crystal structure," Phys. Rev., vol. 87, pp. 200-201, abstract; July I, 1952.
Ferroelectricity, Antiferr°electricity, and their Applications
Considerable progress was made in understanding ferroelectricity and antiferroelectricity. These are the counterparts in the dielectric field of ferromagnetism and antiferromagnetism in the magnetic field. A theory based on rotatable polar molecules was worked out (Takagi) which shows that crystals become antiferroelectric if the polarizability of the dipoles is small but ferroelectric if the polarizability of the ions becomes larger. This type of theory is applicable to materials similar to C.CI, which may have rotatable dipoles, but not to such materials as BaTiO3,whose dipoles are caused by actual displacement of the centers of charge. In the antiferroelectric state the dipoles are lined up "parallel" to agiven line as in the ferroelectric state, but alternate dipoles are oppositely directed so that, strictly, antiparallelism rather than parallelism exists. A theory
of antiferroelectricity that had been developed for cubic crystals by Kittel was extended to tetragonal structures
by Mason. On the experimental side, new measurements were
reported on the properties of ferroelectric and antiferroelectric crystals. Frazer and Pepinsky have examined
the structure of KH2PO4 (KDP) and showed that at the Curie temperature the PO4 tetrahedron becomes distorted by having the phosphorus atom displaced from the center of the tetrahedron. They regard this change as being the origin of the ferroelectric dipole. The potassium atom also suffers asmall displacement.
Considerable work was done in investigating the domain sizes and domain motion in ferroelectrics. Kanzig and Peter showed that there is aminimum size of about 1,500A for domains in KH 2PO4 for which spontaneous polarization can appear. This was explained by Kanzig as being due to abalance between depolarization energy
and the domain wall energy. In his investigation of the domain structure of barium titanate Merz found that in
addition to 90° walls that have previously been known 180° walls also exist. No evidence has yet been obtained of domain wall motion, but new domains are seen to occur when the electric field is increased. By increasing the C-axis domain-content of the crystal, the hysteresis loop is given square corners and the coercive field is decreased.
A new ferroelectric, ammonium metaphosphate was reported. A large number of measurements were made by Japanese investigators on the properties of BaZr03, PbZr03,PbTiO3, and related compounds, and it was found that they show both ferroelectric and anti-
ferroelectric properties. For a combination of PbZr03

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PROCEEDINGS OF THE I.R.E.

April

and BaZr03,temperature regions occur in which the material is ferroelectric. Below the region the material is antiferroelectric while above the region the material is paraelectric.
The transition in NI 14H 2PO4 (ADP) occurring at 122°K was shown to be an antiferroelectric transition. This was surmised in a theory by Nagamiya and was proved by the work of Mason and Matthias, and of Wood, Merz, and Matthias, who investigated the ND4D2PO4modification. The change in crystal structure is consistent with the arrangement of the hydrogen or the deuterium nuclei in an antiferroelectric state.
The ferroelectric effect was applied in such devices as signal storage devices and dielectric amplifiers which promise to have very wide usage. Anderson described a ferroelectric information storage system, useful for digital computors or telephone switching systems, which has many advantages over conventional storage systems. These systems have the advantage of low power consumption, offer the possibility of storing large amounts of information in asmall space, and are very fast in operation. Another device whose operation depends on the nonlinear response of aferroelectric material is the dielectric amplifier. This device is the analogue of amagnetic amplifier and, like the magnetic amplifier, can effect again in the ratio of the carrier frequency to the signal frequency. Some of the fundamentals of such amplifiers were discussed (Vincent, Pipes); some experimental values were reported by Urkowitz.
(852) Y. Takagi, "Ferroelectricity and antiferroelectricity of acrystal containing rotatable polar molecules," Phys. Rev., vol. 85, pp. 315-324; January, 1952.
(853) C. Kittel, "Theory of antiferroelectric crystals," Phys. Rev., vol. 82, pp. 729; June I, 1951.
(854) W. P. Mason, "Properties of a tetragonal antiferroelectric crystal," Phys. Rev., vol. 88, pp. 480-484; November, 1952.
(855) B. C. Frazer and R. Pepinsky, "Structural changes in the ferroelectric transition of KH2PO4," Phys. Rev., vol. 85, pp. 479-480; February 1, 1952.
(856) W. Kanzig, "Wall energy of ferroelectric domains," Phys. Rev., vol. 87, pp. 385; July 15, 1952.
(857) W. Kanzig and M. Peter, "Critical domain size in ferroelectrics," Phys. Rev., vo.. 85, pp. 940-941; March 1, 1952.
(858) W. J. Merz, "Domain properties in BaTiO3," Phys. Rev., vol. 88, pp. 421; October, 1952.
(859) R. Pepinsky, et al., "A ferroelectric ammonium metaphosphate," Phys. Rev., vol. 86, pp. 793; June 1, 1952.
(860) Nagamiya, "On the theory of the dielectric, piezoelectric, and elastic properties of NH4H3PO4," Prog. in Theor. Phys., vol. 7, p. 3; 1952.
(861) E. Sawaguchi, H. Maniwa, and S. Hoshino, "Antiferroelectric structure of lead zirconate," Phys. Rev., vol. 83, pp. 1078; 1951.
(862) E. Sawaguchi, G. Shirane, and Y. Takagi, "Phase transition in lead zirconate," Jour. Phys. Soc. (Japan), vol. 6, pp. 333; 1951.
(863) W. P. Mason and B. T. Matthias, "Piezoelectric dielectric, and elastic properties of ND4D2PO4," Phys. Rev., vol. 88, pp. 477479; November 1, 1952.
(864) G. Shirane and A. Takeda, "Transition energy and volume change at three transitions in barium titanate," Jour. Phys. Soc. (Japan), vol. 7, pp. 1-4; January-February, 1952.
(865) G. Shirane, "Ferroelectricity and antiferroelectricity in ceramic PbZr03containing Ba or Sr," Phys. Rev., vol. 86, pp. 219227; April 15, 1952.
(866) J. R. Anderson, "Ferroelectric storage elements for digital computors and switching systems," Elec. Eng., vol. 71, pp. 916-922; October, 1952.
(867) E. A. Wood, W. J. Merz, and B. T. Matthias, "Polymorphism of ND4D2PO4," Phys. Rev., vol. 87, pp. 544; August 1, 1952.
(868) A. M. Vincent, "Dielectric amplifier fundamentals," Electronics, vol. 24, pp. 84-88; December, 1951.
(869) L. A. Pipes, 4A mathematical analysis of a dielectric amplifier," Jour. Apl. Phys., vol. 23, pp. 818-824; August, 1952.
(870) H. Urkowitz, "A ferroelectric amplifier," PRoc. I.R.E., vol. 40, pp. 232; February, 1952.

Resonators
A new level of performance for thickness-shear resonators of quartz has been attained in AT-cut plates in disk form with spherical surfaces, fused mountings, and scrupulous attention to surface finish, cleanliness and hermetic sealing. These plate make primary, standards of frequency in the 3- to 20-mc range. The use of long bars of quartz in flexure as audio-frequency standards has not been common because of the unavailability and high cost of quartz in large size. The straight bar now promises to be superseded by anearly complete ring of quartz undergoing the flexure in the plane of the ring. For the same length of flexing strip (now circumference of the ring), upon which the frequency of resonance depends, the requirement as to maximum over-all dimension of the original piece of
quartz rock is greatly reduced. Local internal heating of quartz plates as alimiting factor in frequency constancy for crystal-controlled oscillators, particularly if the
amplitude is large and is variable, is receiving study as is also the distribution of the amplitude of vibration throughout thickness-shear quartz resonators. A recent theoretical analysis of the thickness-shear resonator has been extended to include the secondary effects of the piezoelectric properties on the stiffness and thus on the frequencies of resonance. A method is demonstrated for measuring the parameters of quartz resonators which is particularly suited to the very high-resonance frequencies. In the instrument which has been developed
for such measurements, in the Signal Corps Engineering Laboratories, the deflections as crystal resonances are passed through are compared with reference deflections which are either caused by or modified by a standard capacitance. Several studies have been underway in the use of quartz as amechanical filter. The elimination of unwanted modes in filter crystals is the subject of one of a half dozen papers (others not here listed) by Bech-
mann from his new location in the Radio Experimental and Development Branch Laboratories, Dollis Hill, of the British Post Office Engineering Department, these appearing mostly in the British journals and dealing largely with resonator problems.
(871) R. Bechmann, "Single response thickness-shear mode resonators using circular bevelled plates," Jour. Sci. Inste. (London), vol. 29, pp. 73-76; March, 1952.
(872) V. E. Bottom (Colorado A. and M. Coll.), "Mounting Techniques for Improved Heat Dissipation in Quartz Crystal Units," U. S. Army Signal Corps Contr. DA36-039-sc-5485, Quarterly Progress Report No. 1; February 28-May 30, 1951.
(873) E. A. Gerber, "Quartz-crystal measurement at 10 to 180 megacycles," PROC. I.R.E., vol. 40, pp. 36-40; January, 1952.
(874) R. D. Mindlin, "Forced thickness-shear and flexural vibrations of piezoelectric crystal plates," Jour. Appl. Phys., vol. 23, pp. 83-88; January, 1952.
(875) C. R. Mingins, et al. (Tufts Coll.), "An Investigation of the Characteristics of Electromechanical Filters," U. S. Army Signal Corps Contr. DA36-039-sc-5402, 3rd Quarterly Report; August 1, 1952.
(876) E. J. Post, "A new crystal cut for quartz with zero tempera-
ture coefficient," Appl. Sci. Res., vol. BI, pp. 420-428; 1950.
Abstract: PROC. I.R.E., vol. 40, pp. 889, Ab. 1641; July, 1952. (877) E. J. Post, "Note on safe resonator current of piezoelectric
elements," PROC. I.R.E., vol. 40, pp. 835; July, 1952. (878) J. E. Thwaites, "Quartz vibrators for audio frequencies," Proc.
IEE (London), vol. 99, pt. IV; 1952. (879) M. D. Waller, "Vibrations of free plates: line symmetry; cor-
responding modes," Proc. Roy. Soc., vol. 211, pp. 265-276; February 21, 1952.

1953

Radio Progress During 1952

495

(880) A. W. Warner, "High frequency crystal units for primary frequency standards," PROC. I.R.E., vol. 40, pp. 1030-1033; September, 1952.
Transducers
Great progress has been made in the formal analysis of the piezoelectric transducer and there have been a number of reports on design and performance characteristics. New developments in recording instruments for wave propagation and viscosity measurements give promise of new measuring and testing techniques.
(881) M. Alixant, "Ultrasonic generators and their applications," Radio Tech. Dig. (France), vol. 5, pp. 271-278, 299-325; 1951.
(882) R. Barthel and A. W. Nolte, "A precise recording ultrasonic interferometer and its applicaton to dispersion tests in liquids," Jour. Acous. Soc. Amer., vol. 24, pp. 8-15; January, 1952.
(883) F. E. Borgnis (Calif. Inst. of Tech.), "A general theory of the acoustic interferometer for plane waves," Contract Nonr220(02), Task No. NR384-404, Technical Report No. 3; January 25, 1952. (Submitted by W. G. Cadi, Project Director).
(884) A. Skudrzyk, "The general theory of the acoustic transmitter and receiver, its use to obtain the equivalent circuit diagrams of a magnetostrictive oscillator and a quartz transducer," Nuovo Cim., vol. 7, pp. 416-434 (Suppl. No. 2, 1950), in German. (Phys. Abstr., vol. 55, pp. 303, AB.2533; April, 1952.)
(885) Colloquium over Ultrasonore Trillingen (International Conference on Ultrasonics--Brussels; June 7, 8, 9, 1951)--Kon. VI. Acad. Weten. Let. Sch. Kunst. Belgie; 1951. (Jour. Acous. Soc. Amer., vol. 24, pp. 553; September, 1952.)
Applications of Piezoelectric Devices
There have been anumber of confirmed diagnoses of cancerous tissue by ultrasonic ranging techniques using aquartz element.
(886) J. M. Reid and J. J. Wild, "Ultrasonic ranging for cancer diagnosis," Electronics, vol. 25, pp. 136-138; July, 1952.
Among many papers on experiment and measurement in which the piezoelectric crystal is the key tool, the following are listed as including some treatment of the piezoelectric device as well as of the findings of the investigation. In one, the quartz crystal traces the force continuously throughout the impact of the two metal bodies. The comparison of observations with theory sheds considerable light on the "flow-pressure" concept of Vincent (1900). In asecond paper, abarium titanate transducer which is capable of large amplitude is used to strike and/or to cause sliding of surface on surface in the development of a technique for studying wear on telephone switching apparatus. The large part in wear which is played by sliding as compared with striking is beautifully demonstrated. Another paper extends a technique of measuring ultrasonic propagation constants to the analysis of the contribution of their lengths and of the different parts of the chains of molecules in liquid and solid polymers to their viscoelastic properties. In afourth paper which uses pulse techniques to measure ultrasonic attenuation in steel in the 5to 50 mc/sec range, the importance of a buffer of water between transducer and steel emerges along with the dependence of attenuation upon the heat treatment (and grain size) of the steel. In another paper, interferometric measurements of the viscosity of carbon dioxide and of ethylene at ultrasonic frequencies yield absorption coefficients one thousand-fold larger than are yielded by classical low-frequency or transpiration methods.

(887) A. W. Crook, "A study of some impacts between metal bodies by a piezo-electric method," Proc. Roy. Soc. A, vol. 212, pp. 377-390; May 7, 1952.
(888) W. P. Mason and H. J. McSkimin, "Mechanical properties of polymers at ultrasonic frequencies," Bell Sys. Tech. Jour., vol. 31, pp. 122-171; January, 1952.
(889) W. P. Mason and S. D. White, "New techniques for measuring forces and wear in telephone switching apparatus," Bell Sys. Tech. Jour., vol. 31, pp. 469-503; May, 1952.
(890) H. D. Parbrook and E. G. Richardson, "Propagation of ultrasonic waves in vapours near the critical point," Proc. Phys. Soc. B, vol. 65, pp. 437-444; June, 1952.
(891) R. L. Roderick and R. Truell, "The measurement of ultrasonic attenuation in solids by the pulse technique and some results in steel," Jour. Appl. Phys., vol. 23, pp. 267-279; February, 1952.
Quality Control
The application of statistical quality control expanded in the electronics industry. The ever-increasing need for greater reliability in both military and commercial applications of electronics resulted in improved techniques for assessing the quality of both components and systems.
(892) F. Ennerson, R. Fleischman, and D. Rosenberg, "A production experiment using attribute data," Indus. Quality Control, vol. VIII, p. 41; March, 1952.
(893) E. D. Goddess, "Rating new test methods," Electronics, vol. 5, p. 101; April, 1952.
(894) R. D. Guild, "Correlation of conventional and accelerated test conditions for heater burnouts by the logarithmic normal distribution," Indus. Quality Control, vol. IX, pp. 27-30; November, 1952.
(895) R. S. Hoff and R. C. Johnson, "A statistical approach to the measurement of atmospheric noise," PROC. I.R.E., vol. 40, p. 185; February, 1952.
(896) R. McGhee, "Process control in a development laboratory," Proc. Middle Atlantic Regional Conference, American Society for Quality Control, p. 85; March, 1952.
(897) H. G. Romig, "Quality control techniques for electronic components," Quality Control Conference .Papers 1952, Sixth Annual Convention, American Society for Quality Control, Syracuse, N. Y.; May 22-24, 1952.
(898) D. Rosenberg and F. Ennerson, "Production research in the manufacture of hearing aid tubes," Indus. Quality Control, vol. VIII, p. 94; May, 1952.
(899) B. W. Squier, Jr., "Quality control of TV tubes," Radio and Telev. News, vol. 47, p. 49; February, 1952.
(899A) "Inspection Bulletin on Sampling Procedures," R.T.M.A. Eng. Bull. No. 42; 1952.
Antennas, Waveguides, and Transmission Lines
Antenna Theory
Significant progress was made in advancing the theory of cylindrical antennas by developing new procedures and methods for solving Hallen's integral equation.
(900) A. Zinke, "A new solution for the current and voltage distributions on cylindrical, ellipsoidal, conical, or other rotationally symmetrical antennas," Frequenz, vol. 6, pp. 57-65; March, 1952.
(901) R. King, "An improved theory of the receiving antenna," PROC. I.R.E., vol. 40, pp. 1113-1120; September, 1952.
(902) R. King, "An Alternative Method of Solving Hallen's Integral Equation and Its Application to Antennas Near Resonance," Cruft Laboratory Technical Report No. 154; July, 1952.
(903) R. King, "Theory of electrically short transmitting and receiving antennas, »Jour. Appt. Phys., vol. 23, pp. 1174-1187; October, 1952; Cruft Laboratory Technical Report No. 141; March, 1952.
Coupled antennas were investigated extensively, both theoretically and experimentally.
(904) L. Lewin, "Mutual impedance of wire aerials," Wireless Eng., vol. 28, pp. 352-355; December, 1951.
(905) R. King, "Self- and mutual impedance of parallel identical antennas," PROC. I.R.E., vol. 40, pp. 981-988; August, 1952.

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April

(906) L. S. Palmer, "Radiation or diffraction patterns close to receiving antennas," Jour. Appl. Phys., vol. 23, pp. 289-290; February, 1952.
(907) T. Morita and C. E. Faflick, "The measurement of current distributions along coupled antennas and folded dipoles," PROC. I.R.E., vol. 39, pp. 1561-1565; December, 1951.
Extensive theoretical and experimental work was done on the problem of scattering from cylindrical antennas. In particular, an important new experimental method for measuring back-scattering was developed.
(908) C. T. Tai, "Electromagnetic back-scattering from cylindrical wires," Jour. Appt. Phys., vol. 23, pp. 909-915; August, 1952.
(909) S. H. Dike and D. D. King, "The absorption gain and backscattering cross section of the cylindrical antenna," PROC. I.R.E., vol. 40, pp. 853-860; July, 1952.
(910) V. Twersky, "Multiple scattering of radiation by an arbitrary planar configuration of parallel cylinders and by two parallel cylinders," Jour. Appl. Phys., vol. 23, pp. 407-414; April, 1952.
The problem of short electric and magnetic dipoles in and near the earth was investigated.
(911) J. R. Wait, "Magnetic dipole antenna immersed in aconducting medium," PROC. I.R.E., vol. 40, pp. 1244-1245; October, 1952.
(912) R. F. Proctor, "Input impedance of horizontal dipole aerials at low heights above the ground," Proc. I.R.E. (Australia), vol. 13, pp. 58-61; 1952.
Basic Antenna Types
Several papers appeared dealing with radiation patterns of antennas of different types.
(913) J. E. Storer, "Radiation pattern of an antenna over acircular ground screen," Jour. Appt. Phys., vol. 23, pp. 588-593; May, 1952.
The radiation characteristics of helical antennas were analyzed. A discussion of anomalous behavior of the modes of propagation and an extensive bibliography are included in the first paper.
(914) S. Sensiper, "Electromagnetic Wave Propagation on Helical Conductors," M.I.T. Laboratory for Electronics Report No. 194, Cambridge, Mass.; May, 1952.
(915) C. C. Haycock and J. S. Ajioka, "Radiation characteristics of helical antennas of few turns," Pxoc. I.R.E., vol. 40, pp. 989991; August, 1952.
The theory of the continuous-sheet model and the thin helical wire was developed and compared with experimental results on delay lines and helical antennas.
(916) E. Roubine, "Etudes des Ondes Electromagnetiques Guidee par les Circuits en Helice," Annales des Telecommunications, vol. 7, pp. 205-216; May, 1952; pp. 262-275; June, 1952; pp. 310-324; July-August, 1952.
A nonuniform dielectric transmission line made up of rods alternating with disks of high dielectric constant was used to radiate abroadside pattern.
(917) G. Mueller, "A broadside dielectric antenna," PROC. I.R.E., vol. 40, pp. 71-75; January, 1952.
A comprehensive study of dielectric antennas includes radiation patterns for dielectric cylinders and cones excited through holes in the broad face of awaveguide and for linear arrays of such elements. The theory of modes for dielectric cylinders with or without a central conductor was discussed together with the coupling of these cylinders to awaveguide.
(918) M. Bouix, "Contribution a l'Etude des Antennes Dielectriques," Ann. Tekcomm., vol. 7, pp. 217-238; May, 1952; pp. 276-295; June, 1952, pp. 336-348; July-August, 1952, pp. 350363; September, 1952.

Many advances in the applications of antennas, particularly for microwave frequencies, were made through the use of improved techniques and increased understanding of the theory. The adaptation of antennas to meet the specific requirements of high-speed aircraft and guided missiles is significant.
A new type of microwave lens, where the artificial dielectric is made of perforated metallic plates, was reported.
(919) J. C. Simon, "Un Nouveau Type de Lentilles en Hyperfrequencies," L'Onde Electrique Ap., vol. 32, pp. 181-189; May, 1952.
Microwave antennas for shaped beams continued to receive attention. Doubly curved reflectors, antennapattern calculations, and antenna theory were discussed.
(920) A. S. Dunbar, "On the theory of antenna beam shaping," Jour. Appt. Phys., vol. 23, p. 847; August, 1952.
(921) R. J. Stegen, "Slot radiators and arrays at x-band," TRANS. I.R.E., Prof. Gp. Ant. Prop. PGAP-2, p. 62; February, 1952.
Increased activity occurred in microwave scanning antennas. Among the papers that appeared were discussions on optical theory for application to scanner design and the application of optical systems to scanners.
(922) J. E. Eaton, "Zero phase-front in microwave optics," TRANS I.R.E., Prof. Gp. Ant. Prop. PGAP-1, p. 38; February, 1952
Ferrites appear to have application to microwave scanners.
(923) A. J. Simmons and H. N. Chait, "Microwave antenna ferrite applications," Electronics, vol. 25, p. 156; June, 1952.
Considerable effort was devoted to the problem of flush mounting uhf and vhf antennas in high-speed aircraft.
(924) R. H. J. Cary, "The slot aerial and its application to aircraft," Proc. IEE (London), vol. 29, pt. III, pp. 187-196; July, 1952.
(925) J. V. N. Granger, "Design limitations on aircraft antenna systems," Aero. Eng. Rev., pp. 82-88; May, 1952.
(926) R. H. J. Cary, "A survey of external and suppressed aircraft aerials for use in the high-frequency band," Proc. IEE (London), vol. 29, pt. III, pp. 197-213; July, 1952.
(927) R. G. Mirimanov, "The radiation resistance of adipole near an ellipsoid of revolution of good conductivity," C. R. Acad. Sci. (U.R.S.S.), vol. 80, no. 2, pp. 189-192; September 11, 1951.
Several new books on antenna theory and engineering were published during the year.
(928) D. D. King, "Measurements at Centimeter Wavelength," D. Van Nostrand Co., Inc., New York, N. Y.
(929) E. A. Laport, "Radio Antenna Engineering," McGraw-Hill Book Co., Inc., New York, N. Y.
(930) S. S. Schelkunoff and H. T. Friis, "Antennas, Theory and Practice," John Wiley and Sons, New York, N. Y.
(931) S. S. Schelkunoff, "Advanced Antenna Theory," John Wiley and Sons, New York, N. Y.
Transmission Lines and Microwave Circuits
Low-loss microwave Faraday rotation was realized. In this development, aferrite material within awaveguide and in the presence of an unvarying magnetic field accomplishes rotation of the plane of polarization. This action has promise of wide application in that (1) it provides a means of electric control of polarization within awaveguide and (2) the rotation is not reciprocal. The nonreciprocal property makes possible the construction of agyrator, aone-way transmission system, and the like. Theory and applications were described and arelated problem was discussed.

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(932) C. L. Hogan, "The ferromagnetic faraday effect at microwave frequencies and its applications--the microwave gyrator," Bell Sys. Tech. Jour., vol. 31, pp. 1-31; January, 1952.
(933) C. H. Luhrs, "Correlation of the Faraday and Kerr magnetooptical effects in transmission-line terms," Flux. I.R.E., vol. 40, pp. 76-78; January, 1952.
(934) S. A. Schelkunoff, "Generalized telegraphist's equations for waveguides," Bell Sys. Tech. Jour., vol. 31, pp. 784-801; July, 1952.
Several groups announced advances concerning bandwidth and directivity of directional couplers. The Dolph-Tchebyscheff array distributions, as well as other tapered coupling functions, were applied to directionalcoupler design with excellent results. Several papers also described directional couplers providing very tight coupling. In particular, a broad-band 3-db directional coupler was mentioned having excellent characteristics as ahybrid junction. Several novel circuit applications of directional couplers were described. In one application, impedances that are calculable from electromagnetic theory are shown to be of interest, possibly for use as standards.

Several basic theoretical papers on transmission lines, transmission-line junctions, and laminated transmission lines were published.
(944) M. Namiki and H. Takahashi, "Some variational principles for problems in transmission lines," Jour. Appl. Phys., vol. 23, pp. 1056-1057; September, 1952.
(945) T. Teichmann, "Completeness relations for loss-free microwave junctions," Jour. Appl. Phys., vol. 23, pp. 701-710; July, 1952.
(946) S. P. Morgan, Jr., "Mathematical theory of laminated transmission lines," Bell Sys. Tech. Jour., vol. 31, pp. 883-949; September, 1952.
Problems encountered in the use of multimode transmission lines were explained.
(947) A. P. King, "Dominant wave transmission characteristics of a multimode round waveguide," PROC. I.R.E., vol. 40, pp. 966969; August, 1952.
(948) W. Kummer, "Impedance measurement technique for twomode guides," TRANS. I.R.E., PGAP-1, pp. 148-152; February, 1952.
Two papers on filters or filter-like structures appeared.
(949) E. T. Jaynes, "Concepts and measurement of impedance in periodically loaded waveguides," Jour. Appl. Phys., vol. 23, pp. 1077-1084; October, 1952.
(950) H. J. Riblet, "Synthesis of narrow-band direct-coupled filters," Paoc. I.R.E., vol. 40, pp. 1219-1223; October, 1952.

Theoretical and experimental procedures for determining the electromagnetic field inside a resonant cavity was proposed.
(951) I. C. Maier, Jr. and J. C. Slater, "Field strength measurements
in resonant cavities," Jour. Ape Phys., vol. 23, pp. 68-77;
January, 1952. (952) J. C. Simons and J. C. Slater, "Electromagnetic resonant be-
havior of aconfocal spheroidal cavity system in the microwave
region," /our. Appl. Phys., vol. 23, pp. 29-30; January, 1952.

Novel waveguide circuits were introduced.
(953) R. H. Reed, "Modified magic tee phase-shifter," TRANS. I.R.E., PGAP-1, pp. 126-134; February, 1952.
(954) A. J. Simmons, "A broadband microwave quarter-wave plate," TRANS. I.R.E., PGAP-1, pp. 123-125; February, 1952; PROC. I.R.E., vol. 40, pp. 1089-1090; September, 1952.

Fig. 13--Microstrip balanced crystal mixer and 3-stage preamplifier compared with the equivalent waveguide junction and conventional amplifier. (Federal Telecommunication Laboratories).
(935) S. E. Miller and W. W. Mumford, "Multi-element directional couplers," PROC. I.R.E., vol. 40, pp. 1071-1078; September, 1952.
(936) H. J. Riblet, "Super directivity with directional coupler arrays," PROC. I.R.E., vol. 40, pp. 994-995; August, 1952.
(937) H. J. Riblet, "The short-slot hybrid junction," PROC. I.R.E., vol. 40, pp. 180-184; February, 1952.
(938) W. C. Jakes, Jr., "Broad-band matching with a directional coupler,» PROC. I.R.E., vol. 40, pp. 1216-1218; October, 1952.
(939) W. J. Van de Lindt, "Application of multi-hole coupling to the design of avariable and calibrated waveguide attenuator and impedance," Philips Res. Rep., vol. 7, pp. 28-35; February, 1952.
(940) L. Lewin, "The impedance of unsymmetrical strips in rectangular waveguides," Prot. IEE (London), vol. 99, pt. IV, pp. 168176; July, 1952.

A number of papers appeared on slotted-line measurements.
(955) H. H. Meinke, "Circular measuring lines with visual indication for frequencies from 108 to 3X 10"," Fernmekletechnisch Zeitschrift (FTZ), vol. 5, pp. 583-584; September, 1952.
(956) F. Tischer, "Helical measuring line for microwaves," Zest. Angew. Physik, vol. 4; September, 1952.
The problem of surface-wave transmission lines is intimately connected with that of the travelling-wave antenna. Work was done on both, but only papers concerned with the first are listed here.
(957) H. Kaden, "Fortschritte in der Theorie der Drahtwellen,» Arch. ekkt. übertraguq, vol. 5, pp. 399-414; 1951.
(958) R. Adler, "Waves on inhomogeneous cylindrical structures,» PRoc. I.R.E., vol. 40, pp. 339-348; March, 1952.
(959) R. B. Dyott, "The launching of electromagnetic waves on a cylindrical conductor, » Prot. IEE (London), Pt. III, vol. 99, no. 62, pp. 408-413; November, 1952.

A few papers appeared improving the general knowledge of aperture coupling and providing basic design information. In particular, the applicability of Bethe's aperture theory was extended.
(941) S. B. Cohn, "Microwave coupling by large apertures,» PROC. I.R.E., vol. 40, pp. 696-699; June, 1952.
(942) S. B. Cohn, "The electric polarizability of apertures of arbitrary shape," PROC. I.R.E., vol. 40, p. 1069; September, 1952.
(943) I. Reingold, J. L. Carter, and K. Garoff, "Single- and multi-iris resonant structures, » PROC. I.R.E., vol. 40, p. 861; July, 1952.

Wave Propagation
Tropospheric Propagation
Propagation Well Beyond the Horizon. Experimental evidence continued to appear in the literature concerning the weak but apparently reliable tropospheric fields propagated several hundred miles beyond the horizon at all vhf and microwave frequencies. Reports on tests on

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April

3,700 and 500 mc in northeastern United States in 1950-1951
(960) K. Buffington, "Radio transmission beyond the horizon in the 40-4000 mc band," PROC. I.R.E. (in press).
summarize the median fields beyond the horizon out to several hundreds of miles as being 50 to 90 db below free space but tens or hundreds of db greater than predicted by conventional theory of propagation around a smooth earth under standard refraction conditions. Antenna gains and beam widths seem to be roughly maintained, in contrast to the original predictions of the turbulent scattering theory under the assumption of blob size small compared to antenna aperture dimensions. The quality of a sound channel transmitted on a 535-mc carrier was reported limited only by noise level, rather than by multipath effects, and the pulse broadening of 1.5-µsec pulses was usually
less than afew tenths of amicrosecond, indicating that bandwidths of afew megacycles may be possible for this type of propagation. These tests indicate that sufficiently high power and antenna gains will make such circuits reliable for point-to-point hops of several hundred miles over difficult terrain.

(961) T. J. Carroll, "Normal tropospheric propagation deep into the earth's shadow: the present status of suggested explanations," TRANS. I.R.E., P.G.A.P., vol. 3, pp. 6-11; August, 1952.
(962) J. Feinstein, "The role of partial reflections in tropospheric propagation beyond the horizon," TRANS. I.R.E. P.G.A.P., vol. 2, pp. 2-8; March, 1952; vol. 3, pp. 101-111; August, 1952.
(963) T. J. Carroll, "Internal reflection in the troposphere and propagation beyond the horizon," TRANS. I.R.E., P.G.A.P., vol. 2, pp. 9-27; March, 1952; vol. 3, pp. 84-100; August, 1952.
(964) J. F. Colwell and L. J. Anderson, "Concerning the radio field due to internal reflections in the stratified troposphere," TRANS. I.R.E., P.G.A.P., vol. 3, pp. 117-125; August, 1952.
(965) M. Katzin, "Tropospheric propagation beyond the horizon," TRANS. I.R.E., P.G.A.P., vol. 3, pp. 112-116; August, 1952.
The ultimate decision may be largely determined by direct measurement of the actual intensity, scale, and height distribution of tropospheric turbulence at different times and places. Fortunately, the recently developed microwave refractometer measures directly and almost arbitrarily rapidly the index of refraction of a gas such as moist air, and the instrument has not been made airborne. Profiles of index of refraction versus height in the troposphere can now be directly measured, including fluctuations due to turbulence or other motions of the atmosphere affecting the index of refraction.
(966) C. M. Crain, "Directly recorded tropospheric refractive-index fluctuations and profiles," TRANS. I.R.E., P.G.A.P., vol. 3, pp. 79-83; August, 1952.
(967) G. Birnbaum, H. E. Bussey, and R. R. Larson, "The microwave measurement of variations in atmospheric refractive index," TRANS. I.R.E., P.G.A.P., vol. 3, pp. 74-78; August, 1952.

The first attempt to use such microwave refractometer data to estimate how intensity of turbulence decreases with height was published.
(968) W. E. Gordon, "Statistical Fluctuations in the Atmosphere," Proc. 2nd Meeting Joint Commission on Radio-Meteorology, URSI, Rue des Minimes 42, Brussels, pp. 74-77; 1951.

Fig. 14--Weather echoes photographed on the RHI 'scope of an AN/CPS-9 radar. The two perfect marks are 5and 10 mile slantrange marks; 10 and 20 thousand foot elevation lines are also visible. All echoes in the first 3 miles are from ground targets. The echoes near 20 thousand feet and above are from snow clouds, those near 10 thousand feet are snow showers swept several miles horizontally by surface winds, and the weak horizontal echo at 8 thousand feet is the melting level "bright band." (JILT.)
The explanation of these reliable, though weak and fading, tropospheric fields became the center of a spirited and as yet unresolved controversy. The first suggested explanation attributed the fields to scattering by omnipresent blobs of atmospheric inhomogeneity in the upper air high over the middle of the path, caused by atmospheric turbulence. The alternative suggestion attributes the fields to apartial internal reflection from the normal atmosphere itself, which is a horizontally stratified inhomogeneous medium under normal conditions, because gravitational forces cause the index of refraction to decrease monotonically with height in the normal troposphere.

Microwave Fading over Optical Paths. Frequencyselective fading, caused by the presence of one or more paths that have slightly different lengths and hence different relative phases of their signals on arrival at the receiver, sets alimit to the usable bandwidth of asingle communication channel. For two typical microwave overland paths in New Jersey, tropospheric path differences of the order of one to seven feet were measured directly and correspond to time delays of a few millimicroseconds. The methods employed involved both sweeping acarrier over an 11-per cent frequency range in the 4,000-mc region and the use of pulses only afew millimicroseconds long. Such fine-grained investigations mark the advent of millimicrosecond time measurements and the use of traveling-wave tubes in tropospheric propagation measurements.
Momentary deep fades on optical overwater microwave paths were observed for some years. Experimental observations from New Zealand
(969) D. G. Kiely and W. R. Carter, "An experimental study of fading in propagation at 3-cm wavelength over asea path," Jour. IEE (London), vol. 99, pp. 53-60; March, 1952.
on a39-mile microwave overwater link indicated that the explanation must lie both in the motion of the lobe interference pattern across the receiving antenna and in some additional atmospheric mechanism (such as

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atmospheric turbulence perhaps) that makes direct and sea-reflected signals almost exactly equal in magnitude and their resultant very small when they arrive in phase opposition at the receiving antenna.
(970) A. B. Crawford and W. C. Jakes, Jr., "Selective fading of microwaves," Bell Sys. Tech. Jour., vol. 31, pp. 68-90; January, 1952.
(971) 0. E. DeLange, "Propagation studies at microwave frequencies by means of very short pulses," Bell Sys. Tech. Jour., vol. 31, pp. 91-103; January, 1952.
Velocity of Propagation. A new method of measurement of the velocity of propagation of 1.25-cm waves by amethod analogous to the Michelson interferometer in optics gave the vacuum value of 299,792.6+0.7 km. The value confirms the general tendency of recent measurements to yield avalue 13 to 20 km higher than that commonly accepted a decade ago for this fundamental physical constant.
(972) K. D. Froome, "A new determination of the velocity of electromagnetic radiation by microwave interferometry," Nature, vol. 169, pp. 107,108; January, 1952.
Frequency-Spectrum Conservation. A report issued by the IRE-RTM A Joint Technical Advisory Committee contains summary chapters on propagation characteristics 30-3000 Mc by C. R. Burrows, and 3-300 KMc by G. C. Southworth.
(973) Joint Technical Advisory Committee, IRE-RTMA, "Radio Spectrum Conservation," McGraw Hill-Book Co., Inc., New York, N. Y., pp. 91-125; 1952.
These chapters aim to survey in as simple amanner as possible the broad features of propagation knowledge that must influence wise choice of frequency bands in the vast portion of the radio spectrum in which the troposphere is the dominant influence.
Radio Meteorology. Since 1945 there have been several active programs of research in radio meteorology, with particular attention directed toward microwave scattering by raindrops, snowflakes, and cloud particles, Progress was made toward a better understanding of the scattering processes that are of interest to those wishing to eliminate weather echoes from radar scopes, as well as to those who interpret weather echoes usefully, and that are of obvious importance to anyone studying tropospheric propagation. Because most of the important technical developments were described in report form, not widely available, it seems best to mention each major research project and describe its recent accomplishments.
The Signal Corps Engineering Laboratories at Belmar, New Jersey maintained aWeather Radar Section, which has engineered several unusual equipments. First was the CPS-9, a powerful X-band radar especially designed for the Air Weather Service, and now in production.
(974) E. L. Williams, "Progress Report on the AN/CPS-9 Radar Program," Proc. Third Radar Weather Conf., McGill Univ., Canada, pp. C2I-24; September, 1952.
Second was acloud base and top indicator, apowerful K-band set normally arranged to point vertically and plot the range (i.e., altitude) of any clouds or cloud layers passing overhead.

(975) F. W. Fisher, W. B. Gould, and C. L. Greenslit, "Radar cloud base and top indicator," Proc. Third Radar Weather Conf., McGill Univ., Canada, pp. El-8; September, 1952.
Due to the very small particle size of fair-weather cumulus (less than 20 microns), some of these are not detected; most other clouds leave clear records. This type of radar also detects angels in the lower atmosphere almost continuously, but these echoes are easily distinguished from clouds.
The Signal Corps has continuously sponsored since 1946 aresearch project in the Meteorology Department at the Massachusetts Institute of Technology. This project has concentrated on accurate measurement of both the radar echo and meteorological paramenters of precipitation. The objectives are to learn more about the scattering process from different types of natural precipitation, as compared with idealized, uniform, spherical particles, and also to advance the usefulness of radar techniques in meteorological research an weather observation. Very careful measurements indicate that radar echoes at 10- and 3-cms wavelength from rain are consistently 6or 7db lower than would be anticipated from measured rain rates at the ground or from liquid water contents measured aloft by aircraft.
(976) P. M. Austin and H. E. Foster, "Note on comparison of liquid water content of air with radar reflectivity," Jour. Met., vol. 7, pp. 160-161; April, 1950.
(977) P. M. Austin, "Comparison of Average Signal Intensity with Rainfall Rate," Proc. Conf. on Water Resources, Bul. 41, Illinois State Water Survey, pp. 227-233; October, 1951.
Both observation and theory have established that the nature of the fluctuating character of weather echoes can reveal information about the relative velocities of raindrops, turbulence, and other motions within precipitation.
(978) A. Fleisher, "The Information Obtainable from Fluctuation Measurements," Proc. Third Radar Weather Conf., McGill Univ., Canada, pp. G9-14; September, 1952.
Through regular use of radar and aircraft during storms, much has been learned about the precipitation forms, processes, and flight conditions occurring within them as related to the radar information.
(979) P. M. Austin and A. C. Bemis, "A quantitative study of the 'bright band' in radar precipitation echoes," Jour. Met., vol. 7, pp. 145-151; April, 1950.
(980) H. E. Foster, "The Use of Radar in Weather Forecasting with Particular Reference to Radar Set AN/CPS-9," Tech. Rep. No. 20, M.I.T. Weather Radar Research, Cambridge, Mass.; September, 1952.
(981) R. M. Cunningham, "The Distribution and Growth of Hydrometeors around a Deep Cyclone," Tech. Rep. No. 18, M.I.T. Weather Radar Research, Cambridge, Mass.; May, 1952.
The Air Force Cambridge Research Center maintains an active program in this field. Especially developed radar systems are used particularly for vertical probing through cloud systems and precipitation. Much has been learned about processes initiating precipitation, microwave attenuation due to rain, scattering from cloud particles, and scattering of polarized radiation from nonspherical particles.
(982) D. Atlas and H. C. Banks, "The interpretation of microwave reflections from rainfall," Jour. Met., vol. 8, pp. 271-282; October, 1951.

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(983) V. G. Plank, D. Atlas, and W. H. Paulsen, "Preliminary Survey of Cloud and Precipitation Detectionat 1.25 CM, Proc. Third Radar Weather Conf., McGilUlnmiv., Canada, pp. B1320; September, 1952.
For three years the Air Force has sponsored some of the research in precipitation physics carried on by the Stormy Weather Group at McGill University, which includes extensive studies of the details of microwave scattering from precipitation. Emphasis there was appropriately placed on snow,
(984) J. S. Marshall and K. L. S. Gunn, "Measurement of snow parameters by radar,» Jour. Met., vol. 9, pp. 322-327; October, 1952.
and melting snow that creates the familiar horizontal bright band on range-height indicators.
(985) M. Kerker, P. Langleben, and K. L. S. Gunn, "Scattering of microwaves by a melting, spherical ice particle," Jour. Met., vol. 8, p. 424; December, 1951.

despite the decline of sunspot activity throughout the past five years. Solar outbursts of wavelength less than 1 cm were recorded for the first time during May through September, 1951; four out of the five such bursts detected by Hagen and Hepburn on a wavelength of 8.5 mm occurred in association with flares.
(990) "American astronomers report," Sky and Telescope, vol. 11, pp. 169-171; May, 1952.
(991) R. E. Burgess and C. S. Fowler, "Solar activity and ionospheric effects," Wireless Eng., vol. 29, pp. 46-50; February, 1952.
(992) J. P. Hagen and N. Hepburn, "Solar outbursts at 8.5-mm. wave-length," Nature (London), vol. 170, pp. 244-245; August 9, 1952.
(993) T. Hatanaka and F. Moriyama, "On some features of noise storms," Rep. Ionosphere Res. Japan, vol. 6, pp. 99-109; 1952.
(994) A. Maxwell, "Possible identification of a solar M-region with acoronal region of intense radio emission," Observatory, vol. 72, pp. 22-26; February, 1952.
(995) J. A. Simpson, W. Fonger, and L. Wilcox, "A solar component of the primary cosmic radiation,» Phys. Rev., vol. 85, pp. 366368; January 15, 1952.

The fluctuating character of weather echoes received interesting statistical treatment indicating that even though weather echoes are similar to noise they may be detectable well below noise level by analysis of anumber of return pulses.
(986) W. Hitschfeld, "Detectability of Threshold Echoes," Proc. Third Radar Weather Conf., McGill Univ., Canada, pp. G1518; September, 1952.
The University of Chicago, University of Illinois, and Illinois State Water Survey co-operatively operated a project particularly directed toward measuring rainfall rates by radar. They demonstrated that a properly calibrated radar can measure the rainfall rate over small areas of an acre or two with satisfactory accuracy, or total rainfall over a large area with better accuracy than ordinary rain-gauge networks.
(987) F. A. Huff and G. E. Stout, "Area-depth studies for thunderstorm rainfall in Illinois," Trans. Amer. Geophys. Union, vol. 33, pp. 495-498; August, 1952.
Their program is expanding. Recent work in England and Australia,
(988) J. E. N. Hooper and A. A. Kippax, "The bright band--a phenomenon associated with radar echoes from falling rain," Quart. Jour. R. Met. Soc., pp. 125-132; April, 1950.
(989) E. G. Bowen, "Radar observations of rain and their relation to mechanisms of rain formation,» Jour. Atmos. and Test% Phys., vol. I, pp. 125-140; 1951.
and other groups in the United States, used radar primarily as a meteorological tool for exploration of precipitation processes. Its exceptional value in this field is clearly demonstrated.
Radio Astronomy
Solar Radio Waves. Routine measurements of solar radiations in the radio-frequency band are now being made on approximately adozen wavelengths at various observing stations scattered throughout the world, and both instruments and methods for conducting special investigations have been improved.
Instances of the association of some of the abnormal solar radio emissions with solar and geophysical phenomena of other types (such as flares, sudden ionospheric disturbances, increases of the intensity of primary cosmic rays, and the like) continued to be reported

The annular and total solar eclipses of September 1, 1951 and February 25, 1952, respectively, provided radio astronomers with excellent opportunities for determining the distribution of radio emission as a function of position on the sun's disk. The earlier eclipse was observed on frequencies of 9,350 and 169 mc and the later eclipse on frequencies of 550 and 255 mc by French observers, and on frequencies of 35,000 and approximately 3,000 mc by an expedition from the United States. Observations outside the path of totality of the 1952 eclipse were also made on 169 mc by observers in France and in French West Africa. The sun was relatively "quiet" during both eclipses.
Two conClusions drawn from observation of the 1951 eclipse were 1) on 9,350 mc, the sun's disk shows limb brightening, and 2) the effective diameter of the sun's disk on 169 mc was approximately 1.4 times as great as the optical diameter. Measurements made during the 1952 eclipse confirm that the sun's disk as observed on 169 mc was very much larger than the optical disk, and indicate further that it lacks radial 'symmetry and has the shape of aconsiderably flattened ellipse whose major axis coincides with the equatorial diameter.
(996) J. F. Denisse, E. J. Blum, and J. L. Steinberg, "Radio observations of the solar eclipses of September 1, 1951, and February 25, 1952," Nature (London), vol. 170, pp. 191-192; August 2, 1952.
(997) M. Laffineur, R. Michard, J. C. Pecker, M. d'Azambuja, A. Dollfus, and I. Atanasijevié, "Observations combinées de l'éclipse totale de soleil du 25 février 1952 à Khartoum (Soudan) et de l'éclipse partielle au radio-télescope de l'Observatoire de Meudon," Compt. Rend. (Paris), vol. 234, pp. 15281530; April 7, 1952.
Interferometer techniques continued to be widely used for locating on the solar disk the positions of sources of solar radio emissions. An instrument built at the Commonwealth Scientific and Industrial Research Organization, Australia enabled both the position and polarization of asource to be determined within a time interval of less than a second. With this instrument, the positions of the sources of some thirty noise storms were revealed and six of these studied in detail. The intensity of such astorm appeared to be more closely related to the size of the largest spot in the group of sunspots with which the storm is associated

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Radio Progress During 1952

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than to the size of the group as awhole, and the sense of the circular polarization of the radio emission appeared to be dependent on the polarity of the magnetic field of the associated spot. The rapid motions of the sources of six solar outbursts were followed, and it was found that in the early stages such sources usually tend to move swiftly outward toward, and sometimes even beyond, the solar limb.
(998) A. G. Little and R. Payne-Scott, "The position and movement on the solar disk of sources of radiation at afrequency of 97 mc/s. I. Equipment," Aust. Jour. Sci. Res., ser. A, vol. 4, pp. 489-507; December , 1951.
(999) R. Payne-Scott and A. G. Little, "The position and movement on the solar disk of sources of radiation at afrequency of 97 mc/s. II. Noise storms," Aust. Jour. Sci. Res., ser. A, vol. 4, pp. 508-525; December, 1951.
(1000) R. Payne-Scott and A. G. Little, "The position and movement on the solar disk of sources of radiation at afrequency of 97 mc/s. III. Outbursts," Aust. Jour. Sci. Res., ser. A, vol. 5, pp. 32-46; March, 1952.
The occultation of the radio star in Taurus by the solar corona was observed at Cavendish Laboratory in June, 1952, with an interferometer of large resolving power. The corona was observed to affect the radiation from the radio star even when the angular distance of the radio star from the sun's center was as great as ten times the sun's optical radius.
(1001) K. E. Machin and F. G. Smith, "Occultation of aradio star by the solar corona,» Nature (London), vol. 170, pp. 319-320; August 23, 1952.
The line spectrum of atomic hydrogen was investigated and found to include an absorption line, produced by the 22S112 -22P312 fine-structure transition, which may be observable in the solar spectrum at afrequency
of about 10,000 mc.
(1002) J. P. Wild, "The radio-frequency line spectrum of atomic hydrogen and its applications in astronomy," Astrophys. Jour., vol. 115, pp. 206-221; March, 1952.
Other recent theoretical studies of solar radio emissions dealt primarily with the interpretation of these radiations in terms of plasma oscillations.
(1003) J. F. Denisse and Y. Rocard, "Excitation d'oscillations électroniques dans une onde de choc. Applications radioastronoiniques," Jour. Phys. Rad., vol. 12, pp. 893-899; December, 1951.
(1004) J. Feinstein, "Condition for radiation from a solar plasma,» Phys. Rev., vol. 85, pp. 145-146; January 1, 1952.
(1005) R. Q. Twiss,i"On Bailey's theory of amplifier circularly polarized waves n an ionized medium," Phys. Rev., vol. 84, pp. 448-457; November I, 1951.
(1006) R. Q. Twiss, "Excess radio noise from solar flares and sunspots," Nature (London), vol. 169, pp. 185-186; February 2, 1952.
Galactic Radio Waves. The list of frequencies of observed galactic radio-frequency radiation were considerably extended on the high-frequency side by the successful measurement of such radiation on 255, 1,210, and 3,000 mc per second. Contour lines giving the distribution of the 255-mc radiation over the sky were deduced. The first detailed measurements at afrequency (18.3 mc) near the opposite end of the observable range were also reported, and contour lines showing the distribution of equivalent temperature at this frequency in a zone of the sky centered at declination --34° were derived. The observed temperatures were found to be much higher, and the ratio of maximum to minimum much lower, at 18.3 mc than at 100 mc.

(1007) I. Atanasijevié, "Mesures du rayonnement de la Voie Lactée

sur 255

Comét. Rend. (Paris), vol. 235, pp. 130-132;

July 16, 1952. (1008) J. H. Piddington and H. C. Minnett, "Observations of

galactic radiation at frequencies of 1210 and 3000 mc/s.,"

Aust. Jour. Sci. Res., ser. A, vol. 4, pp. 459-475; December,

1951.

(1009) C. A. Shain, "Galactic radiation at 18.3 mc/s.," Aust. Jour.

Sci. Res., ser. A, vol. 4, pp. 258-267; September, 1951.

Two Australian scientists published the first contours showing the distribution on the sky of a galactic-line emission in the radio spectrum. The emission line in question, which occurs at 1,420 mc and results from a hyperfine-structure transition of hydrogen, was found in certain directions to consist of two components. If the separation is an effect of galactic rotation, as seems reasonable to assume, the measurement of the displacements of the components will yield adetermination of the distances of the sources. A powerful method for the investigation of the structure of the galaxy is therefore suggested.
(1010) W. N. Christiansen and J. V. Hindman, "21 cm line radiation from galactic hydrogen," Observatory, vol. 72, pp. 149-151; August, 1952.

A survey of the southern sky on a frequency of 101 mc revealed the presence of 77 discrete sources of radio emission. Although the more intense of these sources are concentrated toward the galactic equator, the weaker ones tend to be randomly distributed. The number of known discrete sources now exceeds 100. Attempts to identify them as a group with a particular type of astronomical object were unsuccessful, but identifications of a number of individual sources were made. Within the past year, for example, several external galaxies, two clusters of galaxies, and the remnants of Tycho Brahe's supernova of 1,572 were all identified as sources of radio-frequency radiation. Attempts to use an interferometer of high precision for the measurement of parallaxes or proper motions of four of the prominent radio stars yielded negative results.
(1011) R. H. Brown and C. Hazard, "Extra-galactic radio-frequency radiation, » Phil. Mag., vol. 43, pp. 137-152; February, 1952.
(1012) R. H. Brown and C. Hazard, "Radio-frequency radiation from Tycho Brahe's supernova (A.D. I572)," Nature (London), vol. 170, pp. 364-365; August 30, 1952.
(1013) B. Y. Mills, "The distribution of the discrete sources of cosmic radio radiation," Aust. Jour. Sci. Res., ser. A, vol. 5, pp. 266287; June, 1952.
(1014) F. G. Smith, "An attempt to measure the annual parallax or proper motion of four radio stars," Nature, vol. 168, pp. 962963; December 1, 1951.
Among the discrete sources that were recently studied in particular detail are the Andromeda Nebula, the Cygnus radio star, and adiffuse source near the latter. The 158.5-mc radiation from the Andromeda Nebula was observed with a 218-foot paraboloidal antenna whose beam width to half power is only 2° at this frequency. The measured intensity of the radiation agreed well with the intensity predicted on the assumption that the Andromeda Nebula is similar to our galaxy. A prominent discrete source with an angular extent of around 10° was discovered in Cygnus, and spectrum curves for this radio nebula and for the Cygnus radio star were derived from observations on

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half adozen frequencies in the range from 60 to 3,000 mc. The spectrum of the extended source differs from both that of the radio star and that of the general galactic radiation, and the source was tentatively identified with the bright galactic nebulas surrounding 7 Cygni.
(1015) R. H. Brown and C. Hazard, "Radio emission from the Andromeda Nebula," Mon. Not. R. Astr. Soc., vol. 111, pp. 357-367; 1951.
(1016) R. H. Brown and C. Hazard, "A radio survey of the Cygnus region. I. The localized source Cygnus (1)," Mon. Not. R. Astr. Soc., vol. 111, pp. 576-584; 1951.
(1017) J. H. Piddington and H. C. Minnett, "Radio-frequency radiation from the constellation of Cygnus," Aust. four. Sel. Res., ser. A, vol. 5, pp. 17-31; March, 1952.
An analysis of the 100-mc galactic radiation indicated that a single spheroidal source distribution cannot account for the observed intensities in the direction away from the galactic plane.
(1018) J. G. Bolton and K. C. Westfold, "Galactic radiation at radio frequencies. IV. The distribution of radio stars in the galaxy," Aust. Jour. Sci. Res., ser. A, vol. 4, pp. 476-488; December, 1951.
Ionospheric Propagation'
The ionosphere comprises all of the upper atmosphere beyond about 60 km. It is perhaps this simple matter of definition which makes its study so broad in scope and which currently produces several hundred new papers annually.
Radio wave propagation in the ionosphere is dependent upon the physical state of the ionosphere at the particular time and place. Thus the radio engineer must inevitably become concerned with matters which are more properly the concern of the scientist.
It is not an easy matter to describe progress in a categorical and neatly classified way because of the interdependeace of most of the subjects of investigation. Neither is it possible in the space available here to treat a comprehensive list of subjects. However, topics selected from the agenda of Commission 3(ionospheric radio wave propagation), of the Tenth General Assembly of the International Scientific Radio Union (URSI) held in Sydney, Australia, in August, 1952, will serve to point out some of the most significant matters under investigation by leading researchers.
A meeting was held at the National Bureau of Standards in Washington, D. C. in April, 1952, which was jointly sponsored by URSI and the IRE Professional Group on Antennas and Propagation. The papers presented at this meeting were abstracted in the PROCEEDINGS OF THE I.R.E. in June, 1952. The complete proceedings of the meeting, including some nonscheduled papers, are available in the TRANSACTIONS OF THE I.R.E., PGAP-3, in August, 1952, issued by the Professional Group.
2 This account is an abridgement of the paper, M. G. Morgan, "Progress in ionospheric research during 1952."
D.S.I.R. Abstracts refer to those prepared by the Department of Scientific and Industrial Research in London and carried monthly in PROC. I.R.E.
R.I.R.J. Abstracts refer to those carried in Report of Ionospheric Research in Japan (approximately quarterly; in English).

A new edition (second) of S. K. Mitra's book, "The Upper Atmosphere" (The Asiatic Society, 1 Park St., Calcutta), has been published this year. This book is by far the most comprehensive treatment of the subject available. The appearance of the second edition, only five years after the first, is amanifestation of the speed with which our knowledge of the upper atmosphere is increasing.
Movements of the Ionosphere. It is now generally recognized that there exist in the ionosphere, in addition to motions due to tides, motions due to pressure gradients caused by temperature inequalities. In the F region, large-scale movement is certainly profoundly affected by additional forces arising from the motion of the charged particles in the geomagnetic field. D. F. Martyn pointed out at the URSI Assembly that, though the tidal motions are mainly horizontal, the ions and electrons are constrained to move along the terrestrial magnetic lines of force. This motion has, in general, a vertical component except at the equator. This behavior explains many of the known anomalies of the F2 layer and the small but significant departures of the E and F1 regions from the ideal Chapman region. A further consequence of these considerations is that the usual methods of measuring the recombination coefficient from observations of the diurnal variation of ionization need to be modified.
Martyn pointed out that a polarization field is developed by the motion of the charged particles across the magnetic field (Hall effect) and that this also gives rise to vertical drifts of ions and electrons.
(1019) 0. Lindberg, "Hall effect," PROC. I.R.E., vol. 40, pp. 14141419; November, 1952.
There are, in addition, traveling disturbances of smaller scale (the order of afew km) which can be observed as the transit of some characteristic feature of the ionization, such as a hump in the virtual-height versus frequency curve, from one observatory to another. There is the possibility that these may not always represent actual transport of charged particles although recombination rates would have to be very high in some cases if they were not.
The speed and direction of the movements are observed to have diurnal, seasonal, and height dependences. Horizontal velocities are of the order of hundreds of meters per second and vertical velocities of the order of 5.
L. A. Manning has pointed out that "average wind velocity," to be significant, must include adefinition of the domain thickness and the nature of the turbulence. R. Gallet has gone so far as to suggest that the continuing enigma of sporadic ionization in the E region may be accounted for by turbulence wherein fluctuations of atmospheric density produce electron concentration without invoking additional ionization. (See the discussion herein of "sporadic-E ionization" under the section title Miscellaneous.)
The following selected references are about one-

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third of the number which have appeared in the past year on this subject.

(1020) G. J. Phillips "Measurements of winds in the ionosphere,"

Jour. Atmos. Terr. Phys., vol. 2, pp. 141-154; 1952. D.S.I.R.

Abstract 1916.

(1021) R. E. Jones, G. H. Millman, and R. J. Nertney, "Turbulence

in the lower ionosphere as deduced from increments in ab-

sorption and phase path at 150 kc/s," TRANS. I.R.E., PGAP-3,

p. 139; August, 1952. (Abstract.) Also abstracted in PROC.

I.R.E., vol. 40, p. 744 (paper no. 43); June, 1952.

(1022) A. Newish, "The diffraction of galactic radio waves as a

method of investigating the irregular structure of the iono-

sphere," Proc. Roy. Soc. A, vol. 214, pp. 494-514, October,

1952. See also ibidem, vol. 209, pp. 81-96, October, 1951.

D.S.I.R. Abstract 1284. (1023) J. S. Greenhow, "A radio echo method for the investigation of

atmospheric winds at altitudes of 80-100 km," Jour. Atmos.

Terr. Phys., vo.. 2, pp. 282-291; 1952. D.S.I.R. Abstract 3083.

(1024) L. A. Manning, O. G. Villard, Jr., and A. M. Peterson,

R"eDso.u, bvloel.-D5o7pp,lpe.r3s8t7u-d4y04o;f

meteoric echoes," September, 1952.

Jour.

Geophys.

(1025) J. Feinstein, On nature of the decay of a meteor trail,"

Proc. Phys. Soc. B, vol. 65, p. 741; September, 1952. (Cor-

respondence.)

Effective Conductivity of the Ionosphere. At the URSI Assembly, W. G. Baker and D. F. Martyn presented their paper with the above title. They pointed out that the height-integrated conductivity of the ionosphere need not be greater than about 5 to 10X10-9 emu to satisfy the rsquirements of the dynamo theory. The best and most recent study of ionospheric conductivity indicates avalue no greater than about 4.5 X10-9 emu.
(1026) D. R. Bates and H. S. W. Massey, "The negative ion concentration in the lower ionosphere," Jour. Atm9s. Terr. Phys., vol. 2, pp. 1-13; 1951. D.S.I.R. Abstract 983. See also ibidem, pp. 253-254; 1952. (Correspondence.) D.S.I.R. Abstract 2796.

The ionospheric conductivity thus appears to be deficient by afactor of at least 12.
It was shown by Baker and Martyn that the ionosphere, considered as a thin sheet in which vertical currents are prohibited by polarization, has heightintegrated Hall conductivity, at right angles to the electric field, some 3to 3.5 times greater than the direct conductivity. Combining the direct conductivity and the Hall conductivity suitably, they show that the effective conductivity is 5X10-9 as required by the
dynamo theory. Within afew degrees of the magnetic equator, the Hall conductivity diminishes rapidly, but the direct east-west conductivity increases rapidly. This results in an effective conductivity, in a narrow strip at the equator, about 2.4 times that over the rest of the
earth, thus explaining the equatorial enhancement of the daily magnetic variation. Since the current is nearly at right angles to the electric field over most of the earth, but parallel to it at the magnetic equator, the electric field must undergo arapid phase shift of nearly ir/2 within afew degrees of the equator. In this region the current will be centered at 100 km ±10 km, but in higher latitudes should be mainly between 120-150 km.
Essentially the same observations have apparently been made by M. Hirono.
(1027) M. Hirano, "On the influence of the Hall current to the electrical conductivity of the ionosphere," Rep. Ionospheric Res. (Japan), vol. 6, pp. 44-45. Also, under the same title, pt. I, Jour. Geomag. Geoek. (Japan), vol. 2, p. 1; 1950. R.I.R.J. Abstract no. I-1. pt. II, ibidem, vol. 2, P. 113; 1950. R.I.R.J. Abstract no. I-2.

J. A. Ratcliffe has shown that many of the anomalies of F-layer critical frequencies vanish when one considers instead the height-integral of electron density. He and J. M. Kelso have presented different, rapid means of obtaining the true height distribution of electron density from virtual height versus frequency records.
(1028) J. A. Ratcliffe, "Some regularities in the F2-region of the ionosphere," Jour. Geophys. Res., vol. 56, pp. 487-507; December, 1951. D.S.I.R. Abstracts 1294. Also, "A quick method for analyzing ionospheric records," ibidem, pp. 463-485. D.S.I.R. Abstract 1292.
(1029) J. M. Kelso, "A procedure for the determination of the vertical distribution of the electron density in the ionosphere," Jour. Geophys. Res., vol. 57, pp. 357-368; September, 1952.
Ionospheric Storm Phenomena. D. F. Martyn has analyzed ten years of hourly Fs-region virtual height
and critical frequency records taken from selected latitudes. He has found that diurnal disturbance varia-
tions of these quantities exist which closely parallel those of the magnetic field. A correspondence is also found on a "storm-time" scale. Previous theories of these Fs-region disturbances attribute them to bombardment of the region by particles from the sun. Martyn finds such theories invalid and proposes that they are due, like tidal variations, to electric fields in the iono-
sphere. The fields, he believes, are created by the intense current systems in the auroral zones, and are spread over the earth according to Laplace's theorem. Over most of the earth, the drift is such as to raise the average height of the Fs-region, and to spread out its ionization, thus reducing the critical frequency on the average. Near the equator, however, the drift due to the electric field of the magnetic disturbance counteracts that due to the normal "quiet-day" field (refer to preceding discussion on Hall conductivity) and leads on the average to increased critical frequency since it counteracts the normal spreading out of the ionization in the vertical direction. In the early morning, the effect of storms is enormous, since it prevents the Fs-region from falling into the recombination "sink" at about 200 km, and this is generally noted in critical frequency data as the onset of the storm. The Hall conductivity is invoked to account for some six hours phase difference between the phase of the solar diurnal magnetic variation (SD)at the equator and in the auroral zone. The
onset is simultaneous over the world, but is most noticeable at locations where the local time of magnetic storm commencement occurs at the time of steepest slope of
the SDcurve. The effect of a storm lasts about three days, since
this is the time necessary for the Fs-region to settle to "steady-state" variation under the "quiet-day" tidal influence. The early behavior of the critical frequency in "storm-time" depends markedly on the local time of occurrence of the sudden commencement. If the magnetic storm commences at a local time when the SD
versus critical-frequency curve is near its maximum
positive value, the critical frequency is immediately
depressed. If the storm commences at atime when the critical frequency is increasing, the critical frequency is

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PROCEEDINGS OF THE I.R.E.

April

raised. There is no evidence of a time progression of disturbance from the polar zones; disturbance in the F2-region is simultaneous throughout the world. However, the local time effect described may give rise to false impressions of such a progression owing to the time phase change with latitude, ascribed to the Hall conductivity, of the onset. Storms commencing near sunset exhibit only anegative phase (depressed critical frequency) whereas those commencing near sunrise exhibit first a positive phase (enhanced critical frequency) and then a negative phase in a day or so. In general, storms cause atendency towards summer conditions and amplified tidal oscillations.
This model of ionospheric storms was presented by Martyn at the URSI Assembly in Australia and represents the progress in his thinking since the presentation of his theory of magnetic storms and auroras at the URSI Assembly in Zurich in 1950 and reported last year in these pages.
(1030) D. F. Martyn, "The theory of magnetic storms and auroras," Nagure, vol. 167, p. 92; January, 1951. See also the note, T. Nagata, "On the position of the auroral zone," Rep. Ionospheric Res. (Japan), vol. 6, pp. 159-161; September, 1952.
Although not yet assured of survival, Martyn's thoughts on magnetic storms, auroras, and ionospheric storms are some of the best ideas available today.
J. H. Meek has analyzed data from Canadian and other high latitude stations and found that disturbances appear first in one part of the auroral zone and then move around the earth with the sun for several days. Maximum depressions (of F2 critical frequency) occur in the southern part of the auroral zone at 60 to 65° N geomagnetic latitude. Absorption is very high in the auroral zone and extends southward in amanner similar to the geographical distribution of critical frequency depression. Blackouts usually come during the morning hours, but in severe disturbances may be effective continuously for several days. Few occur during winter.
(1031) J. H. Meek, "Ionospheric disturbances in Canada," Jour. Geophys. Res., vol. 57, pp. 177-190; June, 1952. D.S.I.R. Abstract 2805.
R. Lindquist has studied polar blackouts in Sweden and finds strong correlation with magnetic measurements, the aurora, and atype of sporadic-E designated N1.Lindquist finds atendency for blackouts to reappear at the same time for two or more days.

The ionospheric prediction services of a number of countries are issuing routine storm warnings with increasing success. The warnings are based upon the observations of co-operating solar observatories. The problem of learning what solar events produce geomagnetic and ionospheric storms is one of the challenging frontiers of solar physics.
Radio Propagation by Scattering. An account of the propagation of vhf signals by scattering from the regular ionosphere, as described in these pages last year, has been published by the authors of that work.
(1033) D. K. Bailey, R. Bateman, L. V. Berkner, H. G. Booker, G. F. Montgomery, E. M. Purcell, W. W. Salisbury, and J. B. Wiesner, "A new kind of radio propagation at very high frequencies observable over long distances," Phys. Rev., vol. 86, pp. 141-145; April 15, 1952.
J. C. W. Scott stated at the URSI Assembly that steady backscatter is obtained from the ionosphere at Saskatoon from 100-km height at 50 mc and 400-km range. It is not seen at 100 mc. Investigators at Cornell University are now completing instrumentation intended to detect vertical backscatter of vhf.
Long-distance backscatter of hf has received agreat impetus now that it is realized that detectable signals can be obtained with low power (hundreds of watts) by using pulses of the order of milliseconds. The usefulness of such experiments is also greatly enhanced by the discovery that the backscatter is almost entirely from the ground, via the ionosphere, and not from the ionosphere itself. It is a surprising fact that there is negligible difference in the effectiveness of ground and water as scattering regions. There appears to be every likelihood that this technique will greatly augment vertical incidence measurements in oblique path-propagation evaluation.
(1034) W. G. Abel and L. C. Edwards, "The source of long distance backscatter," PROC. I.R.E., vol. 39, pp. 1538-1541; December, 1951. D.S.I.R. Abstract 1082.
(1035) J. T. deBettencourt, "Instantaneous prediction of ionospheric transmission circuits by the communication zone indicator (COZI )," TRANS. I.R.E., PGAP-3, pp. 202-209; August, 1952.
(1036) 0. G. Villard, Jr. and A. M. Peterson, "Scatter-sounding: A technique for study of the ionosphere at adistance," TRANS. I.R.E., PGAP-3, pp. 186-201; August, 1952. Abstracted in PROC. I.R.E., vol. 40, p. 746 (paper no. 57); June, 1952. Also, "Instantaneous prediction of radio transmission paths," QS7-,vol. 36, pp. 11-19; March, 1952. Also, "Scatter-sounding: A new technique in ionospheric research," Science, vol. 116, pp. 221-224; August 29, 1952.

(1032) R. Lindquist, "Polar blackouts recorded at the Kiruna observatory," Ada. Pole. (Stockholm), no. 85, 25 pp.; 1951. D.S.I.R. Abstract 783.
The Japanese have been particularly active in the matter of investigating ionospheric storm phenomena. It is not considered necessary to review their work in detail here because of the agreement for the most part with the preceding account. However, the reader who is interested in delving further into this subject will want to review the Japanese literature, including their documents which were transmitted in considerable number to the URSI Assembly in Australia.

The aurora will reflect vhf radio signals. Its irregular and changing nature constitutes a somewhat unusual scattering medium. The quality of radio signals reflected from the aurora is poor, and K. L. Bowles has found the power-spectrum of the fading to have frequency components of roughly equal strength from zero to acut-off frequency of 100 to 200 c.
(1037) R. K. Moore, "Theory of radio scattering from the aurora," TRANS. I.R.E., PGAP-3, pp. 217-229; August, 1952. Abstracted in PROC. I.R.E., vol. 40, p. 747 (paper no. 65); June, 1952.
(1038) K. Bowles, "The fading rate of ionospheric reflections from the aurora borealis at 50 mc/s," Jour. Geophys. Res., vol. 57, pp. 191-196; June, 1952. D.S.I.R. Abstract 2876.

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LF and VLF Ionospheric Propagation. There has been further reporting on the extensive oblique path program of investigation on these frequencies at the Cavendish Laboratory at Cambridge University.
In passing from the range 90-200 km, to 535 km, at 16 kc, the following facts are noted:
1. At short distances the reflection coefficient is about 0.15 by day and 0.50 at night in summer; the corresponding values at 535 km are 0.3 and 0.55.
2. At distances from 90 to 535 km the waves are reflected from an apparent height of about 74 km at midday and about 92 km at night. The way in which the height varies with the inclination of the sun's rays is markedly different for the two paths.
3. At 535 km, sid produces alower reflection height but little change in amplitude of the downcoming wave. During and after severe magnetic storms the diurnal variation of the signal amplitude is abnormal, the abnormality persisting for as long as 38 days.
At 70-128 kc, significant changes are also noted in passing to longer distances. Information is available at 100 km and from 350-950 km and the following facts are noted:
1. At 100 km the absorption shows marked solar control, increasing about one hour before ground sunrise. At greater distances, the reflection coefficient is found to increase steadily with distance. At midday in summer on 70 kc it is found to be 0.02 at 300 km and 0.09 at 800 km. It is found to be less on higher frequencies, and in winter the values are roughly doubled.
2. At 100-km range, the apparent height of reflection on asummer day is about 70 km. It increases, on the average, 7-8 km from day to night. The change commences at about ground sunrise rather than an hour before as with absorption. Results at 350-km range were nearly identical, but at 850-950-km range it was found that both the absorption and apparent height change about one hour before ground sunrise at the midpoint of the path. The daytime apparent height of reflection is 70 km as for the shorter ranges, but the increase at night is of the order of 20 km.
3. At 100 km, the effect of sid is to reduce the amplitude of the sky wave by a factor of about 0.01 and to decrease the apparent height by as much as 10 km. At 850-950 km, sid causes the amplitude of the sky wave to increase by as much as five times and sometimes to reach its nighttime value.
(1039) R. N. Bracewell, "The ionospheric propagation of radio waves of frequency 16 kc/s over distances of about 200 km," Prot. IEE (London), vol. 99, pt. IV, pp. 217-228; July, 1952. D.S.I.R. Abstract 2870.
(1040) W. C. Bain, R. N. Bracewell, T. W. Straker, and C. H. Westcott, "The ionospheric propagation of radio waves of frequency 16 kc/s over distances of about 540 km," Prot. IRE (London), vol. 99, pt. IV, pp. 250-259; July, 1952. D.S.I.R. Abstracts 2871.
(1041) K. Weekes and R. D. Stuart, "The ionospheric propagation of radio waves with frequencies near 100 kc/s over short distances," Prot. IRE (London), vol. 99, pt. IV, pp. 29-37; April, 1952. D.S.I.R. Abstract 3533.
(1042) K. Weekes and R. D. Stuart, "The ionospheric propagation of radio waves with frequencies near 100 kc/s over distances up to 1000 km," Proc. IEE (London), vol. 99, pt. IV, pp. 38-46; April, 1952. D.S.I.R. Abstract 3534.

The construction of a sweep-frequency recorder covering the range 50-1,000 kc has been described and sample records taken. Results so far have been good throughout most of the frequency range at night, but daytime records are not complete, especially in the summer months.
(1043) J. C. Blair, J. N. Brown, and J. M. Watts, "A sweep fre-
quency ionosphere recorder for the low frequencies," TRANS. I.R.E., PGAP-3, p. 185; August, 1952. (Abstract.) Also abstracted in PROC. I.R.E., vol. 40, pp. 745-746 (paper no. 56); June, 1952.
J. A. Pierce has completed what will surely be amost valuable document for the radio-propagation engineer. The chapter titles are perhaps the most effective way of conveying the nature of this report. They are: (1) the unabsorbed intensity of asingle sky-wave component; (2) the unabsorbed intensity of all possible sky-wave components; (3) transmission losses; (4) observations of low-frequency field strength in 1951; and (5) noise, signal-to-noise ratio, and required power.
(1044) J. A. Pierce, "Sky-Wave Field Intensity: (I) Low and Very Low Radio Frequencies," Tech. Rpt. No. 158, Cruft Laboratory, Harvard University, Cambridge, Mass.; September 1, 1952.
Miscellaneous. It will be expedient to discuss anumber of remaining matters under this title.
The nature and cause of the "sporadic-E" effect still go largely unanswered. As mentioned under Movements of the Ionosphere, R. Gallet has made the interesting suggestion that it can be accounted- for entirely by turbulence and not through the agency of additional ionization.
(1045) R. Gallet, "The nature of the sporadic-E layer and turbulence in the upper atmosphere," Comin. Rend. Acad. Sci. (Paris), vol. 233, pp. 1649-1650; December 19, 1951. D.S.I.R. Abstract 1912.
Two authors have published attempted correlations with the aurora, but the correlations are not strong and the two papers are somewhat contradictory. (However, Lindquist finds correlation of polar blackouts with aurora and acertain type of sporadic-E. Thus acorrelation of this type of sporadic-E with aurora may be inferred. See section on Ionospheric Storm Phenomena.) A correlation of the motion of sporadic-E clouds with geomagnetic variations has also been discussed. It has been pointed out that the new hf backscatter technique provides an excellent method of tracking sporadic-E clouds. (See discussion herein under section title Radio Propagation by Scattering.) K. Rawer and others have published papers on high-frequency absorption. Measurements on different frequencies reveal an important contribution to selective absorption occurring in the E-layer which can be calculated by assuming a parabolic distribution of electron density and an exponential variation of collisional frequency. A graphical method is described which gives the separate contributions of the E- and D-layers. The values of D-layer absorption are lower than those obtained by the usual method in which E-layer absorption is neglected. The E-layer contribution is fairly constant. It is concluded that the E-layer

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April

collisional frequency is certainly less than 104/s, avalue in agreement with recent temperature and pressure data at 125 km. In another paper, collisional frequencies were deduced in the conventional way using the observed diminution of multiple echoes. For the F-layer, measurements were made at four frequencies at night for about six months. For the E-layer, measurements were made at five frequencies at midday for two years. Values of 2X102/s and 6-7 X 103/s were obtained for the collisional frequencies at the middle of the F- and E-regions, respectively.
(1046) K. Bibi and K. Rawer, "The contributions of the D- and Eregions in measurements of ionospheric absorption," J. Atmos. Terr. Phys., vol. 2, pp. 51-65; 1951. (In French.) D.S.I.R. Abstract 985.
(1047) K. Rawer, K. Bibi, and E. Argence, "Determination of the number of collisions in the ionosphere E- and F-regions," Comp. Rend. Acad. Sci. (Paris), vol. 233, pp. 667-669; September 17,1951. D.S.I.R. Abstract 987.
H. W. Wells reported F-region effects of the solar eclipse observed at sunrise on September 1, 1951 with three high-speed recorders on an east-west line 12 minutes apart in local time. He concludes that from the moment when two-thirds of the sun was covered, through the maximum phase (94 per cent), and until one-third of the sun was uncovered, no ionization was produced.
(1048) H. W. Wells, "Ionospheric effects of solar eclipse at sunrise, 1September 1951," Jour. Geophys. Res., vol. 57, pp. 291-304; June, 1952. D.S.I.R. Abstract 2800. See also: "F-region effects of solar eclipse at sunrise, ISeptember 1951," TRANS. I.R.E., PGAP-3, p. 210; August, 1952. (Abstract.) Also abstracted in PROC. I.R.E., vol. 40, P. 746 (paper no. 58); June, 1952.
Oblique path pulses experiments have been described. Several of these are now on asweep-frequency basis. So far, no particularly unexpected results have been reported. The importance of the "high ray" is apparent.
(1049) W. Dieminger, "Echo sounding of the ionosphere at oblique incidence," Z. Angelo. Phys., vol. 3, pp. 90-96; March/April, 1951. D.S.I.R. Abstract 674.
(1050) M. Mayumida, C. Ouchi, and T. Yoshida, "Sweep frequency pulse test of oblique incidence," Proc. Semi-Annual Meet. Central Radio Wave Obs. (Japan), no. 2, P. 128; 1951. R.I.R.J. Abstract no. R-9.
(1051) R. Silberstein, "Interpretation of high-frequency cw fieldintensity records with the aid of simultaneous pulse data," PROC. I.R.E., vol. 40, pp. 974-976; August, 1952. D.S.I.R. Abstract 3219.
(1052) P. G. Sulzer and E. E. Ferguson, "Sweep-frequency obliqueincidence ionosphere measurements over a 1150 km path," PROC. I.R.E. (Correspondence), vol. 40, p. 1124; September, 1952. D.S.I.R. Abstract 3530.
The suppression of magneto-ionic rays by transmitter polarization control has been investigated further and attenuations of as much as 50 db obtained. The statistical nature of the fading of asingle magneto-ionic component at oblique incidence has been investigated and found to be log-normal in character.
(1053) M. G. Morgan, "Polarization control and measurement in ionosphere vertical incidence echo ranging," TRANS. I.R.E., PGAP-3, pp. 33-41; August, 1952. Abstract in PROC. I.R.E., vol. 40, P. 740 (paper no. 14); June, 1952.
(1054) H. P. Hutchinson, "Short period sky-wave fading of cw emissions," TRANS. I.R.E., PGAP-3, pp. 12-18; August, 1952. Abstracted in PROC. I.R.E., vol. 40, p. 739 (paper no. 11);

June, 1952. Also presented at I.R.E. Western Electronic Show and Convention, Long Beach, California; August 26-29, 1952.
An outline of the effects of all the layers in calculating received hf field strength, going somewhat beyond present methods, has been presented.
(1055) K. Rawer, "A calculation method for sky-wave field strength," PROC. I.R.E., vol. 40, P. 973; August, 1952. (Abstract.) The full paper has been published as "Calculation of sky-wave field strength," Wireless Engr., vol. 29, pp. 287-301; November, 1952. D.S.I.R. Abstract 199.
J. C. W. Scott has presented much needed information on solar control of the E- and Fs-layers at high latitudes. He finds that, whereas both follow the Chapman law, the sensitivity of the E-layer to solar angle is very small in the auroral zone. It recovers north of the zone. The Fi-layer is found to have rather low sensitivity at all latitudes.
(1056) J. C. W. Scott, "The solar control of the E- and Fl-layers at high latitudes," Jour. Geophys. Res., vol. 57, pp. 369-386; September, 1952.
C. M. Minnis has discussed the longitude effect found in Fs-region parameters and suggests that prediction services use aset of hourly charts each of which would show the distribution at afixed value of zero meridian time.
(1057) C. M. Minnis, "The graphical representation of the longitude effect in F2-region," J. Atmos. Terr. Phys., vol. 2, pp. 261265; 1952. D.S.I.R. Abstract 3081.
Conclusion. The references in the foregoing account represent about 15 per cent of those which have appeared on ionospheric matters in the literature of the free world in the past twelve months, not to mention approximately one hundred Commission 3 documents transmitted to the URSI Assembly in Australia. Mitra's book, whose text is of great value, is of at least equal value as a key to the great mass of accumulated periodical literature.
Designers and operators of communication circuits utilizing ionospherically propagated signals will find the new book "Radio Spectrum Conservation" (McGrawHill Book Co., Inc., New York, N. Y.) of very considerable value. This book, published in May, 1952 was prepared by the Joint Technical Advisory Committee under the sponsorship of IRE and RTMA. Nearly half of it consists of Chapter 2, entitled "Propagation Characteristics of the Radio Spectrum." It was prepared as follows: Sec. 1, General, J. H. Dellinger; Sec. 2, 10-200 kc/s, (Mrs.) M. L. Phillips; Sec. 3, 0.2-2 mc/s, W. S. Duttera; Sec. 4, 2-30 mc/s, T. N. Gautier; Sec. 5, 30-3000 mc/s, C. R. Burrows; and Sec. 6, 3-300 kmcls, G. C. Southworth.
Acknowledgment
The individual sections of this report were prepared by the Technical Committees of the IRE, who made assignments to individuals or groups to carry on the investigations necessary to make acomprehensive review of the particular field of activity assigned to them.

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These reporters are thanked for their diligence in this preparation. All of the reports were reviewed by the members of the Annual Review Committee Editorial Board, and the reports correlated as to style and content. The membership of this Editorial Board and the names of the engineers who prepared the sections of the report follow:

R. R. Batcher, Chairman T. H. Clark J. D. Crawford R. T. Hamlett

S. W. Harrison H. P. Westman L. E. Whittemore E. K. Gannett, Consultant

Electron Tubes and Semiconductors: S. W. Harrison, G. D. O'Neill, C. E. Fay, H. L. Thorson, G. A. Espersen, J. J. Henry, R. M. Ryder, W. H. Hall, F. S. Veith, and R. B. Jones.
Feedback-Control Systems: R. J. Kochenburger. Audio Techniques: W. L. Black. Sound Recording and Reproducing: S. Fairchild. Electroacoustics: H. C. Hardy.

Information Theory and Modulation Systems: E. R. Kretzmer. Circuit Theory: W. R. Bennett, R. L. Dietzold, J. G. Linvill, W. A.
Lynch, and C. F. Rehberg. Radio Transmitters: P. J. Herbst, A. E. Kerwien, M. R. Briggs, and
I. R. Weir. Receivers: L. M. Harris. Video Techniques: A. J. Baracket. Television Systems: S. Heft, J. Veatch, W. B. Whalley, W. H. Sahloff,
C. Spicer, G. R. Tingley, H. C. Milholland, J. B. Coleman, L. R. Fink and S. Applebaum. Facsimile: J. H. Hackenberg. Vehicular Communications: D. Tolley. Navigation Aids: H. R. Mimno. Wave Propagation: H. Wells, T. J. Carroll, M. G. Morgan, and M. S. Carpenter. Antennas Waveguides: John Ruze. Servosystems: R. J. Kochenburger. Industrial Electronics: C. F. Spitzer, C. A. Rosen, and R. C. Barker. Electronic Computers:. D. R. Brown. Measurements and Instrumentation: P. S. Christaldi, J. L. DaIke, H. E. Dinger, G. L. Fredendall, W. D. George, R. W. Lowman, W. J. Mayo-Wells, G. A. Morton, G. D. Owens, A. P. G. Peterson, J. G. Reid, Jr., and J. R. Steen.

CORRECTION
Olof Lindberg, author of the paper, "Hall Effect," which appeared in the November, 1952 issue of the PROCEEDINGS OF THE I.R.E., has brought the following error to the attention of the editors:
On page 1419, column 1, the second equation following the first paragraph should read,
VN = B sin 6.124
and not = B sin We.

508

PROCEEDINGS OF THE I.R.E.

April

Standards on Sound Recording and Reproducing: Methods of Measurement of Noise, 1953*

J. Avins R. R. Batcher J. G. Brainerd M. R. Briggs F. T. Budelman C. A. Cady P. S. Carter A. G. Clavier J. L. Dalke A. W. Friend

COMMITTEE PERSONNEL

Standards Committee, 1952-1953

A. G. JENsEN, Chairman M. W. BALDWIN, JR., Vice Chairman L. G. CUMMING, Vice Chairman E. WEBER, Vice Chairman

F. J. Gaffney W. D. Goodale, Jr. R. A. Hackbusch J. G. Kreer, Jr. E. A. Laport G. D. O'Neill C. H. Page W. M. Pease W. J. Poch A. F. Pomeroy

D. C. Ports P. C. Sandretto R. Serrell R. F. Shea R. E. Shelby N. Smith R. A. Sykes W. G. Tuller J. P. Veatch R. J. Wise

S. J. Begun M. S. Corrington S. M. Fairchild R. M. Fraser G. Graham G. P. Hixenbaugh

Sound Recording and Reproducing Committee, 1950-1953

A. W. FRIEND, Chairman H. E. ROYS, Past Chairman L. THOMPSON, Vice Chairman

F. L. Hopper E. W. Kellogg C. J. Lebel R. A. Lynn J. Z. Menard E. Miller
A. R. Morgan

A. P. G. Peterson H. Schecter R. A. Schlegel W. Shepard, Jr. C. F. West R. E. Zenner

D. R. Andrews W. H. Erikson G. Graham

Subcommittee on Magnetic Recording

A. P. G. PETERSON, Chairman A. W. FRIEND, Past Chairman

J. Z. Menard J. H. McGuigan W. Shepard, Jr.

W. W. Wetzel R. E. Zenner

1. INTRODUCTION
1.1 General Description
Noise is alimiting factor in any system which stores information because it limits the signal-to-noise ratio and hence the total quantity of stored data. This applies in the field of sound recording and reproducing, as well as in any information storage system.

1.2.1 Noise

1.2 Definitions

As applied to asound recording and reproducing system, any output power which tends to interfere with the utilization of the applied signals except for output signals which consist of harmonics and subharmonics of the input signals, intermodulation products, and flutter or wow.

*Reprints of this Standard, 53 IRE 19 SI, may be purchased while available from The Institute of Radio Engineers, 1East 79 Street, New York 21, N. Y., at $0.50 per copy. A 20 per cent discount will be allowed for 100 or more copies mailed to one address.

1953

Standards on Sound Recording: Measurement of Noise, 1953

509

1.2.2 Spectral-Noise Density

1.2.8 Modulation Noise

The limit of the ratio of the noise output within a specified frequency interval to the frequency interval, as that interval approaches zero.
Note--This is approximately the total noise within a narrow frequency band divided by that bandwidth in cycles per second.
1.2.3 System Noise
The noise output which arises within or is generated by the system or any of its components, including the medium.

Noise which exists only in the presence of asignal and is a function of the instantaneous amplitude of the recorded signal. (The signal is not to be included as part of the noise.)
Note--This type of noise results from such characteristics of arecording medium as light transmission in a film, slope of agroove, magnetism in awire or tape, etc.
1.2.9 Signal-to-Noise Ratio
The ratio of the signal power output to the noise power in the entire pass band.

1.2.4 Equipment Noise
That noise output which is contributed by the elements of the equipment during recording and reproduc-

1.2.9.1 Single-Frequency Signal-to-Noise Ratio
The ratio of the single-frequency signal power output to the noise power in the entire pass band.

ing, excluding the recording medium, when the equip- 2. BASIC METHODS OF MEASUREMENT

ment is in normal operation. Equipment noise usually comprises hum, rumble, tube noise, and component noise

2.1 Noise
The noise from any source is the noise output power as measured by any power meter which correctly loads

1.2.5 The Zero-Modulation State of aRecording Medium
The state of complete preparation for playback in a particular system except for omission of the recording signal.
Note 1--Magnetic recording media are considered to be in the zero-modulation state when they have been subjected to the normal erase, bias and duplication printing fields characteristic of the particular system with no recording signal applied.
Note 2--Mechanical recording media are considered to be in the zero-modulation state when they have been recorded upon and processed in the customary specified manner to form the groove with no recording signal applied.

the source and which is effective throughout the specified range of frequencies. Any voltmeter or ammeter which indicates correct root-mean-square values may be used in combination with the correct load termination resistor in lieu of a wattmeter. Wave filters should be used, as required, to limit the measured noise to aspecified spectral band and to eliminate spurious signals not considered as noise.
Note--At this time the industry is largely equipped with meters which are rated as average reading voltmeters. The apparent power computed from the indicated voltage of a full-wave rectifying meter may be used in lieu of the true rms voltage if the meter type or characteristic is specified.

Note 3--Optical recording media are considered to be

2.2 Spectral-Noise Density

·

in the zero-modulation state when all normal processes of recording and processing, including duplication, have been performed in the customary specified manner, but with no modulation input to the light modulator.

This measurement is adetermination of the spectral distribution of the noise power as a function of frequency. The noise power accepted by a measuring device of narrow bandwidth (a wave analyzer, for instance)

1.2.6 Medium Noise
That noise which can be specifically ascribed to the medium.

is plotted as a function of frequency, in terms of the power per cps. It is necessary to omit from such plots any noise, such as that derived from hum pickup, which is in the nature of discrete spectral lines of bandwidth

1.2.7 Zero-Modulation Medium Noise

less than that of the wave analyzer. Such responses must be plotted strictly as spectral lines of indicated

That noise which is developed in the scanning or re- amplitude.

producing device during the reproducing process when amedium is scanned in the zero-modulation state.

2.2.1 Weighted Spectral-Noise Density

Note--For example, zero-modulation medium noise

The spectral-noise density data may be weighted in

is produced in magnetic recording by undesired varia- relative importance as afunction of frequency to con-

tions of the magnetomotive force in the medium, which form with experimental curves obtained by measure-

are applied across the scanning gap of ademagnetized ments of human-hearing characteristics, if it is desired

head, when the medium moves with the desired motion to relate the data to the hearing characteristic.

relative to the scanning device. Medium noise can be ascribed to nonuniformities of the magnetic properties,

2.2.2 Photographic Recording of Noise

and to other physical and dimensional properties of the

It is also possible to record photographically either

medium.

the instantaneous noise voltage or current amplitude

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Aprt/

versus time from the face of acathode-ray tube with a phosphor of appropriately rapid light-amplitude decay time. A strip of the resultant record lends itself to analysis in terms of transient functions and noise amplitude probability.
2.3 System Noise
It is desirable to determine the noise of a complete system' in one or more ways that indicate the objective and subjective performance of the system. In general high-frequency noise components and low-frequency hum from power-supply equipment constitute the most objectionable portions of the noise. Therefore, measurements should be made to evaluate these two noise sources separately. Weighted measurements which are based upon the sensitivity characteristic of the ear, as a function of frequency, may also be valuable, as stated in Section 2.2.1.
The noise levels of magnetic recording and reproducing systems are in general much lower than those of other recording systems. The difficulties encountered in attempting to measure the true noise level are therefore considerably greater.
It should be noted that in magnetic recording and reproducing systems, care should be exercised in the elimination of the magneto-strictive introduction of mechanical noise into the reproducing system. Mechanical damping of the core structure of the reproducing head, and design to allow smooth, quiet, passage of the record medium over the pole pieces may usually be done sufficiently well to allow one to neglect these effects.
The objective over-all performance of a system requires a noise measurement over the entire specified frequency range of the system. Several different types of noise measurements are possible.
The system noise measurements should be made with the entire system in operation, in accordance with either Section 2.1 or 2.2, or both.
2.4 Equipment Noise
The measurement of equipment noise poses some special problems. In general, it is necessary to consider all noise components introduced during recording and reproducing. An appropriate and quite simple method, from which the over-all process may be evaluated, involves the measurement of the output noise with the motion of the medium arrested. A necessary assumption for the success of this procedure is that the noise introduced in the recording system is negligible in comparison with that introduced in the reproducing system. This may be tested by operating the entire system in the normal recording condition, with the recording medium in motion, but with no input signal applied, and intermittently turning on and off all the apparatus associated with the recording amplifier. 2 If there is no ap-
1 It is necessary that the apparatus to be included in the "system" be specified.
1 In magnetic recording, sources of bias and erase current and their power supplies are considered as parts of the associated apparatus. Switching transients must be minimized and readings taken when their effects are not present.

parent difference between the noise levels of the reproduced signal under the two conditions, when the medium is in astate equivalent to its zero-modulation condition, then it is safe to assume that the recorded noise may be neglected. This condition is fulfilled by many well-designed recording systems.
Under these conditions, the noise from the playback portion of the equipment may be considered to be the noise of the entire equipment. It is that output signal which is produced when the entire system (recording and playback) is excited in the normal playback condition, but with no recording input signal applied and with the recording medium removed from proximity to the reproducing device. The latter condition may be fulfilled by simply removing the recording medium and running the drive mechanism in the normal fashion. In mechanical recording the reproducing device is maintained in contact with an unmodulated groove. A lowpass filter is inserted to allow rumble measurements to be made.
The equipment output noise should be measured by noise power indicating apparatus as stated in Section 2.1 and 2.2. It may be analyzed as in Section 2.3.
2.5 The Zero-Modulation State of aRecording Medium
This condition, as defined, requires no measurement other than azero-reading of the recording signal, except that in magnetic recording the bias condition must be measured as for anormal recording operation.
2.6 Medium Noise
The definitions divide medium noise into two separate categories, Section 1.2.7 (Zero-Modulation Medium Noise) and Section 1.2.8 (Modulation Noise), the second of which depends upon the presence of amodulation signal. It is best to consider these effects separately. At the present time there appears to be no reliable method by which the noise of the medium can be accurately measured, unless the medium noise exceeds the equipment noise. If the equipment noise is sufficiently low, it is possible to measure the system noise and the equipment noise, and then to compute from these values the equivalent medium noise.
2.7 Zero-Modulation Medium Noise
There are major reasons why this noise cannot always be measured reliably. First, the noise voltages generated in the reproducing device can be, in some instances, of such small magnitude that available measuring equipment has sufficient intrinsic noise to make the readings ambiguous. Second, the measured medium noise is so closely related to the operating characteristics of the scanning device that all measurements must be evaluated in terms of the specific geometrical and physical conditions of the reproducing (playback) device. Third, in mechanical recording and reproducing, it is difficult to secure rumble-free test records.
It is possible to produce astandard precision mediumscanning device which has superior characteristics, and

1953

Standards on Sound Recording: Measurement of Noise, 1953

511

which may be used as areference for the comparison of all available types of recording media of essentially equivalent geometrical configuration. It seems wise at this time, however, to delay the fixing of such standards until additional work has been done, so that there is assurance that the standard will not suffer early obsolescence. In the interim one may choose a temporary standard for his personal tests, so that tentative relative comparisons of media may be made. If this procedure is followed, and if the output noise power from the reproducing or playback system with the medium in place and in normal relative motion is somewhat greater than the output-noise power from the same system, with the medium either removed or by-passing the reproducing device, then it is possible to compute the zero-modulation medium noise as the difference between the two noise powers. If desired, the noise spectrum of the medium may be plotted as the difference between the system and the equipment noise spectra. In either instance it seems advantageous to measure or to convert the final values for statement as terminal voltages at the output of the scanning device. The reactance parameters of this scanning device must be of known value and so related that either the electrical resonance effect is negligible or its effects are accountable.
In amagnetic recording system part of the zero-modulation medium noise may result from the application of erase or bias signals containing dc or even-number harmonic components which cause asymmetry of the erase or bias waveforms and which cannot be neglected.
2.8 Modulation Noise
The modulation noise introduced by certain recording media is of sufficient relative amplitude to make its presence easily detectable by ear in the acoustic output derived from awell-designed system. Nevertheless, when measurements are attempted it is found that anumber of difficulties are encountered. The modulation noise intensity is found to be afunction of the amplitude of the recorded signal and to exist, by definition, only in the presence of that signal. Therefore, it is necessary to separate the output signal from the modulation noise without affecting that noise, in order that one may make a measurement of only the noise. A series of sharply-tuned filter devices (of bandwidth consistent with the flutter and wow of the system) seems to be indicated for removal of the fundamental frequency and its important harmonics. Extremely narrow band-rejection filters are needed for this measurement because there is apossibility that the noise may be concentrated within the spectrum which is closely adjacent to the frequencies of the causative modulating signals. These conditions impose additional difficulties in their requirements of extremely accurate regulation of the speed of the medium as it passes the scanning device.
3. MEASUREMENT PROCEDURE
3.1 Noise
System and equipment noise and signals should be measured in the correctly terminated output circuit of

the equipment. For measuring noise which has considerable fluctuations, it is recommended that the meter shall have approximately the dynamic characteristics of the standard vu meter. This meter may be used to measure the noise voltage across the terminating load
resistor. If the noise fluctuations are small, it is desirable to measure the noise power directly by means of any
reliable thermal-type power indicating meter (thermocouple, hot wire, bolometer, or certain vacuum tube devices, for instance) which provides the correct output termination.
The calibration of the measuring equipment should be sufficiently accurate throughout the useful pass band of the system or equipment to be measured so that the specified accuracy of the result may be assured. Beyond
the frequency limits of the pass band the sensitivity of the meter may be cut off as required to suppress the pickup of undesired signals, but in a manner which avoids introduction of undesirable transient effects.
Note--See note after 2.1.

3.2 Broadband Noise Measurements
3.2.1. System Noise Measurements
The recording portion of the system may be improved rather easily to an extent sufficient to prevent the introduction of detectable recorded noise from this source. It is, therefore, to be assumed that the recording signal channel is free from noise which may be recorded at any level above that of the medium noise. It is also to be assumed that in magnetic recording the erase and bias current waves are symmetrical about the axis of zero current, within less than 0.5 per cent, so that excessive medium noise will not be caused by the resultant effective recorded unbalanced dc components.
The recording medium is to be passed through the normal recording processes, with zero recording signal and correct input termination, and then reproduced in the usual way. The output terminals of the reproducing (or playback) system are connected to the correct terminating load resistance (R), and the true rms current (I) which passes through that resistor is indicated or recorded by athermal ammeter or other equivalent device. The noise power output (P) may be computed from the relation

P = PR.

(1)

As an optional method, it is permissible to measure the true rms voltage (E) across the load resistor (R) and to compute the power output from the relation

P = E2/R.

(2)

Another satisfactory method involves the use of a bolometer device of the correct terminating resistance (R) in which the output noise power is dissipated and compared with an adjustable indicated power dissipated from asource of metered dc or sinusoidal ac energy. Any of these devices may be calibrated in combination with the load resistor to indicate power or to indicate decibels with respect to 1mw (dbm).

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PROCEEDINGS OF THE I.R.E.

April

After the noise power output has been measured, the maximum signal output may be measured by applying an input signal which produces not more than the maximum allowable distortion, at any specified frequency, and making a measurement of the output signal level by aprocedure similar to that employed in making the noise measurement. The signal-to-noise ratio of the system may be computed in accordance with the definition
1.2.9.

3.2.2. Equipment Noise Measurement
The equipment noise is measured by removing the recording medium and repeating the system noise measurement with all portions of the equipment activated in the normal manner, so that the adjustments are the same as those used for the system noise measurement.

3.2.3. Medium Noise Computation
The equipment noise power output (P..) measured in accordance with Section 3.2.2 is subtracted from the system noise power output (P..) measured under the same conditions. The result is the medium noise power output (Pmn). Thus,

Pm,, = Pan -- Pen.

(3 )

Subtraction of the total noise power output of the system (P..) from (P.,), the power of the combined specified single-frequency-signal and noise, yields (P,,,,), the power of the signal from the medium. Hence,

Pm. = Pas --

(4)

substitute) between the output terminals of the equipment (or the output metering terminals) and the powermeasuring equipment. All measurements outlined under "Broadband Noise Measurements" may be repeated for each of aseries of frequencies throughout the pass band of the system. The results, in terms of power, are then divided by the equivalent bandwidth for a continuous
spectrum of the filter system at each test frequency. Plots of these values as functions of frequency may then be made to indicate the spectral-noise density of the system (Section 3.2.1), the equipment (Section 3.2.2), and the medium (Section 3.2.3).
It is necessary that discrete single-frequency spectral lines (from power frequency sources, incompletely erased tone recordings, and the like) be treated separately. Readings of the power output of such interfering
signals may be utilized by subtracting from them the mean of the power readings of two similar unaffected adjacent noise spectral bands, spaced at an equal frequency interval on opposite sides of the spectral line. The resultant value should not be divided by the bandwidth of the filter, but should be plotted as aspectral line of the indicated amplitude.
Reasonably satisfactory measurements of this sort may be made by connecting a standard narrow-band wave analyzer across the output load resistor. In this case the error indication for continuous spectrum noise signals must be corrected by comparison with a simple power-indicating meter, which may be connected to the output via asingle narrow-band filter.

The ratio (P,,,,/P,,,,,) is the single-frequency-signal to noise power ratio of the medium, so that

(S/N).=

= (Pm --

P..). (5)

The latter ratio may be converted to the decibel scale in the n-ormal way.

3.3 Unweighted High-Frequency Noise Measurements
A 250 cps high-pass filter, with 18 db per octave attenuation below 250 cps, is connected between the output terminals of the equipment and the load and measuring device. All measurements outlined under "Broadband Noise Measurements" may be repeated to obtain the signal-to-noise ratio corresponding to the portion of the spectrum, which is essentially free of the low-frequency vacuum tube "flicker" noise of the playback preamplifier input stage and hum of the power-line frequency and its major harmonics.

3.4 Noise Spectrum Analysis
The noise spectrum may be analyzed by insertion of avery narrow band pass filter of variable frequency (a number of interchangeable filters with aseries of fixed central frequencies may be inserted, one at atime, as a

3.5 Weighted Noise Measurement
Appropriate contour curves may be used as a basis for establishing aweighted response. It should be noted that when the ultimate use of the reproduced signal is to actuate some mechanism such as the human ear adifferent weighting characteristic must be substituted. Weighted measurements are particularly valuable in conjunction with studies of the relative operational effects with different system noise conditions. They should therefore be applied in ameasurement procedure similar to that of the Section 3.2 "Broadband Noise Measurements."
3.6 Instantaneous Noise Voltage Measurements
The instantaneous voltage may be caused to deflect the electron beam of acathode-ray oscilloscope so that the position of the spot of light on the screen is proportional to the voltage. A continuously moving photographic film or tape may be passed through a camera at an appropriate speed to resolve the recorded transverse movement and so to plot the noise voltage as a function of time. Short record intervals of this sort may be utilized for determining the various characteristics of the noise output. This method may be applied for both system and equipment noise measurement.

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513

Reliability of Airborne Electronic Components*

B.G.BROMBERG t AND R.D.HILL,JR:t

Summary--A review of typical electronic component failures shows that failures occur because of insufficient reliability per component, combined with the multiplicity of components utilized in typical electronic assemblies. Further, it is shown that failures do not occur in a manner described by the classical Gaussian description but rather by an exponential description which indicates adecreasing number of failures per unit time with time. Means for increasing reliability of components are discussed, with emphasis on mechanical ruggedness and resistance to severe environments. Replacement of electronic tubes by transistors and magnetic amplifiers is also discussed.

tively long-average tube life, the number of hours of operation of the equipment between tube failures is remarkably low. Typical values are that average tube life in reasonably well-designed equipment can range from
1600 to 6500 hours, with the number of operational hours between failures ranging from 14 to 30 hours.
The over-all reliability of a piece of equipment is a
function of its complexity and reliability of its components. The complexity of an equipment is difficult to

I.STATUS OF RELIABILITY
I A. Statistics T IS WELL KNOWN throughout the aircraft and guided missile industry that electronic equipment needs vast improvement in reliability. Because of the generally poor reputation attributed to electronic equipment many key engineers in these and other industries have atendency to use most any means other than electronic to achieve a certain design function. Yet, it is inconceivable that certain functions now performed electronically can be handled in any other way.
Thus, the present state of electronic science is that, on
one hand, it holds the key to achieving what is now impossible in any other way and, on the other hand, it requires extensive effort to raise the level of reliability to
that of mechanical and hydraulic applications.
All electronic equipment contains a multiplicity of various components. In determining which components contribute most to the label of unreliability it is highly informative to examine the large amount of statistical data which is being accumulated by various government
agencies and firms engaged in the manufacture or use of electronic equipment. Table Iis acomposite summary of faults found in typical production runs of guidance receivers for a guided missile, of radar units for airplanes, and airborne automatic control equipment. It is immediately apparent from Table Iand other similar
data that the principal component, but by no means the
only culprit, which has caused repeated and unexpected failures is the electron tube. The seriousness of this situation is all the more emphasized when it is realized that the individual tubes were selected and completely tested prior to installation in the airborne equipment.
The statistics of electron tube failures observed in a variety of equipment show that, in spite of the rela-

TABLE I DISTRIBUTUON OF FAULTS IN PRODUCTION RUN OF TYPICAL
AIRBORNE ELECTRONIC SYSTEMS

Item 1. Electron tubes 2. Reistors 3. Condensers 4. Wiring errors 5. Dry rectifiers 6. Mechanical items 7. Burn-outs 8. Miscellaneous

Per Cent of Total
Faults 64.0
8.8 7.2 6. , 4.5 2.4 1.1 5.8 100.0

indicate in anything but comparative terms. In electronic equipment complexity may be designated by the . number of electron tubes which must operate simultaneously if the total equipment is to perform its desired function. Since the electron tube is the chief component contributing to failure, the theory of probability utilizing the reliability and number of electron tubes can indicate some useful trends. Before presenting this analysis, it should be pointed out that it is not rigorously true that an analysis based on electron tubes only is valid in all cases; for amore general solution, the relative reliabilities and numbers of other electronic components such as condensers, resistors, transformers, potentiometers should be evaluated.
Since the reliability of each component of an assembly can reasonably be considered to be independent from each other, the total reliability of the assembly can be stated exactly the same as the well-known probability of simultaneous occurrence, namely,

RTotal = RI'R2 R3 ···Rnt

(1)

*Decimal classification: R520XR004. Original manuscript received by the Institute, May 14, 1952; revised manuscript received September 1, 1952. Presented to the St. Louis Section of the IRE Januiry 24, 1952.
tMissile Engineering Division, McDonnell Aircraft Corp., St. Louis, Mo.

where RTotai =reliability of assembly, and RI,R2 · · ·R,, are the reliabilities of each component.
From this expression the curves of Fig. 1can be obtained by assuming that the reliability of each compo-

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PROCEEDINGS OF THE I.R.E.

April

nent is equal. The curves of Fig. 1bring out vividly that However, the history of tube failures in service does not the reliability of components comprising a moderately show anormal-type distribution.

complex assembly must be several orders greater than

LaGasse and Dean' have shown the number of air-

that expected of the assembly. Another conclusion that ·craft radio tubes rejected in each 100-hour interval of

can be seen easily from (1) is that asmall group of less life for agroup of 1,912 tubes. These records show that

reliable components operating in conjunction with a group of highly reliable components will strongly control the reliability of the composite.

(a) more failures occurred in the first interval of time than in any other,
(b) for each succeeding interval of time, a smaller

1.00

number of failures occurred,

(c) although certain tubes lived for over 3,000 hours

80

of operation, the mean time for failure was 583

COMPONENT RELIABILITY .60

hours.

OVERALL

RELIABILITY ·40

.99

A graph of LaGasse and Dean's records is shown in Fig. 3. The curve of failures appears to be ahyperbola

asymptotic to both axes or an exponential curve. This

.20

type of histogram for electron tubes has been substan-

(a)

o

.9

tiated by a large majority of the statistics which deal

io

50 100

200

300

400

with tubes in actual service conditions.

NUMBER OF COMPONENTS

140

1 00 120

.80
.60 OVERALL RELIABILITY 40
.20

100

NO. OF

FAILURES

PER

80

100 HOURS

40

40

7

20

(b) 97
COMPONENT RELIABILITY
Fig. 1--Reliability dependence on (a) number of components and (b) individual component reliability.
The records of failure of components in service indicate another interesting fact. The failures of corn ponents, and this is not restricted only to electron tubes, do not show afailure history that in any way resembles the typical probability curve shown in Fig. 2. The distribution of failures indicated in Fig. 2is called the normal or

FREQUENCY OF
FAILURES

11ME

GAUSSIAN DISTRIBUTION

Fig. 2--Classical probability distribution.

Gaussian distribution, and it can be observed in the laboratory by subjecting a number of individual components to a typical life test and plotting the number
of failures occurring during certain, consecutive intervals of time. This is the type of histogram which is obtained in the usual life test run on incandescent lamps.

°o 4

8 12

16

20 24

28

32

TIME IN HUNDREDS OF HOURS

EXPONENTIAL DISTIMUTION

Fig. 3--Observed failure distribution.

B. Means of Increasing Reliability
The actual problem of reliability lies basically in the mechanical design of the package with emphasis on the following categories: (1) general mechanical ruggedness, (2) design for shocks, (3) design for vibration, (4) moisture proofing, (5) heat dissipation, (6) pressure changes and (7) temperature changes.
Although these seven design aspects are all important in the reliability makeup of any electronic system, it has
been observed that shock and vibration are probably the most important failure-causing environment. This
can be seen by examining the reliability figures of ground, shipborne, and airborne equipment. The order of reliability falls definitely into three orders of magnitude, with stationary ground equipment being the most reliable of the three types and airborne equipment being the least reliable. It can be expected by extrapolation that electronic equipment in guided missiles, which gen-
erally subject their contents to vibration and shock several orders of magnitude greater than that of inhabited aircraft, needs special attention if reliability is to be achieved.

J. E. M. LaGasse and W. W. H. Dean, "Tubes at work," Ekctronics, vol. 14, p. 56; November, 1941.

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Bromberg and Hill: Reliability of Airborne Electronic Components

515

The purpose of this paper is to emphasize the need for
reliability and to indicate several ways of obtaining improvements in reliability. It is not practicable to make this an exhaustive account of such means, but rather a provocative listing of certain attacks which have been considered by the authors. Based on the statistics and probability studies indicated previously, the following methods of improving the reliability of electronic equipment appear logical:

equivalent tubes available before the ARINC tubes. In a run of about 1,500 tubes of the type 5654, which is the 6AK5 equivalent, it was observed that there was one failure in the first 1,000 hours and only 32 failures in a total of 3,950,000 hours of operation.
From this data it is obvious that ARINC tubes should be used whenever possible. In most cases the
ARINC tubes are directly interchangeable with their JAN equivalents, and in the case of three tubes the

(a) improvement in reliability of electron tubes, (b) use of redundant circuits, (c) elimination of all or some of the electron tubes by
more reliable components, (d) design for shock and vibration environments.
These four methods are discussed in the following sections.

substitution can be made by considering only the effect of aslight increase in cathode heater current.
On the surface it might appear desirable to extend the ARINC techniques to all tube types. Such an un-
dertaking would undoubtedly dilute the ARINC effort and might well lead to little or no improvement over
existing JAN types. An example of this was the recent effort by the government services to obtain ruggedized

C. Improvement in Reliability of Electron Tubes
Basically, an electron tube is a mechanical structure which, among other things, depends on maintenance of

versions of many of the JAN types. These will be recognized as the as the 6SN7Ws, 6AQ5Ws, 6X4Ws, and so forth.

its geometry for proper functioning. In addition, the re- D. Use of Redundant Circuits

liability of electron tubes requires reasonable uniformity of the thermionic property of the cathode throughout
the life of the tube. Failures in tubes can be attributed almost exclusively to failures in these two aspects.
The Aeronautical Radio Incorporated (ARINC) inaugurated in 1946 a program with certain tube manufacturers to improve the life of asmall number of commonly used tube types. The basic goal of the program was the improvement of existing tube structures and
manufacturing techniques to the point where a much

In addition to increasing the reliability of components
comprising an assembly, the theory of probability points to another means of obtaining ahigh degree of over-all
reliability. This is the use of aduplicate system in parallel with the original, wherein the functioning of either one of the parallel systems results in successful operation of the assembly. This fact can be expressed mathematically.

RTotai = 1-- (1 -- ¿D'- \n

(2)

higher degree of reliability than previously available could be expected. Cost considerations of such an improvement program were of secondary significance.
The ARINC tubes and the more recently offered reliable tubes manufactured by Raytheon are designed to withstand shock and vibration by minimizing the

where
RTotal = reliability of the over-all system, R,, =individual reliability of the component sys-
tem which is paralleled by similar systems, =number of systems being paralleled.

length of the internal elements and by having all parts
designed as fixed end columns and beams. Dimensions are held to much closer tolerances than had been used before; for example, critical grid dimensions are held to +0.0005 inch. Exhaustive inspection techniques sometimes involving binocular microscopes are utilized.
After manufacture each tube is given a burning-in period of 50 hours under normal operating conditions. The

An example to clarify this equation is: If asubsystem
has areliability of 80 per cent, and 3of these systems are paralleled, the over-all reliability has increased from 80 per cent to 99.2 per cent.
The use of redundant systems may also permit installation in aircraft of each system in adifferent orientation or in adifferent location (as compared to the other sys-
tems comprising the redundancy) so as to minimize the

burning-in period serves to stabilize the electrical characteristics and, more important, has been found to re-
duce the number of early-life failures. To improve the probability of increasing the reliabil-

effects of known or unknown environments as extreme temperatures, vibration, moisture, and so forth.
E. Elimination of Electron Tubes

ity of electron tubes, the ARINC program was pur-

As stated earlier, electron tubes have been found to be

posely limited to a small number of tube types-- namely, ten.
The statistics of the ARINC tubes in active service show areliability equivalent to airborne failures of not more than 2.5 per cent in the first 1,000 hours of opera-
tion. This rate of failure is to be compared to arate as high as 30 per cent in the first 1,000 hours for the best

the cause of about 64 per cent of the failures of electronic equipment; hence, elimination of this troublesome item
should allow alarge increase in reliability of the over-all electronic system. In general, there are about three satisfactory substitutes for electron tubes. These are the transistor, the magnetic amplifier and the selenium rectifier.

S16

PROCEEDINGS OF THE I.R.E.

April

Transistors are a recent development which utilizes semiconducting materials to provide control over the flow of electrons. Until the end of World War II these devices were germanium 'diodes, and were limited to such functions as rectification and pulse-shaping operations. Early postwar developments produced the emitter-collector type transistor which could perform some of the functions of the triode. These early transistors, however, were extremely noisy and could not be produced with consistent characteristics. More recent developments have led to the n-p-n and p-n-p type transistors, and it appears that these types are much improved from the noise standpoint and can be produced with consistent characteristics.
Table II, which was derived from work by Wallace and Pietenpol,' gives some pertinent characteristics of the latest n-p-n types.
TABLE II
N-P-N TRANSISTOR CHARACTERISTICS

Noise figure Power gain Efficiency Power consumption Frequency response

10-20 db at 1,000 cps 40-50 db per stage 48% for Class A 0.6 ov for an audio oscillator <5 kc with full gain

As can be seen from the table, the transistor's weak features are its noise figure and its frequency response. These features naturally limit the substitution of transistors for vacuum tubes.
The magnetic amplifier is certainly not anew device to the electronic field. Until the last three to five years, however, the magnetic amplifier was limited to poweramplifier and voltage-regulator applications. Develop-
'R. L. Wallace and W. J. Pietenpol, "Some circuit properties and
applications of npn transistors," Bell Sys. Tech. Jour., vol. XXX, p. 530; July, 1951.

ments in the field of regenerative magnetic amplifiers have made these devices more adaptable for replacing vacuum tubes.' It is now possible to obtain power gains of up to 50,000 with an input level of 10-4 watts. With gains of this order available, it is possible to control a relay with the signal from photo cells, thermo couples, and so forth, amplified only by amagnetic amplifier.'
The major advantages of the magnetic amplifier are its efficiency, high power gain, resistance to shock and vibration and, particularly, its reliability.
Application of the selenium rectifier to electronic systems as areplacement for power rectifiers and bias supplies is well known and will not be elaborated on here. It is interesting to note, however, that recent developments in hermetic sealing of selenium rectifiers have overcome many of their former disadvantages, such as susceptibility to humidity and salt-spray exposure. Improvements have also been made in the reliability of selenium rectifiers in relatively high ambient temperatures.
CONCLUSION
It is well recognized that the problems involved in the design and production of reliable airborne electronic equipment are tremendous, but with acontinued effort to improve vacuum tubes--such as the AR1NC and individual tube manufacturers' programs, by the replacement of tubes with transistors, magnetic amplifiers and selenium rectifiers where possible, by redundant design, and by agreater concentration of effort on the mechanical design of electronic equipment, the challenge can be met and we can produce reliable airborne electronic equipment.
$ "Magnetic Amplifier Design Handbook," Bulletin 2000, Vickers Electric Division, Vickers, Inc., St. Louis, Mo.; 1949.
4 "Application of magnetic amplifiers," Section of Proc. NEC, Chicago, III., 1951, vol. VII, pp. 235-262; February 15, 1951.

Fluctuation Noise in aMicrowave Superregenerative Amplifier*

THEODORE S. GEORGEt, SENIOR MEMBER, IRE, AND HARRY URROWITZI, ASSOCIATE, IRE

Summary--A brief review of superregenerative (sr) operation is followed by the substitution of Rice's Fourier series representation for noise current into the expression for the output of an SR amplifier. Expressions are derived for the noise figure. It is then shown how areflex klystron can be used as the active element. Expressions for the noise figure in terms of the klystron parameters are derived. Calculation for a hypothetical, but realistic, case shows that low noise figures are obtainable if certain conditions are met. In particular, it is shown that deliberate introduction of beam current, with its consequent shot noise, during the quiescent interval provides a smaller over-all noise figure.
Decimal classification: R138.6. Original manuscript received by the Institute, February 18, 1951.
tPatrick Air Force Base, Cocoa, Fla., formerly with Philco Corporation, Research Division, Philadelphia, Pa.
Research Division, Philco Corporation, Philadelphia, Pa.

THE SUPERREGENERATIVE PRINCIPLE
UPERREGENERATIVE AMPLIFIERS have been treated extensively in the literature." The superregenerative (sr) amplifier under consideration in this paper is one for microwave application. It may be considered to be atuned circuit containing an inductance, capacity, and a shunt conductance which
'W. E. Bradley, "Superregenerative detection theory," Electronics, vol. 21, September, 1948. Also Philco Corporation Research Report No. 32 "Theory of the Superregenerative Receiver," Philadelphia, Pa.; 1947.
2 L. Riebman, "Theory of the superregenerative amplifier," PROC. I.R.E., vol. 37, p. 29; January, 1949. This article contains abibliography.

1953

George and Urkowitz: Fluctuation Noise in a Microwave Superregenerative Amplifier

517

varies with time. Physically, the tuned circuit may be aresonant cavity. A simplified circuit of the sr amplifier is shown in Fig. 1.
A signal current, i(t), is fed into the tuned circuit, and avoltage, e(t), is obtained. A quench generator controls g(t), the varying conductance shunting the tuned circuit. This conductance is composed partly of the losses of resonant cavity or inductor-capacitor combination, and partly of anegative conductance contributed by an electron tube periodically energized by the quench
generator. In the case of a microwave amplifier, the negative conductance may be contributed by the bunched electron beam of a reflex klystron, and controlled by a quench voltage on the control grid (or, in the absence of a control grid, on the cathode) of the klystron to quench the beam.

CaNIMA·100

DETE.C7IDAL AND Flo-IM/S

De ,"ÉCTE 4NC, Se·007.E0
WT.P,T

eaavinaa, CONOUCT.NCIE,
Fig. 1--Simplified stsperregenerative amplifier.
The sr obtains its amplification by asequential series of operations. Oscillations are caused to build up in the resonant circuit when the negative conductance is introduced under the control of the quench waveform. The amplitude to which oscillations build up at any time is dependent upon the strength of oscillations in the circuit caused by an input signal even prior to the time of introducing the negative conductance. After the signal has built up several orders of magnitude, the negative conductance is removed by the quench generator turning off the klystron electron beam or introducing positive conductance, and oscillations are quenched. The quench cycle is then repeated to cause periodic buildup and decay.
The instantaneous output, e(t), of Fig. 1is thus not only a function of the instantaneous i(t) and g(t), but also of the past history of i(t) and g(t). Consequently, e(1) is a function of the waveform of g(t) as well as its instantaneous value. If the so-called "ideal" quench waveform' is used, the operation of the sr amplifier may be divided into three phases, as shown in Fig. 2. During the listening interval the sr amplifier is most sensitive to an input i(t), and the electron tube may be turned off or there may be asmall beam current to make the listening conductance small. The beam current is suddenly turned to ahigh value at the end of the listening interval, and oscillation, determined by the signal across the tuned circuit, begins to build up. Before overload takes place heavy damping is applied to remove the built-up signal and to prepare the tuned circuit for reception of anew signal. Thus, it is seen that the output of the sr amplifier is asequence of sampling pulses.
3 W. S. Percival, U. S. Patent No. 2,171,148; 1939.

The expression for the detection output of the sr amplifier which will be used is the one developed by Bradley." Other expressions have been used by other writers.' Bradley's expression is

1 f

E(t) = -- ico0C

F(t, r)e-i°0Tii(r)dr,

(1)

where

C=shunt capacity of the tuned circuit, coo=(LC) -- "2,the resonant angular frequency, i(1) =the input driving current, e(t) the derivative of i(t), and F(t, r) is the "time aperture function" defined by

FO,

r)

=-

I exp [-

1 fg(t)dt], 2C

for t> r

(2)

o

,for r< t.

In (2) g(t) is the time-varying conductance of the oscillator circuit. The ideal quench waveform of Fig. 2 is used, and it is assumed that quenching is so severe that no appreciable energy comes through the network during the quench interval. It is further assumed that amplification is great enough that the amount of energy getting through the network during the listening interval (-12, 0) is negligible compared to the built-up signal level at the end of the build-up interval. Thus, in the output it is necessary to consider only the output func-

Fig. 2--Ideal queach Wd% eform.

tion between t=0and t=t 1.These assumptions simplify the calculations but are not so radical as to depart seriously from practice. F(t, r) will now be computed. Defining P(t) by g(t)IC, one has (see Fig. 2),

F(1, r)

exp [P- 22T

-P2i-t 1 for - < r <

= exl.) [ -- r)]. for 0 < r< 1.

(3)

4 L. A. Zadeh, "Band-pass low-pass transformation in variable networks," PROC. I.R.E., vol. 38, p. 1339; November, 1950. The expression given by Zadeh is similar to that derived by Bradley. In
"Correlation functions and power spectra in variable networks," op. cit., p. 1342, Zadeh gives amethod for treating the effect of noise upon
variable networks. The approach in the present paper may be considered an alternative to Zadeh's.

518

PROCEEDINGS OF THE I.R.E.

April

NOISE INPUT For the input noise current, the representation of Rice' will be used.

i(i)

1 = --
2

S C,, exp

k it-- ej.,,].

(4)

The series in (8) can be approximated by an integral in
which co,, becomes co and Au--kit». Now suppose that F(co) is flat and equals Fo.Then (8) becomes

E2(t) = 2exp [P111]Fo (1 -- exp [--Pad). TP1P2C2

(9)

In this representation the 0,, are random phase angles, with a uniform probability density function in the interval (0, 2r). Also

C,,2 = = Irfn,f,, = nAf,

C_,, = C,,,

clo-n =

On,

-- E 1 N F(f,,)àf = f F(f)df i2(t).

(5)

2

It is of interest now to compute the output power spectrum of the noise since this noise may be passed through other circuitry. To find the output power spectrum, the autocorrelation function is first computed. Then the power spectrum is found by taking the Fourier
transform of the autocorrelation functions. This is Wiener's theorem.' Written as aFourier series with pe-
riod T, (6) has the form

E(t) = E a. exp

Irmti

(10)

m--so

T

Here, F(f) is the noise power spectrum, and i2(t) is the mean square noise current, or total average power for aload of 1ohm. Substituting (4) into (1) and using (3), and assuming that exp [P111/2]>>1 and that Pi>>P2
(these assumptions are the same as those made before), there is obtained

where

1 f

(P11 21-jint)

= --

exp

dt.

CT o

2

Now the autocorrelation function of E(t) is

R(r) ave. 1E(t)E*(1 + 7-) }

E(t) = C exp 2 E exp

271-jn1

= AoEla,,l 2exp[ --

(11)

1-- exp [-- Pit2

2

X

P2

2

jwoti -- j4411 -- coo)

where (6)

Ao = --2F0 (1 -- exp
P2

(12)

To find the mean square value of E(t), (this is commonly called the average power) E(t) is multiplied by E*(t), its conjugate, and then the product averaged.

for F(co) =Fo,aconstant. Taking the Fourier transform to get the power spectrum,

Two averages must be taken; one with respect to 0,,, the random phase angle, and the other with respect to t

Fi(co) = f:R(r) exp [--jcar]dr

over the period, T, of aquench cycle. ave. IE(t)E*(1); = 2i1rT · " f ti E(b)e(t)dtdOn, (7)

= Ao z

ani26 (0

2rn\
T )

(13)

where (SP --(27rn/ T)] is the Dirac delta function in the

or

frequency domain. Equation (13) indicates a discrete

E2(t) = -- exp [Piti] EC,,2

C2Pi

,,

spectrum, with components at harmonics of the quench
frequency. Now suppose that the highest modulating frequency

1+exp [--P2l2]--2 exp [--P 221] cos (co,,--coo)t2

to be amplified is fo.The quench rate must then be as least 2fa.This is astatement of the general theorem that

X

--P422+ (co,, --coo) 2

(8) a time function containing no frequencies higher than fa is completely specified by aset of discrete ordinates occurring at a frequency 2fa.1 Then the detector of the

Now, from (5),

sr amplifier will be followed by a low-pass filter which cuts off above f,,, but below 1/T, the quench frequency.

&a 1

C,,2 = 2F(f,,)àf

=

2F(co,,)-- 2r

=

ir

6 S. O. Rice, "Mathematical analysis of random noise," Bell. Sys. Tech. Jour., vol. 24, p. 125; January, 1945.

6 H. M. James, N. B. Nichols, and R. S. Phillips, "Theory of Servomechanisms," MIT Rad. Lab. Series No. 25, McGraw-Hill Book Co., Inc., New York, N. Y., p. 273, 1947.
7 B. M. Oliver, J. R. Pierce, and C. E. Shannon, "The philosophy of pcm," PRoc. I.R.E., vol. 36, p. 1324; November, 1948.

1953

George and Urkowitz: Fluctuation Noise in a Microwave Superregenerative Amplifier

519

Therefore, the only component of the noise spectrum in (29) which is passed by this filter is the dc component, which is the component for n=0. This is Apla o12.Under our assumption that exp [Pit1/2]>>1,

8F0 exp [Pitd(1 -- exp [--F212])

E02(ti) =

C27.21'1 2P2

(14)

The noise power spectrum Fois the total noise spectrum from any source. Of course thermal noise is always present, and there may be shot noise present, too, if the electron tube is used to introduce asmall negative conductance during the listening interval. It will be shown later that some advantage may be obtained from this procedure. Thus we write

Fo = F1 -I- F2,

(15)

where F1=thermal noise power spectrum and F2 =shot

noise power spectrum. One can write Foas asimple sum

since thermal noise and shot noise are independent.

At the end of the listening interval, conditions change

radically. A large negative conductance is introduced.

This usually means an increase in the shot noise during

the build-up interval. The noise contributed during the

build-up interval in this way can be calculated as be-

r- fore. It turns out to be E2(1 1)= exp [Fiti] TP1C2

F'(w)dco

, (16)

_ wo2

4

Thus the noise figure is the ratio of the actual available noise power to the available output noise power of an ideal (no noise sources) network with the same gain characteristics. The external noise is assumed to be entirely thermal noise, and the internal noise is assumed to be due entirely to shot noise.
GNin can be interpreted as the noise through the
amplifier, due to the external source. This is given by (14) with F1of (15) substituted for Fo.Then

NF = 1± F2 F1

Fo'Pi FIFI(1 -- exp [ P2,2]

(20)

This has aminimum value for P2=O. In this case

NFmn = 1+F2+ Fo' F1 FiPit2

(21)

Equation (21) assumes that the other quantities are unaffected when P2-4/

THE USE OF A RELEX KLYSTRON
It was stated earlier that areflex klystron 2- " could be used in amicrowave sr amplifier. The structure of a reflex klystron is shown in Fig. 3. The accelerating potential for the electron beam is usually applied to the cavity resonator. A small negative potential applied to the repeller reflects electrons back to the gap. If there exists a sinusoidal voltage across the gap, the electron beam will be velocity modulated. The result of this velocity modulation is to "bunch" the electron beam.

where no)) is the power spectrum of the shot noise introduced during the build-up interval. For F'(0)= F0', a constant, and after passing through the video filter,
this becomes

8F0'(exp L 2

2 -- 1)

E12(11) =

C2T2Pi3

8F0' exp [Fed

(17)

C2T2P13

·

RE SOMATIC,. CAVITY

FOCUSING ELECTROO&

ILLICTROM

-\\\

cerwooe1

_

If ·=·
.

-7.-·._.:..·.-......-'7"."'--e-7.7"

.::::

Z",..f.

rz.=:., peffliumpt

CCNTROL. rIRID
FIRSONaTOR CAP

The total noise power output is the sum of (14) and (17). Consider now the problem of the noise figure of a
superregenerative amplifier. Noise figure is commonly defined as

S

-- in

N

NF =

(18)

S

-- out

N

where S stands for the available signal power, and N stands for the available noise power. Now the available power gain of the amplifier is usually defined as G= Sout/Sin, so that (18) becomes

NF =

Out

GNin

(19)

Fig. 3--Structure of areflex klystron.
"This bunching causes the electrons that are returned toward the anode (cavity) by the repeller to return through the anode gap in bursts or pulses, one each cycle. When these pulses pass through the gap at such atime that the electrons in the pulses are slowed down as aresult of the alternating voltage existing across the gap at the instant of their return passage, energy will
8J.R. Pierce, "Reflex oscillators," PROC. I.R.E., vol. 33, p. 112;
February, 1945. E. L. Ginzton and A. E. Harrison, "Reflex klystron oscillators,"
PROC. I.R.E., vol. 34, p. 97; March, 1946. 1°D. R. Hamilton, J. K. Knipp and J. B. H. Kuper, "Klystrons
and Microwave-Triodes," MIT Rad. Lab. Series No. 7, McGrawHill Book Co., Inc., New York, N. Y.; 1948.
11 K. R. Spangenburg, "Vacuum Tubes,» McGraw-Hill Book Co., Inc., New York, N. Y., p. 571, 1948.

520

PROCEEDINGS OF THE I.R.E.

April

be delivered to the oscillations in the resonator and will thereby assist in maintaining these oscillations." 2 This condition results from atransit time from resonator gap to repeller and back of approximately n+3/4 cycles, where n is an integer or zero. This action is equivalent to introducing a negative conductance in the cavity. The exact value of negative conductance which is introduced is proportional to the beam current. If the beam current is large enough, all the losses may be overcome and oscillations will build up until overload takes place, or the beam current is reduced, or the value of repeller voltage is changed. This is just the action desired in a superregenerative amplifier. It is possible for the beam current to damp the cavity, too. There is always some loading effect due to the beam absorbing energy from the cavity on the first passage. When the repeller voltage is of such a value as to cause the returned electron bunches to introduce negative conductance, the losses are reduced or overcome, but if the repeller voltage is of such avalue as to introduce positive conductance, then the beam loading effect is enhanced and severe damping may result. A large Q during the listening interval may be obtained by allowing sufficient beam current to make P2-4). P2=0 means infinite Q.
It is possible to write equations for the noise figure in terms of klystron parameters. To do this we use the small-signal theory as described by Spangenburgu and Terman' 2 from which the formulas to be used are obtained. First the following symbols are defined:
coo=rf angular frequency, resonant angular frequency of cavity.
t,, =time an electron spends in the gap space, in seconds.
ta =time an electron spends in the drift space, the space between repeller and gap, in seconds.
0, =coot, =gap transit angle, in radians. Od=(Odd= drift space transit angle, in radians. M= (sin [00/2))/0,,/2 =beam coupling coefficient. I (with appropriate subscripts) =direct beam cur-
rent in amperes. Vo=beam potential (accelerating potential), in
volts. GB =beam loading conductance in mhos (always
positive). G.= electronic transconductance, in mhos (negative
for buildup). GLB =equivalent shunt conductance of load and
resonator cavity, in mhos. GT =total conductance in mhos. K =Boltzmann's constant =1.38 X10-23 joules per
degree K. To=Kelvin temperature, degrees.
e--electronic charge -= 1.6 X10-'s coulombs. C= shunt capacity, in farads.

The following three formulas may therefore be obtained.

Gr = Gut + GB--

(22)

O.

GB =

M COS

(23)

2I V0I

2

Here

Gel= V2o d VL iX(X) 1_I1 Sin di ·
MITIOa 2V0

(24) (25)

where MX) is the Bessel function of first kind and first order, and V1 is the amplitude of the signal voltage. We shall assume that Ji(X)/X is adjusted to have its maximum value of one half, although actually this is
impossible in practice because the signal strength changes during build-up. Defining the quantity B by

M2 - B==

Op M 2

M cos -- -- 0dIsin Ocl I

2 2

Vo

, (26)

substituting (23) and (24) into (22), and using (26),

there is obtained

G = GLB -- IB.

(27)

Let

beam current during the listening interval,

I2=beam current during build-up,

GT1 =total conductance during listening,

and GT2= total conductance during build-up.

Then recalling that P(t)=g(t)/C,

Gz.n -- BII P2 =

(28)

Pl = BI, GLB

(29)

The thermal noise spectrum is given byn

F2 = KTo.

(30)

The power spectrum of shot noise is 2e/," for a temperature-limited cathode. For space-charge limited current, the shot noise is less. However, at high frequencies, the smoothing effect of space charge is reduced. Therefore, it will be somewhat pessimistically assumed that the shot effect has the spectrum 21.for the reflex klystron. All of this shot noise current is not effect across the resonator gap, because the coupling between beam and cavity is not perfect. The power that is coupled from the beam to the cavity is proportional to /D. Therefore, the shot noise spectra during listening and during buildup, respectively, are

F2 = 29I1M2,

(31)

Fo' = 2I2M 2.

(32)

"F. E. Terman, "Radio Engineering," McGraw-Hill Book Co. Inc., New York, N. Y., 3rd ed., p. 444, 1943.

13 S. Goldman, "Frequency Analysis, Modulation, and Noise,» McGraw-Hill Book Co., Inc., New York, N. Y., p. 390; 1948.
14 Ibid., p . 362.

1953

George and Urkowitz: Fluctuation Noise in a Microwave Superregenerative Amplifier

521

We shall write the noise figures for two cases. 1. The beam current during listening is zero. This
means that P2 0 and that, in (20), exp --PAWL
Also F2=0. 2. Enough beam current is allowed during the listen-
ing interval so that the losses in the cavity are just cancelled, making P2=0. This means we must use (21) for
this case. We have then, the following, using (20), (21), (28),
(30) and (32), Case 1:

2eGLuM 212 NF I = 1+
KTo(BI2 -- Gut)

(33)

Case 2:

NF2 = 1

2EM 211 KTo

2ECM 2/2 KT0t2(B/2 -- GLE)

(34)

It should be noted that /2 is always large enough so that oscillations build up during the build-up interval. It is seen that this means

GLR 12 >

(35)

Equations (33) and (34) have no meaning for /2<(G LR/B). A minimum noise figure is approached
asymptotically. For Case 1, this minimum is

NF L,' = 1± 261.1331 2 KT0B

(36)

and for ('ase 2, 2E11312 2ECM2
NF2m = 1+ KTo + KT012B

(37)

A qt e3tion of particular interest is whether it is ever advantageous to introduce beam current, and therefore shot noise, during the listening interval to make P2=0. The answer is yes, if it is desired to get a lower noise figure. We have considered ahypothetical, but realistic, case in which numbers were substituted into (33) and (34). In fact, the numbers chosen are actually approximated in aQK205 reflex klystron. The conditions were as follows:

resonator gap spacing =0.020 inch

resonant frequency

=10,000 mc

cold Q of cavity and load =500

shunt capacity

=1 µµf

beam potential

=1,000 volts

listening time

=0.2 µsec.

The mode of operation considered was Od=(23/4)(2r) radians (51 cycle mode). From the conditions above, all the necessary parameters may be calculated to find the noise figure. Results for the 5-2- cycle mode are shown in Fig. 4. In this figure, the independent variable is incremental beam current, which is that in excess of the current necessary to produce oscillation. Thus
GLR /2 --
Fig. 4clearly shows the advantage obtained by allowing enough beam current during the listening interval to cancel the cavity losses. The following conclusions may be drawn for obtaining low noise figure.

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e3:02/4104.33à. 113·04 0.0.1330e 13.33.31.31.31.0·1.10.1041..6.3·0011131

000

Fig. 4--Incremental beam current during build-up, in ma. Noise figure of ahypothetical superregenerative amplifier.

1. The listening interval should be as long as possible. 2. The cold listening Q should be as high as possible. 3. The direct beam current during build-up should
be as high as possible consistent with operation in the linear mode (no overload). If the build-up interval is kept short, high beam current may be used. 4. It is profitable to allow sufficient beam current during the listening interval to make P2=0. 5. A high mode of operation will allow low noise figures to be obtained with smaller beam current.
ACKNOWLEDGMENT
The authors wish to acknowledge the generous assistance of A. C. Munster and L. T. Carapellotti of the Research Division, Philco Corporation.

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The Use of Admittance Diagrams in Oscillator Analysis*

HERBERT J. REICH ,FELLOW, IRE

Summary--Much useful general information concerning the behavior of oscillators may be obtained by means of a graphical analysis based upon curves of electronic and circuit admittance. A curve of electronic susceptance versus electronic conductance and acurve of circuit susceptance versus circuit conductance are plotted in the same diagram. At points of intersection of the two curves the electronic and circuit admittances are equal in magnitude and phase. These points therefore indicate possible equilibrium values of frequency and amplitude. This method of analysis explains observed oscillator phenomena, such as amplitude and frequency hysteresis, dominance of one mode of oscillation over other modes, pulsing, and electronic tuning. The function of this paper is to present asummary of information previously found only scattered throughout the literature on oscillators.
INTRODUCTION
1 r --1HE ANALYSIS to be presented in this paper is helpful in explaining many aspects of oscillator behavior. It is not ordinarily directly applicable to the quantitative prediction of the operating characteristics of oscillators of known parameters, although it may occasionally serve as a guide in oscillator design. Most of the ideas contained in the paper are not new, but may be found scattered throughout the technical literature on oscillators.
Two-terminal and Four-terminal Oscillators
Electronic oscillators may be classified as twoterminal and four-terminal types. A two-terminal electronic oscillator is one that consists of a two-terminal oscillatory circuit shunted by some form of two-terminal electronic device capable of transferring power to the oscillatory circuit from the source of direct voltage. The electronic element must exhibit an admittance between its terminals that has anegative conductive component, i.e., the application of an alternating voltage to the terminals must result in the flow current in opposition to the applied voltage. Oscillation can occur if the magnitude of the electronic conductance is equal to or exceeds the conductance of the oscillatory circuit shunted across the element. In microwave devices the electronic admittance results from the presence of moving electrons within a gap across which the voltage is impressed. At lower frequencies, as in dynatron and transitron oscillators, secondary emission or other phenomena may be involved. The reflex klystron is an
*Decimal classification: R133. Original manuscript received by the Institute June 3, 1952; revised manuscript received January 5, 1953. Presented at the New England Radio Engineering Meeting, Boston, Mass., May 10, 1952.
tDept. of Electrical Engineering, Yale University, New Haven, Conn.

excellent example of a two-terminal microwave oscillator.
In four-terminal oscillators, the electronic device is a four-terminal element. Application of alternating voltage between one pair of terminals results in the flow of alternating current through a circuit connected across the other pair. In other words, the device has a transadmittance. Oscillation is obtained with such adevice only when the output terminals are connected to the input terminals through a suitable feedback network. Triode, tetrode, and pentode feedback oscillators and two-resonator klystrons are examples of four-terminal oscillators.
Electronic admittance and transadmittance are ordinarily essentially independent of frequency over the frequency range covered by a tunable oscillator. They are, however, dependent upon amplitude. Although their magnitudes may increase with voltage amplitude at low amplitude, avalue of amplitude is always reached beyond which the magnitude of electronic admittance or transadmittance falls with increase of amplitude. This characteristic is essential to limitation of amplitude of oscillation, and results from nonlinearity of the electronic device.
Two-terminal Oscillatory Circuit
The oscillatory circuit connected across the electronic element of a two-terminal oscillator ordinarily consists of some type of resonator to which an external load is coupled. At frequencies up to several hundred megacycles per second, the resonator usually takes the form of a lumped-element circuit. In the microwave range, however, the characteristics of lumped-element circuits are unsatisfactory and other types of resonators, such as cavity resonators or sections of transmission lines must be employed. Although microwave resonators do not in general behave like simple parallel resonant circuits, in the vicinity of a resonance frequency they may ordinarily be represented by an equivalent parallel combination of constant-lumped inductance, capacitance, and conductance, the values of which are different for different modes of resonance.
In many oscillator circuits the external load is connected to the output resonator through a transmission line. At the lower frequencies the line is usually short in comparison with the wavelength and the effect of the line is negligible. In microwave tubes, on the other hand, alength of line large in terms of the wavelength is usually an integral part of the tube structure, and

1953

Reich: The Use of Admittance Diagrams in Oscillator Analysis

523

cannot be eliminated. The coupling line must, therefore, in general be taken into consideration in an equivalent circuit of the oscillator. The general form of the equivalent circuit of atwo-terminal oscillator is shown in Fig. 1, in which Y. represents the electronic admittance between the electrodes across which the resonator is shunted, and G,., C,., and L,. represent the equivalent resonator conductance, capacitance, and inductance

by the symbols Y., G,, and Bc.The circuit admittance is the sum of the resonator and load admittances, as stated by the relations:
Yc = Y,. + 171
(4)
B. = B,. + B1 --- co(C. + C1)-- (1/wL, -F 1/coLi).

An exact analysis of the equivalent circuit of Fig. 3

is complicated by the dependence of G. upon voltage

amplitude. For this reason the assumption will first be

made that G. is constant, and the effect of variation of

G. upon the behavior of the oscillator will be made sub-

sequently. The dependence of B. upon amplitude causes

Fig. 1--Equivalent circuit of atwo-terminal oscillator.

some change of frequency as the amplitude of oscillation builds up, but the change is normally so small that

in the vicinity of a resonance frequency. M represents the mutual inductance between the coupling coil or loop

B. may also first be assumed to be constant in making the analysis.

and the resonator, and L' represents the self-inductance

of the coupling coil or loop. Y is the admittance of the

load in which the transmission line is terminated, and

Yo is the characteristic admittance of the line. In low-

frequency circuits, Y may be considered to be con-

nected directly across the coupling coil.

The transmission line, loaded at the far end by the admittance Y, may be replaced by the equivalent ad-

Fig. 3--Simplified equivalent circuit of atwo-terminal oscillator.

mittance Y1'measured between its input terminals. By well-known methods, the combination of the coupling loop and Y1'may be replaced by an equivalent admittance Yi shunted across the resonator admittance. The equivalent circuit may then be drawn in the form of
Fig. 2, in which Yr=G,.-1-jcuCr--

Variation of Y. with amplitude is an indication that the relation between the electronic gap current and the
voltage which produces it is not linear. Since one consequence of nonlinearity of circuit elements is the generation of harmonics in the current and voltage, it follows that variation of Y. with amplitude is always associated

with the presence of harmonics. A strictly rigorous

analysis would have to take harmonics into account or

Ve

Yr

else show that the presence of harmonics has negligible effect upon the steady-state frequency and amplitude,

even at large values of amplitude. Because the com-

plexity of a complete analysis tends to complicate an

Fig. 2--Simplified equivalent circuit of atwo-terminal oscillator.

interpretation of the results, and because the following treatment is intended to be of value principally in ex-

Although the electronic susceptance B. is essentially independent of frequency throughout the tuning range of most oscillators, at any oscillation frequency it may be considered to result from an equivalent inductance L. or capacitance C.. Fig. 2may, therefore, be drawn in the equivalent form of Fig. 3, in which G, C, and L have values given by the relations

plaining qualitatively some of the observed characteristics of oscillator behavior, harmonics will be neglected. The simplified analysis is valid at small amplitudes of oscillation; its application at large amplitudes is justified by the fact that the phenomena which it predicts are observed experimentally.
Under the assumption that all parameters in the circuit of Fig. 3are constant and linear, summation of the

G = G.+ C = C.+

+ GI CI

(1) currents at one of the nodal points yields the following

(2)

differential equation for the voltage V across the elements:

L = 1/(1/L. -I- 1/L,.± 1/L 1)

(3)

Electronic inductance L. and capacitance C. are not present simultaneously in the equivalent circuit.

d2V G dV

V

dt 2+

dt + LC = °

(5)

In the analysis that follows, the total circuit admit- in which G, C, and Lare given by (1) to (3). The solution

tance, conductance, and susceptance will be represented of (5) is

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PROCEEDINGS OF THE I.R.E.

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V = VoEat sin (cel + le)

(6)

in which

a = -- G/2C = -- (G o Gr G1)/ 2C

= --

G,)/2C

(7)

1 G2 A l 1

=

--

=

--

(8)

and the constants Voand 4, are the amplitude and phase angle of the voltage at the instant when t=O.
Equation (8) shows that the voltage can be sinusoidal only if IGI <2-V-CFL. Examination of (6) and (7) dis-
closes that, since the resonator and load conductances Gr and G1 are positive, sustained sinusoidal oscillation is possible only if the electronic conductance Gois negative and equal to or greater in magnitude than G,. If G. is negative and equal in magnitude to Gc,a is zero and the oscillation is of constant amplitude. If G. is negative and greater in magnitude than Gc,the amplitude of oscillation theoretically increases continuously. Actually, however, the dynamic value of Govaries with the amplitude of oscillation and, although it may remain constant or increase in magnitude over some ranges of amplitude, there is always some amplitude above which it decreases. Eventually, therefore, an equilibrium amplitude is reached at which the dynamic value of Go
is equal to G,. This amplitude is evidently dependent
upon the manner in which Go varies with amplitude, upon the resonator losses, and upon the load. · Equation (6) indicates that oscillation cannot take place unless it is started in some manner. In any actual circuit, the random thermal motion of electrons sets up random current pulses of sufficient magnitude to initiate the oscillation if the static value of Go,i.e., the value of Go at zero amplitude, is negative and greater in magnitude than Gc.
Physically, anegative value of Gois an indication that the motion of electrons through the electric and magnetic fields within the tube results in a conversion of
energy from the source of direct voltage to the source of alternating voltage across the electrodes. In an oscillator, the source of alternating voltage is the resonator.

Equations (9) and (11) represent the criteria for steadystate oscillation.
Since Go and Bo may ordinarily be considered to be functions of amplitude alone, and G, and Bc of fre-
quency alone, the solution of the simultaneous equations (9) and (10), expressed in terms of amplitude and frequency, should indicate the equilibrium values of amplitude and frequency. The functional expressions
for Y. and Y, are usually so complex, however, that an analytical treatment is difficult, if not impossible, and for some oscillators the functional relation between Y. and amplitude is not known. Much useful general information concerning the behavior of oscillators may be obtained from a graphical analysis, nevertheless, even when the exact forms of the expressions for Y. and Y, are not known. The graphical method consists in plotting the conductive and susceptive components of Y. and -- Y, at various frequencies in rectangular coordinates of admittance and susceptance, i.e., in plotting Boversus Goand --B,, versus --Goin the same diagram. Since the curves intersect at points where (9) and (11) are satisfied, the points of intersection indicate possible equilibrium values of amplitude and frequency.
The presence of the term a2 in (8) indicates that during the build-up and decay of oscillation the frequency of oscillation is less than the value at which Bo and B, are equal in magnitude. Since a2 is usually small in comparison with 1/LC, however, the following treatment will be simplified by the assumption that Bo and B. are equal in magnitude not only under steady-state oscillation, but also during transient periods. Under this assumption, the ordinate of the admittance point on the -- Y, curve in the admittance diagram must be equal to the ordinate of the admittance point on the Y. curve at all times.

Freq. increases 7
v 3

Freq. of b & req.y_afto

;Yc

B

Amph,.

icreq\ Zero amplit.

Admittance Diagrams for Two-terminal Oscillators Equations (6) and (7) show that under equilibrium
conditions a must be zero and
(9)

Time

(b)

(c)

Fig. 4--(a) Admittance diagram for a two-terminal oscillator. (b) Variation of frequency and amplitude during buildup of oscillation. (c) Admittance diagram; oscillation not self-starting.

When ais zero, (8) reduces to the relation

coC -- 1/wL, = 0.

(10)

Since ¡QC and 1/wL represent the capacitive and inductive components of the total susceptance B,,+B,,+B 1of the circuit of Figs. 2and 3, (10) is satisfied only if

B. -- (Br + B1) -- Bo.

(11)

Fig. 4(a) shows an admittance diagram in which the
curves of circuit admittance and electronic admittance are of arbitrary form. Equilibrium oscillation obtains for values of frequency and amplitude corresponding to point 3, since (9) and (11) are satisfied at this point. The zero-amplitude electronic-admittance point is
at 0. Under the assumption that Bo+Bc=0 during

1953

Reich: The Use of Admittance Diagrams in Oscillator Analysis

525

the build-up of oscillation, the circuit admittance and curve of input susceptance versus input conductance

frequency at zero amplitude correspond to point a of a section of transmission line of characteristic ad-

on the curve of -- Y. Because the magnitude of the mittance Yo,terminated in a load that results in a

electronic conductance at point 0 exceeds that of voltage standing-wave ratio S is acircle with its center

the circuit conductance at point a, a is positive in on the conductance axis and passing through points on

(6) and any initial disturbance, such as circuit or the conductance axis at which the conductance is equal

tube noise, initiates an oscillation of increasing ampli- to YoS and Yo/S. Increase of frequency causes the ad-

tude. As the amplitude increases, the electronic- mittance point to be displaced along the circle in a

admittance point moves toward point 1and the circuit- clockwise direction. (Equal intervals along the circle

admittance point moves toward point b. Inasmuch as do not correspond to equal frequency increments, the

the frequency increases along the circuit-admittance rate of change of position with respect to frequency

curve from ato b, increase of amplitude from 0to 1is being least at the point of minimum conductance and

accompanied by increase of frequency of oscillation. greatest at the point of maximum conductance.)

With increase of amplitude beyond that corresponding

to point 1, the electronic-admittance point moves back

toward the conductance axis, the displacement being

accompanied by an equal displacement of the circuit-

Freq. ·

admittance point and consequently by a decrease of

frequency. The amplitude continues to increase and

the frequency to decrease until the amplitude reaches

the value corresponding to the intersection at 3. This

point is stable, inasmuch as further increase of ampli-

tude would cause the magnitude of G. to become less

than G. and the amplitude therefore to decrease.

The rate at which the amplitude increases during the

(0)

build-up of oscillation to the stable value corresponding

to point 3is at every instant proportional to the difference in magnitudes of the electronic and circuit con-

Amp/if., o-mode

ductances. In the foregoing example, the greatest dif-

Freq., a'-mode

ference between the magnitudes of G. and G. occurs for an amplitude corresponding to apoint on the Y.-curve

Freq., a-mode

not far from that at which G. has its greatest magnitude.

Fig. 4(b) shows the general manner in which the amplitude and frequency vary with time during the growth

Time
(b)

of oscillation. The frequency fo is that at which the circuit susceptance is zero, and is therefore the resonance frequency of the resonator alone.

Fig. 5--(a) Admittance diagram of atwo-terminal oscillator capable of oscillating in more than one mode. (b) Variation of frequency and amplitude in two modes of oscillation during buildup of oscillation.

If the electronic conductance at zero amplitude is

smaller in magnitude than the circuit conductance, as in Fig. 4(c), ais negative at zeroamplitude and oscillation cannot start spontaneously. Should the circuit be driven, however, to an amplitude equal to or greater
than that at point 2, the amplitude will increase to the equilibrium value at point 3.
Under certain conditions, oscillation may start simultaneously at more than one frequency.' The manner in which the oscillation builds up is then complicated by
the fact, shown both theoretically and experimentally, that when voltages of two different frequencies are impressed simultaneously across agap, the electronic ad-
mittance for either voltage is changed by the presence of the other voltage. An example of an admittance diagram that predicts simultaneous starting at two frequencies is shown in Fig. 5(a), in which the circuit admittance is that of a section of transmission line. The

In Fig. 5(a), the zero-amplitude electronic conductance is greater in magnitude than the circuit conductance of both point aand point a'. Oscillation therefore starts at the frequencies corresponding to both of these points. Because of the lower magnitude of G. at point a than at point a', however, the oscillation corresponding to point a builds up much more rapidly than that corresponding to point a' and eventually reaches equi-
librium at point 3. The electronic conductance for the a'-frequency is reduced not only as the result of increase
of amplitude of the a'-oscillation, but also as the result of the rapidly increasing amplitude of the a-oscillation. At some time before the amplitude of the a-oscillation reaches that corresponding to point 3, G,, for the a'-
oscillation falls below the corresponding magnitude of G., and the a'-oscillation therefore dies out. Fig. 5(b)

W. H. Huggins, PROC. I.R.E., vol. 35, p. 1518; December 1947;
vol. 36, p. 624; May 1948.

shows general manner in which amplitude and frequency of the two modes of oscillation vary with time.

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PROCEEDINGS OF THE I.R.E.

April

Under certain conditions oscillations may exist simultaneously in two frequencies under equilibrium conditions.2Oscillation may also take place alternately in two modes, one dying down as the other builds up.
The particular curves discussed in the foregoing exam-
ples were chosen only because they are convenient in explaining important points in the analysis. The graph-
ical analysis based upon an admittance diagram may be
applied to any type of oscillator, regardless of the type of energy-converting device, type of resonator, or type of loading. The shape and position of the electronic-
admittance curve depends upon the type of electronic device and the operating voltages and currents; the shape and position of the circuit-admittance curve de-
pends upon the characteristics of the resonator and the extent and manner in which it is loaded.

into terminal l' to the resulting voltage of terminal 3' relative to terminal 4'. On the basis of these definitions,
the voltage V' produced between terminals 3'-4' by the application of avoltage V to the terminals 1-2 is given by the relation V' = -- Y,,, V/ Yg.
If V' is equal to V in phase and magnitude, i.e., if -- Yg,the voltages and currents in the network will
not be affected if the impressed voltage V is replaced
by the output voltage V' by closing the switch. In other words, the closed circuit will oscillate with constant
amplitude. Since V' must be identical with V in the closed system, oscillation can occur only at afrequency
that makes Y,,, and -- Yg equal in phase. If the magnitude of Y. is less than that of Yg,V' is less than V in the open system, and the amplitude of oscillation

Tube

Circuit

Fig. 6--Block diagram of afour-terminal oscillator.

Amp/it increase

\Fir-necqrueeansce y
-

V
2

3 Ym 4

3
Yt 4

Fig. 8--Admittance diagram of afour-terminal oscillator.

Fig. 7--Equivalent circuit of afour-terminal oscillator.
Admittance Diagrams for Four-terminal Oscillators
In four-terminal oscillators, the output of an electron tube is coupled back to the input through a four-terminal circuit, as in Fig. 6. If the tube is represented by a transmittance Y,,, and the circuit by a transfer admittance Yg,the circuit becomes that of Fig. 7. The electronic element is assumed to be unilateral; that is, application of an alternating voltage to terminals 1-2 results in the flow of alternating current through terminals 3-4, but the application of voltage to, or the flow of current through, terminals 3-4 has no effect upon the voltage or current of terminals 1-2. The electronic transadmittance Ym is defined as the ratio of the current into terminal 3to the voltage applied to terminal 1relative to terminal 2. The circuit transfer admittance Yg is defined as the ratio of the impressed current flowing
2 Schaffner, Hans, "Some Notes on Simultaneous Oscillations in Systems with Two Degrees of Freedom," E.E. Res. Lab., Eng. Exp. Sta., U. of Ill.

must die down when the system is closed. If the magnitude of Y. is greater than that of Yg, on the other hand, the amplitude of oscillation in the closed system increases.
The foregoing discussion indicates that four-terminal oscillators can be analyzed with the aid of transfer-
admittance diagrams. As in admittance diagrams for two-terminal oscillators, curves of B. versus G. and
- eversus --G gare constructed in the same diagram. Fig. 8 shows a diagram in which the curve of Y. is of arbitrary form and that of Y. is typical of coupled two-resonator oscillator circuits. Point 0on the Vm curve corresponds to zero amplitude. Oscillation starts at the frequency corresponding to point a, at which the phase angle of -- Ygis equal to that of Y.. Because the mag-
nitude of Y,,, at zero amplitude is greater than that of -- Yg,the amplitude increases and the electronic-admittance point moves toward point 1. Displacement of
the electronic-admittance point with increase of amplitude is accompanied by displacement of the circuitadmittance point, the two points always lying on the same radius vector. The increase of amplitude of oscillation is consequently accompanied by change of frequency. The amplitude continues to increase, with an
accompanying change of frequency, until point 1 is reached. This point corresponds to steady-state oscilla-

1953

Reich: The Use of Admittance Diagrams in Oscillator Analysis

527

tion, since further increase of amplitude would cause corresponding to point a. Change of tuning of the reso-

the magnitude of Y., to become less than that of -- Yg nator causes a displacement of the -- Y. curve, indi-

and the amplitude to decrease.

cated in Fig. 10 by an upward displacement of the Y.

curve. The intersection moves toward b, with continu-

Long-line Effect

ously decreasing frequency and amplitude. Further

As an example of the application of admittance dia- change in tuning causes the intersection to jump abgrams to the analysis of oscillators, admittance diagrams ruptly from bto c, with acorresponding abrupt decrease

will be used to explain a frequency- and amplitude-

hysteresis effect that is observed when load is coupled

to an oscillator resonator through a line that is long in comparison with the wavelength, as in the circuit of

Freq increase

Fig. 1. In the vicinity of one of the frequencies of reso-

nance, the shunt conductance of a resonator is essen-

tially constant, and the susceptance proportional to the

frequency. The admittance curve is astraight line paral-

lel to the susceptance axis. The input admittance of a

line terminated in an unmatched load is acircle, as in

Fig. 5(a). The transformer formed by the resonator in-

ductance and the coupling loop changes the magnitude

AMP

Cr.,a5e

G
Fig. 10--Admittance diagram used in the analysis of the long-line effect.

in frequency and increase of amplitude.' From cto dthe
frequency and amplitude decrease continuously and at dthe frequency again decreases abruptly and the amplitude increases abruptly to values corresponding to point e. Change in parameters in the opposite direction, so as to move the Y. curve downward relative to the -- Y. curve, results in similar abrupt changes in frequency and amplitude at fand h.

Fig. 9--Admittance diagram of atwo-terminal oscillator loaded by a long transmission line terminated in an unmatched load.
of the equivalent admittance shunting the resonator, and the self-inductance of the loop adds some series susceptance. The general form of the circuit-admittance curve, which is the resultant of the curve of the resonator admittance and that of the equivalent load admittance, is of the general form shown in Fig. 9. The size of the loops depends upon the degree of mismatch of the load and the line, the length of the line, and the tightness of coupling to the resonator.
Change of tuning of the resonator causes a vertical displacement of the loops in the circuit-admittance curve of Fig. 9. Because tuning of the resonator has anegligible effect upon the electronic-admittance curve, the loops move relative to the electronic-admittance curve. For ease of explanation, however, the loops may be assumed to remain stationary and the Y. curve to move relative to the -- Y. curve, as in Fig. 10. Suppose that the oscillator parameters have been adjusted so that the frequency and amplitude of oscillation are those

o-

Control parameter

c1.1

¡c ge

Control parameter Fig. 11--Amplitude and frequency hysteresis produced by the
long-line effect.

The general manner in which the frequency and amplitude might be expected to vary with resonator tuning

G.

oIfAtbhoevpeortthieonpooifntthaetcwuhrivcehonthwehiY.chcucrlviees

crosses itself, values of are smaller than those

of the portion on which blies. Oscillation may therefore build up in

the new mode and suppress that in the original mode even before the

intersection reaches point b. Where the jump takes place depends

upon the relative values of G. in the two modes.

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PROCEEDINGS OF THE I.R.E.

April

is illustrated in Fig. 11. Examination of Figs. 10 and 11

CONCLUSION

discloses that frequencies lying between points band h and between dand fare not observed as the tuning is changed back and forth. Other ranges of frequency are observed only when the tuning is changed in one direc-
tion or the other. These abrupt changes of frequency and amplitude, observed when a load is coupled to an

The principal value of the method of analysis presented in this paper lies in its ability to explain observed oscillator phenomena and characteristics. Although it is applicable to oscillators operating in all frequency ranges, it is particularly useful in the analysis of some types of microwave oscillators, such as klystrons. Be-

oscillator through a long line, are called the long-line cause of limitations imposed by assumptions made in the

effect. A similar analysis may be made for four-terminal mathematical treatment upon which the method is

oscillators.

based, and because of the difficulty in predicting the

A detailed analysis shows that the loops in the circuit- exact form of the electronic-admittance curves of some

admittance curves may be eliminated and that the long- oscillators, it is not in general very useful in the quan-

line effect should consequently be avoided by (1) match- titative predetermination of oscillator characteristics.

ing the load to the line, (2) making the line short in comparison with the wavelength, or (3) reducing the coupling of the line to the resonator. These predictions are in agreement with observed behavior.

4J. R. Pierce, "Reflex Oscillators," PROC. I.R.E., vol. 33, p. 112;
1945; Radiation Laboratory Series, Vol. 7, Sec. 11-5, D. Van Nostrand Co., Inc., New York, N. Y.; 1948; H. J. Reich, P. F. Ordung, H. L. Krauss, and J. G. Skalnik, "Microwave Theory and Techniques," Chaps. 12 and 13, D. Van Nostrand Co., Inc.; New York. N. Y.; 1953.

Transfer Characteristics and Mu Factor of Picture Tubes*

KURT SCHLESINGERt, SENIOR MEMBER, I.R.E.

Summary--An attempt is made to explain, analytically, the observed shape of the characteristic of kinescopes, which seems to follow asimple power law with an exponent between 2and 2.5. The difference from Langmuir-Childs law is due to the fact that the active-cathode area varies with grid voltage according to another po ver law.
The theory is applied to the modulator section of aconventional TV picture tube and also to various structural modifications thereof. As to the emission characteristic, gamma is consistently found to lie between 2.4 and 2.5 and seems to be little affected by structural alterations. The mu factor, on the other hand, is strongly influenced by any one of the changes in the four system parameters.
An experimental tube was built to check some of the predictions of the above theory. For the cathode current, agamma value of 2.43 was observed. The useful screen current followed apower law with an exponent of 1.9. The mu factor of this tube was found to fall within two per cent of the value computed from (15) of this paper.
INTRODUCTION
IT IS WELL KNOWN that the conventional type of television picture tube has anonlinear brightnesstransfer characteristic, which can be expressed by a simple power law with an exponent of approximately 2.5. An accurate way to measure this figure, also called the brightness-transfer constant or gamma-exponent has been given by Baldwin.' The influence of this nonlinearity on halftone rendition and the need for an inverse-power correction, or "rooter" operation, in the transmitter has been outlined in afundamental paper
*Decimal classification: R583.6. Original manuscript received by the Institute, January 22, 1952; revised manuscript received September 15, 1952.
Motorola, Inc., Television Research Department, Chicago, Ill. M. W. Baldwin, "Measurement method for picture tubes," Electronics, vol. 22, pp. 104-105; November, 1949.

by Oliver.2 It was further recognized at an early date
that the receiver nonlinearity has important bearing on
the visibility of noise in the picture. For agiven transmitter power the apparent signal-to-noise ratio can be much improved by the use of root-and-power response in sender and receiver, respectively.
The problem of picture tube nonlinearity has as-
sumed additional importance with the advent of color television. There, the display of constant hue regardless of brightness depends in alarge measure on the correct amount of gamma control in the color transmitter. Accordingly, the NTSC has included in its tentative proposal for color-television standards' the recommenda-
tion that the transmitter should employ a rooter network corresponding to areceiver gamma of 2.75 +0.25.
This design center is somewhat higher than the five-
halves power law assumed in earlier papers, and values for gamma of 3:1, and even higher figures, were quoted during recent sessions of the NTSC.
While most phosphors saturate at high energy levels, a linear relationship between light output and beam
current is reported5 for the lower current densities (<100 ga/cm2). Within this range it seems justified, therefore, to focus attention on the triode structure of

38, 3ppB..

M. Oliver, "Tone rendition 1288; November, 1949.

in

television,"

PROC.

I.R.E.,

vol.

3 Report by R. D. Kell, RCA. D. G. Fink, "Television Standards and Practice," McGraw Hill Book Co., Inc., New York, N. Y., pp. 189-194; 1943.

NTSC--Color Field Test Specifications, Supplement #75,

Telev. Dig., Wyatt Bldg., Washington 5, D. C.; December 1, 1951.

H. W. Leverenz, "Luminescence of Solids," John Wiley & Sons, New York, N. Y. Fig. 112, p. 358, pp. 349-362; 1950. Also G. F. J. Garlick, Elec. Eng., pp. 287-291; August, 1949.

1953

Schlesinger: Transfer Characteristics and Mu Factor of Picture Tubes

529

the cathode-ray tube including its cathode, aperturegrid, and first anode. A theory might then predict the form of the cathode-current versus grid-voltage characteristic and should reveal that this is indeed a simple power law. It should also yield the value of its gamma
exponent and indicate how gamma depends on the system parameters.
It should be borne in mind, however, that the beam current reaching the fluorescent screen of picture tubes is only a fraction of that emitted from their cathode. The electron-gun efficiency has a tendency to decrease at the higher currents because of increasing beam spread ahead of limiting apertures. This tends to reduce the gamma of the light-output characteristic below the value computed for the modulation section alone. A pertinent example is given in the experimental section of this paper.

conditions are met the over-all characteristic is apower law with a gamma of

-y = 3/2 + m.

(3)

It can be shown that the second condition is met if the potential gradient at the cathode surface decreases with the square of the radius off axis. This holds to a first approximation in axially symmetric fields, where the potential 17(,k) at any point is tied down to the
axial potential by the relation

r2

r4

= (th --

0(4)

(4)

4

64

The cathode gradient then reads

L grad V(0 ,,.) = 4,o) _

2<km

+

r4
4, (5)

4

64

. ··, (5)

LANGMUIR'S LAW FOR VARIABLE CATHODE AREA

The analysis that follows acknowledges the emission limitation imposed by space charge but it does not take into account its retroaction on the original field distribution in front of the cold cathode. The cold field is
found as a solution of Laplace's equation. Poisson's equation should be used at higher-beam currents. It has been found, however, that the simplified approach checks with experience up to a point where more than one-third of the total cathode area is active. This covers arange of current amplitudes most commonly encountered in picture reception.'
Thermionic emission in aconventional triode is pro-
portional to the 1.5th power of the grid-from-cutoff
voltage:

I= P[e g -- 4 312 ,

(1)

where P is the perveance constant.' Child's law may be re-written in terms of current density from asegment of
the cathode and the field strength E normal to it.

and since it vanishes at acritical radius rk,

O= grad 17(0,, )

=

rk 2 0 (3) ±

4·

· k 4 0(5)
64

(5(a))

\Ve obtain by subtraction of (5(a) )from (5),

0 (3)

4,(s)

grad V(0 ,,.) = (rk2 -- r2.) --4 -- (rk4 -- r4)--64 + ···,

or approximately grad V(0 ,, )

(PO

rk 2 -- r2

-- (0, 0)

4

(6)

The total cathode current may now be found by integrating the contributi-ns of concentric rings, each emitting under the influence of a field given by (6), out of the radius rk, where the field goes through zero. From (1(a)) and (6) we get:
rk
Ikok = kf [grtd VOA 312 27rrdr

= K·E'n.

(la)

In a tube whose cathode area is not constant, but depends on grid voltage, and where the field distribution across the cathode area is not uniform, the over-all
characteristic does not necessarily follow a power law. It will do so, however, if (1) The area function is itself apower law of the type

( 0(3)) 3/2
k -- 4

c rk (rk2 -- r2)312rdr.

A = const. (e, -- e9) m,

(2)

and if (2) The expression for the total cathode current takes the form of aproduct of (1(a)) and (2). If these two

ei Since this paper was prepared, a thorough analysis of the

cathode-ray triode including space charge effects has been published

elsewhere: M. Ploke, "Zeitschrift fuer angewandte Physik," Springer,

Berlin, pt. 1, vol. 3, pp. 441-449, December, 1951; pt. II, vol. 4,

pp. 1-12; January, 1952. The results of that paper are in perfect

agre7 eKm.enRt.

with those presented here. Spangenterg, "Vacuum Tubes,"

McGraw

Hill

Book

Co.,

Inc., New York, N. Y., and London, pp. 186-187; 1948.

530

PROCEEDINGS OF THE 1.R.E.

April

consists of an aperture 2R in aplane sheet of metal of thickness T, and a first anode A. For our purposes, there are four variables: d1, d2, /AK and R. We made the following assumptions:
1. The anode may be replaced by a plane through
point P connected to anode bias v..
2. On the surface of a coaxial cylinder through the grid hole the boundary potential has constant gradients between electrodes and assumes the values zero, V9,and V. respectively at cathode, grid and anode. (See Fig. 1(b)).
ded
GRID CATHODE STRUCTURE

shown in Fig. 1(c). To find an,we compute

an =

1

fo9 si n

lo(jrnR--) 1

If this integration is performed, we find that

irnan --

2

[V, sin (ra i)

R Io (jrn-l-)

ire

+ 82 (V 9 1-- 82

V.) + 62 (V9 1-82

V.) sin (rn82)] .(12).
71-11â2

Here, Si =- d2// are inter-electrode spacings in term of
system length /. We can now find the field strength normal to the cathode surface by forming &Paz in (9) and using (12).

r

V. grad ck(no) =--

2

lo(jrn--
R)/
Io(jirn--

V,sin (ire) irnS i

( )
BOUNDARY POTENTIAL )i.0

BOUNDARY DIFFERENCE
POTENTIAL

A 0'0a,z -- ve ·

Fig. 1--(a) Grid cathode structure, (b) boundary potential, (c) boundary difference potential.

The Laplace equation for axial symmetry reads

(V.

-- V.)· 62 1-- (52

sin (rn8 ra 2

2)]I.

(13)

At this point we may derive, as aby-product, aformula for the amplification factor 1.4, of picture tubes which is quite accurate.
µis defined as the grid cut-off voltage in terms of the first anode voltage,

=- -- V./Vc.

(14)

Cutoff occurs when the gradient at cathode center disappears. From (13):

E 0= Va 4- 2

1

[ sin (ra i)

Io(jrnR--)

ra i

+ 1 aé ay\ =0.
az 2 r ar\ Or!

(8)

(Vc -- V.) 82 sin (ire)]. 1-- 62 ra 2

(13a)

A solution which meets the above boundary conditions is

V.
443

Ean sin znz) ·/0 jKnr

/

1

(9)

Here, /0 is the modified Bessel function of zero order of the argument (rnr//). 8The coefficients an follow from a Fourier analysis of the boundary difference potential,

'4qt ,z = OR,z

Va . 1

(10)

·Tabulated in: Jahnke and Emde, "Tables of Functions," Dover Publications, New York, N. Y., pp. 226 and 228; 1943.

From (13(a)) and (14) there results

1-I- 2E
n1

1

sin (ra i)

Io (jirnR--)

TnZi

1 +

= 1

82
1-62

E 1

2

Io(jrnR/l)

sin (ra2)

(15)

Applications of this expression for practical tube types will be given later. We now proceed to our primary task
of finding the active cathode area as afunction of grid voltage. The radius rk of the active section is defined as the distance off axis for which the potential gradient passes through zero. From (13) for r=rk,

1953

Schlesinger: Transfer Characteristics and Mu Factor of Picture Tubes

531

E = V. + 2 10(jrnrk/1) [IT, sin (irnbi)

IoUrnR/1)

irn81

+

(V,

-- V«) 62 1-- 82

sin (rn82)1
7riu52 J

(13b)

By subtracting (13(b)) from 13(a) we obtain

V. -- V. Vg

1-- AF02
F01 ± AF02

1-- AFk2 = Go -- Gk.

Fkl +

F k2

(16)

In this expression, Fo and FAstand for

Fo = 2E

1

sin (Ira)

(17)

Io (jrnR--1)

rn8

indicate mu-factors within the limits of 3.9 and 9.1, around adesign center of 6.0.
In order to show how these constants depend on the mechanical dimensions of the gun-structure, the same analysis was repeated in three more cases, changing only one of the four parameters at a time. In case no. 2the thickness of the grid metal was reduced from 8to 4mils. In case no. 3the grid-cathode spacing was doubled. In case no. 4the grid diameter was reduced by 22 per cent.
--I> ACTIVE CATHODE RADIUS eit/R 0.1 ·--·····111· 0.2 0.3 04 0.5 rk/s
0.2%

0.3%

0.3

GRID - FROM- CUTOFF IN PERCENT OF PLATE VOLTAGE -m--

Io(jrnr k/1) FA= 2E Io(jrnR/1)

sin (7rn8) irttS

(18)

respectively, while

26- 45'
OC

0.4

BE TYPE 17GP4 ·TAN o2g.c5c018.008

0.5 0.6

08

=

d2

-- d2

62
1-82

(19)

Equation (16) contains implicitly the desired information about the active cathode area. To find the relation
rig =f( V.) we compute Go--GA for a few selected values
of rk/R and plot the results on double-logarithmic graph paper. If these points lie on a straight line this proves the existence of a simple power law between cathode area and grid voltage of the type anticipated
in (2). The exponent m is then found as m= 2·tan a. The factor 2accounts for the fact that the abscissa in Fig. 2is in diameter ratios, whereas m in (2) refers to cathode area. The over-all gamma of the tube is then found by adding three-halves to m, as called for by (3).

PRACTICAL APPLICATIONS OF THE THEORY

The expressions for µand gamma derived above were applied to a television picture tube type 17GP4. Numerical data for the four structural parameters listed in Fig. 1(a) were obtained from direct inspection of agun of this type, prior to its use on the production line. The standard data thus obtained were:

d1=4 mils, 1=8 mils,

R=18 mils, 1=40 mils.

Fig. 2 shows four points of (16) computed for active cathode radii of 1R/10 2R/10 3R/10 5R/10 respectively. All of these points lie smoothly on astraight line with aslope of 26° 45'. This indicates that the active cathode radius grows very nearly as the square root of the gridto-cut-off voltage. The area-exponent is 1.008, yielding an over-all gamma, for this tube, of 2.508. (See (3).) The µ-factor for the 17GP4 results from (15) as µ=5.9. Handbook data9listing the cut-off voltages for this tube

RCA Handbook, vol. 1-2, Tube Dept., Harrison, N. J.

%

APPLICAT ION OF

EQUATION (16)

TO FIND GAMMA

-EXPONENT

2

1

3
4 5

Go-Gk

6

10 %

10%

Fig. 2--Application of (16) to find gamma exponent.

The results of these analyses are summarized in Table I. The general trend seems to indicate that the µ-factor is affected by every one of the system variations, while on the other hand the value of the gamma exponent

TABLE I INFLUENCE OF SYSTEM PARAMETERS ON GAMMA AND MU

Analysis No.
1
2
3
4

Condition
standard tube type 17GP4 grid-metal thickness: 4mil [standard: 8mil] grid-cathode spacing: 8mil [standard: 4mil] grid-hole: 28 mil [standard: 36 mil]

ii-factor 7-exponent

5.9 3.17

2.508 2.46

9.6

2.34

11.9

2.41

seems to be remarkably stable. In fact, none of the structural changes seems to have much influence on gamma, which stays within 7per cent of amean value of 2.43. These results hold for atotal system length of 40 mils,

532

PROCEEDINGS OF THE I.R.E.

April

but they may be extended to any value of 1, using the principle of similitude" inherent in (15) and (16).
AN EXPERIMENTAL CONFIRMATION
In order to obtain an experimental check on the theory as outlined, an electron gun was built with the following data: R =18, d1=4, d2= 12, /=324 (mils). This tube was equipped with a separate collector electrode so that the actual beam current and the total cathode emission could be measured individually. Inserting the structural data into (15) and using 20 terms thereof to obtain better than 2per cent accuracy, amu-factor of 66.3 was computed.
The experiment revealed that cut-off occurred at --35 with afirst anode voltage of 2,400 v, thus indicating a mu-factor of 68.6. Measured data of cathode and beam current are plotted in Fig. 3on double-log paper, using the grid-fromcut-off voltage as ordinate. Both curves seem to follow simple power laws with a gamma exponent of 2.43 for the cathode, but only 1.9 for the collector characteristic. Guns with higher over-all efficiency may not exhibit as
10 H. Moss, "Advances in Electronics," Academic Press, New York, N. Y., vol. 2, pp. 32-36; 1950.

100

80

VOLT

60 GRID FROM

50

CUTOFF

40

30
20 «.'62"

pee

Ile

pe se

tee C>)

oot

--aIIIIIIIIIIIIIIIIIIZI

0

Gte

67" 4'

10
e
6
5

eCATHODE . TAN 67'40'
'BEAM. TAN 62 ° . 1.88

2 03

3 2

20

30 40

60 80 100

200 300

0AMP 500

Fig. 3--Characteristic of experimental tube.

much of a gamma reduction as the sample. However, the test serves to indicate that accidental electron interception within the gun may have astrong influence on the over-all transfer-constant of akinescope serving as a transducer from signals into light.

Optimum Linear Shaping and Filtering Networks*

RAYMOND S.BERKOWITZt, ASSOCIATE, IRE

Summary--Optimum transmitter and receiver transfer characteristics are obtained for linear communication systems under assumptions of fixed power levels and fixed over-all distortion of message signal. Two separate criteria of performance are used as the basis for optimization: (a) the mean-square value or variance of the receiver output noise component and (b) the probability that the noise component of receiver output exceeds a preassigned tolerance value at least once during some finite period of observation.
1. INTRODUCTION
i r 1HE PROBLEM considered in this paper is the . formulation of the joint optimization of transmitter and receiver transfer characteristics of a given communication system as illustrated in Fig. 1. The specific type of system studied is alinear one, in which the noise adds directly to the signal in the channel. The following quantities are considered as fixed:
1. Average noise power spectrum fl(f.o). 2. Desired message signal power or energy spectrum
S,,.(w).
*Decimal classification: R143.2. Original manuscript received by the Institute, April 2, 1952; revised manuscript received September, 1952. This paper is acondensation of aPh.D. thesis, which the author submitted to the faculty of the Graduate School of the University of Pennsylvania.
tMoore School of Electrical Engineering, University of Pennsylvania, Philadelphia 4, Pa.

3. The distortion present in the system between input signal and receiver output signal.
4. Transfer characteristics of the channel L(,). 5. Message signal power levels at all stages of the
system.

While the general problem of constructing networks to minimize the effects of noise has been attacked quite extensively in the literature,'-' the present work differs in the following respects:
a. Most of the previous work was concerned with constructing asignal filter to separate noise from agiven mixture of signal and noise, whereas here we consider that the signal itself can also be modified by asuitable linear shaping network at the transmitter.

1N. Wiener, "The Extrapolation, Interpolation, and Smoothing

of Stationary Time Series with Engineering Applications," Report of

the Services 19, Research Project DIC-6037, M.I.T., Cambridge,

Mass.; February, 1942. Also available as abook, printed by the Tech-

nology Press, M.I.T., Cambridge, Mass., and John Wiley and Sons,

New York, N. Y.; 1949.

3 R. B. Blackman, "The design of prediction circuits with data

smoothing," Bell Tel. Labs. Tech. Mem.; February 23, 1944.

3 R. S. Phillips and F. R. Weiss, "Theoretical Calculation on Best

Smoothing of Position Data for Gunnery Prediction," Radiation

Lab., M.I.T., Cambridge, Mass.; February, 1944.

ear

4 H. W. Bode and C. E. Shannon, "A least-square smoothing and prediction

simplified derivation of
theory," PROC. I.R.E.,

linvol.

38, pp. 417-425; April, 1950.

1953

Berkowitz: Optimum Linear Shaping and Filtering Networks

533

NOISE
min

TRANSMITTING f.(t) INTELLIGENCE

IRAN SHITTE-R ftft) Yiz ft.))

CHANNEL f3(t)
(L'")11

RECEIVER f4(t) Y34 (WI

RECEIVING INTELLIGENCE

Fig. 1

b. In previous studies signal distortion as well as that the Fourier transforms Fl(w) exist. We define r(t)

noise in the system output were considered as variables
subject to over-all minimization. The idea here is to obtain optimum filters that can be added to a given

and m(t) as the corresponding message components of the signals which appear at the input and output of the receiver, having Fourier transforms R(w) and M(u),

system so that the effect of the noise is minimized with-
out affecting the inherent distortion of the message sig-
nal. c. As adirect result of item babove, it is possible to
use as optimization criteria properties of the noise com-

respectively. Some basic relationships can be written down as fol-
lows:

F4(w) = Y34 (w)N(w) M (w)

(1)

ponent of the receiver output alone, rather than the usual mean-square error. In this paper two separate optimization formulations are obtained using the fol-

.1.3(1)= r(1) n(i) R(w) = M(w)/Y34(co) = Yr(w)Y12 (w)Fi(co).

(2) (3)

lowing two criteria. 1. The mean-square value or variance of the receiver
output noise component. 2. The probability that the noise component of the
receiver output exceeds a preassigned tolerance value at least once during some designated period of observation.
Which criterion would best apply to aparticular system is dependent on the mechanism by which the re-
ceiving intelligence converts the receiver output into

The assumption that the distortion in the system is fixed is equivalent for the linear system under study to
the statement that the ratio of M(w) to Fi(w) is aconstant, determined in practice by component design considerations. Hence, (3) gives us anecessary definite relation between the linear shaping network characteristics Y12 (w) and Y34(w). The procedure to be followed will be to use l'34(co) as the variable for optimization, Y12 (w) then being given by

information. Thus, if one's decisions are based on the value of the receiver output at specific instants, cri-
terion 1would be applicable. Criterion 2would apply

1

M(w)

17 12(w) = 1734(w)17c(co) Fi(w)

(4)

in cases where gated triggering is used, e.g., decisions being based on the maximum value attained during a fixed observation period. It can be shown that in certain cases the above criteria are in addition monotonically related to the equivocation or loss of information5-7 due to noise of such systems. Thus, while the optimizations to be performed are by no means aminimization of equivocation in the general sense, they can be thought

A constraint on the possible variation of Y34 (w) is imposed by the fact that the power levels of the message signal at the various parts of the system are assumed fixed by practical design consideration. This constraint is most conveniently expressed by the following equation for the power or energy of the message signal component at the input of the receiver:

of in these cases as giving the best results attainable within the limitations of the practical considerations
that are assumed.

1m

ir "

¡r -- Ar. 27r _w

w)/Y342(co)dc0, 8

(5)

where

2. GENERAL CONSIDERATIONS

Consider the block diagram of Fig. 1. We assume that the messages transmitted fi(t) are of finite duration so

m = f Sm(w)dco,
2 -w
W = maximum angular frequency of message signal

C. E. Shannon, "A mathematical theory of communication," Bell. Sys. Tech. Jour., vol. 27, pp. 379-423, 623-656; July and October, 1948.
·C. E. Shannon, "Communication in the presence of noise," PROZ. I.R.E., vol. 37, pp. 10-21; January, 1949.
7 R. M. Fano, "The Transmission of Information," Research Lab. of Electronics, Technical Report No. 65, M.I.T., Cambridge, Mass.; March 17, 1949.

and Arm =-- power gain of receiver.
8 Note that "Y(w)" not underlined is used as the magnitude of

534

PROCEEDINGS OF THE I.R.E.

April

Po ,the variance of the noise component of the receiver output, is given by

1 *3

Pno = --271- f Y342(w)-S-n(w)dco,

(6)

exceeds some given tolerance value at least once during agiven period of time. Here we assume that the noise is Gaussian.
There are two ways in which the tolerance value can be exceeded during the observation time:

where

.3,,(co) = average spectrum of noise.

3. NOISE VARIANCE M EASURE
For our first measure of system performance, we proceed to find the receiver transfer characteristic magnitude Y34(co) that will minimize Pno and still satisfy (5). In the first place, it is evident that Y34(w) should be zero for co greater in magnitude than W. Using standard variational techniques,' we obtain for 14 < W a value Y34 '((o) that yields minimum output noise variance, as outlined in Appendix I. The result is

a. The noise is greater than the tolerance value for the whole of the observation time.
b. The noise passes through the tolerance value at least once during the observation time.
We assume in this discussion that the former contingency is not significant due to the duration of the observation time. This is done because of the mathematical difficulty involved in accounting for both contingencies. Thus the problem reduces, at least approximately, to minimizing the expected number of positive slope crossings per unit time of the tolerance value, given by the expression°

Arminns

1734"(W) =

1/Sm(C0)/Sn(W),

(7)

1V --Ipo"

Ed -- 2r

4,0 exp (--d2/21,4),

(10)

where

where

1 w

= -- f VS.(co)S,,(co)dco. 2r .__Tv

(8)

4/0= --1>T31(w)dw = Pno
2ir

(11)

The expression for the resultant minimum variance of the receiver output noise is

----1f .2.3.(w)d.

(12)

2r ,

Pn0 1= ArmInnt 2

and (9)

S(w) = 1e842(co)3,,(co), or zero if Ico I> W. (13)

It will be noted that this optimization places no restriction on the phase angle of the receiver transfer characteristic. An important feature of these results is the fact that the optimum shaping and filtering networks obtained in this manner are independent of the amplitude of the channel noise, being dependent only on its relative frequency distribution.
Several examples of the application of the above results are shown in Fig. 2. In the first two columns are shown some representative combinations of signal and noise spectra. The parameter x is the ratio of co to W, the message signals' maximum angular frequency component. The resultant optimum magnitude of the receiver transfer characteristic is in the third column. The last column shows the ratio of the minimum value of noise variance obtained to the value which would result if the receiver characteristic were flat in the pass band. As expected, the relative improvement increases as the linear correlation of signal and noise spectra decreases.
4. PROBABILITY TOLERANCE M EASURE
The second type of measure to be applied is the probability that the deviation at the receiver output

[v. (o] a

I 5.,,,,(i...»ARBITRARY (NoIENno?se ) ARDITRARY

a S... ((..))8881TRARY 38..1)...k. SmuCre»

3

.'le

4

0.

a.a
l

o

ci --e)1
0 ot.

a.t

0L(
L

I-re)

5

4/..

o.1 e c-4.)a
6

I

tai ea
1 i 'e-
ea. 2- l
i.e.
I.
,,,, a z
it nu

A/vra ,.· CON ST. 4.-ki,ent 1F/7.

3

(i -e.)

a7l5*-Aiten,

iAAnn· le i

Fig. 2

Pm.10/P.."..c.
NONE
1 13-=.889
21-- ='a5

As before, we set 1734 (co) equal to zero outside the message band. Applying variational techniques' to find extremes of Ea under the constraint of (5), we obtain (see Appendix II) results as follows:

9 H. Margenau and G. M. Murphy, "The Mathematics of Physics and Chemistry," D. Van Nostrand Co., Inc.; New York, N. Y., chap. 6; 1943.

10 S. O. Rice, "Mathematical analysis of random noise," Bell Sys. Tech. four., vol. 23, pp. 282-332; July, 1944; vol. 24, pp. 46-156; January, 1945.

1953

Berkowitz: Optimum Linear Shaping and Filtering Networks

535

rw 1.1(u) = 1

Sm(c0)3.(w)

r io

uzwz wz

f%.,2 /sm(w) n(w) I2(u) = 7r jo

Av 3 u2,,2 4. 1,172 dco

will cross the value dvery seldom, the magnitude of the noise will be greater than dmost of the time.
In any event, it turns out that the solution of d' 2=d2 for which the value of u is smallest is the one that should be used as adesign value.

/3(u) = d2 =

f W N/Sm(C0)3n(C0)(14 2CO 2

71"

o

d' 2(24) =

Ii(u)I32(u) u2I2(u)I,.

1172)dco

Y342(w)

/3(14)

Sm(W)

Ir Vsn(w)(142,,2 -1,172)

TABLE I

Quantity

S.(0) .7,,(0) k>0

e0

approaches co as log 2u

eI,. finite limits

s,,,(o).§.(o) =o

u--.0

finite limits

finite limits, system equivalent to "minimum noise variance" system

For aspecific problem, it is first necessary to obtain numerical expressions for integrals /3,/2,and /3in terms
of the parameter u. Then it is necessary to solve expression (17) for u in terms of d, the deviation tolerance value. Using this value of u, the "optimum" value of Y342(co) is given by (18). It is seen that this value differs

Ed approaches zero as 1

Vlog 2u

d'2

approaches co as log 2u (becomes equal

approaches the same finite

approaches co as 1/u2

to 1,e0)

limit as #0

from the previous result which simply minimizes the noise variance, in the inclusion of afactor u2w2-1- W 2 in
the denominator. This factor tends to deemphasize the

We take as an example the case of constant signal and noise spectra. Thus,

higher frequency components of the noise, thus decreas-

Sm = a2; = b2,in -- W < co < W

(22)

ing the likelihood of short pulses exceeding the tolerance

value.

d' 2(u), Y342(w), 1P 0and 11/0"are as follows:

The crux of this method is the solution of (17) for u in terms of the tolerance level d. It is necessary to plot
d' 2(u) given by (17) versus u, then to select graphically the desired solutions, at which d' 2=d2.This of course has the advantage that we can use the same plot for a variety of values of the tolerance d.
Resultant expressions for #3,4/0", and the value of Ed,all expressed as functions of u, which result when the receiver transfer characteristic magnitude is given by
expression (18), are as follows:

v(sinh 2v -1- 2v) 2 d' 2(u) = PnArm 4sinh 2v(sinh 2v -- 2v)

sinh 2v -1- 2v

W

Y342(co) = Ar. 4sinh y Vu2w2-I- W 2

IPO = PnArm

sinh 2v -I- 2v 4sinh2

-- 1h" = W 2P.A.

sinh2 2v -- 4v2 16 sink'

(23) (24) (25) (26)

=/3(u)/3(u)

Ir

_44, =

/2w/8 w
Ir

1 4/ /2(u)

--d21,.

Ed -- 27r

ii(u) exp 2/3(u)/3(u)

Examination of the above expressions enables us to draw certain inferences as to their behavior when the
parameter u varies. These are outlined in Table I. In the case where S,,,(0)3,.(0) =k>0, we see that d' 2
approaches infinity for both of the limiting extremes of u. Hence, the equation d" =d2 (solving for u) must have in general an even number of solutions. If d2 is less than
some minimum value, there is no solution. These solutions signify the extreme values of Ed. Now we know that Ed is finite for u=0, zero for u-->oo. Hence, the solutions of d' 2=d2 will be alternate minima and maxima, the first being a minimum and the last being
amaximum. For system design purposes, the fact that Ed--> 0 as u--> oo is not significant, since in this case 4/0 becomes infinite; this means that while the noise signal

b2W

= sinh' u, P. =

(27)

ir

For a given tolerance value d, optimum design values of uor vare obtained by solving the equation d' 2(u) =d2. For this example, this process is illustrated by the curves
on Fig. 3.
e., Here we have normalized plots (on a log-log scale)
of d' 2, and --#0"40,as functions of the parameter v. The value of d' 2,starts out at infinity, then passes
e. through a minimum, after which point it merges with
the curve. If the square of the tolerance value d is less than about 1.6, the value of this minimum, the expected number of crossings Ed will have no extreme
value. For values of d2 greater than this minimum, two values of ywill satisfy the equation d' 2=d2,the first being aminimum and the second amaximum.
On Fig. 4we have plotted the variation of Ed with y for two such values of the tolerance parameter d, namely d2=2.0 and 2.5. In both cases, Ed is seen to be-
come aminimum at the first point where d" =the given value of d2 on the graph of Fig. 3. We can call this the "optimum" value of yin each case since, even though Ed

536

PROCEEDINGS OF THE I.R.E.

April

becomes smaller than this minimum value for sufficiently large values of y, we will remember that the variance of the receiver output noise 4, 0 is considerably larger than our tolerance value (12 at these values of v. Hence, Ed is small only because the noise signal is greater than the prescribed tolerance most of the time,
an undesirable error-producing result. Returning to Fig. 3we see that the optimum or de-

Io
500

200

100 ASYMPTOTE: 3

50

V2

..--

Pn

d' 2 Arm

\I\

20

\ ASYMPTOTE:

1 100

10

·iri

.-- --- ·--100 lo W2
ASYMPTOTE: -21-V

5
2.5 2.0
lo .Pn Arm · 1 ASYMPTOTE:

V · I.26..

DESIGN /i- VALUES,

V .1.55"-r

ASYMPTOTES I .100
2V w2

Y34 '(CO) into (6) gives the extreme value P,, 0'given by (9). To show that this extreme, being unique, is a mini-

mum, we compare Pno 'with P,, 0", the noise variance which would result if Y34(co) were constant in the band --W<co<W.

This yields

Fflo ,
p no lt

2 S m (CO) n (W)d,}
{f: 3 W3.(w)(10.) f-w

(30)

By Schwartz's inequality," this ratio is always less
than or equal to unity. Hence the unique extreme value Pno' must be aminimum.

1

1--

1-

YMPTOTE:

da

0.212

`'Pn Arm 2.0

·

·I.55

.20 ASYMPTOTE:
· 0.165

d2 Pn Arm

2 5

V.1.2

DESIGN VALUE

.10

.I1

.2

V

.5

I

2

Fig. 3--Design curves.

5 10

sign value of yis the smaller value at which the d" curve crosses the specified value d2.It is seen from the Ed curves that the decrease in Ed from the minimum noise variance case (y =u=0) is rather small. This will usually be the case. Such an optimization device will usually be practical only for those marginal systems where every last ounce of performance possible is needed.

APPENDIX I
Derivation of Results for Minimization of Output Noise Variance

The "optimum" receiver characteristic magnitude of (7) is obtained by determining the minimum value of
Pflo (6) using (5) as a constraint. Applying variational techniques' we find that PK,is extreme when

3,,(co)Y34(w) -- kS.(w)/Y343(5.%) = 0

(28)

for all co less than W. We designate this "optimum" value of Y34 (co) as Y34 i(co); kmay be determined from (5) as being given by

Nik = ,./..//n%;

(29)

thus expressions (7) results for Y34'(w). Substitution of

2

10

Fig. 4--Ed versus y. d2/P.A,.,,,= 2.0, 2.5.

APPENDIX II
Derivation of Results that Minimize Expected Crossings of Given Tolerance Value
Here the procedure is to find extremes of Ed (10), again using (5) as aconstraint.' Equating the variation of Ed to zero, we obtain, after eliminating common factors,

%Po 28io" (d2 -- 1P0)11,0"(311/0 = 0.

(31)

Using (11), (12), and (13), this becomes

fow (A

B)3,,(co)Y34 (w)(31734 (w)do.) = 0, (32)

1% H. Cramer, "Mathematical Methods of Statistics," Princeton University Press; Princeton, N. J.; 1946.

1953

Mostafa and Gohar: Characteristics of Single-Layer Coils

537

where A and B are positive constants, independent of

co, satisfying
A=

B = -- ip."(d2 --to.

(33)

Introducing the constraint of (5) on the SY34(co), there results
(Aw2 B)3,,(co)1734(co) -- XS,,,(w) /Y343(co) = 0 (34)

which must be satisfied for all Icol < W.

From here on, the algebra consists of substituting

1734 (co) as determined by (34) into (5) to determine X, then the use of (33) to establish values for A and B in terms of the known quantities. Defining the parameter

u by the equation

B = A2w2/u2,

(35)

(17) and (18) result, where /1(u), /2(u) and /3(u) are as determined by expressions (14), (15), and (16).

Determination of Voltage, Current, and Magnetic Field Distributions together with the Self-Capac-
itance, Inductance and HF Resistance of Single-Layer Coils*

ABD EL-SAMIE MOSTAFA t, SENIOR MEMBER, IRE AND M .K .GOHARt

Summary--A theoretical investigation for quantitative evaluation of voltage, current, and magnetic field distribution along single-layer coils is presented herein. The magnitudes and the number of harmonics present in the distribution are obtained for the first time. From the voltage and current distributions, the self-capacitance and inductance of coils have been obtained. The self-capacitance depends mostly on the length to diameter ratio; it slightly depends on the amount of harmonics as well as the pitch to wire-diameter ratio. The harmonics mainly rely on the number of turns, the operating frequency, the coil diameter, and the length to diameter ratio. From the magnetic field distribution, the HF coil resistance is obtained. Experimental results extracted from previous authors are in good agreement with the theoretical predictions.
I.LIST OF PRINCIPAL SYMBOLS
a=mean coil diameter, cms. b=coil length, cms. D =distance between adjacent turns (pitch), cms. d=wire diameter, cms. N =number of turns of coil. Le=coil inductance, µH C,, =coil self-capacitance, cms. (e.s.u.). R,10 =dc resistance of coil. R.=ac resistance of coil. co/27r =operating frequency. co,./27r =self-resonant frequency of coil.
II .INTRODUCTION
A great deal of theoretical and experimental work has been published concerning HF single-layer coils.
*Decimal classification: R382 X R217.11. Original manuscript received by the Institute, December 28, 1951; revised manuscript received September 5, 1952.
1.Faculty of Engineering, Alexandria University, Alexandria, Egypt.
Electrical Dept., Fouad IUniversity, Giza, Egypt.

The most important published comprehensive theoretical work for the determination of HF coil resistance is due to Butterworth.'-3 His main formula for single-
layer solenoids of very many turns is

R./ = a(1

(Oui

d2 yu2) --DG2.

F and G are functions of tand t2=271-2fuelp; u1and u2 are functions of bla, and pand µare the resistivity and the permeability of the wire material, respectively;
a, 13, and 7 are functions of d/D and t. All are tabulated in Butterworth's paper. Afterwards, Butterworth modified his formula to suit very short coils as follows:

= 1 F(1 + --1 W .d4\ 8 DI

U,,G D1(2-2 (1+ 2

D2

where, U., V,,, and W. are functions of N, and cbi is a function of t. Butterworth did not consider the case where the current is not uniformly distributed along the coil. Butterworth's formulas are also not suitz:ble
for coils of intermediate lengths, which was clearly indicated experimentally by Jackson. 4 Unfortunately,
most HF coils are of intermediate lengths.

S. Butterworth, "Eddy-current losses in cylindrical conductors, with special applications to the alternating current resistance of short coils," Phil. Trans. (London), A 222, p. 57; 1922.
2 S. Butterworth, "Alternating current resistance of single layer Proc. Roy. Soc. A., A 107, p. 693; 1925.
'S. Butterworth, "Effective resistance of inductance coils at radio frequencies," Exper. Wireless and Wireless Eng., vol. 3, pp. 203,
302, 417, and 483; 1926. W. Jackson, "Measurements of the high frequency resistance of
single layer solenoids," Jour. IEE (London), vol. 80, p. 844; 1937.

538

PROCEEDINGS OF THE I.R.E.

April

According to the authors' knowledge, there are no previous publications which give the voltage, current, and field distributions along HF coils. Howe,5 in determining the self-capacitance of single-layer coils, assumed the current distribution to be a sine curve superposed on a rectangle. He mentioned that the calculation of the magnetic field even with this assumption is practically impossible. Palermo,' in deriving his formula for the self-capacitance of single-layer coils, considered only the capacitances between adjacent turns to be responsible for the charging currents. He did not contemplate the capacitances between the different turns and apoint in the coil estimated at zero potential which form the important portion of the self-capacitance. Palermo's formula is
D C. = Ira/3.6 cosh-1 -- umf.
d
Medhurst7 showed experimentally that C. is practically independent of the spacing ratio Did for acoil having b/a=1.0
Recently, Moullireo attacked the problem of an infinitely long solenoid in which the current flow was circumferential and had a density which varied harmonically along the axis. Using Bessel functions, he then calculated the self inductance of single-layer coils.
III .CURRENT AND VOLTAGE DISTRIBUTIONS
In calculating the current and voltage distributions along the coil, it is assumed that the ac resistance of every turn and the conductance between turns are negligible. It is also assumed that the interaction of

electric currents in the different turns is instantaneous, which is very approximately true so long as the coil dimensions band aare small compared with the wavelength in free space corresponding to the operating frequency. Accordingly, the currents in the different turns will be in time phase.
Steady sinusoidal conditions with respect to time will be assumed. Symbolic notations will be adopted. Rootmean-square values will be used.
We are going to consider first the case where the coil is not earthed at either end; it may then be earthed at its center.'°
The charging currents are those shown in Fig. 1. There are other charging currents between adjacent and nonadjacent turns which are very small and can be neglected. This is clarified in Appendix A.

A. Calculation of Potential Due to Magnetic flux Consider aturn at adistance xfrom center (Fig. 2).

tx

-0.0.0 E>80-00

0-El>19 GO Gq) eGéOG--

.

I

j

j

j

ibeeeee-eeee-eeee-e-tteese-e

-- 1"-

!-----4:--

iI.

z -

i-

b

! 1
.--i

Fig. 2

+ +)

# e C0

)

Let the current in that turn =ix,its charge =q, and its potential with respect to the coil center (considered of

`. `e, ·'C.) zero potential) =v. The current in the adjacent turn

L.1.

distant x-FD equals i.-1-Ai=i.-1-jc.aq, giving

q = Aifico = (Daw)di/dx.

(1)

a.
C4
HI

o=a

H-o

I

P/4« · Sore Pele.lna(

Cc ·iL c.fre)

Fig. I

G. W. O. Howe, "Inaugural address to the wireless section," Jour. IEE (London), vol. 60, p. 67; 1922.
SA. J. Palermo, "Distributed capacity of single layer coils," PROC. I.R.E., vol. 22, p. 897; 1934.
7 R.G. Medhurst, "H.F. resistance and self-capacitance of Single Layer Solenoids," Wireless Eng., vol. 24, pp. 35 and 80; 1947.
8 E. B. Moullin, "The field of a coil between two parallel metal sheets," Jour. IEE (London), vol. 94, p. 78; 1947.
E. B. Moullin, "The use of Bessel functions for calculating the self-inductance of single layer solenoids," Jour. IEE (London), vol. 96, p. 133; 1949.

The potential of the adjacent turn =v-FAv, and Av

Ddv/dx =voltage drop across a turn at adistance x.

Thus, Av =voltage drop due to the turn's self-inductance

/-Fsum of voltage drops due to the mutual inductance

E mi.. M between the turn in question and any other turn of

the coil =judix-Fjca

(2)

Maxwell's formula for the self inductance of a sin-

gle turn is

1= Zra (1 + --136 (17,2,)

1 d

- (2+ --16 --a22)} Xµ1H0.-3

(3)

The mutual inductance M between two turns distant zapart can be obtained from tables in footnote refer-

lo The case where the coil is earthed at one end can be directly obtained, and it is given in Appendix C.

1953

Mostafa and Gohar: Characteristics of Single-Layer Coils

539

ence 11. Plotting Mla to abase of y/a and remembering that M(y)= M( -y), Fig. 3 is obtained, where y is the distance between the two turns which require M. The interesting values of Mict are those starting from y=D. At y=0, the ordinate is lla. The summation in (2) should be carried out turn-by-turn. However, unless the
number of turns is small, the same result can be satisfactorily obtained by an integration process. Therefore,
(2) reduces to

iCsdi x

612
f Mi.dz D x+D

4.1

bI2

= j

f

D

--b/2

lizds

f_--

M izdz

D

b/2

(4)

where nis an odd integer. The upper limit of the summation will be given later in the paper. A convenient representation of the characteristic, Fig. 3, is a trigonometric polynomial by means of Fourier analysis with 2b/a as its fundamental period.

E M i/a = Ao

A. cos (mry/b).

(6)

The upper limit of the summation in (6) depends on the number of terms in the expansion required for satisfac-
tory representation. A0 and A. are to be determined
from Fourier analysis. It is clear that Aoand A. depend on D/a, b/a, and dia.
In order to have the same M ila->y/a characteristic for all practical coils, a value of 0.005 for Dia and a value of 0.01 for dia will be assumed. For other ratios, the representation of the characteristic will be prac-
tically unaffected (Appendix B). Fig. 4 shows a chart of A0,A 1,A2, and A.3 against
b/a ranging from 0.25 to 2.5 including almost all practical coils. Substitution of (5) and (6) in (4) gives

1

`it

D/4

Fig. 3

Y/1 1

M 1 is the curve 122' 3' 34 (Fig. 3). From the nature of the problem, i, can be repre-
sented as

= ao +E a. cos (nrz/b)

(5)

dv

Av=D --

dx
fri, b a
=jwao --D --v.

E {21 0+
0-_, 12

A. COS 1/1(0 -- CI (10

f./2 E -Ho

b a --ir

[(

0, 12

Ao

a. cos nO)

+E an2A {cos ((m n)O - m4)

+ cos ((m -1)0 -m<b)}]dO,

(7)

It id ¡ 5
A.
9
5

where 0=7i-0, 4)=rx/b, 0-0= r(z -x)1b=ry/b. The first part of (7), which is

E (b/D)(2a/r)(-2-A0 +

A. j^-1 -- cos nrx/b)

gives the inductance m0 between aturn at adistance x and all other turns of the coil, the integration of which along the coil gives L..

E 2 Le =D- b2 - 4.7a,2(i--r42 A0+

A./ n2) H.

(8)

3
At
A,

0.5

1.0

Fig. 4

10

25

Tt:

11 F. E. Terman, "Radio Engineering Handbook," McGrawHill Book Co., Inc., New York, N. Y.; 1943.

b/a 0.25 0.50 1.00

TABLE 1

L,/N'a (Authors') 1.419X10-2 1.019 X10-2 0.65 X10 -2

Lz11V2a (Nagaoka) 1.435X10 -2 1.035 X10-2 0.697X10'

Discrepancy per cent 1.14% 1.60% 4.25%

L. is calculated by (8) for several coils having different dimensions, and the results are in good agreement with those of Nagaoka (Table 1). Integration of (7)

540

PROCEEDINGS OF THE I.R.E.

April

gives,
b2 y= jo,
D2

Ej-1 - ao

x

7r 2 {TM ° --b +

2
rtl

A ,, sin nfb}
n2

E + jc0

--b2 --aR2A 0

D 2 r2

n..1

i n-1

an)r x --n --b

± ,{ E a.

jrni-n-1

A.

sin m4

,.1

rrtl!

n) tn(nl +

(m4 n /Odd

E Ei n-i + { an

n-1

m-2

Am M(M --

n)

sin nut}

("'" odd

E +

{--7r 2 ,i-i

a,,A,,, m

sin m40}

·

(9)

If the current were uniformly distributed and of value ao,the potential would not be uniform and would be

given by

b2 a

Tx

, A.

y =

iC011o

D-- 2

--7r

{TA
2

o --b

+

20L-,1

--n2

jn-Isin

(nirx/b)}

.

The voltage at the coil end is obtained from (9) by
putting 0=2r/2. The terminal voltage V,,, is twice the end voltage,

winding is of the order of the wire diameter. The charge distribution on the cross section of any turn is mainly due to adjacent turns; nonadjacent turns have practically
no effect due to the screening action of the adjacent ones. Any turn, except the central one and the two end
turns, can therefore be satisfactorily considered as if it were acentral wire of three equidistant coplanar long wires having nearly the same charges, neglecting second-
order effects. The charge in the central wire will therefore be considered as if it were concentrated at its center. There is practically no charge on the central turn
of the coil. Therefore, the potential due to any turn of the coil except the end turns could be calculated as if it were an isolated charged ring. It is clear that correc-
tion for the two end turns must be carried out if the number of turns is very small; such correction is evidently dependent on the pitch to diameter ratio. How-
ever, for alarge number of turns, the correction is very small and the potential distribution as well as the selfcapacitance C, will be practically independent of pitch
to wire-diameter ratio. Following the same lines as in part A of this section,
the potential yat a turn distant x from the center is given by

Vter = iC0a °Le

E b2 a

D iCt1 2

7r

al

i n-1

(2Ao na l

±

An).

(10)

2

1 { f 1'12

x-ED

v= -- --

pK(p)qdz -- f pK(p)qdzf

ra D

-b/2

x--D

B. Calculation of Potential Due to Electric Charges

The potential at the point P due to a ring having a charge q(Fig. 5) is given by

VP

=

for ai _o

qda i

± a s)

a 2 cos '? al /2

2p
-- q
ira

212

2

N/1

--

p2

= cos 2-y i 7ra

qpK(p),

(11)

where

it = a7/ 2 ,

p= i/v1+ y 2/a 2,

and K(p) is the complete elliptic integral of the first
kind with modulus p.

+ potential due to charge on turn under question. (12) Equation (12) can also be reduced as in part A to

2 1 bi 2 = -- -- f pK(p)qdz.
ira D _biz

(12a)

Using tables of footnote reference 12, pic(p) can be
plotted to a base of y/a in the same way as 21la in

part A.

Therefore,

pK(p) =Bo+ E B. cos (Inlry/b)

(13)

where Bo,B. are to be determined from Fourier analysis. Fig. 6shows achart for B1 against b/a.

1 26

6

0/2

1 2

Fig. 5
It should be noted here that the charge on any turn except the two end turns could be considered satisfactorily concentrated on a circle, even if the pitch of

0.25

0.5

10

125

a
Fig. 6

15

175

20

Data," Macmillan 12 H. B. Dwight, "Mathematical Tables, and Other Mathematical Co., New York, N. Y.

1953

Mostafa and Gohar: Characteristics of Single-Layer Coils

541

Substitution of (1), (5), and (13) in (12a) gives

-- E 1 2

7r

{-

wt.& sin

jco Ira

2

+E na. E in+ m-1 B. sin In41)

n..·1

m-2,4. ···

In n

--E nao E irn--n-1 B. sin m4 .

m-2,4. ···

m -- n

Terminal voltage

E 1 2
= 2v(0 = x/2) = - --

jn-i na.B..

ico a

(14) (15)

The coil self-capacitance, therefore, depends mainly on
Ao,A1, As, As, ···B1 and Bs, BS,. ,located on the
coil length to diameter ratio. It depends slightly on the harmonics present, which latter rely on the length to diameter ratio as well as on N, provided the frequency =cor/27r. For any other frequency, the harmonics de-
pend also on the operating frequency co/27r and on a. For the coil along which the current distribution was previously given by (16), the effect of harmonics is to
increase Coby about 2per cent. The self-capacitance depends slightly on the fre-
quency at which measurement is made. Medhurst7 reported, in Table 2of his paper, the following measure-

IV.DETERMINATION OF M AGNITUDES AND NUMBER OF HARMONICS

The two potentials due to magnetic flux and electric charges must be equal at any turn of the coil. Therefore, (9) and (14) are equal at

N-- 1

b

x= 0, x= D, x= 2D, ···,x= 2 D

2

There will be (N-1)/2 equations giving (N-1)/2 harmonics in terms of the input current ao.Therefore, the harmonics in (5) must not exceed (N-1)/2. From these (N-1)/2 simultaneous equations, ai/ao, as/ao, ao/ao,
···,aN_2/a0 can be obtained, and it is clear that they depend on b/a, co/27r, a, and N. Calculation for a coil having N=13 and b/a = 0.5 gives A0=0.751, A1=0.643, A2=0.2855, A3=0.2085, A4=0.1426, Bo=2.811, B1 =1.217, B2=0.406, B3= - 0.0128, and B4=0.172. When the coil is resonating (a o=0), the current distribution is
iz = ait cos (7rz/b) - 0.0628 cos (37rz/b)
0.02 cos (57rz/b) -I- ···1. (16)

It is clear that the magnitudes of the harmonics are small and the series forming them is convergent.

V.DETERMINATION OF COIL SELF-CAPACITANCE
When the coil is self-resonating, ao=0, and co =
al =1/N/LoC-.. Equating (10) and (15) and putting ao =0,
and =cor2=1/L,C,, gives

a
C = 2

E

(2A 0 -I- A.)

nal

4

E r2
4 A O+

A,,/n 2

E

a,, B.

as

(2A 0 -I- AI)- -- (2A 0 -I- As)-I- ···

ir

3a1

4
a
2

7r 2 --As + Al
4

A 3 + ···
9

as B1 -3--aiB3 + ···

(17)

Experimental Authors' Butterworth

TABLE 2
b/a =0.625, d/D=0.745 f=1000 kc,
d=0.1016 2.71 2.74 3.32

b/a =0.333, d/D=0.652 f/=800 kc,
d=0.0508 1.795 1.765 2.00

ments: At Frequencies between 0.72 and 3.0 mc/s, the self-capacitance ranges from 2.14 to 2.17 uuf; however, at frequencies between 6.0 and 18.0 mc/s, the selfcapacitance varies between 2.27 and 2.37 uut (the
natural frequency of the measured coil was about 15.0 mc/s).
If the harmonics were neglected, the coil self-capacitance could be obtained from (17) by putting (4=0 =ao= ···.In this case,

C, =

r a
8B 1

7r 2
-- Ao 4

2A0 +A1

A 3
AI+ -- 9

AS --25 + ···

a 2b2

1 2A0 +A1

D2 27rB i

Lo

(18)

Equation (18) is a satisfactory one for calculating the

coil self-capacitance, provided the number of turns is

not very small as stated before. Equating (10) and (15)

and putting as=0=ab= ··· and using (8), the fundamental component, al of the current can be satisfac-

torily obtained.

Le

0 1) al=

ao (u,2

) a b2

-- -- 1-- 2 (A ± A

co'

7r LP

(19)

VI .M AGNETIC FIELD DISTRIBUTION
At any turn along the coil, there are two magnetic fields, the self-produced field which is due to the current in the turn itself, and the mutual field which is due to the current in the other turns. The latter may be resolved into two components, axial and radial.

4. Self-Produced Field
If a unit current is flowing in a certain turn of diameter a, it will be accompanied by a flux tte linking

542

PROCEEDINGS OF THE I.R.E.

April

the turn. Assuming a to be increased to a+Sa (Fig. 7(a)), d) will therefore be increased to d.+46. The selfinductance twill also be increased to 1+51, where

Sa SI = 54) = ira--B, 1
2 and
2 dl B,,= i--ra --da = self produced magnetic field due

to unit current. It is considered axial. The mean value of

1

1 dl

B, 1 = Ba1mean = 2 -- /381 = r--a -- da·

It is acting over the cross section. The self-produced field due to current iflowing in the turn under consideration will, therefore, be given by

B .

i dl =-- -- ·
ira da

(20)

The value of dl/da is obtained from (3).

B. "Axial Component B,," of Mutual Field
Consider two turns distant y apart and having the same diameter a (Fig. 7(b)). If the diameter of the

Substitution of (6) gives

B,, -- i 2id(aA 0) 2 7ral da

E

d(aA,,,) da

cos

} (miry/b»..

(21)

It should be noted that d(aA,,,)/da is afunction of b/a · only, since

d(aA.) = da

b dA n. a d(b/a)

-1

1.2
I. O 0.8 0 04 02

(fi 4. )/da A,Vd+
80a 012)/04.

4 4

o

0.5

1.0

1.5

2.0

2

Fig. 8

Fig. 8shows achart for

d(aA 0) d(aA 1)

(4

(c1

da

da

against b/a.

turn at which the field is required is increased to a-I-Sa, the axial flux linking this turn due to a unit current
flowing in the other will be increased from it to ck,-F(5(1),,.
The mutual inductance will therefore increase from M to M-I-8M, where

giving

dAf

= (3e,

=

Ira

Sa
--

2

2 dM B1,,= --ira = --da = axial field component

due to a unit current passing in the other turn. The
mean value of Bii,(=P li,) gives the axial field component acting on the cross section.
If acurrent iis flowing in the other turn,

.= 1 2i dM 2 ra da

--1 2i dMi 2 ra da

C. Radial Component BR of the Mutual Field
Let the turn at which the field is required be displaced axially a distance Sy (Fig. 7(c)), the mutual radial flux due to a unit current flowing in the other turn will be decreased from Cht041R--t14)R.The mutual inductance will be reduced from M to M-- 8M, where

-- SM = ray ·BiR,giving BIR = -- --1dM/dy. ira
The radial field component due to acurrent

iin other turn = BR Substitution of (6) gives

-- --i dM ra dy

i dM ira dy

BR = i

sin (mry/b).

(22)

b m-i

From (5), (20), (21), and (22), and by following the same lines as in part (3), the axial and radial magnetic field components B1,and BR,, respectively, acting over

1953

Mostafa and Gohar: Characteristics of Single-Layer Coils

543

the cross section of a turn distant x will be given by
r 1 1 2 1'12 dM
B. 5= -- 2 -I)- --Ira .1 --b/218 da dz

1

"

skin effect = W. = -- f i,22raR0(1

D --8/2

Substitution of (5) for ix gives

F)dx.

= ao _2 b 2 {r d(aA o) 2 2r2 a D 2 da

W. = a02{1 --4

an

7r

nap

 E

1 d(aA n)cos n<4 n da

+ 1 2 b 1[{ d(aA o) ------ 2

--an sin --

- 71-2 a D

n-i n

2

J
+ IEanE n=1

d(aA,,,)

da im+n-1 cos tne

m n

m even

d(aA ,,,)

+

E anE
n.4

da

im-- n-1 cos tn(1)

/Pt

n

Jmeven

+ ·E an d(aA,,,) cos /no}

(23)

· e.»1

da

m=n]

and

= --1f 8/2 iz {--1 EmA,,, sin (mow z

dz

D --8/2

b ,n-2

E 1
= -- -- &to jn-lA,, sin (nrx/b) 2rD

1[
E E irD

anA,,, 'cos ((m n)0 -- nuk)

2 1

m n

cos ((m n)0 -- m4)1

where

1

an'

-- 2

ao2 (1 -I- F)Rdo,

(27)

Rd, = ira -- Ro. D

Considering the fundamental only,

W. = a02(1 ao2 (1

4 al

--ir

--
ao

1 ai2
--
2 ao2

(1 ± F)Rd.

4 ai

--

(1 ± F)Rdo.

r do

(28)

It is clear from (28) that W. is increased by the ratio

(1 + 4 --ai\
ir aoi

due to the non-uniformity of current distribution. Substitution of (18) and (19) gives

4 ai

7r

do

= 2{2,4 0+ --78r2(d11 +

+ 9

···)1

/{ 22rBi D2 a2,,2 62

(2A0+ Ai)} ·

(29)

In --

+non

sin mo) ± (9

]arl2

-7r12

(24)

If the current were uniformly distributed and equal to ao,(23) and (24) would reduce, respectively, to

ao 2 b 2 pr d(aA o)

B, 5 =

° 2

a D 12 da

and

 E

1 d(aA n) cos (nrx/b)}
n da

E 2 in--lAn sin (nrx/b). 2rD n-i

(25) (26)

VII .DETERMINATION OF HF COIL RESISTANCE
The coil losses are mainly copper losses due to skin and proximity effects. The losses due to skin effect have been satisfactorily obtained by various authors. Loss per cm length of astraight circular conductor carrying a current I (rms), given by Butterworth, equal to PR0(1±F), where Ro=dc resistance per cm length, F is a function of t, given in Butterworth's paper, and t2=22r2fd2Wp. Therefore, loss along whole coil due to

If the current were uniformly distributed and the coil were shunted with C., the ratio with which the loss increases would be equal to

1 0,2

2f÷__' 1

1 -- 442 1

2C, = 1± 2

_CO2L1CC.

Substitution of (18) gives
2 1 i} co2L,C,

2rB i D2 = 2(2/1 0 ± Al)/ .1(Ow' 62

(2A 0 + Ai)} . (30)

Now, numerators of (29) and (30) are nearly equal, indicating that the increase in skin loss can be approximately obtained as if the coil were shunted by C., provided co/22r is far from cor/2r.
For the determination of the losses due to proximity effect, two cases will be considered. One case is when the coil turns are not too closely wound. The other case is when the coil turns are closely wound. In the first case, the magnetic field at any point along the coil could be considered uniformly distributed over the cross section. The problem, therefore, reduces to the

544

PROCEEDINGS OF THE I.R.E.

April

determination of the losses in a cylindrical conductor per cm length when cut by auniform magnetic field B perpendicular to its axis and which was given by Butterworth as 25R0.132d2G, where G is afunction of tgiven in Butterworth's paper. Therefore, losses along whole coil due to proximity effect are

J 1
= --

6/2
257raRo(B.t2
--b/2

BRI 2)d 2Gdx.

Substitution of (23) and (24) for .13ze and Bite, respectively, gives the following:

d2

W, = ao2Rd.D--2GI(Ki + K2) + (12 +12)1,

(31)

where
E K1=25 --2 An2=function of b/a (Fig. 9). 3 .2

If the turns of the coil are closely wound, the magnetic field components at any conductor cross section of the coil can no longer be considered uniformly diitributed over the cross section. The form of field varia-
tion depends on the position of the cross section along the coil as well as on whether the field component is axial or radial. It should be noted that the form of field variation is mainly due to adjacent turns, and hence it can be approximately considered the same along the coil except at the two end turns. In this way, the problem reduces to the determination of the losses in a solenoid when subjected to a mean-square value of two field components, one radial and the other axial.

K2=25

4 b2

je

,} (Ao)

2

74 el_ 4 lda

+ 21{ Gda( anAn))2}

+2 d(aA 0)z _d

da

da

n2 Li

#.6 · 7
.5

=another function of b/a (Fig. 9).

el/ e
4

4

0·9

2
0.7

0.`

U2

o

o .2

.4

.6

.8

t.

Fig. 10

3

Following Butterworth's work, the modifying factors

for the radial and axial field contributions could be taken

as 0 and -y given in Butterworth's equation; therefore,

o

a2S

0.5

0.75

10

R25

tge

1.76 . 20

/e

Fig. 9

f, and 12 are functions of (an/a 0,b/a) and are given in Appendix D.
Ki+12=contribution of total radial component of magnetic field.
K2+12=contribution of total axial component of magnetic field.
If the current were uniformly distributed, (i.e., a=0),
f1=0=12. For the sake of comparison, the radial and axial field
contributions u, and u2, given by Butterworth in his equation, are also shown in Fig. 9.
The total coil copper loss = W.+ W,,.

W, = ao2Rs. D2-- G1(131Ci+ 71(s) + (fil' +712)1.

(32)

Hence,

{ Rne/Rdo = «1
.

4 --

a,, na 0

1

an2

--2 ,_, -- ao} 2 (1

d2 + {(OKI + -y1(2) + (012 + 712)1 T)2-G

F) (33)

eand -y are functions of d/D and 1, and are given in
Fig. 10, which is extracted from Butterworth's paper. If the current were uniformly distributed, a,, =0=f,
=f2, and the resistance ratio would be given by,

R,,,,/Rd,, = (1+ F)

(OKI+ -yK2) D--G2 .

(33a)

It should be noted that although the increase in skin and proximity losses due to the nonuniformity of cur-

1953

Mostafa and Gohar: Characteristics of Single-Layer Coils

545

rent distribution is approximately equal to the increase
in loss if the current were uniformly distributed and the coil shunted by C,,, this is not so if co/22- is near co./27r, even if the harmonics a3,as,···,were neglected. This can be clarified by the following example:
Consider a coil having b/a=1.0, a= 9.7, d=0.0508, and d/D= 0.67. Therefore, C. =2.97 mg, La=1040 ph, cor/2r =2.86 mc/s. If a3=0=a5= ···,and approximations up to A g are only considered, then, at a frequency equal to 0.5 w./27r, al/a0=0.465, fi =2.91, f2 =2.587. Substitution in (33) gives Rao/Rd. = 10.0. If the current were uniformly distributed and the coil shunted with C., the resistance ratio, obtained from (33a) and multiplied by
2::12)1:

(Fig. 11). Curves calculated from (18) and from Palermo's formula are also depicted. Fig. 12 shows C./a against b/a, extracted experimentally from Medhurst's paper as well as the theoretical curve calculated frcm (18). Satisfactory agreement is indicated for coil lengths ranging from 0.2a to a. As Medhurst's experiments were carried out on coils earthed at one end, the conception in Appendix C was adopted.

egA

o
0' 04

Col 4rto TA6

would equal 8.9. Therefore, the effect of nonuniformity of current distribution is to increase the resistance ratio by about 11 per cent over the case if the current were uniformly distributed and the coil shunted with C.. However, at a frequency equal to 0.3 co./27r, the percentage increase is only about 4 per cent. Therefore, the experimental determination of the HF resistance by the reactance variation method at frequencies near the natural frequency of the coil requires modification.
6/4 31 C
Y 2
1 g
24

02

0.2.

0.4

06

.8

1.0

tl

¡ 4

0.
Fig. 12

B. Verification for the Resistance Ratio
The coiling effect X, which is the ratio of the ac coil resistance to the resistance at the same frequency of the same length of straight wire
R.
{= R.(1 F)}
was calculated with equation (33a) for several ratios of b/a and for values of d/D ranging from 0.6 to 0.9. Tables 2, 3, and 4give experimental as well as theoretical values of X; the experimental results in Tables 3and

2 a

TABLE 3

b/a=1.0

t=10

I g

V ee

d/D ·

0.6

0.7

0.8

0.9

, tb

X (experimental)

1.94

2.47

3.17

4.10

ê g

t.....e.>..

X (Authors')

1.80

2.18

3.07

4.76

Autherl Curve

X (Butterworth'

2.06

2.61

3.61

5.57

ripe» intental

01

02

0.5

04

0$

01

o.

Oig

Fig. 11

VIII .EXPERIMENTAL VERIFICATION (EXTRACTED FROM PREVIOUS AUTHORS)
A. Self-Capacitance Verification
Self-capacitance is practically independent of the number of turns and the spacing ratio, contradicting Palermo's theory. An experimental curve extracted from Medhurst's paper for b/a=1.0, d/D ranging from 0.15 to 0.95 and a ranging from 2.6 to 6.4 cm, is given

d/D X (experimental) X (Authors') X (Butterworth)

TABLE 4 Va=0.4,1=8.0

0.6 1.83 1.79 1.95

0.7 2.28 2.257 2.62

0.8 2.97 3.31 3.88

0.99 3.99 5.24 6.02

4are extracted from Medhurst's paper,' while those in Table 2 are taken from a paper by Palermo and Grover." For the sake of comparison, the theoretical values obtained by using Butterworth's equation are also given in the tables.
'3A. J. Palermo and F. W. Grover, "Study of the high frequency resistance of single layer coils," PRoc. I.R.E., vol. 18, p. 2041; 1930.

546

PROCEEDINGS OF THE I.R.E.

April

IX .APPENDICES
A.Effects of Charging Currents other than Those between the Different Turns and the Datum of Zero Potential
As each turn of the coil is at adifferent mean potential from every other turn, there will be capacitances between each pair of adjacent as well as nonadjacent turns (Fig. 13). The capacitances between adjacent

sin DdD = (sin -n-à-r- ) )2/--D

2

2

which is practically the same provided the number of turns is not very small (nD/2=r/2). Therefore, for large number of turns, the integral in (4) and the like could be considered practically unaffected by varying the ratio Dia provided N is large.
The effect of using a value for dia other than 0.01 can also be practically neglected, and can be clarified as follows: In determining Ao,A. in the text, the 48 ordinate scheme was adopted. Let A0,A. be the coefficients at the given ratio of d/a, and A0,,A., be the
corresponding values at another ratio (dia) i.Then,

X Fig. 13

turns are only important due to their screening effect. Let Ai= variation of current, at adistance x, between
two successive turns. If the capacitances between adjacent turns are only considered,

Ai = i -

jwC {(Av) - (6,v21 = jcuCD2d2v/dx2 (34)

where C=capacitance between two adjacent turns =ra/3.6 cosh-1 Did µµf; the adjacent turns considered as if they were two parallel cylinders.
However, if C. is only considered,

= jcoq = jwCV.

(35)

Although C. is generally small compared with C, yis large compared with Av. On the average, Coe could be
considered of the same order as C-,Ckv. Therefore, Ai obtained from (34) could be considered as asmall cor-
recting term for fi given by (35). Accordingly, the change of current between successive turns is, to agood degree of approximation, due to the capacitances C.

B. Effect of Using Ratios for Dia and dia other than 0.005 and 0.01, Respectively

The effect of using avalue for Dia other than 0.005

will be first considered. The pitch to diameter ratio in

almost any practical coil is not less than 0.005, which

is the value considered in the text. If the summation

process is carried out turn-by-turn, the result will not

therefore be affected by any other value for Dia. However, if an integration process is adopted, the result

will be slightly affected. As the representation of Fig.

3 is a Fourier one, the summation can be easily car-

sin ( ried out. As an example,

E sin ,nD =

-n---1D)· sin -n-D-

2

2

sin D/2

while

and

A01 = A o -I- (1/a)i - (lia) 48

A,,,, -

± (1/4 1 - (lia) 24

where (1/a) and (1/a)1 are the values at the ratios (dia) and (dia) i,respectively. The discrepancy is in
general very small. For d/a--0.01, 1/a= 2.95 X10-2 ¿ah/cm, Ao=0.751 X10-2 , Ai= 0.643 X10-2 ph/cm. For a value of dia, so that 1/a is increased by 50 per cent, the coefficients A0 and A1 will be given by 0.75 X10-2 and 0.70 X10-2 ph/cm, respectively. In any
case, the correction can be easily included as illustrated.

C. Coil Earthed at One End
When acoil is earthed at one end, the charge distribution and hence the self-capacitance depend on the position of the coil (its inclination and distance) with respect to an equivalent conducting plane at earth potential.
To simplify the matter, consider the case where a conducting plane is at the earthed end of the coil (Fig. 14). Such consideration, although different from earth-

,,, .· r_l 1%,·

1,/

v

t ·
Iw

g i

L

Fig. 14
ing the end of the coil, should give qualitative and even quantitative approximations. The charge distribution on coil and the induced charges at the conducting plane must be such that potential of the latter is zero. By applying the method of images, the coil and its image (shown dotted) will be treated as in the case where neither end is earthed. The self-capacitance of the coil will therefore be twice the self-capacitance of acoil with neither end earthed and of same diameter but of double length.

1953

Mostafa and Gohar: Characteristics of Single-Layer Coils

D. fi and h Functions

25
=7r 2

( 2 6 as

a -0 --4 Al2 + A2

+ --5 --ai

10 as --25 --a1

\ / 8 ···) --37r Al

8
--3r

8
- 12- 7r A5

· · · )

2 6 as 10 as

32

32

32

)2 -- 15+ --7 al --9 -- al± ···)(-- --15r A1 + --154r43+ --9rA5 -- ···) -I- ···}

a12 {r2

2 6 as

a02 --8A l2 +2A 22(-3-1-5- ai

10 ab 21 -a-lI- ···

971.2

a3 2

· --8 A32 al`

2 82442(-- --15

6 as -- -- 7 al

10 as

25v2

a52

-- 9

-- -- al

···) -F--

8

A5 2a-- 1-+

· · ·

8

2 6 as

+-- AiA2(-- + --

3 5 al

10 as

32

( 2 6 as 10 a5

--+ ···)-- -- AiA4 -- --+ --+------

21 al

15

15

7 al 9 al

24

as( 2

+--5A2A8a--l 3

6 as 10 as

40

ab( 2

5 - ai-- 21 -- ai ± ···) -- 21 A2A6 --ai 3

6 as 5 al

10 ab 21 -- ai+ ···)

96  7

as( 2 ai -- 15

6 as 10 ab

160

ab( 2 6 as

--7 -- al+--9 --ai -- ···) -- --9A4445.a--i -- -15 -F --7 ai

10 as --9 --al -- ·

25 b2[

[ d

1 a3

= -- -- 4 -- -- (ailo)(1 -- -- --

r4 a2

a0 da

3 al

1 ab

d

4 d

4 d

-- -- ± ···) {r -- (ail s) -- -- (aA i) -- -- (ail s)

5 al

da

ir da

9r da

4 d

.r d

d

1 as d

1 as d

+ --257 -(1-4;(aA5) + ···I ± -2-- ia (aAo) {7( (aA1) - -3-- 71-ici-(aA a) ± i 7: it(afts) - ···}

1 il A

2

d

1 3 a3 5 as

I i)} + -(-i-a (aA 2) ( -3 ± --5 --a1 -- --

\I4 d

4 d

+ --2 -Ida (a

21 --a1 4- ··· 1-3r --da (aA1) -- --5r --da (aA5)

8 d

d

1 3 a3 5 as

4 d

_ 105r --da (aA5) - ···} ± --da (ails) (- --15 + --7 --al - --21 --al + ···)·{- --15r --da (aA1)

4 d - --7r --da

4 d

--9r --da (aA5)

- ···}

± · · ·



2( -2-[ {2 --d (M o)} 2(1
do 2

- --3a a 13+a-55 ai-+

\2 .
· · )

v2 (d ,aA ,) 2
--8 lia

2 {d

2



-- (aA2){(1

9 da

9a 3 -- 5a i

15 ab 21 5at

·) 2+

td

2

1---2 2(--

(aA 3)}

8 ai2 da

+ --2225{1 (aA4)} 2(-

45 as 75 1+ -- -- + --
7 ai '9

--as al

···) 2+

--r2

--a52

{d --

(aA s)}

2 ±

8 ai da

· · ·

d

as

as

d

a3 d

as d

-I-·4

-- da

(aA0)

(1

--- ±--
3a1 5a,

-

···){-- ·(aili)
da

-

-- 3a 1

--(aA da

2) ±

-- 5a l

-- da

(ciA5)

-

·

4 d

d

-- -- (aA i)-- (aA 2)(1

9 da

da

4 d

d

(

 -- -- (aA2)-- (a4.18) 1

5 da

da

8 as 15 as -- -- - -- -- ± ···) 5 al 21 al

4 d

d

45 as 75 ab

-- 225

--da

(aA 1)-- (aA4) da

(1

- --7

--al - --9

al

9 as -- 5 al

5 as -- 1-· ·
7 al

) as ai

20 d

d

(

9 as 5 as

-- -- -- (aA 2)--(aA b) 1+ -- -- -- --

63 da

da

5 al 7 al

\ as ai

4 d - 35 da

d

( 45 a3 75 as

da

7 ai

9 al

) as al

4 d -- 27 --da

d

45 as 25 as

-- (aAs)( 1-- da

-- 7

-- ai

--

-- 3

-- 01

+

) ab ·· --

547
11

548

PROCEEDINGS OF THE I.R.E.

Correspondence

April

"Instantaneous" Frequency*

In apaper published recently,' the term

"Instantaneous Frequency" is mentioned

repeatedly. Many authors have already re-

ferred to this term as being fallacious and

misleading, especially in the discussion of

frequency modulation.'.' It is intended, in

the following discussion, to show why this

term is inapplicable, with the hope of ban-

ishing it forever from the dictionary of the

communication engineer.

·

A simple sinusoidal waveform is expres-

sible as, A sin (wt-1-0), or as the real part of

A exp (jwe); in both cases, the constant co is

the angular frequency of the waveform. The

usual accepted extention of this treatment is

to regard anonperiodic function as A sin tt,

or the real part of A exp (j.), where is a

real function of the time t, and to define an

"instantaneous angular frequency" as dedt.

Thus, Manque' treats a function e(t) --exp

[j(coote-FEB2)[, and says, "then the instantane-

ous angular frequency is 0= (coo-F2e0)."

When areal function is expressed as the

real part of A exp (je), with both A and *as

functions of t, the choice of A and cl) is not

unique. The imaginary part of the function

is arbitrary, although some choices lead to

simpler expressions for A and e. If then the

rate of change of ck is regarded as the "in-

stantaneous angular frequency," this is not a

unique function of t. A simple amplitude-

modulated wave, usually expressed by

Re [A(1) exp (jcot)] with a constant w, may

also be expressed as Re [A exp IMO 1],

where A is aconstant whose absolute mag-

nitude is at least as high as the highest am-

plitude of the wave, and 4,(t) is a(nonlinear)

function of t. Therefore, it is possible to re-

gard the wave as having constant amplitude

and acomplicated "instantaneous frequency"

function; this representation is as legitimate

as the usual one, of constant frequency and

variable amplitude.

It appears that the only mathematically

precise, in contrast to "intuitive," approach

to such a term is by a limit process of the

same type that is used to define the slope or

the curvature of acurve at any point. This

process is outlined as follows.

A sine curve A sin (cot-I-4,) may be fitted

to any three points on a given curve f(1).

Three points are necessary, although some-

times insufficient or incompatible, to define

the three independent constants A, co and 43.

f(t) is supposed to be single valued, continu-

ous, and twice differentiable.

Let us find the sine curve that passes

through the points of f(t) whose abscissas are

tand 1-Fàt.

*Original manuscript received by the Institute. October 6, 1952.
1J. Manque, *The response of RLC resonant circuits to EMF of sawtooth varying frequency," PROC. I.R.E., vol. 40. p. 945; August. 1952.
N. L. Harvey. M. Leifer. and N. Marchand *The component theory of calculating radio frequency spectra, with special reference to frequency modulation." PROC. I.R.E., vol. 39, p. 648; June. 1951.
1IV C. Vaughan. *Spectrum of a frequency modulated wave." Wireless Engineer. vol. 29. 13. 217; August. 1952.

f(t) = A sin (col 4,), f(t ± à1) = A sin (cot -I- ± wAt)
= A sin (cot + 0) cos coed ± A cos (cot + 0) sin wed
=f(I) cos coat
± VA' -- V(1) 12 sm coAt.
We will use the following short notations:

f(+) fit + AO f(--) f(1 --AO,
then

f(4-) fcos coà1 + V A 2 -- p sin coW . (1)

f(--) =fcos iota --

2 -- p sin coAt

Solving (I) for the functions of cad,

sin wed

=

f(+) --f(--) 2NIA2 --p

(2)

cos wed = f(+)--f(--)

2f

By division,

tan coAt f(+) +.1 (--) x VA' --P · (3)
The second factor may be found by squaring (2) and adding, giving after some algebraic manipulations,
fi A:
[2.14A+) +A -- )][2f--f(+) -- f( -- )1 (4)

After (4) is substituted in (3), the result is tan coà,
V [2.f+f(+) -Ff( -- il[2.1*-1(+) --e -- ).1 (5)

This is atranscendental equation that gives the "average" angular frequency of the function») for t--At <t < t+AL We now pass to the limit ,11--.0.
tan cuAl wAS i...
f(±)-1±Att +4(ea) 2.1-- + ···
where primes denote differentiation with respect to t. Equation (5) then reduces to

cote

=

V(41)

X

(-- 2f

[A1.1 2.l")

I/ 1,,

0,-- -- --·

(6)

The co in (6) is afunction of 1, and may be
used as an "instantaneous angular frequency." This frequency is real only for points where the curvature of the graph of f(t) is directed towards the t-axis; at points on the t-axis itself the frequency is undefined, unless the curve has an inflection at that point. The expression (6) is evidently

true for the simple case where f=A sin (cot +0).
Suppose now that 1(t) =sin g(t), then

f' = g' cos g
f" = g" cos g-- (g9 2sin g.

= V(g') 2 -- g" cot g.

(7)

The last value is quite different from the

"intuitive" co =g'. (Both values would be the

same only if g"=0, but then g is a linear

function of t, and co is constant.)

The frequency defined by (7) may have

some value in discussing nonperiodic waves;

but the "intuitive" value, nevertheless, is

wrong. Thus, it is easy to understand the

apparent paradoxes in statements like the

following:

"The maximum of the response of atuned

RLC circuit to a voltage of varying fre-

quency does not occur when the instantane-

ous frequency coincides with the resonant

frequency of the tuned circuit"; or, "The

spectrum of afrequency-modulated wave is

much wider than the range of variation of

the instantaneous frequency."

These are erroneous statements, based on

an "intuitive"--but erroneous--interpreta-

tion of aterm.

JACOB SHEKEL

8Ben Yehuda St.

Haifa, Israel

More on Direction Finders*
Hansel's letter on polarization errors in direction finders' raises some interesting points of nomenclature which merit careful consideration. The work of Ross' in relation to Adcock-type direction finders is also relevant.
Let us suppose that a direction finder, designed to give correct indications with vertically polarized waves, is set up on a uniform, unobstructed site. If the incoming radiation has ahorizontally polarized component, an error will in general be observed and, because of this, it is natural and convenient to refer to this component as "unwanted." The more weakly the instrument responds to this component, that is, the smaller the pick-up factor for horizontally polarized waves relative to that for the vertically polarized component, the smaller the error. It is therefore rather confusing that the term "unwanted" should also be applied, as Hansel proposes, to acomponent which, although producing no actual error on aclear site, excites only a weak or zero response.
Iagree, however, that it would perhaps be an unfortunate residual characteristic of a hypothetical instrument if the pick-up

* Received by the Institute, March 27, 1952. 1 P. G. Hansel, *Polarization errors of radio direction finders; a proposed classification," PROC.I.R.E.. vol. 39. p. 970; 1951. 1 W. Ross. "The specification and measurement of polarization errors in Adcock-type direction finders." Prot. IEE (London), vol. 96, pt. Ill. p. 269; 1949.

1953

Correspondence

549

Correspondence

factor for one polarization component were much larger than the other, both components being assumed to give correct bearings on an unobstructed site; for, in certain cases of operation on an imperfect site, large errors might thereby result. Nevertheless, in my opinion, confusion can best be avoided by applying the term "unwanted" to the component which introduces errors when the direction finder is operated on a uniform unobstructed site rather than by allowing it to embrace the wider connotation suggested by Hansel.
Since the additional errors which arise when the instrument is set up in imperfect surroundings are special to each site, it is preferable, as Hansel proposes, to regard these as polarization-sensitive or polarization-dependent site errors.
The distinction between the primary and secondary classes of instrumental polarization errors, put forward by Hansel, is not clearly drawn. It is difficult to see how errors resulting from re-radiation from essential conductors of the direction finder differ from errors of the first class, since both are due to the response of the system as awhole to the unwanted component of the field. When, therefore, polarization errors are measured under controlled conditions on a uniform unobstructed site, Isuggest that they should be considered as instrumental characteristics without attempting further subdivision as part of ageneral nomenclature. It must be borne in mind that even these instrumental errors will, in general, depend upon the height of the system above ground and on the ground constants.
The work described above was carried out as part of the program of the Radio Research Board, and this note is published by permission of the Department of Scientific and Industrial Research.
H. G.HOPKINS D.S.I.R., Radio Research Station
Ditton Park Slough, Bucks
England

km 1/

+ a

An
Ph

February

k-1.451

UV ····

dn is the index of refraction change calculated from the '945 Weather Bureau Ratner Report
data corresponding to A hfrom the surface to aheight of one kilometer above the surface

Fig. 1--Effective earth's radius factor, k. for February.

The Geographical and Height Distribution of the Gradient of Refracfive Index*
SUMMARY
Charts are presented of the February and August distribution of the effective earth's radius factor over the United States. Also included is achart showing the distribution of refractive-index gradient for warm, temperate, and cold climates.
Since the presentation of the theory of internal partial reflections by Feinstein; there has been increased interest in the normal geographical and height distribution of the refractive-index gradient. In view of this in-
*Original manuscript received by the Institute, May 13, 1952.
J. Feinstein, Jour. Appl. Phys.. vol. 22, p. 1952; 1951.

An is the index of refraction change calculated from the /945 Weather Bureau Ratner Report
data corresponding to dh from the sur face to 1 oheight ofone kilometer above the surface

Fig. 2--Effective earth's radius factor, le, for August.

terest, the following preliminary charts are presented.
Some work has been don& to show the geographical distribution over the United States of effective earth's radius but none over a uniform height increment above the earth's surface. Figs. 1and 2are charts of the effective earth's radius factor, k, for the
IR. J. Wagner, Jr., RCA Engineering Report P-43-116; 1951.

months of February and August, respectively. The height interval of these charts is from the surface to 1km above the surface.
Chart 3is an illustration of the climatic variation of the gradient of refractive index to the height of 90,000 feet above sea level. San Juan in July is chosen as an example of a warm, humid climate, Washington, D. C. in October as a temperate or median climate, and Fairbanks, Alaska, in February as

550

PROCEEDINGS OF THE I.R.E.

April

Correspondence

adry, cold climate. The basis for extending the curves above the tropopause is the assumption of an isothermal stratosphere' of --65.3°C as used by Schulkin.4
All data are from the 1945 Weather Bureau Report, "Upper Air Average Values of Temperature, Pressure and Relative Humidity over the United States and Alaska," by Beajamin Ratner. These observations were taken between 2200 and 0100, 75th meri-
dian time. The values of effective earth's radius,
factor, given on Figs. 1and 2are obtained
from the relationship:

k 1.[1

a -- n

-AAn-h]

,

where

a=earth's radius

=6,370 km

n= mean radio refractive index

of the interval

An/Ah =gradient of refractive index

of the interval.

BRADFORD R. BEAN

Central Radio Propagation Laboratory

National Bureau of Standards

Boulder, Colo.

F. L. Whipple. Bull. Amer. Mel. Soc., vol. 33, p.
13; 1952. ·M. Schulkin. Average Radio Refraction in the
lower atmosphere, Proc. IRE. 40, pp. 544-561.

100 e10 -9 70 50
30

O Median climate (Washington -October) o Warm humid climate (Son Juan -July) x Cold dry climate (Fairbanks -February)

Tropopause

7 Son Juan

3

2

dn per meter is the index of refraction gradient calculated

from the 1945 Weather Bureau

Ratner Report

1x10 -9 O

10

20

30

40

Fairbanks

50

60

Washington

70

80

HEIGHT /N THOUSANDS OF FEET ABOVE SEA LEVEL
Fig. 3--Average refractive index, gradient.

Contributors to Proceedings of the I.R.E.

Raymond S. Berkowitz (S'47-A'48) was
born in Philadelphia, Pa. on February 21, 1923. He received the B.S. degree in electri-
cal engineering from the University of
Pennsylvania in October, 1943. Upon graduation he joined the Television Termi-
nal Equipment section of the Radio Corporation of America
in Camden, N. J. From 1944 until 1946 he was an electronic R. S. BERKOWITZ technician in the U. S. Navy. Dr. Berkowitz attended the Moore School of Electrical Engineering, University
of Pennsylvania, receiving the M.S. degree in February, 1948. From July, 1947 until the present he has been on the research and teaching staffs of the Moore School, where he has been concerned with the theory of fire-control equipment and also the interference effect of various types of noise on communication systems. He received the Ph.D. degree in June, 1951.
Dr. Berkowitz is amember of Sigma Xi and an associate member of AIEE. He is

also helping to organize the Society for Industrial and Applied Mathematics.

Dr. Bromberg is amember of Sigma X and the Institute of Aeronautical Sciences

B. G. Bromberg was born in New York,

N. Y. on February 14, 1915. He obtained a

B.S. degree in mechanical engineering in 1936 and a M.S. degree in 1937, both

from New York Uni-

versity. He entered

the aircraft industry

in 1937 and became

chief technical engineer for Consoli-

dated-VulteeAircraft

Corporation in 1943.

After World War

B. G. BROMBERG

11 Dr. Bromberg was employed as a re-

search associate at

Massachusetts Institute of Technology, and

received his Sc.D. degree there in 1947. Since

1947 he has been employed at McDonnell

Aircraft Corporation, Missile Engineering Division. He started as head of the guidance

and control department and is now chief

engineer.

Theodore S. George (A'47-SM'51) was

born on October 10, 1911 in Grove City, Pa.

He received the B.S. degree in mathematics from Grove City Col-

lege in 1932, and the

M.A. and Ph.D. de-

grees in mathematics

from Duke Univer-

sity in 1936 and 1942,

respectively.

From 1938 to 1945

Dr. George served as

instructor and assist-

ant professor of math-

ematics at the Uni-

T.S.GEORGE

versity of Florida. From 1942 to 1945 he

was on military leave as aNaval electronics

officer, leaving the Navy with the rank of

lieutenant commander. During this time, he

served at sea as radar officer aboard acar-

rier and later in the Bureau of Aeronautics

where he was in charge of development of

electronic bombing and fire-control devices.

At the end of World War II Dr. George

1953

PROCEEDINGS OF THE I.R.E.

551

Contributors to Proceedings of the I.R.E.

became aconsulting engineer in the research division of the Philco Corporation, doing theoretical work in a variety of electronic
problems until 1952. He is now at Patrick Air Force Base, Cocoa, Fla.

M. Kamal Gohar was born in Cairo,

Egypt on February 1, 1923. He received the

B.Sc. degree in June, 1944 and the M.Sc. de-

gree in January,

1948, both in electri-

cal engineering from

Fouad I University,

in Egypt. In July,

1949 he was the re-

cipient of the Ph.D.

degree from Alex-

andria University.

Dr. Gohar has

held the posts of a

M. K. GOHAR

demonstrator and lecturer at Fouad

University. He is

now asenior lecturer and, at the same time,

assists in the research activities of Fouad I

University's electrical department. He has

recently been selected by the Technical

Committee of the Egyptian Ministry to act

as a consultant for their Electric Power

activities.

Dr. Gohar is a member of the Institute

of Electrical Engineers, (London).

Raymond D. Hill, Jr. was born in St.

Louis, Mo. in 1921. He received the B.S.

degree in electrical engineering from Wash-

ington University in

St. Louis in 1943.

Mr. Hill has been

closely associated

with the aviation and

electronics industries

since 1940. He has

held a private flying

license since 1941.

From 1944 to 1946,

he served in the U. S.

R. D. HILL

Naval Reserve as an electronic specialist

officer.

After returning to civilian life in 1946,

Mr. Hill joined the engineering staff of the

McDonnell Aircraft Corporation, where he

is now serving as chief of electronics in the

Missile Engineering Division. He has since

been continuously involved in the design and

development of guidance and control sys-

tems for Navy and Air Force guided missiles

and of other aircraft electronic systems. He

is now completing work on the M.S. degree

in electrical engineering at Washington Uni-

versity.

AM El-Samie Mostafa (SM'51) was
born in Cairo, Egypt on April 27, 1917. He received the B.Sc. degree in June, 1937 and
the Ph.D. degree in 1946, both in electri-
cal engineering from Fouad I University,
in Egypt. Dr. Mostafa has
held the posts of teaching assistant
and lecturer at Fouad University, and was
promoted to assistant
professor in 1948. He is now professor of radio engineering,
associated with the research section in radio and tele-communication work at Alexandria
University.
Dr. Mostafa was elected an associate member of the IEE (London) in June, 1948, and was awarded the Fouad El-Awal prize for science in Egypt for 1950.

Herbert J. Reich (A'26--M'41--SM'43--

F'49) was born on Staten Island, N. Y., on

October 25, 1900. He received the M.E. de-

gree from Cornell

University in 1924,

and the Ph.D. degree

in physics in 1928.

In 1929 he joined the

department of elec-

trical engineering at

the University of

Illinois, where he be-

came assistant pro-

fessor, associate pro-

HERBERT J. REICH

fessor, and professor, successively, of elec-

trical engineering. In

January, 1944, he was granted leave of ab-

sence to join the staff of the Radio Research

Laboratory at Harvard University. In

January, 1946, Professor Reich was ap-

pointed professor of electrical engineering at

Yale University, where he is at present.

Dr. Reich has specialized in the fields of

electron tubes and electron-tube circuits,

having published numerous papers on these

and related subjects in various technical

journals. He is the author of "Theory and

Applications of Electron Tubes," and "Prin-

ciples of Electron Tubes," as well as co-

author of "Ultra-High-Frequency Tech-

niques," and "Microwave Theory and Tech-

niques" which is soon to be published. Dr.

Reich is also editor of the Van Nostrand

Series in Communications Engineering.

Dr. Reich has served on numerous IRE

committees, and is amember of the Amer-

ican Institute of Electrical Engineers, the

American Association for the Advancement

of Science, the American Society for En-

gineering Education, and is aFellow of the

American Physical Society.

Kurt Schlesinger (A'41--SM'51) was born

in Berlin, Germany in 1906. After receiving

the Ph.D. degree in engineering in Berlin in

1929, he joined the

Radio Research Lab-

oratory of von Ar-

denne, where he was

engaged in develop-

ment of oscilloscope

tubes and circuits.

From 1931 until

1938, Dr. Schlesinger

was chief engineer in

the television research

K. SCFILESINGER

department of Loewe Radio Berlin. During

that period a com-

plete television system was developed. From

1938 through 1940, he worked in Paris as a

consultant to Radio Gramont, and built

equipment for infra-red telephony for the

French army.

In the United States, Dr. Schlesinger

was with RCA Laboratories at Purdue Uni-

versity, from 1941 through 1944. During

that time he developed a system for tele-

vision sound multiplexing, which employed

frequency modulated wave bursts during the

picture retrace.

From 1944 until 1947, Dr. Schlesinger

was consulting engineer in the Color Tele-

vision Department of CBS. He has since

been executive engineer in charge of televi-

sion research with Motorola Inc., Chicago.

During Dr. Schlesinger's twenty years of

activity in television research he has re-

ceived more than two hundred U. S.

patents, and has authored numerous tech-

nical articles and publications. He has, also,

served on the NTSC committees, working

on television problems.

·

Harry Urkowitz (S'48--A'49) was born on

October 1, 1921 in Philadelphia, Pa. and

educated in the public schools there. He was graduated from the

Drexel Institute of

Technology, Phila-

delphia, Pa. in 1948

with the B.S. degree

in electrical engineer-

ing.

After graduation

Mr. Urkowitz was

employed by the

Philco Corporation in

H. URKOWITZ

their Philadelphia research division, where

he has been to the

present. He is now an acting project engi-

neer with Philco. During World War II he

served in the Army Air Forces from 1942 to

1945 as aradar bombardier-navigator.

Mr. Urkowitz is amember of Phi Kappa

Phi, Tau Beta Pi, and Eta Kappa Nu.

PROCEEDINGS OF THE I.R.E.

April

Institute News and Radio Notes

Calendar of
COMING EVENTS
IRE New England Radio Engineering Meeting, Storrs, Conn., April 11
9th Joint Conference of RTMA of United States and Canada, Ambassador Hotel, Los Angeles, Calif., April 16-17
IRE Seventh Annual Spring Technical Conference, Cincinnati, Ohio, April 18
Symposium on Nonlinear Circuit Analysis, Engineering Societies Building, New York, N. Y., April 23-24
SMPTE Convention, Statler Hotel, Los Angeles, Calif., April 26-30
URSI-IRE Meeting, National Bureau of Standards, Washington, D. C., April 27-30
NARTB Convention, Biltmore Hotel, Los Angeles, Calif., April 28May 1
Electronic Components Symposium, Shakespeare Club, Pasadena, Calif., April 29-May 1
1953 National Conference on Air-
borne Electronics, Dayton, Ohio,
May 11-14
1953 Electronics Parts Show, Conrad Hilton Hotel, Chicago, Ill., May 18-21
High Frequency Communication Symposium, IRE Professional Group on Communications Systems, Long
Lines Auditorium, 32 Avenue of
the Americas, New York, N. Y., June 11-12
Symposium on Microwave Optics, McGill University, Montreal Canada, June 22-24
IRE Western Convention and Electronic Show, Civic Auditorium, San Francisco, Calif.,
August 19-21
International Sight and Sound Exposition and Audio Fair, Palmer House, Chicago, III., September 1-3
National Electronics Conference, Hotel Sherman, Chicago, Ill., Sep-
tember 28-30
1953 IRE-RTMA Radio Fall Meeting, Toronto, Ont., October 26-28
1954 Sixth Southwestern IRE Con-
ference and Electronics Show,
Tulsa, Okla., February 4-6

TECHNICAL COMMITTEE NOTES
Under the Chairmanship of A. G. Jensen, the Standards Committee met on January 8. Chairman Jensen reported on his letter to Charles Dawes concerning ASA C42 subcommittee activities and the scheduling of a sectional committee meeting in the near future. Professor Dawes had reported that the committee was studying the status of its various groups and that the overlapping in definitions work within subcommittees 1, 13, and 14 might be solved by ameeting of the chairmen before the sectional committee meeting. Mr. Jensen commented on the over-all question of frequency-band nomenclature and the progress made by CCIR Study Group XIV on the proposed standardization of frequency-band designations. The proposed Standard on Electron Devices: Methods of Measuring Noise, which was submitted by the Electron Devices Committee, was discussed and minor revisions recommended by the Standards Committee. The standard was approved. There was a recommendation to change the name of Committee 26 from the Committee on Servo-Systems to the Committee on Feedback-Control Systems; the change was approved.
On February 5, the Audio Techniques Committee met under the Chairmanship of C. A. Cady. The Committee completed the proposed revision to ASA C16.5.
The Electron Devices Committee met on January 9, under the Chairmanship of G. D. O'Neill. Chairman O'Neill reported on the klystron definitions now on the Grand Tour. The comments received indicate that no changes are needed; the definitions will be considered by the Standards Committee in the future. M. E. Hines reported on the Ad Hoc Committee on Reorganization of Committee 7. H. L. Owens inquired when the Solid State Definitions report would be available. Chairman O'Neill suggested R. M. Ryder be contacted concerning these definitions. S. F. Kaisel has accepted an invitation to serve on the Committee and his appointment has been
approved by the IRE Executive Committee. On January 14 the Measurements and
Instrumentation Committee met in Wash-
ington, D. C., under the Chairmanship of F. J. Gaffney. W. D. George reported on the activities of Subcommittee 25.1. This
Subcommittee has accumulated definitions on voltage measurements which will be submitted to the Committee. The Subcommittee also is working on a standard for
voltage measurement applicable for signalgenerator output, and it is estimated that it will be available in approximately four months. J. H. Muncy reported for J. G. Reid, Jr., on the activities of Subcommittee 25.14. Harold Dinger reported on the work of the new Subcommittee 25.8 on Interference Measurements whose first meeting was
held on January 29. As apreliminary action the more important and fundamental terms in the field will he defined. H. M. Joseph
attended the Measurements and Instru-

mentation meeting as representative of P. S. Christaldi, and discussed the work of the Subcommittee on Oscillography. A written report on the activities of Subcommittee 25.13 on Telemetering was given.
Under the Chairmanship of P. C. Sandretto the Navigation Aids Committee met on January 16. The Committee completed consideration of the third section of Harry Davis' list of terms.
NEW ENGLAND RADIO ENGINEERING
M EETING
A Radio Engineering Meeting sponsored by the North Atlantic Region of the IRE is to be held April 11 at the University of Connecticut, Storrs, Conn. Morning and afternoon sessions will be held in the Student Union Building.
Guest speaker is to be D. E. Noble, a former professor at the University now vice president and director of research of Motorola, Inc. Dr. Noble was influential in introducing frequency modulation. Six papers are to be given.
LAST CALL FOR W ESTERN IRE
CONVENTION PAPERS
Authors are invited to submit prospective papers for the IRE part of the 1953 Western Electronic Show and Convention to be held in San Francisco, Calif., on August 19-21. The dealine is May 1.
Papers in the fields of antennas and propagation, circuits, communication theory, computers, control and instrumentation, electronic devices, uhf and microwave techniques, nuclear electronics, transistors, and non-vacuum tube electronics are particularly desired, but no paper should be withheld if it does not fall into one of these categories. In general, the time allowed will be 30 minutes per paper.
The following should be submitted to B. M. Oliver, Hewlett-Packard Co., 395 Page Mill Rd., Palo Alto, Calif.: (1) name, address, and affiliation of author, (2) title and 100 word abstract, (3) the paper, or a summary of 500 words.
AUTOMATIC CONTROL COURSES
OFFERED
The University of Michigan, College of Engineering, has announced two intensive courses in automatic control. The classes are scheduled for June 15-20 and June 22-25, 1953, and are intended for engineers who wish to obtain abasic understanding of the field.
The courses are built around the principles and application of measurement, communication, and control, and will include some fundamental work in nonlinear systems. The role of analog computing methods also will be emphasized.
The deadline for registration is April 15, 1953. Further information may be obtained from: Professor M. H. Nichols, Room 1523, East Engineering Building, University of Michigan, Ann Arbor, Mich.

1953

Institute News and Radio Notes

553

Professional Group News

AIRBORNE.ELECTRONICS
The Professional Group on Airborne Electronics sponsored a symposium on "Electronic Control and Stabilization of Aircraft," and a technical session on the "Import of Electronic Trends on Aircraft Design" at the annual meeting of the Institute of Aeronautical Sciences, held January 28, 1953, the Hotel Astor, New York, N. Y. The IRE session was presided over by General P. C. Sandretto of International Telephone and Telegraph Corporation and Federal Telecommunications Laboratories.
General Sandretto made the following remarks in opening the session:
"While the Wright Brothers demonstrated powered flight in 1903, it was several years before the airplane had reached the stage of development where it could be regarded as a means of transportation and had acquired unique navigational problems. By one of those coincidences which have had a profound effect on the course of history, radio development paralleled in time that of the airplane. It was in 1902 that John Stone obtained a patent on the first device applying radio to navigation, and in 1910 when the airplane was in need of navigational equipment, James McCurdy transmitted aradio message from the air. Radio and the aeronautical sciences were therefore united to bring forth air transportation.
"The joining of radio and aeronautics, was, however, aunion of convenience rather than love because two more incompatible equipments than the airplane and the radio set could hardly be found.
"Flight's greatest obstacle is weight and radio equipment is heavy. Radio equipment is delicate and dislikes avibrating ambient. Yet all aircraft have pronounced vibration characteristics. Any protusions reduce the efficiency of an airplane, yet all radio installations operate best with large protruding antennas. And so on, and on, we could mention the incongruity of applying radio to aviation.
"For years the problems of incompatibility were largely ignored. It was not until 1936 that the first aircraft had radio equipment engineered into it at the time of its inception. The radio engineers did little better in approaching the problem from their end.»
Walter Robinson, research supervisor and assistant professor of mechanical engineering at Ohio State University presented a paper on the systematic cooling of airborne electronic equipment. He described seven methods which were applied to cooling a power supply unit having a heat dissipation of 330 watts. Tests were conducted on large tubes with noncylindrical shell.
Another paper, by William Sichak, J. J. Nail, and A. G. Kandoian, of Federal Telecommunications Laboratories, concerned the problem of obtaining satisfactory patterns from uhf antennas mounted on large aircraft. After extensive work to determine the patterns which could be expected from antennas mounted in various places in the aircraft, the authors concluded that multiple antennas must be used. Applying the

multiple antenna system to give suitable pattern for distance measuring or radar beacon purposes was relatively easy, but there were problems to be solved before it could be used for other applications.
H. F. McKenney in his paper, "What Magnetic Amplifiers Can Do to Increase Aircraft Reliability," stressed that the advantages of magnetic amplifiers were (I) no warm-up time, and (2) no cooling problems. After describing design criteria, applications to converters, turret drives, auto pilot, and pulse generator were discussed. He stated that pulses with time durations of the order of three microseconds had been obtained.
Applying electronics to aircraft engine control was discussed in a paper by J. D. Peterson and R. W. Curran. The cumbersomeness of the present cable and pulley system of throttle and mixture controls was compared to one using a servo amplifier consisting of afive pound servo motor and a five pound servo amplifier per engine. Only two tubes are used in the magnetic amplifiers, and in 2,000 hours of operation there had been no failure. A number of provisions were made to take care of the most prominent failures that might occur.
The Dayton Chapter of the group met recently at the Biltmore Hotel, under the chairmanship of Maurice Jacobs. David Weber of the Collins Radio Company spoke about "Modular Airborne Electronic Design," illustrating his remarks with diagrams and a model of a commercial airline transmitter receiver.
AUDIO
The Milwaukee Chapter of the Professional Group on Audio met recently at the Engineers Society of Milwaukee Building. D. E. Mereen presided and N. C. Pickering, Pickering Corporation, spoke on "Pickups and Preamps for High-Quality Audio." Mr. Pickering placed special emphasis on the possibility of overloading the first audio tube by the signal induced from the pickup head.
The Philadelphia Chapter of the group held two meetings recently at the Edison Building Auditorium of the Philadelphia Electric Company. W. E. Kock, director of acoustics research, Bell Telephone Laboratories, gave a paper entitled, "The Physics of Music and Hearing," with demonstrations. He outlined the physical concepts of hearing and reviewed the spectral content of musical instruments. He also discussed electrical means for reproducing and imitating existing orchestral instruments. A motion picture, "Action Pictures of Sound," was also shown. At the second meeting, F. H. Slaymaker, Stromberg-Carlson Company, gave a paper entitled, "Performance Criteria of Loudspeakers."
BROADCAST AND TELEVISION RECEIVERS
Stephen Bushman presided over arecent meeting of the Chicago Chapter of Professional Group on Broadcast and Television Receivers, held in the Western Society of Engineers Auditorium.

L. H. Horn, Underwriter Laboratories, Inc., presented apaper titled "Underwriters Laboratories View Connections of UHF and Color-Adapters to VHF-TV Receivers." Mr. Horn reviewed problems of receiver replaceable-and-attachable devices from the pre-war era to the present. He classified adapters into two categories, those which can be safely installed by the customer, and those much must be installed by servicemen.
S. W. Jacobson, director of research, E. I. Guthman & Company, spoke on "A New Television Horizontal Output Transformer." He showed how early TV receiver horizontal-deflecting systems, using 9-kv high voltage and 53-degree deflection with 390-volt Bt, have been improved through the use of ceramic transformer cores, high perveance tubes, high inductance yokes, and improved drive circuitry. Such systems now give a high efficiency performance of 15hkv and 70-degree deflection with 140-volt Bt and 11I-watts input.
CIRCUIT THEORY
The Chicago Chapter of the Professional Group on Circuit Theory met recently at the Western Society of Engineers Auditorium, L. E. Pepperberg as Chairman. Speaker C. A. Stone of the Armour Research Foundation spoke on electronics in nucleonics.
VEHICULAR COMMUNICATIONS
The Los Angeles Chapter of the Professional Group on Vehicular Communications met in February at the Institute of Air Sciences Building. M. E. Kennedy was the Chairman.
W. A. Miller, Radio Division of the Pacific Telephone and Telegraph Company, presented a paper called, "The Use of Vehicular Communication Equipment in the Telephone Plant." It concerned the development of telephone communication to mobile units in that area. Many technical problems were discussed in adjacent channel operation, intermodulation, and selectivedial calling.
ELECTRONIC COMPUTERS
Over 700 people attended the Western Computer Conference held on February 4-6, Hotel Statler, Los Angeles, Calif., sponsored by the Joint Computer Conference Committee representing the IRE Professional Group on Electronic Computers, the American Institute of Electrical Engineers, and the Association for Computing Machinery.
Reports were given on commercial applications of computers, applications to aircraft and missile design, and new developments in digital and analog computer equipment. There was also apanel discussion on the relative merits and applications of analog and digital computers. Products and services of twenty-two organizations were displayed.
Proceedings of this Western Computer Conference will be available from the IRE and can be ordered for $3.50 from: L. G. Cumming, Institute of Radio Engineers, 1East 79 Street. New York 21, N. Y.

554

PROCEEDINGS OF THE I.R.E.

April

1953 Convention Record of the I.R.E.

Join the IRE Professional Groups to Receive Convention Papers

All available papers presented at the 1953 IRE National Convention will appear in a new publication, the CONVENTION RECORD OF THE I.R.E., to be published in June. The CONVENTION RECORD will be issued in ten Parts, with each Part devoted to one general subject.
Instructions on Ordering
1. If you are a member of an IRE Professional Group and have paid the Group assessment by April 30, 1953, you will automatically receive, free of charge, that Part of the CONVENTION RECORD pertaining to the field of interest of your Group, as indicated in the chart below.
2. If you are not amember of an IRE Professional Group, or if you are a member

but have not paid an assessment, pay the group assessment listed below and re-
ceive, without additional charge, not only the corresponding Part of the CONVENTION RECORD but all publications issued by the Group during the assessment Period. To join aGroup, you must be an
IRE member. 3. In addition, CONVENTION RECORD Parts
may be purchased at the prices listed in the chart below. Orders must be accompanied by remittance, and, to guarantee delivery, must be received by April 30, 1953, at the Institute of Radio Engineers, 1East 79 St., New York 21, N. Y.

Group Assessments
Airborne Electronics

$2.00

Antennas and Propagation

$4.00

Audio

2.00

Broadcast and Television Receivers . 2.00

Broadcast Transmission Systems

2.00

Circuit Theory

2.00

Communications Systems

2.00

Electron Devices

2.00

Electronic Computers Engineering Management

2.00 1.00

Industrial Electronics

2.00

Information Theory

2.00

Instrumentation

1.00

Medical Electronics

1.00

Microwave Theory and Techniques

2.00

Nuclear Science

none

Quality Control

2.00

Radio Telemetry and Remote Control 1.00

Vehicular Communications

2.00

Part
1
2
3 4
s
6
7
8
9
10

CONVENTION RECORD OF THE I.R.E.

Title
Radar and Telemetry Sessions: 6, 12, 37, 43
Antennas & Communications Sessions: 1, 7, 13, 18, 28
Audio Sessions: 25, 31, 38
Broadcasting & Television Sessions: 2, 8, 23, 29, 35, 41
Circuit Theory Sessions: 3, 9, 15, 21
Electron Devices-- Engineering Management
Sessions: 16, 20, 24, 26, 39
Electronic Computers Sessions: 4, 10, 14
Information Theory Sessions: 22, 27, 33, 40
Instrumentation-- Nucleonics-- Medical Electronics
Sessions: 5, 11, 17, 32, 34
Microwaves Sessions: 30, 36, 42
Complete Convention Record (All Ten Parts)

Free to Paid Members of Following IRE Professional Groups
Airborne Electronics Radio Telemetry & Remote Control
Antennas & Propagation Communications Systems Vehicular Communications
Audio

Other IRE Members
$1.00

Nonmembers

Public Libraries and Colleges

$3.00

$2.40

1.25

3.75

3.00

1.00

3.00

2.40

Broadcast Transmission Systems Broadcast & TV Receivers
Circuit Theory

1.50 1.25

4.50 3.75

3.60 3.00

Electron Devices Engineering Management Quality Control Industrial Electronics
Electronic Computers

1.00 1.00

3.00 3.00

2.40 2.40

Information Theory

1.25

3.75

3.00

Instrumentation Nuclear Science Medical Electronics

1.25

3.75

3.00

Microwave Theory & Techniques

1.00

3.00

2.40

.

11.50

34 .50

27.60

1953

Institute News and Radio Notes

555

1953 Electronic Components Symposium

APRIL 29--M AY 1, PASADENA, CAL/F.

An attendance of over 1,500 scientists, engineers, and executives is indicated for the 1953 Electronic Components Symposium, April 29-May 1, Shakespeare Club, Pasadena, Calif.
The three-day meeting, which is sponsored by the IRE Professional Group on Instrumentation, American Institute of Electrical Engineers, Radio Television Manufacturers Association, and West Coast Electronic Manufacturers Association, will feature the theme "Critical Problems Being Faced by the Electronic Industry in Meeting Industrial and Military Demands."
Sessions will be open to the public and registration may be made by writing to: The Symposium Headquarters of the Stanford Research Institute, Los Angeles Division, 621 South Hope, Los Angeles 17, Calif.
The symposium program follows:
Wednesday, 9:45 A.M., April 29 WELCOME
Chairman, A. M. Zarem, 1953 Electronic Components Symposium, Stanford Research Institute, Los Angeles, Calif.
Wednesday, 10:00 A.M., April 29
SESSION 1--GENERAL
Chairman, Simon Ramo, Hughes Aircraft Co., Culver City, Calif.
"The Development of Industry Standards by the RTMA," R. R. Batcher, Radio Television Manufacturers Assn., New York, N. Y.
"Inferences from Tests of Electronic Ordnance," B. P. Ramsay, U. S. Naval Ordnance Lab., Silver Spring, Md.
"A Critical Compilation of Electronic Information," Richard Larson, Vitro Corporation of America, Silver Spring, Md.
"The Component Problem in Industrial Electronics," E. D. Cook, General Electric Co., Schenectady, N. Y.
Wednesday, 12:00, April 29 LUNCHEON
Luncheon Address, Speaker and Subject to be announced
Wednesday, 1:45 P.M., April 29
SESSION 2--ENVIRONMENT AND PACKAGING
Chairman, A. W. Rogers, Signal Corps Electronics Lab., Fort Monmouth, N. J.
"Protective Coatings for Etched Circuit Wiring," Morris Weinberg and L. J. Martin, Hughes Aircraft Co., Culver City, Calif.

"Review of Component Progress for AutoSembled Electronic Equipments," V. J. Kublin and R. A. Gerhold, Squier Signal Lab. and Signal Corps Engineering Lab., Fort Monmouth, N. J.
"Components for Mechanized Production of Electronic Equipment," L. K. Lee and F. M. Hom, Stanford Research Institute, Stanford, Calif.
"Recommended Temperature Measuring Techniques and Ratings for Electronic Parts,» J. P. Walsh, Cornell Aeronatuical Laboratory, Inc., Buffalo, N. Y.
"The Behavior of Component Parts in HighIntensity Short-Duration Environments," C. R. Gates and F. A. Paul, California Institute of Technology, Pasadena, Calif.
"Temperature-Pressure Derating of Electron Tubes," Bernard Smith, Wright Air Development Center, Dayton, Ohio
Wednesday, 6:30 P.M., April 29
DINNER
Dinner Address, Speaker and Subject to be announced
Thursday, 9:30 A.M., April 30
SESSION 3--TUBES AND TUBE RELIABILITY
Chairman, To be announced
"Electron Device Reliability vs. Post-War Equipment Complexity," J. E. Gorham, Evans Signal Lab., Fort Monmouth, N.J.
"Statistical Control of Electron Tube Reliability," A. J. Heitner, Sylvania Electric Products Inc., Emporium, Pa.
"Performance of Vacuum Tubes in Military Applications," E. R. Jervis and R. Madison, Aeronautical Radio, Inc., Washington, D. C.
"Reliability--Tubes vs. Transistors," C. W. Martel, Raytheon Manufacturing Co., Newton, Mass.
"Improving Equipment Reliability by Tube Aging and Inspection,» R. E. Colander, Bendix Aviation Corp., North Hollywood, Calif.
Thursday, 12:00, April 30
LUNCHEON
Luncheon Address, Speaker and Subject to be announced
Thursday, 1:45 P.M., April 30
SESSION 4--RELIABILITY
Chairman, M. B. Carlton, Research and Development Board, Washington, D. C.
"The Case of Reliability vs. Defective Components et al.," R. M. C. Greenidge, Bell Telephone Lab., Murray Hill, N. J.
"The Necessity of Statistical Experimental Design in Testing for Component Re-

liability," J. L. Blair, Consolidated Vultee Aircraft Corp., San Diego, Calif. "Rudiments of Good Circuit Design,» N. H. Taylor, Massachusetts Institute of Technology, Cambridge, Mass. "Reliability of Transistors," R. M. Ryder and W. R. Sittner, Bell Telephone Lab., Murray Hill, N. J.
Thursday, 4:00 P.M., Aprij 30
ROUND TABLE ON RELIABILIte
Participants, The authors of the pàpers in day's sessions, and R. R. Carhart, The Rand Corp., Santa Monica, Calif.; R. Lusser, Los Angeles Ordnance District Office, Pasadena, Calif.
Friday, 9:30 A.M., May 1
SESSION 5--RESISTORS, CAPACITORS AND DIELECTRICS
Chairman, Louis Kahn, Aerovox Corp., New Bedford, Mass.
"Characteristics and Applications of Voltage Sensitive Dielectrics," George S. Shaw and J. L. Jenkins, Radiation, Inc., Melbourne, Fla.
"Some Characteristics and Limitations of Capacitor and Resistor Components," Julian K. Sprague and Leon Podolsky, Sprague Electric Co., North Adams, Mass.
"New Developments in General Purpose Ceramic Dielectric Capacitors," A. K. Das Gupta and W. G. Delp, Solar Manufacturing Corp., Los Angeles, Calif.
"Recent Developments in Dielectric Materials Related to Component Development," G. T. Kohman, Bell Telephone Labs., Murray Hill, N. J.
"Quality Components and Improved Dielectrics," A. J. Warner, Federal Telecommunication Laboratories, Inc., Nutley, N. J.
Friday, 2:00 P.M., May 1
SESSION 6--DEVICES AND MATERIALS
Chairman, Reuben Lee, Westinghouse Electric Corp., Baltimore, Md.
"New Ferritic Materials," Ephraim Gelbard, General Ceramics and Steatite Corp., Keasbey, N. J.
"Ferro-Resonant Devices," Hugo Woerdemann, Magnetic Research, Inc., El Segundo, Calif.
"Transformer Design Limitations,» R. M. Hanson, Transonic, Inc., Bakersfield, Calif.
"Selenium Rectifier Characteristics and Limitations,» G. B. Farnsworth, General Electric Co., West Lynn, Mass.
"Contact Phenomena as Related to Miniaturization," Frank Spayth, P. R. Mallory & Co., Inc., Indianapolis, Ind.

556
IRE People

PROCEEDINGS OF THE I.R.E.

April

James L. Hollis (S'37-A'40-M'44-

SM'46) has joined the E. C. Page Company

Consulting Radio Engineers of Washington, D. C.

Mr. Hollis was

born in Omaha, Neb.,

in 1916, and received

the B.S. degree in

electrical engineering

from Kansas State

College, in 1938. He

spent one year with

First National Tele-

vision, Incorporated,

J. L. Hows

of Kansas City, and in 1939 joined the

broadcast engineering staff of the Crosley Corporation, Cincinnati, Ohio.

In 1947, Mr. Hollis joined the Collins Radio Company, in Cedar Rapids, Iowa, and was a project and group engineer in

charge of high-frequency transmitter de-

velopment for six years. He also was responsible for the development of a line of

high-power air-cooled communications and

international broadcast transmitters.

Mr. Hollis has been active in the Cedar

Rapids IRE Section and their 1952 Con-

ference on Communications. He is a mem-

ber of the National Society of Professional

Engineers and Kappa Eta Kappa.

·:*

Melvin Mailer (M'50) electronics engineer with the National Bureau of Standards, Corona, Calif., died recently. He was 34 years of age.
A native of New York, Mr. Mailer
received the B.S. and M.E.E. degrees from New York University in 1939 and 1948, respectively. He also took advanced work at the Polytechnic Institute of Brooklyn.
In 1941 Mr. Mailer became affiliated with the Signal Corps Engineering Laboratory in Red Bank, N. J. From 1946-1950 he was amember of
the Watson Laboratory in Red Bank, where he became chief of the systems instrumentation unit.
Mr. Mailer transferred to the National Bureau of Standards in
Washington, D. C., and in 1951 he moved to Riverside, Calif., with the NBS missile development division. He was leader on a classified missile development project, and acted as consultant to the engineering section on microwave designs and test equipment specifications. He also was in charge of special transformer design and specifications.
Mr. Mailer was a member of the American Society of Mechanical Engineers.

Joseph M. Conroy (A'23-SM'51) has

been named director of engineering of

Canadian Aviation Electronics, Montreal,

Canada. He will be

responsible for ad-

vising the president

on general engineer-

ing matters, for long-

term planning of prod-

uct development, and

for the solution of

special engineering

problems. He joined

the company in 1951

J. M. CONROY

as chief engineer. Mr. Conroy was

born in Ottawa, Can-

ada, and received the B.S. degree in elec-

trical engineering from McGill University

in Montreal.

For over twenty-five years, Mr. Conroy

has occupied engineering administrative

positions in the electronic industry in

Canada. He has been associated with such

companies as Canadian General Electric,

Canadian Marconi, and RCA Victor.

John Van Nuys Granger (S'42-A'45-

M'46-SN1'51) has been honored by the Eta Kappa Nu Association as its choice of "The

Outstanding Young Electrical Engineer

of 1952."

A native of Marion, Iowa, Dr. Gran-

ger received the B.A.

degree in 1941, from

Cornell College, and

the M.S. degree from

Harvard University

in 1942, where he

J. V. N. GRANGER

worked in the Radio Research Laboratory

on development of homing systems for missiles and airborne vhf direction finders.

During World War II, Dr. Granger

joined the American-British Laboratory at Great Malvern, England, to become group

leader of the antenna group and atechnical

observer with the United States Air Corps.

Later he was atechnical advisor to the First

Tactical Air Force (French-American) in

France, and helped plan and evaluate the radar counter measures program.

After the war, Dr. Granger returned to Harvard University as antenna group

leader of the Electronics Research Labora-

tory, and received his Ph.D. degree there in 1948. In 1949 he joined the Stanford Re-

search Institute, where he is presently as-

sistant chairman of the engineering department and head of its Aircraft Radiation Systems Laboratory.

Dr. Granger is amember of the panel on

antennas and propagation of the Committee

on Electronics--a division of the govern-

ment's Research and Development Board,

and, in 1951, was named chairman of the subpanel on airborne antennas. He is amem-

ber of the International Scientific Radio Union and the Institute of Aeronautical Sciences.

Group Captain E. A. D. Hutton

(M'46), Commanding Officer of

RCAF Station, Clinton, Ontario, died

recently.

Born Feb-

ruary 16,1909,

in Manchester,

England, G/C Hutton was

educated at

the Polytechnic Institute in

London, and

engaged in the

E. A. D. Horror;

operation and maintenance of

commercial radiotelegraph stations before enlisting

in the RCAF as an airman in 1934. Captain Hutton was active in Air

Force signals work and co-operated

with the De Havilland Aircraft Company in developing the first RCAF

radio-trainer aircraft. He was an instructor until assigned to RAF

Bomber Command Headquarters in

England as signals training officer.

For this work he was on the King's Honours List for 1945.

Appointed to the Canadian Joint

Staff in Washington, D. C., Captain

Hutton served as chief signals officer until 1948 when he became director of

telecommunications operations.

He was a member of the British

Institute of Electrical Engineers.

e:r

W. W. MacDonald (A'31-SM'52) has

been appointed editor of Electronics by the

McGraw-Hill Publishing Co., Inc., New

York, N. Y. Mr.

MacDonald became

associate editor of

the publication in

1941, managing edi-

tor in 1944, and

executive editor in

1952.

Mr. MacDonald

was born in Brook-

lyn, N. Y., and

W.W. MACDONALD

studied at Columbia University. After two

years as a field en-

gineer, he joined McGraw-Hill in 1926, and

then spent a year supervising communica-

tions equipment installations in Central and

South America.

Before becoming associated with Elec-

tronics in 1941, Mr. MacDonald was suc-

cessively managing editor of Electrical

Merchandising and editor of Radio Retailing.

1953

Institute News and Radio Notes

557

Harold E. Gumbart (A'45), senior sales engineer for New Products Division of Corning Glass Works, has been appointed Western district sales representative, located in Los Angeles, Calif.
Born in Illinois, Mr. Gumbart received a B.S. degree in electrical engineering from the Carnegie Institute of Technology and did graduate work in business law at Columbia University.
From 1916 to 1928 Mr. Gumbart was in the export department of Standard Oil Company of New York, then with Brown Company of Portland, Me. In 1933 he became assistant to the president of the Fibre Conduit Company, and in 1936 sales manager. Since 1941 he has been with the Corning Glass Works.

Russell A. Berg (A'37-M'45) has been

promoted to the position of chief engineer

at the New London Instrument Company,

New London, Conn.

Mr. Berg was

born in 1914 in New

York. He received

the B.E. degree from

Yale University in

1936 and did gradu-

ate work at the Poly-

technic Institute of

Brooklyn.

In 1936 Mr.

R. A. BERG

Berg was a student engineer with the

Underwood Elliott

Fisher Company, and later transferred to

RCA Communications, Inc. He subse-

quently worked for the Westinghouse Elec-

tric Company as atester and radio operator,

and the Hammerlund Manufacturing Com-

pany as atester and wireman.

During World War II, Mr. Berg was a

radio engineer at the Coles Signal Corps

Laboratory, Red Bank, N. J. Prior to his

present position he was with the Trad Tele-

vision Corporation.

·

William L. Foss (A'49), consulting engineer and a pioneer in radio electronics, died recently at his home in Washington, D. C.
A native of Maine, Mr. Foss studied law in addition to engineering and
received a legal degree from the American University. He started his professional career as a director of engineering and operational work for a chain of New England radio sta-
tions. From 1928-1941, Mr. Foss was a
consulting engineer in Washington, D. C., and from 1941-1945 he worked with Army Signal Corps and Air Force communications. In 1951-1952 he was aliaison between the United States and Canada for a joint radar warning system.
Mr. Foss was amember of Radio
Pioneers and the Society of Motion Picture and Television Engineers.

B. A. Nicholas (A'14-SM'46), an executive of the International Telephone and Telegraph Corporation,
died recently at the age of 59. Long aleader in the manufacture
of television, radio, and phonograph
equipment, Mr. Nicholas directed the patent contract department of IT&T. He was president of the Farnsworth Radio and Television Corporation from 1938 to 1949, when it merged with IT&T, and transferred to that organization.
A native of Ohio, Mr. Nicholas attended the Cleveland School of Commerce and New York University. He began his career with the United Wireless Company in Cleveland. Subsequently, he became a wireless op-
erator, manager of the Marconi Company wireless station in Cleveland, and chief operator and inspector of the Great Lakes Division.
Mr. Nicholas served as assistant to the vice president and general manager of the Radio Corporation of America in Indiana, and sales manager of the Eastern division; manager, then vice president, of RCA Radiola division. Next he assumed the presi-
dency of E. A. Nicholas, Inc., became vice president in charge of sales for RCA Victor, manager of its licensing division, and a member of the advisory board.
Mr. Nicholas was adirector of the Radio and Television Manufacturers Association, and alife member of the Veteran Wireless Operators Association, which in 1944 presented him its Marconi Memorial Commemorative Medal of Achievement.

4C·

Benedict V. K. French (A'24-M'30-

SM'43) has been appointed Chicago mana-

ger of the General Instrument Corporation.

Mr. French began

his 31 years in the

electronic field as a

development engi-

neer with Federal

Telegraph and Tele-

phone

Company.

Subsequently, he held

positions with the

American

Bosch

Company, RCA Li-

B. V. K. FRENCH

cense Division Laboratory, P. R. Mal-

lory Company, and

the Allen B. DuMont Laboratories, Inc. He

was responsible for the introduction of push-

button station selection and waveband

switching.

During World War II, Mr. French

served on the joint Army-Navy Standardiza-

tion Board; he also supervised, at Mallory,
research in developing amercury-type dry

battery, extensively used in armed forces

radio equipment.

Mr. French has served as Chairman of

the IRE Connecticut Valley and Indianapolis Sections, and is a member of the IRE Professional Group on Airborne Electronics and the Radio Club of America.

Glen B. Ransom (M'45) has been ap-

pointed assistant engineering staff manager

of the long lines department of the American

Telephone and Tele-

graph Company, New

York, N. Y.

Mr. Ransom, a

native of Marengo,

Iowa, received the

B.S. degree in electri-

cal engineering from

the University of

Minnesota in 1922.

He then joined

G. B. RANSOM

AT&T as atechnical engineer, and in 1927

became district plant engineer in Indianapolis, and division trans-

mission engineer in Cleveland in 1928. In

1930, he transferred to the engineering

headquarters in New York. Recently he has

been an engineer of plant extension.

Mr. Ransom is afellow of the American

Institute of Electrical Engineers and Eta Kappa Nu.

Kenneth A. Giffin (M '52) has been appointed district sales manager for the Los Angeles tube department of the General Electric Company.
Mr. Giffin was born in Bellaire, Ohio, on January 15,1911, and graduated from Purdue University in 1937. From 1937-1939, he was associated with the Bendix Radio Division as areceiver and aircraft radio systems engineer. From 1939-1951, he worked with the American Airlines as acommunications representative. Before joining General Electric, he was a service engineering manager for Aeronautical Radio, Inc., in Washington, D. C.
Mr. Giffin is a member of the Armed Forces Communications Association.

Philip D. Doersam (S'40-M '46-SM '50) has been named manager of East coast
operations of the Univox Corporation, Los Angeles, Calif.
Mr. Doersam was born in Pennsylvania, in 1917, and received the B.S. degree in electrical engineering from Columbia University in 1942. He studied advanced radar at the Massachusetts Institute of Technology.
From 1942-1945, Mr. Doersam was a
staff member at the MIT Radiation Labora-
tory, and in 1946, he became the acting head of the electronics laboratory at the Glenn L. Martin Company, Baltimore, Md. From 1947-1949, he was senior engineer and group leader at the Douglas Aircraft Company, Santa Monica, Calif. In 1949, he joined the Hughes Aircraft Company where
he was chief, flight test engineering, until his recent appointment.

558
Books

PROCEEDINGS OF THE I.R.E.

April

High Frequency Transmission Lines by J. de France
f2i0g6urPSeutsb..lBi6as1yhXse1id0d(.e19L$5.0.2I9).0,.bNy.tYh.e 4B0aypsaigdees,Pupbalpiesrhebrosu.n3d6.-3345 tNe.chYJn..odleogFyr,aSntcaeteisUhneivaedrsofittyheofdNepeawrtYmoernkt, oBfroeolekcltyrni,c
This is abooklet written to explain the physical behavior of high-frequency transmission lines to beginners who do not possess more than an elementary knowledge of mathematics.
The first chapter describes the main electrical quantities involved in the propagation of waves on an infinite line; the second deals with reflection on terminating loads. Following this is areview of the usual types of lines and applications and a brief introduction to waveguides.
The text is in everyday, nontechnical words and will be useful to the class of readers for which it is planned. It also will be of some interest to students with more technical background, for here we find an easily readable explanation of the elementary facts underlying the mathematical treatment of wave transmission along lines. Other presentations of this are sometimes unnecessarily abstruse and theoretical, and the author has eliminated this effect.
A. G. CLAVIER Federal TelecommunicationNsutLlaebys..,NI.ncJ..
Handbook of Engineering Fundamentals Edited by Ovid W. Eshbach
p44a0gePFuobiulnridtsehhxeA+dvxe(.1,9pN5a2ge)ews.bYyoTraJkbolh1en6s, WNai.lnedYy. f1ai2ng6ud2repsS.oangse5.s1 +XI5n8c2I.-..
$10.00.
TechOnvoildogiWc.al EUsnihvbearcshityi.s tEhveandsetaonn.ofIllN. orthwestern
This book is arevised edition of a 1936 publication. Upon approaching it with, "what function does this book serve, and hence of what use is it," the reviewer feels that the material performs avery useful purpose for the engineer and technical man. It illuminates those areas of engineering that border on chemistry and physics; areas that are apt to be considered pure theory by the practical man.
The book embraces the fields of mathematics, mechanics, aerodynamics, engineering thermodynamics, electricity and magnetism, radiation, light, acoustics, chemistry, metallic materials, nonmetallic materials, and finally, a valuable section on engineering law. How completely these subjects are covered may depend upon the size of the book; this text is of reasonable size and coverage.
Some may question the utility of an encyclopedic type of book, but to aperson who is familiar with the subjects, such a style can furnish a brief and useful review of material basic to his activity, thus saving him from wading through one or more weighty texts on the subject. Moreover, these articles have reasonably complete and up-to-date bibliographies that enable the reader to make further investigations.
Particularly noteworthy to the reviewer were the sections on "Mathematics,"

by O. W. Eshbach; "Physical Units and Standards," by Ernst Weber; and "Engineering Thermodynamics," by Milton C. Stuart. Although the section on mathematics is necessarily brief, the presentation
is clear and adequate, as are the other sections.
The reviewer noticed afew errors which may have escaped the eyes of the proof reader. On page 2-201, (a possible typa graphical error) is given the limit value of

co lim

lim (x)

--co as x-->a instead of x_,a4--, '(x)· un page 9-

59, in the electrical section, we do not find the compensation theorem mentioned; it deserves notice. On page 10-49, we note, "The parabolic horn ... is being widely used in
connection with sound motion pictures. The exponential horn ... is often used in loudspeaker units for public-address systems."
One matter which may affect the size of the book but which merits improvement is the size of the type. It is too small, not only in the normal portions of the book, but much too small in the sections devoted to illustrative examples and the like.
The book does fill aneed of the average engineer, and deserves aspecial place in his library. It is an excellent handbook, and contains interesting reading material as well.
ALBERT PREISMAN Capitol Radio EngWianseheirnigntgonIn.stDi.tuCt.e

Theory of Electromagnetic Waves, A Symposium Sponsored by the Geophysical Research Directorate, Air Force Cambridge Research Laboratories, and the Institute for Mathematics and Mechanics, New York University
p2a5g0ePsuF.bifl7ti2hshfieAgvduer.(e,s1.95N611e) Xwb1y0Y.oIrn$tk6e..r5s0Nc.i.enYc.e 1P,u3b9l3isphaegress. -Iln-vci.i,i
This book, which is a record of a symposium on electromagnetic waves held at New York University, June, 1950, presents the newest developments in electromagnetic theory on ascientific level, and reviews the more important, unsolved problems in the field.
A number of the papers deal with problems in diffraction and reflection. S. A. Schelkunoff gives an excellent review of the approximations involved in Kirchhoff's formula, and shows that it is not possible to obtain any improvement in the result by repeated applications of the formula. Approximate solutions based on the author's induction and field equivalence theorems do not suffer from this disadvantage. A paper by Levine and Schwinger discusses the diffraction of a plane wave by an aperture in an infinite screen. Two variational expressions are obtained for the far field, and it is shown that they yield approximate results which are valid over a much wider frequency range than most of the commonly used approximations. An interesting paper by Kellar and Frank gives asimple answer in closed form for the diffraction and reflection of apulse by awedge or corner.
The propagation of waves in nonhomogeneous media is considered by anumber of

authors. S. A. Schelkunoff draws attention to the fact that in determining the reflection coefficient for a finite inhomogeneous layer, difficulties can arise in approximating the finite layer with an infinite layer of apparently similar nature. N. Marcuvitz discusses the various representations of the field in a spherically stratified region. B. Friedman treats the propagation of waves in an inhomogeneous atmosphere where the dielectric constant is stratified in the radial direction. The problem of the reflection of waves from rough surfaces has been discussed by S. O. Rice and solutions obtained for slightly rough surfaces.
The book is of interest mainly to research engineers in the field of wave propagation. Due to the wide range of topics covered and use of higher mathematics, some engineers may find the book to be incoherent and difficult to read.
GEORGE SINCLAIR Sinclair Radio Labs. Ltd.
Toronto, Ont., Canada
Radio Spectrum Conservation, A Report of the Joint Technical Advisory Committee, IRE-RTMA
panyP,ublInics.h.ed330(19W5e2s)t b4y2 MStc.G,rNawe-wHiYlolrkBo3o6,k NC.omY-. 1+958-ppaaggeesin+d1e0x-+pxaigepabgeisb.li7ogfrigauprheys.-I8-8X-5p1ag.e $5a.p0p0e.ndix
This book was prepared by agroup of experts and consultants under the direction of asubcommittee of the Joint Technical Advisory Committee. It is designed both as an aid and an exhortation to those concerned with the planning and administration use of alimited and extremely valuable natural resource, the radio spectrum. For this purpose, it treats briefly in successive chapters the history of allocation, the propagation characteristics crf the various bands of frequencies, an idealized allocation based on a proper co-ordination between radio propagation characteristics and service requirements, and a critical discussion of the present allocation. The book concludes with aproposed program of "dynamic conservation," in which the planning will be done with such foresight and the administration with such flexibility as to obtain the maximum utilization of the spectrum.
In general, the treatment of the various topics is adequate for the purpose of the book and the style is suitable to those for whom the book is intended. However, differences in style are readily apparent, particularly between the various sections of the chapter on radio propagation characteristics. Some of these sections contain passages which may be somewhat difficult for the lay reader. There are some omissions and some errors, inconsistencies and duplication have been found. Space also has been devoted to certain characteristics or anomalies which are believed to be more of scientific interest than of administrative importance. These failings are neither numerous nor fatal to the purposes of the book, and are readily understandable in view of the scope and complexity of the subject matter and the extreme difficulty of preparing a brief, but complete summary thereof. It may be said

1953

Institute News and Radio Notes

559

that this is a good, informative summary, and for those who wish to pursue the subject in greater detail, sufficient references are provided.
In the idealized allocation developed in chapter 3, the propagation characteristics appear to have been correctly applied, to provide the kinds of communications needed in the various services. However, little information is given to justify the amounts of space assigned to each service, other than certain general considerations related to present occupancy. It would appear that this allocation should be viewed as a recommendation of the suitability of the various frequency bands of the spectrum for the several services, rather than a recommendation for spectrum allocations at the locations and in the amounts indicated. In the critique of the present allocations (chapter 4) acomplete and well rounded discussion is presented with the good and bad features of the present allocation, together with the reasons for the present situation. Chapter 5, on dynamic conservation, analyzes the problems incident to the substantial achievement of ideal spectrum utilization. It recognizes, at the outset, that to be effective, and in order to avail itself of changing knowledge and provide for new demands and services any program of management must be dynamic and flexible. Nine deterrents to full occupancy are discussed briefly. One other deterrent, that of present spectrum occupancy by spurious signals generated by non-ideal equipment, is not treated at this point, although the problem of harmonic emissions is included in the later discussion of technical measures by which improvements may be effected.
In summary, although one may disagree with specific passages in the book, the overall objective is good, and the subject in the main is expertly handled. It fills aneed in an area which has been all too foreign to the general public and to those whose support is needed if the program is to be successful. It is to be hoped that the book will be widely read and that it will be studied and retained for reference by all who are responsible for assuring that effective use is made of this essential resource.
EDWARD W .ALLEN, JR. Federal CommunicaWtaisohnisngCtoomnm,isDs.ioCn.
The Oxide-Coated Cathode Volume One-- Manufacture by G. Herrmann and S. Wegener
bSGpReoaeetogsrkeeGPmossau.fa.br+ntlc4yHwi4h-.eso7pSrh5taSvera.godmtFelWiai(uoaf1ninmtg9n,neh5eds1Lne)ioAex$snv1br+de5ayv.noiin0sunCi0e,iah.e.alEmpepanecNggmtmerleabsiawcn.enadrl&7.Y8ooeHfrnafgkilti,glhnueerLeeNtPsrd.o.,.s.5tYBA1.eOnrfXglf81lii14noc.3,e-
This is the first of a two-volume book previously published in 1944 in Germany. In the English translation, Dr. Wagener presents arevised book with modern views and methods; references include papers published in 1950.
Of particular interest is a statement occurring in the description of the book, printed inside the jacket: "A review of the oxide cathode is complicated by the close interdependence between manufacture on the one hand and scientific investigation on the other. Many of the measures taken during

manufacture can only be understood by virtue of their effect on the physical mechanism, whilst investigation of the physical phenomena must be based on a thorough knowledge of how to snake agood cathode. If this latter point is not taken into account, phenomena may be investigated which are certainly interesting but of little importance
for the cathodes which are actually used in commercial valves. "1
The importance of this statement can hardly be overemphasized, and it is evident in reading the complete two-volume work
that this thought has been a guiding principle in the writing of the book.
Volume Icontains five chapters, the first being a brief but interesting historical review with ageneral discussion of the types of oxide-coated cathodes.
Chapter 2, entitled, "The manufacture of the cathode before mounting in the envelope," is concerned with core-metal properties, preparation and application of the coating suspension, and a description of indirect heaters. Tables and charts are used in discussing core materials which include typical compositions of various commercial alloys used in the United States. The views expressed concerning the use of pure, un plated tungsten as abase metal are at variance with American experience; the reaction between W and BaO at normal operating temperatures is not great enough to prevent manufacture of tubes having a commercial life expectancy. Discussion of such topics as the precipitation of the carbonates, prepa-
ration of the suspension, coating methods, sintering, etc., are valuable and well handled.
Chapter 3, entitled, "Further processing of the cathode after mounting in the envelope," covers in outline the essential facts concerning the breakdown of the carbonate and activation of the cathode. Since the
theory of activation is covered in Volume II, the discussion of this topic in Volume Iis naturally limited to a brief description of practical procedures.
"The characteristics of the oxide cathode" are discussed in chapter 4, which contains sections on the measurement of temperature and thermal properties, measurement and comparison of emission values, actual values of emission and efficiency obtainable, undesirable features of the oxide cathode, and life. The section "ascertaining the saturated current from the retarding field current" seems abit unrealistic to one who has spent much time pursuing this idea experimentally, in view of the temperature gradient along the typical cathode; the description of actual tests for emission seems rather brief. Apart from these criticisms, the chapter is very useful; the sections on sparking and the effects of impurities are particularly interesting.
The final chapter describes, briefly, special cathodes that have been proposed for certain applications, including thoria and core-activated cathodes. There is a section of eleven pages on oxide cathode for gasdischarge devices that is especially good.
Despite the fact that some topics might profitably have been discussed in somewhat greater detail, physicists and engineers on experimental or production control work will
The italicizing is the reviewer's.

find this book to be an extremely worthwhile source of information.
Volume II has previously been reviewed in the PROCEEDINGS.1
GEORGE D. O'NEILL Sylvania ElectricBaPyrsoidduec,tsN.InYc..
GII...RR..5HEEG..e,,.rvvrDoom.lla..On4'40nN0,,eiapplpnpl.d,. 8"18S7T0.4h;1eW;JuaODlgxyeie,cdnee1em9-rb5Ce2o.rVa,otCole1rdu9rm5eC2eca.ttihIoIon,d,ePP.a"RoObcCy..
Dictionary of Conformal Representations by H. Kober
pf1ia7gg8u0ePreusbB.ilrni6odsa1ehdXxew9d+a13y.-(.p1$9a.N53ge.2e9)w5. bbYiyobrlkiDoog1vr9e,arpNh.yP+uYbx.lviic2a0t1piaopgnaesgs.e.sI-n4Ic4-.47.-
Conformal mapping is a utilization of the mathematical simplicity and peculiarities of the complex variable in the analysis and synthesis of the corresponding physical peculiarities of two-dimensional fields of steady flow or static flux. It is a powerful tool in many fields such as the fluid dynamics of airfoils and the electromagnetic plane waves guided by parallel conductors. In the field of electrical engineering, it is most simply applied to conduction and to separate electric and magnetic fields, all of which are examples of orthogonal potential and flux.
The fundamentals of conformal mapping have been duplicated in a number of textbooks, while the more specialized aspects have been spread over various periodicals and collected volumes. There has been a dire need for some comprehensive list and pictorial illustrations of the many problems amenable to the techniques of conformal mapping. Like integrals, there is no limit to the number of variations that would be helpful for reference.
The author of this volume has gone far toward filling this need. His compilation has the benefit of joint efforts first reported in 1944-1948, among the scientific research groups of the British Admiralty. It is a great credit to the individuals, the organization, and the publisher that this collection is now made available at a low cost to the many scientists who need it in their life work. It is bound to stimulate more application of these techniques and more original work to this end.
The book is divided into five parts. The first part is devoted entirely to the bilinear transformation and its important special cases which are completely, sometimes redundantly, treated. The remaining four parts deal with mappings obtained from algebraic functions, exponential functions, functions composed of the Schwarz-Christoffel transformation and higher transcendental (especially elliptic) functions. Proofs are omitted for brevity, while the limitations and peculiarities of each transformation are painstakingly placed in evidence. In most cases, the corresponding regions and their boundaries are shown in carefully lettered diagrams of the type which may be familiar from Appendix II of Churchill's "Introduction to Complex Variables and Applications."
In ordering the material within this dictionary, it may be unfortunate that the author, as he notes in the foreword, does not use one system exclusively. Instead, he

560

PROCEEDINGS OF THE I.R.E.

April

classifies usually according to the func-

tional form of the transformation and some-

times according to the geometry of the re-

gions involved. The inclusion of the Topo-

logical Index may be in recognition of the

physical importance of a completely geo-

metrical system of classification.

An excellent list of special notations and

nomenclature is placed in the front of the

book. A large number of references are given;

however, the practice of collecting these at

three different points in the book may be

questioned.

The minor objections noted above should

not obscure the over-all usefulness of this

large collection of mappings, gathered from

many sources and presented in a uniform

notation. The Dictionary of Conformal

Representations is highly recommended to

engineers, scientists, and applied mathema-

ticians who deal with the problems of two-

dimensional fields.

HAROLD A. W HEELER

W ALTER K.KAHN

WheGerleeart LNaebcokr,atNo.riYe.s

TV Troubleshooting and Repair Guide Book Volume Iby Robert G. Middleton
480PCuabnlailshSetd. (N1e95w2)YobyrkJo1h3.nNF.. YR.id2e0r1Ppubalgiessh+er3,-pIancg.e. index. 194 figures. 81 X11. Paper bound.
In the last five years or so, much has been written on television receiver troubles and their diagnosis. A considerable portion of this information pertains only to specific
problems and is widely scattered in various texts and trade journals.
This book, written primarily with the average television technician in mind, attempts to include as much practical information of this nature as possible under one cover. It is abook convenient for use in the service shop, and should be of considerable help in solving troubleshooting.
There are ten chapters in all, presented in an easy-to-read style. The text is well illustrated with picture-tube patterns illustrating receiver faults and applicable waveforms, together with troubleshooting charts for diagnosis and correction.
The author has tried to avoid any extensive theoretical explanations, presenting only as much theory as deemed necessary to assist in practical troubleshooting, rather than acomplete theoretical analysis of the circuits involved.
The first chapter points out, generally, the variations in circuitry which the television technician might expect to encounter in one manufacturer's receiver to another. Included are photographs of normal operating waveforms taken on specific receivers from several different manufacturers.
The remaining chapters cover possible faults which might develop in various portions of the receiver. It gives the procedure for proper diagnosis, pointers on visual alignment techniques, test equipment kinks and the problem of external interference.
The sections dealing with visual alignment procedures and the description of oscilloscope probes and their use should be particularly helpful to the uninitiated.
KENNETH FOWLER General EleScytrraiccusCeo,mNp.anYy.

Advances in Electronics, Volume IV, Edited by L. Marton lo+ifsIhS4ePLt-r.uaspbn,aMldgai1ae2srr5hdtiesonEd.nd.eW(ix2as139s+a5hsSx2ist).onp,cgabitgNayoetesne.Aw,dc1DYwa1i.od8terChmfk.iitg1chu0er.ePNsrN.ae.ts6siY.oX.n9Ia.3nlc2$.9B7,.up8Pra0ue.gbae-us
The fourth annual edition of this excellent series of papers is unchanged in purpose and format. It is regrettable, however, that the preface to volume one was not reprinted in the succeeding volumes. It states, among other things, that the book does not concern itself with electronic circuitry but with physical electronics and the principal components of electronic devices.
The seven papers contained in this edition are listed as follows:
1. "Electron Scattering in Solids," by H. S. W. Massey (68 pages). This mathematical paper discusses elastic, inelastic, and multiple scattering, also, electron energy loss and mobility concepts. It should be of considerable interest to scientists who deal
with such things as electron microscopes and secondary emission problems.
2. "The Scintillation Counter," by G. A. Morton (37 pages). This device, which evolved from the early spinthariscope, counts the scintillations (flashes) produced by nuclear radiation on aphosphor crystal. The components and applications of the counter are discussed.
3. "Fluctuation Phenomena," by Aldert Van Der Ziel (44 pages). This paper deals with "spontaneous fluctuations of electricity," which is more commonly and perhaps imprudently called noise. A mathematical discussion is presented of some of the more important problems.
4. "Electronic Digital Computers," by Charles V. L. Smith (28 pages). The author gives in some detail the components and in-
formation channels of digital computers. The SEAC and the whirlwind computers are described. Due to the nature of the science, the general information was up-to-date at the time the paper was written but is presently out of date.
5. "Modulation of Continuous-Wave Magnetrons," by J. S. Donal (67 pages). The various types of modulation, except pulse modulation, are presented.
6. "The Magnetic Airborne Detector," by Winfield E. Fromm (41 pages). This
material describes the method used during World War II to locate submarines with airborne equipment.
7. "Multichannel Radio Telemetering,"
by M. G. Pawley and W. E. Triest (28 pages). This paper gives some of the ad-
vances in the art of radio telemetering that were made during World War II. The applications are primarily of flight testing pilotless aircraft.
There is evidence that some of the papers were written in great haste. For example the Smith paper outlined the order in which it would discuss the various storage tubes, and then discussed them in a different order.
Frequent use of the first person plural is found in several papers. Also, the mathematical papers could have been improved by
including tables of symbols and a more judicious selection of type to distinguish
vectors from scalars. Although the papers lack polish in vari-
ous ways, they do present a hard core of

valuable information on a wide scale. The Massey paper may not be of interest to matriculates but most of the others are readable for those delving in various subjects. Students who participate in seminars and declamation contests will do well to investigate these papers as apossible source of subject material.
PAUL K.HUDSON UniversitUyrobfanIall.inIolils.
The Electromagnetic Field by Max Mason and Warren Weaver
fp1ia7gg8ue0rPeusBb.arlpio5psa1ehdnXewdd8ai.yx(.e$1s19N.5+e8215)w8-pYbpaoyaprgekerDbo1oiv9un.endrNedx..ePsY$u.b3+l.x3i9ic52iai8tciplopaonagtsgeh,esbso.+Iu4nnc46d.-1.' oFfouWnMidsacaxotnisoMinan.saondn Wias rarsesnocWiaetaevderwiwtihththtehe RUoncikveefreslilteyr
This treatise on the fundamental ideas of the electromagnetic field was originally published in 1929 by the University of Chicago Press and has now been made available in a reasonably priced paperbound edition by Dover Publications. As the authors specifically state in the introduction, they wanted to arrive at the field equations of Maxwell "in a way which will excite, rather than dull, curiosity, and which tends to produce that attitude toward fundamentals which must prevail before a real electron theory of electricity replaces the present electrical theory of electrons."
This is indeed the key to the organization of the book. It is assumed that Couloumb's law is essentially a statistical law applying between complexes of charges, and that its validity for two isolated charges is not established irrevocably. To build up electrostatic field concepts for ponderable bodies requires, then, very cautious examination of limits, of "conditions» at points in space where no charge is present. The concepts of continuous field vectors, charge densities, potential values, forces, and the like are critically examined. In a similar manner is treated the topic of magnetostatics as dealing basically with charges in motion; starting from the fundamental aspects of Ampere's law of force action between two currents, the vector potential is established for complexes of moving charges. Again, a critical examination is made of the concept of continuous field vectors, potential values, forces, and the like. Very brief treatment is given to actual current flow in conductors. In introducing the field equations, the authors again examine critically the continuous concepts such as the Poynting vector, and the energy densities. The theory is only carried to the establishment of the retarded potential functions and the radiation field of moving electrons.
The book is very well written, in a challenging manner, fully bearing out the intent of the authors. It is of great value to all scholars interested in the extension of the electromagnetic field concepts to areal electron theory of ponderable matter. It is, however, not in the purview of this book to give actual practical applications and we will therefore find little of direct interest to the radio engineer.
ERNST W EBER Polytechnic InstitBurtoeookflyBnr,ooNk.lYy.n

1953

PROCEEDINGS OF THE I.R.E.

561

Abstracts and References

Compiled by the Radio Research Organization of the Department of Scientific and Industrial Research, London, England, and Published by Arrangement with that Department and the Wireless Engineer, London, England
NOTE: The Institute of Radio Engineers does not have available copies of the publications mentioned in these pages, nor does it have reprints of the articles abstracted. Correspondence regarding these articles and requests for their procurement should be addressed to the individual publications, not to the I.R.E.

Acoustics and Audio Frequencies Antennas and Transmission Lines Circuits and Circuit Elements
General Physics Geophysical and Extraterrestrial Phe-
nomena Location and Aids to Navigation Materials and Subsidiary Techniques
Mathematics Measurements and Test Gear Other Applications of Radio and Elec-
tronics Propagation of Waves Reception Stations and Communication Systems Subsidiary Apparatus
Television and Phototelegraphy Transmission Tubes and Thermionics
Miscellaneous

561 562 563 565
566 567 567 569 569
570 570 571 571 572 572 574 574 576

The number in heavy type at the upper left of each Abstract is its Universal Decimal Classification number and is not to be confused with the Decimal Classification used by the United States National Bureau of Standards. The number in heavy type at the top right is
the serial number of the Abstract. DC numbers marked with a dagger 1') must be regarded as provisional.

ACOUSTICS AND AUDIO FREQUENCIES

534.15

599

Analysis of Air Vibrations in a Pipe with In-

ternal Discontinuities--J. Guittard. (Acustica,

vol. 2, no. 5, pp. 231-236; 1952. In French.) A

method of investigating the effect of various

types of discontinuity, such as cross-section

variation, using fine powder as indicator.

534.26+535.43

600

On a Multiple Scattering Theory of the

Finite Grating and the Wood Anomalies--

Twersky. (See 695.)

534.26

601

The Diffraction of Sound Pulses by an

Oscillating Infinitely Long Strip--P. J. Berry.
(Quart. Jour. Mech. Appl. Math., vol. 5, part 3,

pp. 324-332; September, 1952.) A solution is

obtained for the case of a plane pressure pulse

incident normally on an infinitely long strip of

finite width, capable of motion as a spring-sup-

ported rigid body. Numerical results are given

for the case of asharp-fronted pulse of constant

unit pressure, with graphs showing how the

mobility of the strip affects the pressure dis-

tribution on the back of it.

534.26

602

The Diffraction of a Sound Pulse by aNon-

rigid Semi-infinite Plane Screen--F. J. Berry.

(Quart. Jour. Mech. App!. Math., vol. 5, part 3, pp. 333-343; Sept. 1952.) Analysis is given for

the two-dimensional diffraction of a plane-

fronted pulse, incident normally on the screen.

Two methods of finding the pressure change

across the screen are described, both involving successive approximations. Graphs illustrate

the results obtained by one method for several

types of screen material.

534.321.9

603

Aspects of the Concentration of Ultrasonic

Energy--A. Barone. (Acustica, vol. 2, no. 5,

The Annual Index of these Abstracts and References, covering those published in the PROC. I.R.E. from February 1952, through January 1953, may be obtained
for 3s. 9d. postage included from the Wireless Engineer, Dorset House, Stamford St., London, S.E., England. This Index includes a list of the journals abstracted together with the addresses of their publishers.

pp. 221-225; 1952.) For another account see 3309 of 1952.

534.321.9: 534.845

604

Ultrasonic Absorption and Relaxation

Mechanism--A. K. Dutta. (Indian Jour.

Phys., vol. 26, pp. 279-282; June 1952.) Dis-

cussion leading to the conclusion that the ab-

sorption of elastic waves in liquids is mainly

due to africtional relaxation mechanism.

534.614

605

The Velocity of Sound in Air--J. M. A.

Lenilian. (Acustica, vol. 2, no. 5, pp. 205-212;

1952.) Pulses derived from a 13.5-kc/s trans-

mitter and a microphone receiver were dis-

played together on a double-beam cro. Coin-

cidence of the pulses could be obtained by

movement of the transmitter toward or away from the microphone, the motion being effected

by means of an accurate screw of length 1.8 m. Transmitter positions were noted for the

lst-5th and the 41st-45th coincidences, to ob-

tain five readings for the value of 40 wave-

lengths. Corrections were applied for the ef-

fects of temperature, humidity, and other less

important factors. The final value deduced

for the velocity of 13.5-kc sound waves in dry air at 273.16°K and 1013.2 mb is 331.45 +0.04

mc.

534.84

606

Review of Methods and Apparatus for

Room-Acoustics Measurements--L. Keidel. (Arch. tech. Messen, no. 200, pp. 193-196;

Sept. 1952.)

534.84: 621.396.712.3

607

The 'Pierre Bourdan' Low-Frequency

[broadcasting] Centre, Paris--Conturie. (See

825.)

534.845.1/.2

608

Sound Insulation by means of Rubber and

Steel Springs--M. L. Exner. (Acustica, vol. 2, no. 5, pp. 213-221; 1952. In German.) Good
agreement was obtained between theory and
experiment in measurements on combinations of rubber and steel springs. The high internal

damping of the rubber, whose loss factor is

about 10 times that of steel springs, results in

good insulation over the whole frequency range
investigated, 20 cps-2 kc. Mechanical filters, consisting of masses with intervening springs,

were also investigated; they were found better than simple systems above acertain critical fre-
quency, but had disadvantages at low fre-

quencies.

534.845.1/.2

609

The Mechanism of Sound Transmission

through Single-Leaf Partitions, investigated

using Small-Scale Models--A. Schoch and K.

Fehér. (Acustica, vol. 2, no. 5, pp. 189-204;

1952.) A summary is given of Cremer's results

(2904 of 1951) for transmission through plates of infinite area, and the effect of the boundaries is discussed qualitatively for the case of finite
plates. Measurements are reported, using small-scale models with corresponding highfrequency plane waves in an echo-free box of dimensions 150 X 80 X 80 cm. Results for plates of various materials, for both normal and oblique incidence, are shown graphically and
discussed.

534.846

610

Auditorium Specifically Designed for Tech-

nical Meetings--D. M. Beard and A. M.

Erickson. (Jour. Soc. Mot. l'ic. Tele. Eng.,

vol. 59, pp. 205-211; Sept. 1952.) Description

of the auditorium, seating 550, at the Naval

Ordnance Laboratory, White Oak, Md. The

effects of poly-cylindrical sections, absorbent

plaster, serrated rear wall, and padded seats,

combine to give excellent acoustic character-

istics. Additional facilities include 21 micro-

phones distributed about the room, controlled

lighting, optical-projection booth, and an

adequate telephone communication system.

534.861.4: 621.395.623.7

611

The Environment of High-Quality Re-

production--F. H. Brittain. (Wireless World,

vol. 59, pp. 2-5; Jan. 1953.) A survey of reproducer circuit requirements and auditorium

conditions to be satisfied in order to obtain the full benefit of good loudspeaker performance.

621.395.6: 621.396.712

612

Speech Input Systems for Broadcast Trans-

mitters--Hill. (See 824.)

621.395.61

613

On the Directivity of Spherical Micro-

phones--\V. Kuhl. (Acustica, vol. 2, no. 5, pp.

226-231; 1952.) The directivity patterns of

microphones with plane circular diaphragms

on the surface of a sphere were measured for

10 frequencies and compared with the patterns

computed by Schwarz (2992 of 1945) for point

microphones. Uniform response for all angles

of incidence can be obtained by adding the

voltages derived from two point microphones

located at opposite ends of a diameter of a

sphere. A frequency-response curve is calcu-

lated for acapacitor microphone with spherical

diaphragm.

621.395.623.7

614

Friction-driven

Loudspeaker--( Wireless

World, vol. 59, pp. 27-28; Jan. 1953.) A loud-

speaker whose operation depended on the at-

traction between a metal surface and a poor

conductor (e.g. agate) was designed by John-

sen and Rahbek over 30 years ago. A modern commercial public-address loudspeaker using

the same principle is described, in which a

metal band attached to the diaphragm is held in contact with a rotating cylinder coated with

562

PROCEEDINGS OF THE I.R.E.

April

a semiconductor. The power output is com-
parable with that of an amplifier-driven loudspeaker of similar size.

621.395.623.8

615

P.A. [public-addressl Systems in Generat-

ing Plants--S. C. Bartlett. (Radiotronics, vol.

17, pp. 159-164; Oct. 1952.) The special

conditions encountered in power stations are

discussed, and the design is considered of

suitable equipment to provide adequate speech

coverage to all personnel, with reply or break-

in from any point of the system.

789.983

616

The Chord Organ--A. Douglas. (Electronic

Eng., vol. 24, pp. 562-566; Dec. 1952.) De-

scription of a Hammond instrument which

produces, if desired, a chord when any single

note is pressed. Tone controls are also provided.

ANTENNAS AND TRANSMISSION LINES

621.315.2/.3

617

New Cables and Conductors of the I.K.A.

[Verwaltung flir Installationen, Kabel, Ap-

parate1--H. Güttlich and H. J. Franz. (Deutsche

Elektrotech., vol. 6, pp. 429-432; Sept. 1952.)

Data and illustrations of various cables, including flexible types, for counter-circuit, tele-

vision, HF and UHF applications.

621.392+621.315.2121.018.44

618

Mathematical Theory of Laminated Transmission Lines: Part 2--S. P. Morgan, Jr.

(Bell Sys. tech. Jour., vol. 31, pp. 1121-1206, Nov. 1952.) Part 1 (25 of January) dealt

mainly with Clogston-1 lines; the present

paper deals mainly with Clogston-2 lines, which

are composed entirely of laminated material;

both parallel-plane and coaxial lines are con-

sidered. Formulae are also derived for the general case of a line with arbitrary fractions

of space occupied by the main dielectric and

the laminations. Analysis is given for the

principal and higher modes, assuming in-

finitesimally thin laminae; the effect of finite

thickness is considered subsequently. The influence of nonuniformity of the laminations is

examined; to achieve an attenuation constant

of the order of a tenth that of a conventional

line, nonuniformities must be smaller than a few parts in 10,000. Dielectric and magnetic

losses are discussed; their magnitude is

directly proportional to frequency provided

the loss tangents do not vary with frequency.

621.392.21

619

Calculation of Transmission-Line Constants

--R. O. Kapp. (Engineering, Load., vol. 174,

pp. 315-316; Sept. 5, 1952.) Approximate

formulae are derived for the three line con-

stants, usually represented by the symbols A, B and C. Errors involved in the use of these

formulae are <0.7% for either the real or the

imaginary component of any of the constants

for line lengths up to about 600 miles. The

formulae do not involve hyperbolic functions.

621.392.21.09

620

Application Possibilities of a Surface-Wave

Mode--W. F. Gunn. (Marconi Rev., 4th

Quarter, vol. 15, no. 107, pp. 145-166; 1952.)

A summary is given of recent work on surface

waves, together with a short account of ex-

periments carried out in 1951 on a go-and-

return system of total length about 130 ft.

Relevant analysis from various sources is in-

cluded in appendices.

621.392.21.029.64

621

Microstrip--A New Transmission Tech-

nique for the Kilomegacycle Range--D. D.

Grieg and H. F. Engelmann. (Paoc. I.R.E.,

vol. 40, pp. 1644-1650; Dec. 1952.) A general

description and background theory are given

for transmission lines comprising a single wire

conductor arranged parallel to a ground plane

and for flat-strip lines of the type dealt with in

2705 of 1952 (Barrett). Practical methods of

making such lines include printing and em-

bossing.

621.392.21.029.64

622

Simplified Theory of Microstrip Trans-

mission Systems--F. Assadourian and E.

Rimai. (PRoc. I.R.E., vol. 40, pp. 1651-1657;

Dec. 1952.) An analysis is made of TEM-mode

propagation in a line comprising a wire or a

finite-width strip immersed in auniform dieleç-

tric and arranged parallel to a ground plane.

Characteristic impedance, power flow and

losses are considered. Numerical calculations

based on the theory indicate the practicability

of lines of this type at microwave frequencies.

621.392.21.029.64:621.317.3

623

Microstrip Components--J. A. Kostriza.

(Paoc. I.R.E., vol. 40, pp. 1658-1663; Dec.

1952.) Standing-wave detectors are described

suitable for making measurements on lines of

the single-conductor-and-ground-plane type

dealt with in above. The deviations from

pure TEM-mode propagation for different

constructions are assessed on the basis of the

measured values of guide wavelength. Dis-

persion and r.f. impedance are also discussed.

Voltage s.w.r. measurements are reported on

components for effecting transitions to coaxial

lines. Attenuator pads and loads, crystal

mounts, directional couplers etc. using the

same constructional basis are described.

621.392.26

624

Calculation of the Propagation Constants

of an Inhomogeneously-Filled Waveguide--

J. A. Bradshaw and L. G. Chambers. (Brit.

Jour. Appt. Phys., vol. 3, pp. 332-333; Oct.

1952.) Comment on 2114 of 1952 and author's

reply.

621.392.26

625

Diffraction of Guided Waves at Plane

Diaphragms--R. Miller. (Z. Notan., vol. 5a,

pp. 617-621; Nov. 1950.) The problem of

diffraction at a plane diaphragm is formulated

for the general case of awaveguide of arbitrary

cross-section. For the special case of a coaxial

aperture in a circular cylinder, a wave suffers

no transformation from E to H mode or vice

versa if incident parallel to the axis, but does

suffer transformation if incident in any other

direction.

621.392.26

626

The Concept and Measurement of Im-

pedance in Periodically Loaded Wave Guides

--E. T. Jaynes. (Jour. Appt. Phys., vol. 23,

pp. 1077-1084; Oct. 1952.) The theory of the

node-shift method of investigating transmis-

sion-line problems is reviewed. A definition

of impedance in a form applicable to the disk-

loaded waveguide is developed from ordinary

circuit theory by expressing the em field in

terms of aset of independent component fields.

An extension of the node-shift technique for

measuring impedance is described which in-

volves a determination of the parameters of a

coupling system.

621.396.67

627

Mutual Radiation Resistance of Aerials and

Arrays--L. Lewin. (Wireless Eng., vol. 30, pp.

24-25, Jan. 1953.) Comment on 32 of January

(Knudsen).

621.396.67

628

Theory of Electrically Short Transmitting

and Receiving Antennas--R. King. (Jour.

Appt. Phys., vol. 23, pp. 1174-1187; Oct. 1952.)

Centre-driven cylindrical aerials of length à X/ir are considered; complete quantitative

solutions are obtained by determining the dis-

tributions of current that actually satisfy the

integral equations. Components of current in

phase and in quadrature with the driving

voltage are evaluated, together with the im-

pedance, the effective length and the gain.

Quite accurate results are obtained even in a

first-order solution when the King-Middleton

method of solving Hallén's integral equation by iteration is applied correctly. The newly de-

termined values are combined with the King-

Middleton second-order results to obtain more accurate values for aerials of length à1.4

621.396.67

629

Cylindrical Aerials--R. W. P. King. (Wire-

less Eng., vol. 30, p. 24; Jan. 1953.) Comment

on 2715 of 1952 (Storm).

621.396.67:621.317.336

630

An Antenna Impedance-Measuring Instru-

ment--J. F. Cline. (PRoc. I.R.E., vol. 40,

pp. 1686-1689; Dec. 1952.) An indicating in-

strument is described which has a small

capacitive loading effect when connected di-

rectly to the terminals of an aerial. This is

achieved by isolating those conductive com-

ponents which are not part of the RF-cap cir-

cuit and operating the aerial as a receiving

aerial, so that the signal generator is some dis-

tance away and not incorporated in the meas-

uring instrument.

621.396.67:621.397.6

631

The WJZ-TV Auxiliary Antenna--J. Pres-

ton. (Tele-Tech, vol. 11, pp. 38-39; Oct. 1952.)

The emergency WJZ television aerial array

consists of four asymmetrical corner reflectors,

with X/2-dipole feed, uniformly spaced round

the conical portion at the top of the Empire

State Building and set askew in order to pre-

vent the occurrence of deep nulls in the radia-

tion pattern.

621.396.67:621.397.6

632

Aerials of Modern High-Power Television

Stations--G. Rutelli. (Alta Frequents°, vol. 21,

pp. 215-216; Aug./Oct. 1952.) Short discussion

of the radiation characteristics of the aerials at

the Sutton Coldfield and Holme Moss stations,

with reference to the theory of that type of

antenna previously published by the writer

(3331 of 1941 and 436 of 1942.)

621.396.67.001.11:517.948.32

633

Difficulties with Present Solutions of the

Hallén Integral Equation--S. H. Dike. (Quart.
Appi. Math., vol. 10, pp. 225-241; Oct. 1952.)

Dike and King (2716 of 1952) have found

serious discrepancies between experimental

values of broadside absorption gain and back-

scattering cross-section and those calculated by

the King-Middleton modification (1453 of

1946) of Hallén's first-order solution for a

cylindrical aerial. These discrepancies are here

discussed in detail and the problem is re-

examined, reference being made to the pub-

lished results of many investigators. A theory

which lends itself to practical computation of

the complete characteristics of a simple dipole

aerial does not at present seem to exist. It is

significant that the results of Van Vleck el. a/.

(3035 of 1947) for the back-scattering cross-

section of a shorted dipole agree more closely

with experiment than the first-order solutions

of Hallén, King and Middleton, or Gray (1931

of 1944). Variational methods of solving

Hallén's equation have given results which are

not satisfactory in some respects. It is con-

sidered that it might be worth while to follow

up a suggestion made by Brillouin (790 of

1945) that the known function and the kernel

of the integral equation be expanded in Fourier

series with known coefficients, and that the un-

known function for the current be expanded

likewise with unknown coefficients. Term-by-

term integration would then lead to a set of

simultaneous equations for determining the

coefficients. Results of such an approach do not

appear to have been published.

621.396.676:623.74

634

Flush-Mounted Antennas for Military Air-

craft--( Tele-Tech, vol. 11, pp. 58-59, Ill;

Oct. 1952.) Illustrations of zero-drag types of

aerial developed for jet-driven fighters and

high-speed bombers and operating at fre-

quencies from 100 mc to 1.25 kmc. Their func-

tions include distance measurement, com-

munications, landing approach, navigation,

and interrogation.

1953

Abstracts and References

563

621.396.677

635

Approximate Determination of Aerial Gain

--S. Giustini. (Alta Frequensa, vol. 21, pp.

204-214; Aug./Oct. 1952.) When side lobes are

negligible, the field-strength distribution of a

directive aerial can be represented by a single

lobe generated by rotation of the polar curve

E=E0e-hce, where Eo is the maximum field

strength and ha matching parameter. The fol-

lowing approximate expressions are derived for

the gain: G ^--·· 8h :G 2.75/(e) 2,where gb' is the

angle (in radians)_corresponding to a field

strength of Eo/V2.

621.396.677.029.62

636

U.S.W. Wide-Band Directive Aerial--H.

Bosse. (Fernmeldetech. Z., vol. 5, pp. 437-439;

Oct. 1952.) Description of an aerial system con-

sisting of a vertical stack of four pairs of

horizontal X/2 dipoles. The dipoles of each pair

are arranged in line, and behind the whole

system at adistance of about 0.3 Xis apolariz-

ing reflector grid of 20 horizontal rods. Effec-

tive bandwidth is 27 mc, centred on 54.5 mc.

621.396.67

637

Antennas: Theory and Practice. [Book

Review[--S. A. Schelkunoff and H. T. Friis.

Publishers: J. Wiley and Sons, New York,

1952, 593 pp., $10. (Paoc. I.R.E., vol. 40, p.

1742; Dec. 1952.) A complete text, intended

for students, radio engineers and applied mathematicians and physicists; the mathe-

matics does not go beyond the calculus.

CIRCUITS AND CIRCUIT ELEMENTS

621.3.014.1:537.311.2

638

Ohm's Law for Build-up Phenomena--V.

Kussl. (Funk u. Ton, vol. 6, pp. 527-533; Oct.

1952.) In the case of 2-pole networks, the La-

place transformation is applied in the form of

a Fourier integral of the input waveform.

Doetsch's symbolic notation for asymmetrical

transformations (3450 of 1948) is used, and the

equality sign of Ohm's law is replaced by the

Doetsch transformation sign. The variation

with time of a current through a complex im-

pedance is given by the Laplace transform

product of the susceptance and the applied-

voltage spectrum. Application of the trans-

formation in quadripole theory is described. By

formulating the quadripole equation in chain-

matrix form, transient-response parameters

can be roughly estimated. Application of the

theory to the determination of transient dis-

tortion in communication systems and to the

stability testing of amplifiers is outlined.

621.3.015.7: 621.387.4

639

Pulse-Amplitude Analysis in Nuclear Re-

search--A. B. Van Rennes. (Nucleonics, vol.

10, pp. 20-27, 22-28, 32-38 and 50-56; July-

Oct. 1952.) Various voltage-discrimination

techniques are discussed in detail and de-

scriptions are given of asimple type of analyser

and a moderate-precision and a high-precision

analyser. Analysers are also discussed in which

pulse-height selection is effected either by

mechanical means or by use of diode valves,

trigger circuits, sorting-ladder circuits, or

beam-deflection techniques. Other types of

analyser described include those in which

height selection is accomplished (a) by an ex-

pander-amplifier driving achain of discrimina-

tors, (b) by conversion of pulse amplitude to

pulse duration, (c) by means of information-

storage devices. 55 references.

621.314.25

640

Low-Cost Variable Phase Shifter--S. Wald.

(Electronics, vol. 25, pp. 168, 180; Dec. 1952.)

The basis of the circuit is a linear resistance

potentiometer divided by tappings into four

equal sections, neighbouring sections being fed,

by a pair of transformer secondaries, with

voltages phase-separated by 90°. The value of

the potentiometer resistance is not critical, pro-

viding it is large compared with the impedance

of the transformer secondaries.

621.314.7:621.396.6

641

Dynamics of Transistor Negative-Resist-

ance Circuits--B. G. Farley. (Puoc. I.R.E.,

vol. 40, pp. 1497-1508; Nov. 1952.) A general

method is presented for calculating approxi-

mately the characteristics of nonlinear cir-

cuits. The region of operation is divided into

subregions, within each of which the circuit

may be considered as nearly linear. The

method is applied to (a) analysis of a highspeed switching circuit using a point-contact

transistor, (b) discussion of negative-resistance

relaxation oscillations, (c) calculation of wave-

forms and rise times of aregenerative transistor

amplifier [769 below (Felker)].

621.314.7: 621.396.6: 512.831

642

Matrix Representation of Transistor Cir-

cuits--J. Shekel. (Paoc. I.R.E., vol. 40, pp.

1493-1497; Nov. 1952.) Transistor circuits are

discussed in terms of measurable quantities

only. Once the admittance matrix of the

grounded-base transistor has been determined,

the matrices of the grounded-emitter and

grounded-collector transistors can easily be

derived. Matrix representation also provides a

direct method for analysis of stages in cascade.

621.314.7: 621.396.6: 621.396.822

643

Transistor Noise in Circuit Applications--

H. C. Montgomery. (Puoc. I.R.E., vol. 40, pp. 1461-1471; Nov. 1952.) Problems of linear

circuits involving multiple noise sources can be

handled by familiar methods with the aid of

certain noise-spectrum functions, which are

described. Several theorems of general interest

in circuit work, dealing with noise spectra and

noise correlation, are derived. The noise

characteristics of transistors can be described

in terms of the spectrum functions for simple

but arbitrary configurations of equivalent

noise generators. From these, the noise figure

can be calculated for any external circuit.

Numerical results for a number of n-p-n tran-

sistors are given in a table and many curves.

621.314.7.012.8

644

Junction-Transistor Equivalent Circuits

and Vacuum-Tube Analogy--L. J. Giacoletto.

(Paoc. I.R.E., vol. 40, pp. 1490-1493; Nov.

1952.) A comparison is made between the

operating characteristics of a p-n-p-junction

transistor and a triode tube, using a II net-

work to represent the transistor.

621.316.8+621.318+621.319.41.001.8

645

Nonlinear Circuit Elements in HighFrequency and Low-Frequency Technology--

H. E. Hollmann. (Arch. elekt. übertragung, vol. 6, pp. 434-440, 478-486 and 520-531;

Oct.-Dec. 1952.) A review of the properties and applications of nonlinear inductors, capaci-
tors and resistors of many different types. See

also 3039 of 1952.

621.316.842:621.316.7

646

New Commercial Barretters--J. Sommer.

(Funk u. Ton, vol. 6, pp. 520-526; Oct. 1952.)

The characteristics of two tungsten-coil bar-

retters are given. The resistances when cold

are respectively 500 and 10011; a current of

about 5mA doubles the resistance in each case.

Tests to determine the cooling characteristics

and the effect of ambient-temperature changes

are described.

621.318.4

647

Coil Winding Data--L. Knight. (Wireless

World, vol. 59, p. 22; Jan. 1953.) Charts give

the number of turns required in conjunction

with various values of capacitance for tuning

over the frequency ranges 2-70 mc and

70 kc/s-3 mc, using standard formers with dust

cores.

621.318.57

648

New Bistable High-Speed Multi-Purpose

[switching] Device--V. Druet (C.R. Acad.

Sc., Paris, vol. 235, pp. 494-496; Aug. 1952.)

Operating renditions for an Eccles-Jordan

circuit using two Type-ECH42 triode-hexode valves are noted. With suitable diode limiting, consistent operation is maintained at pulse
rates >2 X 10,/sec.

621.318.57:621.3.015.7

649

Arithmetical Counters for Pulses--A.

Dauphin. (Onde Ilea., pp. 459-463; Nov.

1952.) A list is given of 51 relevant publications,

with short notes indicating their scope.

621.318.57:621.314.7

650

A Transistor Reversible Binary Counter--

R. L. Trent. (Paoc. I.R.E., vol. 40, pp. 15621572; Nov. 1952.) The counter is built of ele-

mentary transistor packaged units. The

mechanism used to achieve reversibility and the

circuit for each type of building block are de-

scribed.

621.318.57:621.314.7

651

Transistor Trigger Circuits--A. W. Lo.

(Paoc. IRE., vol. 40, pp. 1531-1541; Nov.

1952.) Analysis is presented for transistor trigger circuits which permits prediction as to

whether operation will be monostable, bistable

or astable (oscillatory) and also of the ampli-

tude and waveform of the output. Practical

pulse circuits for various purposes are described which are so designed that their operation is

not affected by reasonable variations of,circuit

parameters, bias voltages, transistor charac-

teristics, or ambient temperature.

621.318.57:621.314.7

652

Transistors in Switching Circuits--A. E.

Anderson. (Bell Sys. Tech. Jour., vol. 31, pp.

1207-1249. PROC. I.R.E., vol. 40, pp. 1541-

1558; Nov. 1952. Correction, ibid., vol. 40,

pp. 1732-1733; Dec. 1952.) Analysis of

transistor trigger circuits is based on an ap-

proximate representation of the negative-

resistance characteristic by three straight lines. Circuits using point-contact transistors

for waveform generation, level restoration,

delay, storage, and counting are described, and

their properties and limitations are discussed

In detail.

621.318.57:621.314.7:518.4

653

Graphical Analysis of Some Transistor

Switching Circuits--L. P. Hunter and H.

Fleisher. (Paoc. I.R.E., vol. 40, pp. 1559-1562;

Nov. 1952.) Methods are described for generat-

ing the entire input characteristics for the

various terminals of atransistor, and graphical

methods of analysis are applied to (a) a base-

input amplifier, (b) a collector-to-emitter

direct-coupled switching circuit, (c) acollector-

to-base direct-coupled circuit.

621.318.572

654

Electronic Switch--K. R. Sturley. (Wireless World, vol. 59, pp. 11-14; Jan. 1953.) A

switching circuit for two-waveform display

with a single-beam cro uses a conventional multivibrator for generating the switching

voltages.

621.392

655

Network Analysis by Repeated Voltage

Superposition--J. E. Parton. (Electronic Eng., vol. 24, pp. 570-574; Dec. 1952.) A method of

analysis is described, with worked-out ex-

amples, which reduces considerably the number

of simultaneous equations to be solved for an m-mesh network. The method essentially in-

volves successive applications of Thévenin's

theorem, each application reducing by one the

number of meshes in the network considered,

with a corresponding reduction of the number

of simultaneous equations to be solved. A

similar method has been described by Teeny-

Tschiassny (3365 of 1948), who used "residual"

current generators at the final nodes instead of residual voltage generators in the final

branches, and whose method differs from the

present method in other details.

621.392

656

Synthesis of Cascaded Three-Terminal

564

PROCEEDINGS OF THE I.R.E.

April

RC Networks with Minimum-Phase Transfer Functions--P. F. Ordung, F. Hopkins, H. L.
Krauss and E. L. Sparrow. (Pftoc. I.R.E., vol. 40, pp. 1717-1723; Dec. 1952.) For the realization of a particular transfer function including complex zeros, the method of synthesis
presented yields anetwork with fewer elements, simpler configurations and higher level of
transmission than previous methods (e.g. 1605 of 1950).

621.392.1

657

The Practical Significance of Complex

Frequencies in Electrical Communication

Engineering--J. Peters. (Arch. elekt. über-

tragung, vol. 6, pp. 401-413; October 1952. Cor-

rection, ibid., vol. 6, p. 514; Dec. 1952.) A con-

cise general introduction to thesubject. Complex

frequencies are complex quantities whose real

part represents the gain of asystem and whose imaginary part represents the frequency in the

usual sense. The application of the Laplace

transform in analysis of transmission problems

is explained and the properties of the complex

plane and its poles and zeros are described.

The use of the poles and zeros for representa-

tion of the transmission characteristics of a

linear network is considered. Analogues of the

complex plane, such as that obtainable with a

stretched elastic membrane, are discussed and

their applications illustrated.

621.392.4/.5

658

Anode-Follower Derivatives--A. W. Keen.

(Wireless Eng., vol. 30, pp. 5-9; Jan. 1953.)

"Low output-impedance stages characterized

by anode output and feedback of the entire

output voltage are derived from the basic 'anode-follower' by substitution of a tube

impedance for the shunt resistor of the feed-

back path, or of a comparator stage for the

entire input-feedback potential divider, and by

replacement of the output tube by a series-

connected push-pull pair. These developments

suggest the possibility of obtaining an anode-

follower analogue of each cathode-follower

derivative, thereby increasing the number of circuit variants available for practical use."

621.392.4/.5:512.972

659

Applications of Tensor Theory to Linear

Electronic Circuits--A. Kaufmann. (Radio

Lech. Dig. (France), vol. 6, nos. 2, 3and 4, pp.

67-76, 157-168 and 199-209; 1952.) An ex-

planation of tensor concepts and their general

application to tube circuits, with examples il-

lustrating the determination of input imped-

ance and gain of feedback, cathode-follower,

and grounded-grid circuits.

621.392.5

660

On the Approximation Problem in Network

Synthesis--A. D. Bresler. PROC. I.R.E., vol.

40, pp. 1724-1728; Dec. 1952.) A method of

synthesis is presented in which a desired fre-

quency-response characteristic is replaced by

an approximation consisting of a sequence of

rectilinear segments. The method is illustrated

by application to the design of attenuation

equalizers with constant-resistance ladder

sections.

621.392.5

661

The Parallel-T Resistance-Capacitance

Network--L. G. Cowles. (Paoc. I.R.E., vol.

40, pp. 1712-1717; Dec. 1952.) Analysis is

given for the general case of finite source and load resistances. When these two resistances

are appropriately related the network loss is

the same at low and high frequencies; the

transfer characteristic is then a circle in the

complex plane. This "symmetrical" network is

equivalent to a simple series-resonant circuit

as regards its transfer characteristic.

621.392.5

662

RC Cathode-Follower Feedback Circuits--

S. C. Dunn. (Wireless Eng., vol. 30, pp. 10-19;

Jan. 1953.) When certain RC circuits are as-

sociated with a cathode-follower circuit, a

voltage gain can be obtained over a band of
frequencies. A number of prototype and
derived RC circuits which can be used in this way are analysed and their response curves are determined. The matrices of the derived net-
works can be formed easily from those of the
corresponding prototypes. The effect of cir-
cuit termination on response is discussed and the use of these circuits as feedback elements in amplifiers is considered in some detail. Experiments in confirmation of the theory are mentioned.

621.392.5

663

Resistance-Capacitance Networks with

Over-Unity Gain--W. Bacon and D. P. Sal-

mon. (Wireless Eng., vol. 30, pp. 20-23; Jan.

1953.) Longmire (2702 of 1947) and Epstein (2940 of 1951) have described RC circuits with

greater output than input voltage. A method of increasing the voltage gain by feeding the output voltage of one network into a second

network is described. The process cannot be extended indefinitely, the voltage gain attain-

able being limited by the impedance increase necessary at each stage. Experiments con-

firmed the theory. Such networks can be used with acathode follower to construct oscillators

in which the valve gain is less than unity. An experimental circuit is described.

621.392.5

664

Response of a Linear Network to an Input

with Linearly Variable Frequency as obtained

in Sweep-Frequency Testing--H. Ekstein and

T. Schiffman. (Proc. not. Electronics Conf.,

Chicago, vol. 7, pp. 454-471; 1951.) Application

of an input voltage with linearly increasing

frequency to a linear network produces an

output curve which, for very slow frequency

variation, is an image of the admittance

plotted as a function of frequency. When the

rate of frequency variation is not negligible, the

response curve is a distorted image of the ad-

mittance. The nature of this distortion is in-

vestigated. A quantitative approximation

method is presented which uses the theory of

functions for evaluation of an integral. The

result is expressible in terms of elementary

functions. Explicit expressions are given for

the dynamic corrections to be applied to the

"observed" resonance frequencies and peak

admittances. The method is applied to several

simple circuits in addition to the LCR circuit

which has been previously treated by other authors.

621.392.52

665

Fundamentals of Filter Theory and Tech-

nique--K. H. Haase. (Funk u. Ton, vol. 6,

pp. 505-519; Oct. 1952.) Description of the

application of the wave theory and the operat-

ing-parameter theory in the design and cal-

culation of different basic types of filter.

621.392.52

666

Formulas for Ladder Filters--H. J.

Orchard. (Wireless Eng., vol. 30, pp. 3-5; Jan.

1953.) Four related sets of explicit formulas for

the elements of a basic low-pass filter network

are presented with a common notation. Three

of the sets have been published previously

[2900 of 1937 (Norton); 1543 of 1952 (Bosse);

1541 of 1952 (Belevitch)], the fourth being

new; all have reference to the image-parameter theory due to Norton and Darlington (1361 of

1940). If corresponding formulae could be

found for ageneral type of filter with response

depending on Jacobian an elliptic functions,

they would represent a considerable contribu-

tion to filter-design technique.

621.392.52

667

A Nonlinear Statistical Filter--A. W.

Sullivan and J. M. Barney. (Proc. Nat. Elec-

tronics Conf., Chicago, vol. 7, pp. 85-91; 1951.)

A method is described for using the statistical

differences between a periodic rectangular

pulse (the wanted signal) and the envelope of

fluctuation noise (the interfering signal), for

the purpose of discriminating between the two signals. Expressions are derived for the density distribution probability of noise and of signal
plus noise. A description is given of apractical filter which was checked experimentally under conditions when the signal was completely
masked by the noise, both aurally and visually, but could be reliably detected by means of the statistical filter. Possible application to secret-transmission systems is discussed.

621.392.52: 518.12

668

Numerical Calculation of Filter Circuits with Tchebycheff Characteristics after the

Method of W. Cauer--V. Fetzer. (Arch. elekt.

übertragung, vol. 6, pp. 419-431; Oct. 1952.)

Formulas for Tchebycheff-type filters are

derived from those previously given for

filters with generalized parameters (1545 of

1952.) Three types of antimetrical filter are

considered. The formulas necessary for nu-

merical calculation of both symmetrical and antimetrical normalized filters are derived and

applied to examples. By suitable frequency

transformation the normal type of Tchebycheff

filter can be dealt with. A complete set of

curves is provided for evaluation of the required parameters.

621.392.52:621.315.212

669

Coaxial Transmission-I inc Filters--D. E.

Mode. (Paoc. I.R.E., vol. 40, pp. 1706-1711;

Dec. 1952.) Analysis for coaxial-line band-pass

filters is given based on TEM-mode transmis-

sion. The influence of the nature and spacing

of the obstacles on the bandwidth is discussed.

Measurements on filters of various construc-

tions support the theoretical results. A TE-

mode high-pass filter is also discussed. For narrow-band applications this type of filter is

inferior to the cavity type.

621.392.52:621.396.49

670

Nonlinear Filtering and Waveshape Multi-

plexing--R. E. Scott, S. Fine and A. Mac-

mullen. (Elearonics, vol. 25, pp. 146, 148; Dec.

1952.) A method of providing two channels on

one carrier consists of differentiating the com-

bined signal, clipping to remove one com-

ponent, and re-integrating to restore the other.

The removed component is recovered by sub-

tracting the retained component from the

original input. Experimental circuits and wave-

forms obtained are illustrated, the two com-

ponents being respectively a sine wave and a

square wave.

621.394/.3961.6: 003.63

671

Functional Circuit Diagrams--C. E. Wil-

liams. (Wireless World, vol. 59, pp. 19-21; Jan.

1953.) Shortened version of paper abstracted in 63 of January.

621.396.6: E21.314.7: 629.13

672

Transistors in Airborne Equipment--O. M.

Stuetzer. (Pitoc. I.R.E., vol. 40, pp. 1529-1530;

Nov. 1952.) Discussion of the advantages of

using transistors instead of valves in aircraft

equipment.

621.396.6:621.317.755

673

Slow-Speed Circular Timebase--(Radio

Tech. Dig. (France), vol. 6, no. 4, pp. 179-193;

1952.) French version of paper by Hardie and

Thomas (2755 of 1952) supplemented with references and a note on earlier types of sine-

cosine potentiometer.

621.396.6.002.2:621.314.7

674

Printed Circuitry for Transistors--S. F.

Danko and R. A. Gerhold. (Paoc. I.R.E., vol.

40, pp. 1524-1528; Nov. 1952.) The auto-

sembly technique [355 of February (Danko)] is

suggested as a simple and effective method for the production of compact transistor circuits.

621.396.611.1

675

Resonance Curves--"Cathode Ray."

(Wireless World, vol. 59, pp. 29-33; Jan. 1953.)

Deviations encountered in practical circuits

1953

Abstracts and References

565

from the ideal conditions dealt with in elementary theory are simply explained.

621.396.611.1 :621.396.822

676

Spontaneous Voltage Fluctuations in a

Resonant Circuit--E. Paolini. (Alta Fre-

quenza, vol. 21, pp. 199-203; Aug./Oct. 1952.)

The rms value of voltage fluctuations, of

thermal origin, at the terminals of a parallel

RLC circuit, is determined for the unusual

case where the frequency range in question is

not negligible in comparison with the band-

width of the resonant circuit. Curves are given

to facilitate numerical calculation.

621.396.615+621.396.6451:621.314.7

677

A Junction-Transistor Tetrode for High-

Frequency Use--R. L. Wallace, Jr., L. G.

Schimpf and E. Dickten. (Pxoc. I.R.E., vol.

40, pp. 1395-1400; Nov. 1952.) Application of

suitable bias to afourth electrode connected to

the p-type central section of an n-p-n-junction

transistor causes a considerable reduction of

the base resistance. This reduction enables the

transistor to be used at frequencies over ten

times the normal limit. Circuits are given for a

variable-frequency tuned amplifier, a band-

pass amplifier, and a sine-wave oscillator for

40-115 mc.

621.396.615:621.314.7

678

Transistor Oscillators--W. Herzog. (Arch.

elekt. übereragung, vol. 6, pp. 398-400; Oct.

1952.) The characteristics of transistor oscilla-

tors are established by analysis in which the

conductance form of the transistor equations

is used. The following circuits are considered:

(a) transistor with frequency-determining

quadripole and overall feedback; (b) as in (a)

but with transformer coupling between transis-

tor and quadripole; (c) transistor oscillator

with a II-arrangement of three parallel-

connected tuned circuits.

621.396.615.029.4: 621.314.7

679

Low-Drain Transistor Audio Oscillator--

D. E. Thomas. (Paoc. I.R.E., vol. 40, pp.

1385-1395; Nov. 1952.) Description of the

design and performance of a 130-c/s oscillator

using a Western Electric Type-A1768 point-

contact transistor supplied from a single 6-V

battery, the power drain from which does not

exceed 35 mW.

621.396.615.11

680

A Low-Frequency Function Generator--

R. H. Brunner. (Electronics, vol. 25, pp. 114-

117; Dec. 1952.) Description of a relaxation

oscillator capable of giving a constant-ampli-

tude output of sine, square or triangular wave-

form, in the frequency range 0.01 cps-1 kc.

621.396.615.12.078

681

Automatic Tuning Control of H.F. Genera-

tors with Varying Load--H Hertwig. (Elec-

tronic Appl. Bull., vol. 13, pp. 9-18; Jan. 1952.)

The phase relation between the primary

voltage and the secondary current of the out-

put transformer of a crystal-driven 40-mc

500-W generator is used for automatic control

of the tuning of the output circuit under vary-

ing load conditions. Control is effected via a

bridge type of phase-measurement unit using

apair of Type-EQ80 enneodes, which acts on a

control unit using a pair of Type-PL21 thyra-

trons. Circuit details, photographs and per-

formance figures are given.

621.396.615.17:621.314.7

682

Pulse Duration and Repetition Rate of a

Transistor Multivibrator--G. E. McDuffie, Jr.

(Paoc. I.R.E, vol 40, pp 1487-1489; Nov.

1952.) Expressions are derived for the pulse

duration and repetition rate of an astable

(oscillatory) multivibrator circuit using a

point-contact transistor. The formulas are

confirmed experimentally for repetition rates

from 200 to 10,000 per sec and pulse durations

from 30 to 900 ps.

621.396.619.13:621.318.4

683

Variable Inductance and its Application in

Frequency-Sweep Oscillators --W. Lange.

(Funk u. Ton, vol. 6, pp. 534-540; Oct. 1952.)

The modulation principle described consists in

varying the voltage across an inductor /..1

while the current through it is maintained con-

stant. Alternations of the control-grid voltage

of a pentode cause anode and screen-grid cur-

rents to vary in magnitude, developing a volt-

age variation across an anode inductor L2,

coupled to the inductor L1 in the cathode

circuit. The current through Li is maintained

constant by an alternating voltage applied to

the suppressor grid. A frequency shift of ±20%

around 470 kc is attainable. The use of the

method for f.m. and frequency-sweep tuning

is indicated.

621.396.622.7:621.396.619.13

684

Double-Counter FM and AFC Discrim-

inator--J. J. Hupert, A. Przedpelski and

K. Ringer. (Electronics, vol. 25, pp. 124-125;

Dec. 1952.) A frequency discriminator with

large bandwidth and good stability comprises

a pair of pulse-counter circuits, each preceded

by mixer and pulse-forming circuits, with their

outputs connected in series.

621.396.645+621.396.615

685

Vacuum-Tube Circuits without Plate Sup-

plies--P. B. Clark. (Electronics, vol. 25, pp.

192, 199; Dec. 1952.) The existence of thermal

emf and contact potential makes circuit

operation possible without application of volt-

age to tube anodes. A limiter, a low-gain

amplifier, a multivibrator and an oscillator

circuit are described.

621.396.645

686

Volume Compression and Expansion--

B. D. Corbett: G. J. Pope. (Electronic Eng.

vol. 24, p. 580; Dec. 1952.) Comment on 365

of February and author's reply.

621.396.645:621.313.2.026.441/.4421-9

687

Calculations for a Power Amplifier for a

D.C. Motor--J. Zakheim. (Onde elect. vol. 32,

pp. 455-458; Nov. 1952.) The design is con-

sidered of valve circuits for driving low-

power motors (5-15W), such as are often used

in control or telemetry equipment.

621.396.645: [621.314.7

688

Transistor Operation: Stabilization of Op-

erating Points--R. F. Shea. (Pace. I.R.E., vol.

40, pp. 1435-1437; Nov. 1952.) The provision

of optimum emitter and collector bias currents

for a transistor amplifier is discussed, and a

relation between the values of resistors and

voltages is derived which should be satisfied

if stable operation is to be achieved.

621.396.645:621.314.7

689

Transistor Amplifier Cut-Off Frequency--

D. E. Thomas. (Psoc. I.R.E., vol. 40, pp. 1481-

1483; Nov' 1952.) The effect of the positive

feedback associated with the internal base

resistance of a transistor on its cut-off fre-

quency is analysed. Expansion of the expression

for current gain a in aTaylor series shows that

only the phase shift in a is important in reduc-

ing the cut-off frequency.

621.396.645:621.314.7

690

Frequency Variations of Current-Amplifi-

cation Factor for Junction Transistors--R. L.

Pritchard. (Paoc. I.R.E., vol. 40, pp. 1476-

1481; Nov. 1952.) In a grounded-emitter or

grounded-collector connection of a junction-

type transistor, the effective current amplifica-

tion is proportional to 1/(1--a), where a is

the current gain of the transistor. As a result

of the phase shift associated with a, the value

of 1/(1--a) decreases rapidly with increasing

frequency, so that the upper frequency limit

of the grounded-emitter or grounded-collector

arrangements may be considerably lower than

has been expected. Results of measurements

,of the frequency variation of afor several fused-

impurity p-n-p-junction transistors developed by Saby (877 below) are shown graphically.

621.396.645:621.387.4

691

The Reproduction of Voltage Pulses by

means of a Proportional Amplifier--U. Cap.

relier. (Z. angew. Phys., vol. 4, pp. 330-343;

Sept. 1952.) Analysis of an amplifier for

nuclear-physics investigations is based on

Laplace transformations. A characteristic

transmission function is introduced which

completely describes the transmission proper-

ties of the amplifier and represents the com-

bined pulse-distorting influences of the indi-

vidual circuit elements. The transmission

functions of single-stage and multistage ampli-

fiers are derived and a detailed exposition is

given of the distortion experienced by atypical

exponential decay pulse. Optimum reproduc-

tion of such a pulse requires a particular rela-

tion between pulse duration and the time con-

stants of the amplifier circuits. Improvement

of time-resolution involves closer restriction of

this relation and greater complexity of circuits.

Use of negative feedback offers advantages; a

two-stage feedback amplifier is a useful unit

in a large amplifier system. The transmission

function can alternatively be determined from

the response of the amplifier to steady alter-

nating voltage; a suitable method of measure-

ment is described.

621.396.645.371.029.45

692

A Photocell Amplifier for Infra-Red Spec-

troscopy--D. A. H. Brown. (Jour. Sci. Inst.,

vol. 29, pp. 292-294; Sept. 1952.) Description

of ahighly linear amplifier for use at achopping

frequency of 800 c/s. Gain variation is <i%

for 10% variation of supply vloltage.

621.396.822

693

Symposium on Noise. General Introduc-

tion--H. B. G. Casimir. (TUdschr. ned.

Radiogenoot., vol. 17, pp. 199-206; Sept./Nov.

1952.) Discussion of the mathematical repre-

sentation of noise.

GENERAL PHYSICS

534.01 + 538.561: 621.319.55

694

A Coherent Theory of Relaxation Phe-

nomena--E. Hiedemann and R. D. Spence.

(Z. Phys., vol. 133, pp. 109-123; Sept. 5, 1952.)

The theory presented is based on the theory of

functions. General formulas are derived and

the particular case of elastic relaxation oscilla-

tions is discussed. Conditions for the occur-

rence of discrete and of continuous relaxation

spectra are determined and a formula is de-

rived for the distribution function of the con-

tinuous spectrum.

534.26+535.43

695

On a Multiple Scattering Theory of the

Finite Grating and the Wood Anomalies--V.

Twersky. (Jour. Appl. Phys., vol. 23, pp. 1099-

1118; Oct. 1952.) The problem is treated by

applying the solution previously obtained

(2685 of 1952) for multiple scattering from an

arbitrary configuration of parallel cylinders.

Both the transmission grating and the reflec-

tion grating comprising semicylindrical bosses

on aperfectly conducting plane are considered.

The complete expression for the scattered

wave is given for the case of grating width

small compared with distance to observation

point and cylinder spacing large compared

with X. The case of radii«X is investigated in

detail; bright and dark hands in the intensity

curves, similar to the grating anomalies found

by Wood in 1902, are related to the magnitudes

and phases of the various orders of scattering.

The theory is extended to gratings with ele-

ments other than cylinders.

535.42.001.11

696

Removal of Inconsistency in the Theory of

Diffraction--D. S. Jones. (Proc. Comb. Phil.

Soc., vol. 48, part 4, pp. 733-741; Oct. 1952.)

In certain cases the integral equations involved

566

PROCEEDINGS OF THE I.R.E.

April

in analysis of the diffraction of small-amplitude acoustic or e.m. waves give a solution which does not satisfy the boundary conditions im-
posed, but which agrees with the solution found by other means. This inconsistency is removed if different boundary conditions are imposed in the formulation of the problem; this is illus-
trated by discussion of two-dimensional diffraction of a plane e.m. wave by a perfectly con-
ducting semi-infinite plane.

537.12

697

The Rydberg Constant and the Atomic

Mass of the Electron--E. R. Cohen. (Phys.

Rev., vol. 88, pp. 353-360; Oct. 15, 1952.)

Re-evaluation of the spectroscopic data perti-

nent to the Rydberg constant and the mass of

the electron yields the values R.,=109737.326

±0.014 cm-1 and nt (54.895 +0.008)X 10-6

atomic mass units. From microwave measure-

ments nt (54.8785 ±0.0019) X 100-6 a.m.u. and

109737.311 ±0.012 cm-1.Houston's and

Chu's data can be brought into agreement

with those of Drinkwater, Richardson and

Williams by assuming differences in the wave-

length standards used.

537.226.2/.3:541.135

698

Dielectric Dispersion in Pure Polar Liquids

at Very High Radio Frequencies: Part 3--

The Effect of Electrolytes in Solution--J. A.

Lane and J. A. Saxton. (Proc. Roy. Soc. A,

vol. 214, pp. 531-545; Oct. 1952.) A description

is given of measurements, at mm and cm

wavelengths, of the absorption of electrolytic

solutions, of concentrations up to 3N, water

and methyl alcohol being used as solvents. The

results obtained are analyzed in terms of

Debye's theory of dispersion in a polar dielec-

tric, and modifications of the theory necessary

to take account of the ionic conductivity of an

electrolyte are indicated. Measurements on

aqueous solutions of NaCl are discussed in

relation to Hilckel's theory of electrolytic

solutions. Part 2: 3400 of 1952.

537.228.1:548.0

699

Piezoelectricity, Ferroelectricity, and Crys-

tal Structure--A. von Hippel. (Z. Phys., vol.

133, pp. 158-173; Sept. 15, 1952. In English.)

By visualizing polar crystals as a network of

permanent dipole moments, the piezoelectric

and ferroelectric properties of dielectrics may

be deduced from considerations of molecular

symmetry. This approach is used to clarify the

relation between the sphalerite (cubic) and

wurtzite (hexagonal) structures, the ferroelec-

tric feedback effect in BaTiOs, aspects of

domain formation, and the interrelation be-

tween ferroelectiricity and piezoelectricity.

537.311.1:538.632

700

Carriers of Electricity in Metals exhibiting

Positive Hall Effects--S. Brown and S. J.

Barnett. (Phys. Rev., vol. 87, pp. 601-607;

Aug. 1952.) Measurements on samples of Mo

and Zn, made by an inertia method, showed

the sign of the charge:mass ratio of the car-

riers to be negative, the mean value of over 100

measurements being within 3% of the value

for free electrons.

537.523/.527

701

Electrical Discharges in Gases--F. J.

Jones. (Nature, Load., vol. 170, pp. 601-603.

Oct. 1952.) A summarized account of six papers,

with discussion, presented at a meeting of

Section A (Mathematics and Physics) of the

British Association, Belfast, September 1952.

537.523/.5251:546.292:538.56.029.63

702

High-Frequency Breakdown in Neon--

A. D. MacDonald. (Phys., Rev., vol. 88, p.

420; Oct. 1952.) Preliminary report of the

results of measurements of breakdown fields

for cylindrical cavities of heights 0.317 and

0.634 cm. over the pressure range 0.5-300 mm

of Hg. A detailed report is to be published in

the Canadian Journal of Physics.

537.525

703

An Explanation of the Extremely Low Nor-

mal Running Potential of a High-Frequency

Discharge between Plane Plates--F. Schneider

(Z. angent Phys., vol. 4, pp. 324-325; Sept.

1952.) A tentative explanation is provided by

taking account, in the equation of electron

motion, of a restoring force indicated by

plasma diffusion theory.

537.533.75

704

Chromatic Losses of Electrons in Passage

through Matter--G. Miffienstedt. (Optik,

Stuttgart, vol. 9, No. 10, pp. 473-480; 1952.)

An account of investigations of the velocity

distribution of electrons after passage through

various gases and solid materials.

537.533.8

705

The Theory of Secondary Emission--J. F.

Marshall. (Phys. Rev., vol. 88, pp. 416-417;

Oct. 1952.) Preliminary note; to be treated in

detail in a forthcoming paper.

538.113/.114

706

Antiferromagnetism--Ochsenfeld. (Z. an-

gew. Phys., vol. 4, pp. 350-360; Sept. 1952.)

A comprehensive review of the subject, with 42

references.

538.3

707

A Simplified Form of the Relativistic Elec-

tromagnetic Equations.--N, W. Taylor. (Aust.

Jour. Sci. Res., Ser. A, vol, 5, pp. 423-429;

Sept. 1952.) Maxwell's equations are expressed

in the form of a single four-vector density

equation, in which the field tensor has only

three distinct complex components. The num-

ber of equations is reduced, but all the usual

classical formulas may be obtained by sepa-

rating the real and imaginary parts.

538.521

708

The Induction of Electric Currents in a

Uniformly Conducting Circular Disk by the

Sudden Creation of Magnetic Poles--A. A.

Ashour. (Quart. Jour. Mech. Appl. Math.,

vol. 5, part 3, pp. 379-384; Sept. 1952.) Using

toroidal coordinates, a Riemann space of two

regions is constructed, as in Sommerfeld's

method of multiform potentials, and the Rie-

mann potential for a single magnetic pole is

determined. Jeans' treatment of uniform finite

plane current sheets is applied to the case of

the circular disk, numerical results being given

for a particular example.

538.56+ 535.14

709

Hertzian Waves and Photons--L. de

Broglie. (Onde élect., vol. 32, pp. 393-396. Oct.

1952.) Discussion of the implications, in physical theory, of an uncertainty relation between

(a) the number of particles of the Bose-

Einstein type associated with a wave and (b)

the phase of that wave.

·

538.566:535.42

710

Diffraction of Electromagnetic Waves by Apertures in Plane Conducting Screens--

J. P. Vasseur. (Ann. Phys. (Paris), vol. 7, pp. 506-563; July/Aug. 1952.) See 2184 of 1952.

538.566:535.42

711

Diffraction by an Edge and by a Corner--

D. S. Jones. (Quart. Jour. Mech. Appl. Math.,

vol. 5, Part 3, pp. 363-378; Sept. 1952.) Con-
ditions are given which are sufficient to ensure
that the current density normal to an edge is
zero at the edge and that there is no line distribution of charge on the edge. An extra con-

dition is given which makes the components of the field parallel to the edge finite. The solution

is then shown to be unique. Simpler conditions are given for two-dimensional fields. The agree-
ment of various known solutions with the conditions here determined is discussed. Certain

simple types of current and charge distribution lead to a unique solution for the diffraction

by corners formed by flat surfaces.

538.566:537.562

712

Propagation of Electric Waves in Stratified

and Continuously Variable Plasmas--W. O.

Schumann. (Z. Naturf., vol. Sa, pp. 612-617;

Nov. 1950.) For aplasma of sandv, ich structure,

with the denser medium inside, there are two

possible frequency ranges for propagation in

which the phase velocity falls from the value

cat the lower limiting frequency to zero at the

upper limiting frequency. When the density

varies linearly towards the interior to an

arbitrarily high value, the wave is strongly

concentrated at the plane for which e=0 and

the phase velocity tends to zero. For a plasma

of uniform density and natural frequency

tos, with outer layers in which density falls off

linearly, propagation is possible only when

w. <wo/2. The more the wave is concentrated

at the region e=.0, and the smaller its phase

velocity, the nearer o.0 approaches to w0/2.

538.632

713

Hall Effect-0. Lindberg. (Paoc. I.R.E.,

vol. 40, pp. 1414-1419; Nov. 1952.) Discussion

of the Hall, Ettingshausen, Nernst, and Righi-

Leduc effects.

539.234:537.311.1

714

Mean Free Paths of Electrons in Evapo-

rated Metal Films--F. W. Reynolds and G. R.

Stilwell. (Phys. Rev., vol. 88, pp. 418-419; Oct. 1952.) Estimates of the mean free paths of

the conduction electrons in Cu and Ag films,

based on resistivity measurements on films of

thickness from 100 to 1500 it, are found to be in good agreement with values calculated from

Dingle's theory (2189 of 1950).

GEOPHYSICAL AND EXTRATERRESTRIAL PHENOMENA

523.746/.75

715

Sunspot Areas, Flares and Filaments ob-

served at the Stockholm Observatory in the

Years 1950 and 1951--Y. Ohman and L. O.

Lodén. (Tellus, vol. 4, pp. 241-248; Aug. 1952.)

523.755:523.78

716

Comparison of Photographs of the Corona

obtained at the Eclipse of 1952, February 25,

with Simultaneous Observations by Lyot

Coronagraphs--H. von Klüber. (Observatory,

vol. 72, pp. 207-209; Oct. 1952.) Photographs of the solar corona taken at Khartoum are

reproduced and discussed in relation to routine

estimates of the intensity of the green corona

line X5303. Possible correlation of particular

features of the corona with geomagnetic effects

is noted.

523.85:621.396.822

717

The Positions of Six Discrete Sources of

Cosmic Radio Radiation--B. Y. Mills. (Aust.

Jour. Sci. Res., Ser. A. vol. 5, pp. 456-463;

Sept. 1952.)

523.854:621.396.822.029.63

718

A Preliminary Survey

1420-Mc/s Line

Emission from Galactic Hydrogen--E. N.

Christiansen and J. V. Hindman. (Aust. Jour.

Sci. Res., Ser. A. vol. 5, pp. 437-455; Sept.

1952.) Report of measurements on a radiation

source having the form of a band of varying

intensity along the galactic equator.

551.510.52

719

The Ionic Equilibrium of the Lower At-

mosphere and Recombination Theories--B.

Vitale. (Ann. Geofis., vol. 5, pp. 257-271; April

1952.)

551.510.535

720

A Note on Ionospheric Wind Measurements

at 150 kc/s--G. H. Millman. (Ann. Géophys.,

vol. 7, pp. 272-274; Oct./Dec. 1951 In English.)

Report of measurements made in Pennsyl-

vania, using a three-receiver technique similar

to that of Mitra (96 of 1950).

551.510.535

721

The Ionization of the E Layer:its Measure-

1953

Abstracts and References

567

ment and Relation to Solar Eruptions--K. Bibi. (Ann. Géophys., vol. 7, pp. 208-214; Oct./Dec. 1951.) Criteria for distinguishing between normal and abnormal layers are discussed. Relatively thin layers are classed as abnormal; their ionization distribution corresponds to a power law with index >2. A definition of foE is given which remains valid for complex layers; foE is the highest critical frequency of a normal layer preceding or coinciding with the first discontinuity between the E and F echoes. Application of this definition to
the evaluation of ionosphere observations made at Freiburg during 1950 and 1951 leads to greater constancy of the daily variations and monthly means of foE. Examination of the values of foE for three summer months indicates
that all deviations >0.2 mc above the monthly mean are attributable to sudden ionospheric
disturbances.

551.510.535: 523.854:621.396.822

722

The Diffraction of Galactic Radio Waves

as a Method of Investigating the Irregular

Structure of the Ionosphere--A. Hewish.

(Proc. Roy. Soc. A, vol. 214, pp. 494-514;

Oct. 1952.) An account of an investigation of

ionospheric characteristics by observation of

changes in the diffraction pattern of radio

waves from the galaxy. Ionospheric irregulari-

ties cause irregular changes of phase in the

galactic waves passing through them. Observa-

tions at two stations about 1km apart indicate

that such ionospheric irregularities may have a

lateral extent of 2-10 km and a variation of

electron density of about 5X 109e/cm7;their

height is about 400 km. they are most pro-

nounced about midnight, and they show little

annual variation. Such portions of the ionosphere

have a wind-like motion with velocities of the

order of 100-300 m/s. The velocity decreases

after midnight, and large velocities are associ-

ated with periods of geomagnetic disturbances.

551.510.535: 546.21-1 :537.56

723

Production of the E-Layer in the Oxygen-

Dissociation Region In the Upper Atmosphere

--D. C. Choudhury. (Phys. Rev., vol. 88, pp.

405-408; Oct. 1952.) The probable value of the

absorption cross section of 02for the ionization

causing the E layer is calculated, using the 02

height-distribution data obtained by Moses and

Wu (129 of 1952). Discussion indicates that

the pre-ionization by solar radiation in the

range 900-1000 A suggested by Nicolet (420

of 1947) and ionization by high-energy photons

emitted from the solar corona [Hoyle and

Bates (388 of 1949)] are both operative in

producing E-layer ionization. The former pro-

duces the normal E layer and the latter is

responsible for the fine structure of the E

layer recently reported by Naismith and

Bramley (473 of 1952).

551.410.535:621.3.087.4

724

A New Ionosphere Sounder--K. Bibl.

(Ann. Géophys., vol. 7, pp. 265-267; Oct./Dec.

1951.) Frequency-sweep apparatus covering

the range 1-16 Mc/s is described. The antenna circuit is eliminated, the high-impedance

rhombic aerial being directly matched to the

power valves. The frequency range is covered in

the other circuits in two wavebands each with a 1:4 ratio; quick waveband changing is

achieved by means of carbon brushes rotating

with the variable capacitors. The transmitter

and receiver have a common oscillator. The

power-supply arrangements are particularly

described; the unit is of small size.

551.510.535:621.087.4

725

Improvements to the Berkner-Wells-Seaton

Type of Ionosphere Sounder--E. Harnisch-

macher. (Ann. Géophys., vol. 7, pp. 262-264;

Oct./Dec. 1951.)

551.510.535:621.317.083.7

726

High-Altitude Research--E. Burgess. (En-

gineer. Load., vol. 194, pp. 338-340 and 370-

373; Sept. 1952.) An account of methods and

equipment used with rockets for investigations at heights up to 250 miles; physical phenomena observed include the ion and electron densities in the inosphere. A description is given of a23-
channel telemetering system transmitting at 1kmc with apeak power of 1kW.

551.510.535: 621.396.11.039.55

727

Ionospheric Measurements at Oblique

Incidence over Eastern Australia--St ioli-

feldt, McNicol and Gipps. (See 807.)

551.594.5:621.396.9

728

Localization of Aurorae with 10-m High

Power Radar Technique, using a Rotating

Antenna--G. Hellgren and J. Meos. (Telas,

vol. 4, pp. 249-261; Aug. 1952.) Radar equip-

ment with apeak pulse power of 100 kW, pulse

width 40 le, and 3-element Vagi aerial rotating

at 2 r.p.m., has been used since May 1951 at

Kiruna Geophysical Observatory for the loca-

tion of aurorae. Preliminary results of the

observations indicate good correlation between

auroral activity, geomagnetic activity, and

the appearance of the Ni layer, a special type

of sporadic-E ionization often appearing in

connection with magnetic bays. The distribu-

tion in range and bearing of the recorded

aurorae agrees with the simple theory that most

·of the radio-wave scattering comes from those points where the radar beam is perpendicular

to the surface of the auroral discharges. The

calculated height distributions of the reflection

centers have maxima around 120 km.

551.594.6: 538.566.029.45/.51

729

Propagation of Very Long Electromagnetic

Waves, and the Wave Spectrum of Lightning

--Schumann. (See 802.)

LOCATION AND AIDS TO NAVIGATION

621.396.9

730

Commercial Radar System--W. F. John-

son. (Eke. Mfg, vol. 47, pp. 72-77; Feb. 1951.)

General description of navigational radar

equipment for merchant ships. Both 3-cm

and 10-cm wavelengths are catered for and a

standard 16-in. television CR-tube provides a

satisfactory display. Accessibility of the vari-

ous units to facilitate maintenance work is a

special feature of the design. The reflectors for

the aerial systems consist of expanded metal

attached to asuitable framework.

621.396.9:621.677.088.22

731

Scanning Aberrations of Radio Lenses--

T. C. Cheston and D. H. Shinn. (Marconi Rev.,

4th Quarter vol. 15, No. 107, pp. 174-184;

1952.)

MATERIALS AND SUBSIDIARY TECHNIQUES

535.215: 546.472.21

732

Photoelectric Measurements on ZnS Single Crystals--J. Krumbiegel. (Naturxvissen-
schaften, vol. 39, p. 447; Oct. 1952.) Measure-

ments on a number of specimens, using monochromatic irradiation of wavelength ranging

from 450 to 2000 mg in steps of 50 mil, indicated two peaks of photoconductivity, at about
750 and 1150 mg respectively. Time lag of
the photocurrent was observed in all cases.

535.215:546.883

733

Photoconduction in Anodic Ta202--L.

Apker and E. A. Taft. (Phys. Rea., vol. 88, pp.

58-59; Oct. 1952.) Observations show that

fundamental optical absorption occurs for

hv>4.6 eV. The resultant photoconduction

between electrolyte and Ta substrate shows a

quantum yield near 0.5 when the field in the

film is of the order of 107 Won.

535.376

734

Light Emission and Destruction of Phos-

phors due to Electron and Ion Impact--W.

Hanle and K. H. Rau. (Z. Phys., vol. 133, pp.

297-308; Sept. 15, 1952.) Measurements were

made of the light emission from ZnS-Ag,

ZniSiOi-Mn and MgW04 phosphors under ex-
citation by Hi, He, Ne, Ar and Xe canal rays. The emission depends only to a very slight ex-
tent on the energy of the ions and is independent of the ion density. With increase of ion mass the emission decreases, with a jump in passing from He to Ne ions. Destruction of the three
phosphors by canal-ray bombardment was found to increase with ion mass and to follow asimple law; it was about 10 times more rapid for ZnS than for the other two phosphors. Organic phosphors were found to undergo deterioration when bombarded by electrons, the effect being correspondingly smaller than in the case of ion bombardment.

537.228.1

735

Voltage Measurements on Rochelle Salt

under Compressive Stress--B. Ptlschel. (Arch.

Lech. Messen., pp. 197-198; Sept. 1952.) A 50-g

weight was dropped from different heighst on

to a Rochelle-salt crystal contained between

brass plates 1mm thick. Voltages up to 600 V

were developed.

537.311.33

736

Electronic States in Crystals under Large

Over-All Perturbations--P. Feuer. (Phys.

Rev., vol. 88, pp. 92-100; Oct. 1952.) Solutions

of the three-dimensional Schr6dinger equation are discussed for a potential which is the sum

of a potential with the periodicity of the

crystal lattice plus a disturbing potential.

General theory developed for large perturba-

tions is applied to aone-dimensional crystal in

a uniform electric field, using the narrow-band

approximation; the probability for an electron

to cross a forbidden energy band is calculated.

The results are considered in relatio nto the

observations of McAfee et al. (164 of 1952) on

Ge p-n junction.

537.311.33

737

On the Electrical Properties of Porous

Semiconductors--E. B. Hensley. (Jour. App!.

Phys., vol. 23, pp. 1122-1129; Oct. 1952.)

Calculations are made of the component of

conductivity due to the presence of an electron

gas in the pores of asemiconductor, such as the

oxide coating of a cathode, on the basis of

simplified pore models. The conditions are

indicated for which this component can become

an appreciable part of the total conductivity.

The thermoelectric power is also investigated.

537.311.33:1546.28+ 546.289

738

Properties of Silicon and Germanium--

E. M. Conwell. (Paoc. I.R.E., vol. 40, pp. 1327-

1337; Nov. 1952.) The latest available informa-

tion on the fundamental properties of Ge and

Si is presented in tables and curves. Electrical

properties, especially carrier density and

mobility, are treated in greatest deaial.

537.311.33:546.289

739

P-N Junctions by Impurity Introduction

through an Intermediate Metal Layer--L. D.

Armstrong. (Paoc. I.R.E., vol. 40, pp.1341-

1342; Nov. 1952.) Indium is melted on to a

gold-plated area on the surface of a Ge n-type

crystal and diffuses into the Ge to form ap-n

junction with a well-defined area.

537.311.33:546.289

740

Lifetime of Injected Carriers in Ger-

manium--D. Navon, R. Bray and H. Y. Fan.

(Paoc. I.R.E., vol. 40, pp. 1342-1347; Nov.

1952.) Carrier lifetime was determined from

measurements of the variation of the conduc-

tance of the test piece after production of

excess carriers by applying a voltage pulse.

The effect of heat treatment was also investi-

gated.

537.311.33: 546.289

741

Measurement of Minority-Carrier Life-

time in Germanium--L. B. Valdes. (Paoc.

I.R.E., vol. 40, pp. 1420-1423; Nov. 1952.)

Equipment is described in which the carriers

are liberated optically on aflat face of acrystal,

568

PROCEEDINGS OF THE I.R.E.

April

their concentration then being measured as a function of distance from the point of liberation.
Lifetimes from afew to several hundred microseconds can be determined.

537.311.33:546.289

742

Activation Energy of Heat-Treatment-

Introduced Lattice Defects in Germanium--

R. M. Baum and C. S. Hung. (Phys. Rev.,

vol. 88, pp. 134-135; Oct. 1952.) Hall-coeffi-

cient and resistivity measurements are reported

on two single crystal samples converted from

n-type to p-type by heat treatment. The values

deduced for the thermally produced acceptors,

viz. 0.058 and 0.047 eV respectively, are con-

siderably higher than for chemically produced

acceptors; this result is in general agreement

with that of Dunlap (Phys. Rev., 1st July

1952, Vol. 87, No. 1, p. 190.)

537.311.33: 546.289

743

p-n Junctions produced by Growth-Rate

Variation--R. N. Hall. (Phys. Rev., vol. 88,

p. 139; Oct. 1952.) More than 100 uniformly

spaced p-n junctions have been formed in an

ingot of Ge by periodically varying the rate of

growth of the crystal from the melt. The proc-

ess depends on the presence in the melt of two

impurities of opposite type, cg Sb (n type) and

Ga or In (p type), whose segregation constants

vary at different rates with rate of growth.

537.311.33:546.289:548.55

744

Preparation of Germanium Single Crystals

--L. Roth and W. E. Taylor. (Pxoc. I.R.E.,

vol. 40, pp. 1338-1341; Nov. 1952.) Descrip-

tion of two methods, using a vacuum furnace

with HF induction heating. In the first method

the crystal is grown in the crucible by control-

ling the rate of cooling; in the second, a seed

crystal is gradually withdrawn from the sur-

face of the melt.

537.311.33:621.314.632

745

Cadmium-Sulfide Crystal Rectifiers--(Elec-

Ironic; vol. 25, pp. 189, 192; Dec. 1952.)

Long hexagonal n-type CdS crystals were

tested for rectifier properties; the influence of

orientation, mounting, and impurities was

investigated. Point-contact rectifiers were

obtained, optimum rectification occurring at

7 V. Transistor action was not obtained, but

is thought to be possible.

537.311.33:621.314.7

746

Transistor Electronics: Imperfections, Uni-

polar and Analog Transistors--W. Shockley.

(PRoc. I.R.E., vol. 40, pp. 1289-1313; Nov.

1052.) A detailed discussion of the physics of

transistors, particularly as regards the proper-

ties of holes and electrons and the effects of

impurities, together with a description of

transistor action and of anew class of unipolar

transistors, some of which, from their similarity

to tubes, are termed analogue transistors.

537.311.33: 621.396.822

747

Current Noise in Semiconductors. A Re-

examination of Bernamont's Data--D. A.

Bell. (Phil. Meg., vol. 43, pp. 1017-1111;

Oct. 1952.) The results obtained by Bernamont

(1715 of 1937) on thin metal films, here re-

garded as semiconductors, indicated that cur-

rent noise varied approximately inversely with

frequency over the range 96 cps-162 kc. On

adjusting his results to make allowance for

Johnson noise and for the supposed loss of a

factor of 10 in the calculations, the noise from

his resistor aft" closely follows the inverse-

frequency law for all current densities.

537.311.33: 621.396.822

748

Current Noise in Semiconductors--D. A.

Bell. (Wireless Eng., vol 30, pp. 23-24; Jan.

1953.) Discussion of the law relating the fre-

quency spectrum of the noise voltage with the

current in a semiconductor.

538.114

749

Magnetic Domains--H. J. Williams. (Bell

Lab. Rec., vol. 30, pp. 385-396; Oct. 1952.)
The domain structure of magnetic materials is shown by numerous microphotographs and
diagrams, and electron-spin changes and domain-boundary movement under the action of
amagnetic field are illustrated by diagrams and models.

538.221

750

Applications and Properties of Ferroxcube

--(Electronic Appl. Bull., vol. 13, pp. 44-58;

March/April 1952.) Tables and numerous

curves are given which show the properties and

operating characteristics of the various available types and grades of ferroxcube, so that the

material most suitable for a particular applica-

tion can easily be selected.

538.221

751

Ferromagnetic Properties of Hexagonal Iron-Oxide Compounds with and without a

Preferred Orientation--G. W. Rathenau, J.

Smit and A. L. Stuyts. (Z. Phys., vol. 133, pp.

250-260; Sept. 15, 1952, In English.) An

account of ferroxdure, a ceramic material

with the composition Ba0.6Fes0s, has previ-

ously been given [2824 of 1952 (Went et al.)].

Materials of about this composition are here

discussed. The variation of the magnetization

with the strength of the applied field is shown

graphically. The formation of Bloch walls

results in irregularities in the crystal structure.

With regular crystal distribution and crystals

above a certain critical size, demagnetization

by Bloch-wall displacement can occur for

positive field strengths of about 4X I., where I.

is the saturation magnetization. When crystal-

orientation processes are applied to ferroxdure

materials, BH... values of 3X 108gauss.oersted can be reached. An improvement of the texture

of these ceramics is obtained by increase of

grain size.

538.221

752

A New Method of Melting Ferromagnetic

Semiconductors. BaFei8027, a New Kind of

Ferromagnetic Crystal with High Crystal

Anisotropy--H. P. J. Wijn. (Nature (London),

vol. 170, pp. 707-708; Oct. 1952.) An account is

given of the HF method used in melting a

mixture of Fes0. and BaCO3 in an atmosphere

of Ns; an alumina crucible was used, with a lid of Rh or Ir to give additional surface heat-

ing. From one melt acrystal with the composi-

tion BaFen0s7 was obtained. This has astructure resembling that of BaFentOue [2824 of 1952

(Went et al.)] and exhibits very high crystal

anisotropy.

538.221:548.0

753

Coercive Force and Crystal Energy--W.

Gerlach. (Z. Phys., vol. 133, pp. 286-290;

Sept. 15, 1952.) Sintered Ni rods show an

increase of coercive force with decreasing tem-

perature proportional to the square root of the crystal energy. Wires of solid Ni annealed for

a long time at a moderate temperature show a

similar effect, but sintered Fe and Co rods

exhibit anomalous effects.

538.221:548.1.023

754

Crystal Structure of BaFeuGsr--P. B.

Braun. (Nature (London) vol. 170, p. 708;

Oct. 25, 1952.) Results are tabulated of an

X-ray investigation of the crystal mentioned

by Wijn (752 above).

538.221:621.392.26

755

Magnetic Double Refraction at Microwave

Frequencies--M. T. Weiss and A. G. Fox.

(Phys. Rev., vol. 88, pp. 146-147; Oct. 1952.) Magnetic double refraction has been observed

at 24 and 9 lane, evidenced by a conversion from linear to elliptical polarization of adomi-

nant TE wave in a circular waveguide filled

with ferrite and subjected to a dc magnetic field transverse to the direction of propagation

and at 45° to the initial direction of polariza-

tion. The double refraction is attributed to the

difference between the RF permeability parallel to and transverse to the field.

538.23

756

A Relation between Hysteresis CoefflcieLt

and Permeability--M. Kornetzki. (Z. angew.

Phys., vol. 4, pp. 343-345; Sept. 1952.) As-

suming for simplicity that the magnetization

curves of various materials, measured in closed

magnetic circuits, are distinguished from one

another only by different scale factors, it is

shown that the relative hysteresis coefficient

is proportional to the initial permeability

and inversely proportional to the saturation

induction. Measurements on Ni-Zn ferrites with initial permeabilities of 30-1500 indicate

hysteresis coefficients differing among them-

selves by a factor of 50, though the ratio of

hysteresis coefficient to initial permeability varies only by a factor of 3.

538.242

757

A New Gyromagnetic Effect in Permalloy and Iron--S. J. Barnett and L. A. Giambomi.

(Phys. Rev., vol. 88, pp. 28-37; Oct. 1, 1952.) Experiments were made with long cylinders of

compressed powder material magnetized axially nearly to saturation and subjected to a weak

transverse alternating magnetic field of period

much greater than the relaxation time. A trans-

verse magnetization was observed perpendicu-

lar to the applied alternating field. Measured values of the effect are in substantial agree-

ment with results of earlier experiments.

539.234

758

The Contamination in Evaporated Films by

the Material of the Source--O. S. Heavens.

(Proc. Phys. Soc., vol. 65, pp. 788-793; Oct.

1952.) A microchemical and a radioactive-

tracer method were used to investigate con-

tamination of Ag and Ge films by the boats or

filaments used in the vaporization process.

One or two parts of W or Mo in 108 can be

detected by the tracer method. Minimum

contamination attainable was of the order of a few parts in 108.

546.431.824- 31:539.11

759

Domain Properties in BaTiO3--W. J. Merz.

(Phys. Rev., vol. 88, pp. 421-422; Oct. 1952.) Short account of investigations of the arrangements and movements of the ferroelectric

domains in single crystals of BaTiOs under
the influence of an electric field. Only so-called 90° walls have hitherto been reported, but the

smaller 180° walls constituting the true domain

boundaries have now been observed. The average width of these antiparallel domains, as

measured by means of a microscope, is from

0.1 µ to about 10 p. Observations were made of domain movements corresponding to each

step of ahysteresis loop. More detailed studies

of the number of domains, their velocities and

relaxation times, are being made by applying very short rectangular electrical pulses.

621.3.042.143:538.221

760

Ultrathin Magnetic Alloy Tapes with Rectangular Hysteresis Loops--M. F. Littmann. (Elec. Eng., N.Y., vol. 71, pp. 792-795; Sept. 1952.) Text of paper presented at A.I.E.E

General Meeting, June 1952. Report of an experimental study of high-permeability and
high-resistivity tapes, suitable for cores for

hf applications. Thicknesses range from *to 1 mil.

621.314.2.042.143

761

Core Materials for Small Transformers--

C. C. Horstman. (Tele-Tech, vol. 11, pp. 40-42, 90; Oct. 1952.) Discussion of the reduction in

transformer weight and electrical losses effected

by the use of hypersil cores produced from

strip material of thickness 1-5 mil. A recent development is the forming of longitudinal

grooves in the thin strip prior to winding into

a core. This results in increased rigidity and

higher stability under temperature cycles.

Improvements in Ni-alloy materials are also

1953

Abstracts and References

569

noted, such as the production of strip materials of thickness only 1mil, with retention of high permeability and low coercive force.

621.318.1.042.15

762

The Production and Application of Magnetic

Powders--G. R. Polgreen. (G. E.G. J., vol. 19,

pp. 152-169; July 1952.) A description is given

of modern methods and equipment for the

manufacture of Fe and Cu-Ni-Fe-alloy (Gecal-

boy III) powders; the chemical methods used

result in reduced losses and improved stability.

The properties of these powders and of the

resulting cores are compared with correspond-

ing properties of commercially available sheet

materials and ferrites.

MATHEMATICS

517.511

763

The Decomposition of Functions--J. W.

Head. (Proc. Comb. Phil. Soc., vol. 48, part 4,

pp. 742-743; Oct. 1952.) Discussion of func-

tions of the step-voltage type. If fin approaches

asymptotically the value In e when the time

scale is suitably chosen, f(I) can be decomposed

into a series of Laguerre functions which are

mutually orthogonal over the range 0- co. The

coefficients in this series are here obtained in

terms of the various Laguerre functions and

of f(I) and dL,,(01d1 when the Laguerre func-

tion L.(t) has a zero. An explicit formula is

derived involving functions which can be calcu-

lated and tabulated.

517.942.82

764

General Rules for Laplace Transformation

U. Kirschner. (Funk u. Ton, vol. 6, pp. 541-

547; Oct. 1952.) A statement of general rela-

tions applying in different mathematical opera-

tions.

681.142

765

MONECA--A New Network Calculator for

Motor Performance Calculations--C. G. Vei-

nott. (Elec. Eng. N.Y., vol. 71, pp. 795- .,01;

Sept. 1952.) Text of paper presented at

A.I.E.E. General Meeting, January 1952.

Description of an analogue computer for calcu-

lations on single-phase induction motors.

681.142:621.314.7

766

An Optical Position Encoder and Digit

Register--H. G. Follingstad, J. N. Shive and

R. E. Yaeger. (Paoc. I.R.E., vol. 40, pp. 1573-

1583; Nov. 1952.) Transistor circuits are used

in a small unit which performs the operations

of 6-digit photoelectric encoding, pulse regeneration, digit storage, reflected-to-natural binary

translation, and digit shifting.

681.142:621.314.7

767

A Transistor Shift Register and Serial

Adder--J. R. Harris. (Pctoc. I. R.E. vo.. 40,

pp. 1597-1602; Nov. 1952.) Equipment is

described which can store a pair of binary

numbers, add them, and produce the sum a

digit at a time. The equipment is constructed

from primary transistor units including a flip-

flop circuit, pulse amplifiers with and without

delay, and diode gate circuits.

681.142: 621.395.625.3

768

On Two Problems in Potential Theory and

their Application to the Design of Magnetic

Recording Heads for Digital Computers--A. D.

Booth. (Brit. Jour. Appl. Phys., vol. 3, pp.

307-308; Oct. 1952.) Both theory and experi-

ment indicate that the field outside the gap

depends very little on the particular shape of

pole-piece.

681.142:621.396.645:621.314.7

769

Regenerative Amplifier for Digital Computer Applications--J. H. Felker. (Paoc. I.R.E.

vol. 40, pp. 1584-1596; Nov. 1952.) An ampli-

fier using a point-contact transistor is used to

regenerate digital information at a rate of 104

/sec and to develop pulses with rise times

<0.05 µs.

MEASUREMENTS AND TEST GEAR

531.76

770

A Combined Timer and Cycle Counter--

P. Huggins. (Electronic Eng., vol. 24, pp. 578-

579; Dec. 1952.) Description, with full circuit

details, of a unit which combines the functions

of timer and cycle counter (2841 of 1952)

within the range 0.02-2.64 sec. Two 12-

position delcatron tubes are used which pro-

vide visual indication of the time, in steps of

1/50 sec, as the apparatus operates. Conversion from timer to cycle counter is effected by a

simple switch.

531.76:621.318.57:621.317.755

771

A Dekatron C.R.O. Time Marker--J. H. L.

McAuslan. (Electroinc Eng., vol. 24, pp. 567-

569; Dec. 1952.) Description, with detailed

circuit diagram, of equipment using Type-

GclOB dekatrons to provide longer time-

markers on the screen of a cro at each tenth

pulse, with additional negative markers for

each hundredth pulse.

621.316.8(083.74)

772

Gold-Chromium Standard Resistors--A.

Schulze and H. Eicke. (Z. angew. Phys., vol. 4, pp. 321-324; Sept. 1952.) Experiments during

the last 15 years have shown standard resistors

made of Au-Cr alloy to be superior to those

made of manganin. New constructions are de-

scribed in which the resistance coil is housed

in an argon-filled glass envelope; these types

are suitable for measurements of the greatest

precision, and are designated principal stand-

ard resistors.

621.317.328.089.6

773

Calibration of Commercial Field-Strength

Meters--C. C. Cook. (Tele-Tech, vol. 11, pp.

44-46. 99; Oct. 1952.) An account of the serv-

ice provided by the National Bureau of

Standards, with an outline of the methods of

calibration of meters operating in the ranges

10 kc-30 mc and 30-300 mc.

621.317.336.029.64

774

The Determination of Impedance with a

Double-Slug Transformer--R. C. Ellenwood

and E. H. Hurlburt. (Paoc. I.R.E., vol. 40,

pp. 1690-1693; Dec. 1952.) Formulae are de-

rived by means of which the required impe-

dance can be determined from a knowledge of

the length, spacing, position and «effective

dielectric constant of the slugs. A method of

determining the «effective dielectric constant

experimentally is described. Results of accuracy

comparable with those given by a precision

slotted-line method have been obtained.

621.317.337:621.396.611.1

775

Q-Factor Measurements--A. G. Wray

(Marconi Instrumentation, vol. 3, pp. 118-123;

Oct. 1952.) The Q factors of single reactive

components and of complete oscillatory cir-

cuits are discussed. The principles of measurement methods are outlined, and resistive,

inductive and capacitive methods of injecting

the necessary small test emf are considered.

621.317.351:534.442.2

776

Audio-Frequency Spectrum Analysis--W.

Sagajiblo: S. V. Soanes. (Electronic Eng.,

vol. 24, p. 581; Dec. 1952.) Comment on 3171

of 1952 and author's reply.

621.317.352:621.395

777

Reference-Level Test Equipment with

Direct Indication, and its Importance for the

Improvement of Telephony--K. Braun and

H. Koschel. (Ferntneldetech. Z., vol. 5, pp. 447-

455; Oct. 1952.) Description of apparatus,

including artificial mouth and artificial ear,

suitable for tests on complete telephone cir-

cuits or on individual items of equipment.

621.317.7.029.6:621.396.615.141.2

778

Microwave Devices for Magnetron Pro-

duction Testing--M. Nowogrodzki. (Tele-

Tech, vol. 11, pp. 36-37, 111; Oct. 1952.)

Outline description of (a) a cavity-resonator
type of wavemeter using aneon lamp for visual indication of resonance, (b) equipment for measurement of output power, using a water load, (c) a rf power monitor for use in life tests.

621.317.7.029.62/.63:621.392

779

Helical Measuring Line for Microwaves--

F. Tischer. (Z. angew. Phys., vol. 4, pp. 345-

350; Sept. 1952.) A line of considerably reduced

length and of characteristic impedance 50

it comprises a helical conductor wound in a

groove in an insulating sleeve on an axial

conductor, the whole being enclosed in a

coaxial tube with aslot through which projects

as inductive probe of a type previously described (3048 of 1951). When the parameters

are correctly chosen, phase and amplitude fluctuations along the line are <1% over the

frequency range 250 mc-2 kmc. The accuracy

of measurements made with this line is equal

to that with a medium-quality straight line.

621.317.725.088.22:621.385.2

780

Diode Tube-Voltmeter Errors--G. D.

Morgan. (Electronic Eng., vol. 24, pp. 575-577;

Dec. 1952.) Discussion based on experience

with a voltmeter using a Type-VR78 (Mazda-

D.1) diode, of the magnitude of the possible

errors in diode voltmeters.

621.317.733:621.317.374

781

New Method for the Measurement of

Dielectric Loss Angle--L. Schnell (Elektro-

iechnika, Budapest, vol. 45, pp. 264-268. Dis-

cussion, pp. 268-269; Sept. 1952.) A bridge

arrangement is described in which the voltage

across the meter diagonal is a nearly linear

function of tan 8.

621.317.733.029.51/.63:621.317.335

782

A Measurement Bridge for 0.1-1000 Mc/s

--H. Voigt. (Arch. elekt. übertragung, vol. 6,

pp. 414-418; Oct. 1952.) The four capacitors constituting the arms of the bridge are formed by a set of parallel disks within a cylindrical

screen. A flat test sample of a material whose dielectric properties are to be determined is

introduced between one end plate and the removable end of the screen. The other end

plate has a micrometer adjustment for balancing the bridge. A rectifier and tube volt-

meter serve as balance indicator. A cylindrical type of construction is also shown that is

suitable for measurements on liquid dielectrics.

Typical results for the variation of dialectric

constant and loss angle of PVC with the amount of softening agent and with frequency

are shown in diagrams.

621.317.737.088.22:621.3.012.3

783

Q-Meter Correction Chart for Q-Voltmeter

Loading--R. Lafferty. (Tele-Tech, vol. 11, p.

43; Oct. 1952.) An abac is given for correcting

errors due to the shunting effect of the input

resistance of the tube voltmeter used in the

measurements.

621.317.755:621.314.7.012

784

Oscilloscopic Display of Transistor Static

Electrical Characteristics--N. Golden and R.

Nielsen. (Paoc. I.R.E., vol. 40, pp. 1437-1439; Nov. 1952.) Description, with schematic cir-

cuit diagram, of cro equipment permitting

rapid comparison with a standard.

621.317.755:621.396.6

785

Slow-Speed Circular Timebase--(See 673.)

621.317.78.029.6

786

ALaboratory Power Meter--E. F. Schelisch.

(Marconi Rev., vol. 15, pp. 167-173; 4th

Quarter 1952.) Two cartridge-type Si-crystal

diodes are connected as shunt elements Xo/4

apart in acoaxial line, a matching transformer

being fixed between them. Power measurement

to within 0.1 db is achieved over a range of

40 db or more in the microwave band. Possible

uses of the device as a FM discriminator, an

570

PROCEEDINGS OF THE I.R.E.

April

a.m. demodulator, or a frequency multiplier, are illustrated and discussed.

621.396.645.35

787

A High-Sensitivity Direct-Voltage Ampli-

fier with High Input Resistance--W. Kroebel.

(Z. Phys., vol. 133, pp. 30-40; Sept. 1952.) A

new type of contact breaker is described which

uses a flexural type of double quartz plate as

its vibrator. A type of construction is used in

which the contact gap is completely screened

from the exciting voltage applied to the crystal.

Application is made to the amplification of

direct voltages from sources of very high in-

ternal resistance. Full circuit details of an

amplifier are given with which, for a band-

width of 1 c/s and input resistance of 100

Mil, apower of about 5X 10-,0 W can be meas-

ured.

621.396.822.029.64:621.327.3

788

The Design of Microwave-Noise Genera-

tors--P. M. Ratcliffe. (Marconi Instrumenta-

tion, vol. 3, pp. 124-127; Oct. 1952.) Mumford

(929 of 1950) showed that an ordinary Hg-

vapor discharge lamp mounted in a wave-

guide acts as a good noise source for the 6-cm

band. Similar sources have now been produced

for the Sand X bands at 10 cm and 3.2 cm. The

new tubes are about 9 in. long and 1 in. in

diameter, and are filled with a Hg-vapor and

Ar mixture at a pressure of 30 mm Hg, the

dc power consumption for reliable operation

being about 10 W. A filament is fitted at each

end, one being heated by ac to assist in starting

the discharge. Matching of the source to the

waveguide is effected for the X-band mounting

by insertion of the tube in the E plane of the

waveguide at an angle of 10° to the waveguide

axis. For the S-band mounting an H-plane

fitting is used with the tube at right angles to

the narrow walls of the waveguide. The genera-

tors deliver a noise-power output about 15 db

above zero level.

OTHER APPLICATIONS OF RADIO AND ELECTRONICS

53.087.55:771.4

789

Photographic-Exposure Timers providing

Compensation for Supply-Voltage Variations--

R. J. Hercock and D. M. Neale. (Paoc. I.R.E.,

vol. 99, pp. 507-515; Part II, Oct. 1952.) De-

scription of a circuit giving exposure times, at

the nominal supply voltage, continuously adjustable from 1sec to 1min or more, with an

intensity-time product constant to within

±5% for supply-voltage variations from

+15% to --20%.

534.1.08

790

Vibration Measurements--R. Winslade.

(Electronic Eng., vol. 24, pp. 553-557; Dec.

1952.) Description of a pickup unit, with

spring-supported coil moving in a magnetic

field, for measuring vibration amplitudes,

velocities and accelerations.

621.315.3.001.41

791

Continuous Measurement of Cable Diam-

eters--E. C. R. Scarfe. (Elect. Times, vol. 122,

pp. 399-401; Sept. 1952.) The extruded cable

runs between apivoted tungsten-carbide stylus

and a rotating anvil. Movement of the stylus

varies the air gap between a fixed quartz

crystal and one of its electrodes. The frequency

variations derived from the capacitance change

modulate a 100-kc carrier. The direct voltage

obtained via conventional discriminator and

output circuits is applied to a meter, cali-

brated in thousandths of an inch, which shows

deviations from a preset nominal diameter.

621.316.7:621.314.7

792

Control Applications of the Transistor--

E. F. W. Alexanderson. (Paoc. I.R.E., vol. 40,

pp. 1508-1511; Nov. 1952.) The possibility is

examined of using transistors for control func-

tions at present performed by magnetic ampli-

fiers, amplidynes and thyratrons. A transistor

controlled by auxiliary transistors can function

in amanner similar to that of aphase-controlled rectifier, and has certain definite advantages.

621.317.083.7:551.510.535 High-Altitude Research--Burgess.
726.)

793 (See

621.384.6:621.317.083.7

794

A Telemetering System for aLarge Electro-

static Accelerator--C. W. Johnstone, J. F.

Kalbach and H. J. Lang. (Paoc. I.R.E., vol.

40, pp. 1664-1674; Dec. 1952.) Description of the 16-channel pulsed-light-beam system used

for monitoring and controlling the ion source,

focusing and belt charging in the 12-MeV es

accelerator nearing completion at Los Alamos.

621.385.833

795

Electron-Optical Properties of Electrostatic

Lenses--W. Lippert and W. Pohlit.

Stuttgart, vol. 9, no. 10, pp. 456-462; 1952.)

Results of experimental investigations are pre-

sented as families of curves from which the

electron-optical properties of an e.s. lens of the

symmetrical 3-electrode type can be deter-

mined from the parameters of the electrode

system.

621.387.4

796

Self-Quenching Parallel-Plate Vapour-

Filled Counters with Operating Voltages below

the Static Breakdown Field Strength--J.

Christiansen. (Z. angew. Phys., vol. 4, pp. 326-

329; Sept. 1952.)

621.397.424

797

Geiger Counter Tubes--N. B. Balaam.

(Electronic Eng., vol. 24, pp. 558-561; Dec.

1952.) Description of the construction and

characteristics of a series of counter tubes for

various specific purposes. All are of the cylin-

drical gas-filled type, with halogen or organic

quenching agent.

621.387.424: 537.525.92

798

Remark on the Space-Charge Sheath of the

Geiger Counter--D. H. Wilkinson. (Rev. Sci.

¡asir., vol. 23, pp. 463-464; Sept. 1952.) The

popular notion of the Geiger-counter space-

charge sheath as a thin expanding shell re-

quires modification. Owing to the considerable

charge transported in the sheath, it grows in

thickness as it crosses to the cathode and may

occupy more than half the total volume of the

counter. The attendant wide spread in arrival

time of the positive ions at the cathode may

explain, to some degree, the time distribution

of spurious counts.

621.387.424:539.26

799

A [Geiger-Miilled Counter Arrangement

for X-Ray Interference Measurements--R.

Berthold and A. Trost. (Schweiz. Arch. angew.

Wiss. Tech., vol. 18, pp. 277-282; Sept. 1952.)

621.791.3: 534.321.9

800

Ultrasonic Tinning Techniques for Alumi-

num--A. E. Crawford. (Electronics, vol. 25,

pp. 102-105; Dec. 1952.) The ultrasonic iron

described uses a self-driving longitudinally ex-

cited magnetostriction element made of Co-Fe

alloy laminations and operated as aX/2 resona-

tor. The frequency is about 20 kc. A proposed

plant for continuous tinning of Al wire is also

described.

621.791.3: 534.321.9

801

Ultrasonic Tinning of Aluminum--P. Wenk

and H. Boljahn. (Z. Metallkde, vol. 43, pp.

322-324; Sept. 1952.) Description of an ultra-

sonic soldering tool using a 20-kc Ni magneto-

striction oscillator, with illustrations of tests on

sheet Al, using pure Sn as solder.

PROPAGATION OF WAVES

538.566.029.45/.51:551.594.6

802

Propagation of Very Long Electromagnetic

Waves, and the Wave Spectrum of Lightning--

W. O. Schumann. (Naturwiss., vol. 39, pp.

475-476; Oct. 1952.) Regarding lightning as a

Dirac current pulse, a formula derived for the

wavelength of maximum intensity (X,,,) shows that X,,, increases as the square of the distance
from the point where the flash occurs. The im-
pulse received at a distance from the flash is the Fourier integral of the spectral components of the wave, a formula for which is given. The
actual pulse shape for a lightning flash prob-
ably favors the lower frequencies in the spectrum. A detailed account of the investigation is to be published in Z. angew. Phys.

538.566.2

803

A Method of Solving the Wave Equation in

a Region of Rapidly Varying Complex Refrac-

tive Index--J. J. Gibbons and R. L. Schrag.

(J. Appl. Phys., vol. 23, pp. 1139-1142; Oct.

1952.) The equation for wave propagation in

an ionized medium is transformed into an

integro-differential equation with only one real

dependent variable, thus avoiding the need to

solve two simultaneous differential equations.

The solution yields one of the two wave func-

tions directly, the second being derived from

the first by direct integration. The method is

illustrated by computing the reflection co-

efficient for aregion where the refractive index

passes through asharp peak.

621.396.11

804

Scattering of Electromagnetic Energy in a

Randomly Inhomogeneous Atmosphere--H.

Staras (Jour. Appl. Phys., vol. 23, pp. 1152-

1156; Oct. 1952.) First-order perturbation the-

ory is used to derive an integral representing

the scattered power at areceiver resulting from

random inhomogeneities in the propagating

medium. The expression obtained corresponds

with that used by Booker and Gordon (1757 of

1950), but instead of the space-correlation

function of refractive index used by them a

time-correlation function is introduced which

permits evaluation of the time average of the

scattered power; this time-correlation function

is directly measurable. For small-scale turbu-

lence the average scattered power is not

affected by the particular model of atmospheric

turbulence chosen; for large-scale turbulence

the results depend on the particular time-

correlation function chosen and on particular

assumptions regarding the scattering bodies.

621.396.11

805

Effect of Magnetic Field in Oblique Propa-

gation over Equatorial Region--B. Chatterjee.

(Indian J. Phys., vol. 26, pp. 297-312; June

1952.) Curves of the Booker type (422 of 1939)

are presented for the case of propagation across

an equatorial region, and the phenomenon of

lateral deviation is discussed. Propagation

curves are also given for the particular trans-

mission paths Calcutta-Bandoeng and Cal-

cutta-Bombay. The calculations were made

for the case of a flat stratified layer over aflat

earth, so that correction factors are required to

take account of the earth's curvature.

621.396.11.029.51:551.510.535

805

The Polarization of Vertically Incident

Long Radio Waves--J. M. Kelso, H. J. Near-

hoof, R. J. Nertney and A. H. Waynick. (Ann.

Géophys., vol. 7, pp. 215-244; Oct./Dec. 1951,

In English.) Analytical expressions relating the

distribution of electron concentration and col-

lision frequency in the ionosphere to the

polarization characteristics are derived, the

wave being treated as a single magneto-ionic

component. Measurements made on afrequency

of 150-kc are reported and interpreted. A model

of the D and E layers is assumed which gives

theoretical results in good agreement with ex-

perimental observations. See also 517 of Feb-

ruary (Gibbons and Nertney).

-

621.396.11.029.55: 551.510.535

807

Ionospheric Measurements at Oblique In-

cidence over Eastern Australia--M. Stroh-

feldt, R. W. E. McNicol and G. de V. Gipps.

(Aust. Jour. Sel. Res., Ser., vol. 5, pp. 464-472;

Sept. 1952.) An account of attempts made to

identify night-time ionosphere reflecting layers

1953

Abstracts and References

571

by measuring apparent path lengths of pulsed
transmissions on 5.8 mc over a baseline of 763 km, using responder technique. The characteristics of beacon triggering are discussed in

for the ranges 3.3-10 mc and 8.8-30 mc. A
single Type-DK92 heptode is used; this is a 50-mA miniature heptode with a variable-s characteristic making it suitable for agc.

spectral-density and correlation functions and a criterion of network efficiency based on distortion. The statistical method is applied to the optimum noise filter of Wiener.

relation to the type of echo received. Correlation was established between occurrences of E, observed at oblique incidence and at vertical
incidence near the mid-point of the trajectory. Unusual records of Pedersen rays are shown,
and sudden height increases and diffuseness of F2 echoes are discussed. A check on the obliqueincidence theory, using a Millington transmission curve in conjunction with verticalincidence h'f records, yielded resonable agreement between measured and deduced reflec-
tion heights. A rough analysis of obliqueincidence pentrations showed that the average frequency separation of the ordinary-ray and
the extraordinary-ray m.u.f. was about half
the gyromagnetic frequency.

621.396.81

808

A Comparison of C.W. Field Intensity and

Backscatter Delay--W. L. Hartsfield and R.

Silberstein. (PRoc. I.R.E., vol. 40, pp. 1700-

1706; Dec. 1952.) The relation between back-

scatter and skip phenomena was investigated by comparing the intensity of the 15-mc

WWV signals, received at White Sands in New

Mexico, with the recorded delay times for the

back-scatter received at Sterling, Virginia,

from a pulse transmitter operating at about

the same frequency. Rapid variations in the back-scatter records for disturbed days corre-

spond in order of magnitude with previously

observed motions of ionosphere irregularities.

621.396.81.029.62

809

Field Strengths Recorded on Adjacent

F.M. Channels at 93 Mcis over Distances from 40 to 150 Miles--G. S. Wickizer and

A. M. Braaten. (PRoc. .R.E., vol. 40, pp.

1694-1699; Dec. 1952.) Analysis of records of

the field strength received from stations

KE2XCC (93.1 mc, Alpine, N. J.) and WBZ-

FM (92.9 mc, Boston, Mass.) over a period of more than a year at two places on Long

stand. For the evening hours there is a sea-

sonal trend towards higher intensities in sum-

mer. The over-all variations were larger for the

longer transmission paths. The hourly distribution curves are discussed in relation to

possible modes of propagation.

621.396.621.54: 621.396.82

814

Microphony in Superhet Oscillators--H. Stibbé. (Wireless World, vol. 58, pp. 504-506;

vol. 59, pp. 35-38; Dec. 1952 and Jan. 1953.)

Microphony in the oscillators of superheterodyne receivers is caused by a frequency-

discriminator action of the IF amplifier plus

detector when the tuning is not quite cor-

rect. It can be prevented in some circumstances by using an over-critically coupled IF am-

plifier, thus permitting a greater degree of de-

tuning before the discriminator action starts. A numerical calculation is made of the effect of vibration of tuning-capacitor plates for a

typical case; the figures indicate that the highest possible degree of rigidity and sym-

metry are required in the assembly of this com-

ponent. Methods are described for mounting it with good mechanical insulation. Measure-

ments of the microphony-free output of a

receiver are also described.

621.396.822:621.396.62

815

Noise in Receivers and Amplifiers--S.

Gratama. (Tijdschr. ned. Radiogenoot., vol. 17,

pp. 207-247; Sept./Nov. 1952.) The various causes of noise in receivers are surveyed. The

physical mechanisms of shot effect, induced

grid noise and total-emission noise in valves

are explained. Practical use can be made of the correlation which exists between induced

grid noise and shot effect to reduce the noise

caused by the latter. 59 references.

621.396.822:621.396.621

816

A Note on the Approach of Narrow-Band

Noise after a Nonlinear Device to a Normal

Probability Density--G. R. Arthur. (Jour.

Appl. Phys., vol. 23, pp. 1143-1144; Oct. 1952.) From the integral equation derived by Kac and

Siegert (3645 of 1947) for the output of alowpass filter preceded by a nonlinear device excited by anoise source, the first three central
moments of the probability density of the output signal are obtained and the approach of these moments to those of a Gaussian density

is demonstrated.

621.396.822.029.62

817

621.395.521.3:621.396.97

820

A Variable Equalizer for Broadcast-Pro-

gramme Circuits on Trunk Lines--C. M. Hall. (Telecommun. Jour. (Australia), vol. 8, pp.

311-313; Oct. 1951.) Description of equipment

designed to facilitate the work involved in equalizing trunk routes in Queensland, where

several circuits are over 800 miles in length and

two exceed 1000 miles. The equalizer finally

adopted includes three units, one for correction of the low-frequency slope of the response curve, the next for the response hump usually

occurring at about 150 c/s, and the last section

for the high-frequency response. Plug-in attenuation pads are provided so that any

reasonable degree of equalization can be ob-

tained in each section.

621.396.333+621.396.51: 621 .396.71

821

Navy V.L.F. Transmitter will radiate 1000

kW.--T. D. Hobart. (Electronics, vol. 25, pp.

98-101; Dec. 1952.) Description of transmitter

sited at Jim Creek Valley, near Arlington,

Washington, and planned to provide both cw

and frequency-shift teleprinter communica-

tion with ships throughout the Pacific area,

including submerged submarines. The twin

500-kW power amplifiers use a push-pull ar-

rangement of Type-5831 water-cooled triodes,

with 6-V thoriated tungsten filaments taking

about 13 kW of heating power, and 11.5 kV

anode voltage; each amplifier feeds half of the

aerial. The tuning range is 14.5-35 kc. The

aerial is suspended between two 3000-ft moun-

tain ridges, and comprises a horizontal zig-zag

of ten spans, arranged in two groups of five,

with a 900-ft down-lead at the mid-point of

each span. Facilities for a 46-man staff are

provided on the 7000-acre site.

621.396.4

822

A Beam Radio System with Pulse-Phase

Modulation for 12- and 24-channel Telephony

Transmission--E. Hazier and H. Holzwarth;

H. Holzwarth and W. Arens; E. Schulz, G.

Piefke and E. Seibt; W. Wild, U.v. Kienlin and

H. Simon. (Fernmeldetech. Z., vol. 5, pp. 397-

405 and 456-467; Sept. and Oct. 1952.) Section A, Survey, by Hólzler and Holzwarth, outlines

RECEPTION

V.H.F. Radio Noise--E. G. Hamer. (Wireless World, vol. 59, p. 43; Jan. 1953.) Total-

the general characteristics of the system, whose 4-mc frequency band can be selected at

621.396.62

810

Receiver Production of the VVB-RFT--A.

Blaha. (NachrTech., vol. 2, pp. 261-264;

Sept. 1952.) Short descriptions of the special

features of some of the best types of receiver

produced by this East German nationalized in-

dustry in 1952.

noise measurements were made at typical sites, during the latter part of 1950, at fre-
quencies of 77 and 172 mc. The noise level was much less in the country and in residential areas than in industrial areas; there was no
noticeable difference between the levels obtaining with horizontal and with vertical polarization. The variation of noise level with

will in the range 2.45-2.7 kmc. Section B, Modulation Equipment, by
Holzwarth and Arens, describes in detail the modulation and demodulation arrangements
for the two 12-channel groups. Section C, High-Frequency Equipment, by
Schulz, Piefke and Seibt, gives an account of
the transmitters and receivers, and of the ring-

621.396.62(083.7)

811

Standards on Receivers: Definitions of

Terms, 1952--(PRoc. I.R.E., vol. 40, pp. 1681-

distance from a main road was also investigated. The general atmospheric noise level
was greater in all cases than that due to

modulator type of mixer used at the receiver
input. One transmitter, with apower of 0.5 W, uses a disk-seal triode, Type 2C40, the other,

1685; Dec. 1952.) Standard 52 RE 17.S1.

thermal noise alone, but was less at the higher

with an output of 5 W, uses a Type-2C39A

frequency; in an industrial area the net result

valve. Tuning is effected by varying the length

621.396.621:621.396.662

812

might be appreciably better reception at 172

of the grid cylinder. Control and monitoring

A Method of Band-Spreading--C. A.

than at 77 mc.

equipment is also noted.

Parry. (PRoc. I.R.E., vol. 13, no. 10, pp. 365369; Oct. 1952.) Analysis of a capacitive

621.396/.3971.828

818

Section D, Aerial System, by Wild, v. Kienlin and Simon, describes the lens-type

type of circuit for use in communication re-

Radio Interference Suppression [Book Re-

and parabolic aerials used, and also the filter

·

ceivers shows that it is possible to obtain fre-
quency bands of equal width and constant gain with simple circuits, certain requirements being

viewl--G. L. Stephens. Publishers: Iliffe &
Sons, London, 132 pp., lOs 6d; 2nd ed. 1952. (Electronic Eng., vol. 24, no. 298, p. 585; Dec.

and feeder arrangements. The radiation diagram of a parabolic aerial 3 m in diameter is shown and the operating characteristics of

imposed on the tuning inductors used on each range. Errors due to stray capacitance increase with frequency and cannot be neglected beyond

1952.) A practical guide to the various methods of eliminating interference with radio and
television reception.

aerials respectively 3m, 2m and 1.2m in diameter are compared.

acertain limit, but this limit can be made to lie above the highest operating frequency by
suitable circuit design. A suggested design pro-

STATIONS AND COMMUNICATION SYSTEMS

621.396.5:621.396.8

823

Comparison of Mobile Radio Transmission

at 150, 450, 900, and 3700 mc--W. R. Young,

cedure is outlined.

621.396.621.54:621.385.5

813

Application of the DK92 Tube on 30 hic/s--

H. H. van Abbe and J. Jager. (Electronic Appl.

Bull., vol. 13, pp. 1-7; January, 1952.) Full

circuit details are given of afrequency changer

621.39.001.11: 519.272

819

Contribution to the Statistical Study of

Communications--S. Malatesta. (Alla Fre-

quensa, vol. 21, pp. 163-198; Aug./Oct. 1952.)

An introduction to the application of statistical

methods in network theory, making use of the

Jr. (Bell Sys. Tech. Jour., vol. 31, pp. 10681085; Nov. 1952.) An account is given of tests conducted in and around New York City.
Sufficient test locations were used to give a statistical indication of the trend of performance with frequency variation. Variations of

572

PROCEEDINGS OF THE I.R.E.

April

aerial gain and frequency stability with frequency variation are taken into account. The transmitter power required to achieve the
same coverage at different frequencies depends on the variation with frequency of both path loss and strength of signal required to produce satisfactory communication. The combination of these factors fixes a broad optimumfrequency band at about 500 mc; this frequency band is more suitable than all the others for a
mobile radiotelephone service. The 900-mc band may be preferable to the 150-mc band if
full use is made of aerial gain, but above 900 me performance falls off rapidly.

621.396.712:621.395.6

824

Speech Input Systems for Broadcast Trans-

mitters--S. Hill. (Jour. Brit. I.R.E., vol. 12, pp.

533-541; Oct. 1952.) Text of paper presented

at 1951 Radio Convention, London. Technical

and economic factors involved in the design of the a.f. equipment are considered. Layout

and switching requirements are reviewed.

Microphones, amplifiers, level indicators,

faders, mixers and recording arrangements are discussed.

621.396.712.3:534.84

825

The "Pierre Bourdan n Low-Frequency

[broadcasting] Centre, Paris--L. Conturie. (Onde Bea., vol. 32, pp. 397-410; Oct. 1952.)

A detailed account of the general lay-out of

the establishment, the various studios and con-

trol and recording rooms, with particular refer-

ence to the methods of construction giving good sound insulation between the studios and their

surroundings, and to the treatment of studio

walls, ceilings, etc., to obtain the desired

acoustic properties for faithful recording or

high-quality transmission of programmes. See also 3318 of 1952 (Pujolle).

621.396.712.3:621.396.6

826

Broadcasting-Studio Installations and the

New S.F.R. Equipment--J. Cordonnier and M. Bernard. (Onde élect., vol. 32, pp. 411-422;

Oct. 1952.) The relative merits of centralized and decentralized installations are discussed

and descriptions are given of new equipment

units, developed by the Société Française Radioélectrique, which are economical in use and retain all the essential advantages of the

mixed type of installation. The units have been

designed so that various combinations can be adopted to meet the requirements of different

studios; they include microphone and line amplifiers, attenuators, etc., which can be

assembled into monobloc programme consoles. Performance data are tabulated and illustra-

tions are given of typical units and assemblies, including sound-pickup consoles and consolettes.

621.396.822:621.395.44

827

Intermodulation Noise--J. L. Bordewijk. (Tijdschr. ned. Radiogenooi., vol. 17, pp. 261-

279; Sept./Nov. 1952.) Intermodulation noise

in multichannel telephony systems increases as the signal level rises, in contrast to noise from

other sources, which becomes more noticeable

as the signal level decreases. An optimum

signal/total-noise ratio generally occurs at the

point where intermodulation noise and noise

due to other causes are about equal. The in-

termodulation-noise spectrum can be calculated either from the intermodulation products

or by using correlation functions.

621.396.822:621.396.619.1

828

Signal/Noise Ratio for Various Modulation

Systems--F. L. Stumpers. (Tijdschr. ned.

Radiogenoot., vol. 17, pp. 249-260; Sept./Nov. 1952.) Comparison is made between the two

broad groups of modulation methods respectively using (a) nonquantized and (b) quantized

signals. The signal/noise ratio in the output of

the different systems is related to the signal/noise ratio in the transmission channel and

to the required bandwidth. When nonquantized signals are used the effects of noise

in the successive stages of the system are cumulative; when quantized signals are used (as in p.c.m. and delta modulation) noise is
introduced by the initial quantization process but the system is nearly immune to channel
noise. For ratios of useful energy to noise energy in the transmission channel greater than a threshold value of about 20 db, the quantized system is practically fault-free.

621.396.93

829

Maritime Distress Frequency--W. Blow. (Wireless World, vol. 59, p. 16; Jan. 1953.) The frequency of 1.65 mc hitherto used in European

waters is to be replaced by 2.182 mc from 1st

May 1953; this will be a world-wide distress and calling frequency.

SUBSIDIARY APPARATUS

621-526

830

Servomechanisms, a Survey--G. R. Ar-

thur. (Jour. Brit. I.R.E., vol. 12, pp. 507-516;

Oct. 1952.) Design techniques discussed include

frequency and time analysis and statistical

methods; an indication is given of problems

not yet solved. 55 references.

621-526

831

Nonlinear Servomechanisms--J. Loeb. (Onde ¿lea., vol. 32, pp. 431-437; Nov. 1952.)

The various factors limiting the application of the linear theory of servomechanisms are dis-

cussed, the theory of "filtered" systems using

relays, developed independently by Dutilh

(743 of 1951) and Kochenburger (Elect. Eng.,

N. Y., Aug. 1950), is outlined, and two new criteria applicable to all "filtered" servo-

mechanisms are established. The first criterion is concerned with the possibility of hunting taking place and includes the criteria of Ny-
quist and Kochenburger as special cases. The

second criterion determines the stability of such oscillations of the system. See also

621-526.001.11

832

A Formula for an Integral occurring in the

Theory of Linear Servomechanisms and Con-

trol Systems--H. Buckner. (Quart. Appl.

Math., vol. 10, pp. 205-213; Oct. 1952.)

621.311.6:621.396.615:621.314.7

833

Application of Transistors to High-Voltage

Low-Current Supplies--G. W. Bryan, Jr.

(PRoc. I.R.E., vol. 40, pp. 1521-1523; Nov.

1952.) A transistor oscillator is used to develop the hv required for such devices as Geiger-

Müller counters. The oscillations have a saw-

tooth waveform, the flyback being used for shock excitation of the hv transformer.

621.314.632:546.2891+621.314.7

834

Power Rectifiers and Transistors--R. N.

Hall. (Pnoc. I.R.E., vol. 40, pp. 1512-1518;

Nov. 1952.) Power rectifiers with rectification

ratios as high as 107 can be made by fusing

donor and acceptor contacts to the opposite

faces of a Ge wafer. Analysis of the character-

istics of such rectifiers gives results in good

agreement with experimental values. The

properties of transistors prepared in a similar

manner, and capable of outputs as high as 100

W, are described. At present the operation of

these power units is limited to about 20 kc by

transit-time effects.

621.314.632:546.289

835

A High-Voltage, Medium-Power Rectifier

--C. L. Rouault and G. N. Hall. (Pnoc. I.R.E.,

vol. 40, pp. 1519-1521; Nov. 1952.) A descrip-

tion is given of the operating characteristics of

p-n-junction rectifiers prepared by fusing im-

purity metals to Ge wafers. The addition of

cooling fins enables higher powers to be

handled.

621.314.65

836

The "Nevitron" Mercury-Arc Rectifier--

(Engineering (London), vol. 174, no. 4521, p.

373; Sept. 19, 1952. Overseas Eng., vol. 26, p.

163; Dec. 1952.) Description of a new type of

rectifier with the Hg pool in a Mo cup with external Al cooling fins. Provided the Mo cup is wetted by the Hg to give aconcave meniscus, the cathode spot runs in a continuous line round the edge of the Hg. The cooling system
ensures no excessive emission of vapor. An auxiliary electrode, lifted from the Hg by means of asolenoid, serves to start the arc. The voltage drop across the arc is 12.5V. The
weight of a 50-A 500-V Nevitron is only 2.5 lb, excluding the ignition solenoid. Types with grid control have also been tested. The power required in the grid circuit for full control is only one-thousandth of that for a multianode rectifier.

621.316.722.1:621.387

837

Improved Stabilization from a Voltage-

Regulator Tube--M. D. Armitage. (Electronic Eng., vol. 24, pp. 568-569; Dec. 1952.) By

using a suitable barretter in place of the re-

sistor usually connected in series with avoltage-

regulator tube, a definite improvement in per-

formance is obtained. The barretter type of

circuit is most useful when the load current is relatively high.

621.316.722.1.027.3

838

Stabilizer for Control of High Direct

Voltages--J. Serny. (Rev. gén. ¿led., vol. 61, pp. 411-420; Sept. 1952.) The development

and performance of a stabilizer for direct

voltages of the order of several thousands of

volts are described. The application of the

stabilizer to voltages of any value (a) using as

variable resistor alarge number of triode valves

in series, (b) suppressing the voltage-divider

bridge generally used to control the regulator

system, is also discussed. Rectifier ripple can be eliminated, so that a simple type of filter

can be used.

621.318.435.3:621 311.62

839

The Transbooster--A. H. B. Walker. (Elec-

tronic Eng., vol. 24, pp. 546-550; Dec. 1952.)

Description of circuits in which a transductor is used for regulation of the output voltage of a

rectifier, fed from ac mains, under varying load

conditions. If the transductor is connected on

the dc side of the main rectifier, a smaller

transductor can be used, since it will only have

to handle the total boost voltage required to cover rectifier regulation and mains-voltage variation.

621.316.7:621-526

840

Automatic Feedback Control [Book Review]

--W. R. Ahrendt and J. F. Taplin. Publishers:

McGraw-Hill, New York, 1951, 412 pp., 64s. (Electronic Eng., vol. 24, p. 584; Dec. 1952.)

Theory and applications of servo control sys-

tems.

TELEVISION AND PHOTOTELEGRAPHY

621.397

841

A High-Speed Direct-Scanning Facsimile

System--C. R. Deibert, F. T. Turner and R. H.

Snider. (Elect. Eng. N. Y., vol. 71, p. 784;

Sept. 1952.) Digest of paper presented at

A.I.E.E. General Meeting, January 1952. A

14 description is given of the Western Union

system, which handles copy up to

in. by

15 in. at the rate of 2i in.:/see. Using d.s.b. transmission, the required bandwidth is 30 mc.

The transmitter comprises two identical

scanning units, which are used alternately to save time while copy is changed. The copy-

holding cylinder rotates at 1800 r.p.m., and the controls are partly electromechanical and

partly electronic, with tuning-fork frequency

standards for synchronization.

621.397.5

842

Television Program Origination: The Engi-

neering Technique--D. C. Birkinshaw. (Proc. IEE, part HIA, vol. 99, pp. 43-73. Discussion,

pp. 174-178; April/May 1952.) A comprehen-

sive review of the development of the BBC. television service, including discussion of ap-

paratus and techniques for studio and outside

1953

Abstracts and References

573

broadcasts and for telecine and telefilm recording.

621.397.5

843

Television Program Production Problems

in Relation to Engineering Technique--I.

Atkins. (Proc. IRE, part IIIA, vol. 99, pp.

74-81. Discussion, pp. 174-178; April/May

1952.) Discussion of production planning

camera technique and lighting problems.

621.397.5

844

Determination of the Number of Lines to

be chosen for a Television System, as de-

pendent on the Size of the Receiver Screen--

P. Stroobants. (Onde elect., vol. 32, pp. 438-

444; Nov. 1952.) See 3245 of 1952.

621.397.5:061.4(443.611)

845

The Second Television Salon--(Onde Elect.,

vol. 32, pp. 464-466; Nov. 1952.) Discussion of

design trends for receivers, cr tubes, aerials

and feeders, as exemplified in the equipment on

show at the 1952 Salon. For other accounts see

Télévision, Nov. 1952, No. 28, pp. 255-258;

TS el TV, Nov. 1952, vol. 28, no. 289, pp.

333-335; Toute la Radio, Nov. 1952, vol. 19,

no. 170, pp. 398-402; Radio Télév. prof., Paris,

Oct. 1952, vol. 21, no. 210, pp. 14-15 ...20.

621.397.5:534.86

846

Problems of Sound in Television Pro-

grammes--R. F. A. Pottinger. (Proc. IEE,

Part IIIA, vol. 99, pp. 145-149. Discussion,

pp. 174-178; April/May 1952.)

621.397.5:778.5

847

Television Recording--W. D. Kemp. (Proc.

IEE, part IIIA, vol. 99, pp. 115-127. Dis-

cussion, pp. 174-178; April/May 1952.) Vari-

ous methods of photographic recording on

film, with intermittent or continuous motion

of the film are discussed and the two methods

now used by the BBC are described in some

detail.

621.397.5(091)

848

The History of Television--G. R. M.

Garrott and A. H. Mumford. (Proc. IEE,

part TIIA, vol. 99, pp. 25-40. Discussion, pp.

40-42; April/May 1952.) A review of develop-

ments in various countries. 45 references.

621.397.6:535.317.5

849

A 5:1 Television Zoom Lens--H. H. Hop-

kins. (Proc. IEE, part IIIA, vol. 99, pp. 109-,

112. Discussion, pp. 174-178; April/May

1952.) Performance requirements of zoom

lenses for television are discussed and a lens

system satisfying the requirements, designed

for the BBC, is described. The aberrations of

such lens systems are considered and methods

of correction are outlined.

621.397.6: 621.385.832

850

The Monoscope--R. D. Nixon. (Proc. IEE,

part IIIA, vol. 99, pp. 132-135. Discussion,

pp. 174-178; April/May 1952.) Discussion of

the operating principles and factors affecting

the design of cr tubes for generating a sta-

tionary-picture signal. The picture is printed

on a conducting plate, usually Al, using print-

ing material finally converted to carbon with

a low secondary-emission ratio. Since Al has a

relatively high secondary-emission ratio at low

voltages, scanning of the picture by the cr

beam results in apicture signal being produced

in the lead connecting the Al plate to the final

accelerator electrode. Such devices have re-

cently been used by the BBC for test-card

transmission. See also 2865 of 1938 (Burnett).

621.397.6:778.5

851

A Continuous-Motion System for Televis-

ing Motion-Picture Films--H. E. Holman and

W. P. Lucas. (Proc. IEE, part IIIA, vol. 99,

pp. 95-108. Discussion, pp. 174-178; April/May

1952.) Detailed description of BBC equip-

ment for 35-mm film and of the special equip-

ment required for 16-mm film on account of the

increased magnification from film to viewing screen. The flying-spot system is used.

621.397.611:778.5

852

The Development of aHigh-Quality 35-mm

Film Scanner--T. C. Nuttall. (Proc. ¡RE, (Lon-

don), part IIIA, vol. 99, pp. 136-144. Discussion,

pp. 174-178; April/May 1952.) Detailed de-

scription of BBC equipment using the flying-

spot system.

621.397.611.2

853

A Small High-Velocity-Scanning Television

Pickup Tube--J. E. 1. Cairns. (Proc. IEE,

(London), part IIIA, vol. 99, pp. 89-94. Discus-

sion, pp. 174-178; April/May 1952.) The tube

described, scaled down from one of the super-

emitron type (756 of 1951 McGee)], has a

superior performance and is two or three times

as sensitive as its predecessor. This superiority

is due to increased mosaic storage, which re-

duces the shading signal but increases the

picture lag. The lag is unnoticeable except for

very rapidly moving objects.

621.397.611.2

854

The Influence of Tube Characteristics and

other Factors on Camera Design--L. H. Bed-

ford. (Proc. IEE (London), part IIIA, vol. 99,

pp. 82-88. Discussion, pp. 174-178; April/May

1952.) The principal types of camera tube are

discussed and their transfer characteristics are

shown graphically. Factors affecting camera de-

sign are considered and the principal features of

eight modern cameras are tabulated.

621.397.611.2

855

An Investigation into the Use of Secondary-

Electron Signal Multipliers in Image Icono-

scopes--R. Theile and H. McGhee. (Proc.

IRE, part IIIA, vol. 99, pp. 159-165. Discus-

sion, pp. 174-178; April/May 1952.) By using

an electron-transmissive screen in front of the

first multiplier dynode, complete collection and

sufficient acceleration of the secondary elec-

trons leaving the target can be accomplished.

Further, with a suitable geometrical arrange-

ment of the multiplier and target, uniform

picture generation can be achieved over the

whole target area. A practical assembly is de-

scribed and its performance discussed.

621.397.611.2

856

Design Features of a Television Camera

with a Single-Lens Optical View-Finder--T.

Worswick and J. L. Bliss. (Proc. IEE (London),

part LILA, vol. 99, pp. 166-173. Discussion, pp.

174-178; April/May 1952.) Detailed descrip-

tion of a BBC camera, of relatively small size

and weight, with an optical view-finder located

on top of the camera. A servo focusing-control

system is used.

621.397.62

857

Intercarrier-Sound Television Receivers--
A. Boekhorst. (Electronic Appt. Bull., vol. 13,

pp. 21-33; Feb. 1952.) The basic principles of

the intercarrier-sound system are described

and the requirements imposed on the trans-

mitter and on the response curve of the re-

ceiver are discussed. Three methods of separat-

ing the video and intercarrier signals are con-

sidered and a detailed description is given of

(a) the detector and video amplifier, (b) the

sound channel of a receiver supplying a large

signal to the picture tube.

621.397.62:621.385.3

858

Stable Oscillator for U.H.F. TV Receivers

--Loofbourrow and Morris. (See 900.)

621.397.62:621.396.67

859

Community Antennas bring TV to Fringe

Areas--J. M. Carroll. (Electronics, vol. 25, pp.

106-111; Dec. 1952.) A system representative

of many operating in the U.S.A. is described.

Signals in the various vhf channels are re-

ceived by separate high-gain aerials mounted

on high towers, and are passed through pre-

amplifiers mounted high up the towers. Signals

from odd and even channels respectively are

combined and transmitted via coaxial cables to the tower base, where they are redistributed to separate-channel amplifiers, shifted from high-band to low-band channels, and fed to subscribers by a transmission-line system.
Suitable aerials and amplifiers are discussed.

621.397.621

860

Reactive Time Bases--A. B. Starks-Field.

(Jour. Brit. I.R.E., vol. 12, pp. 519-532. Dis-

cussion, p. 532; Oct. 1952.) Text of paper pre-

sented at 1951 Radio Convention, Cambridge.

High-efficiency line-deflection circuits for large-

screen television tubes are discussed. Various

methods are described for recovering the energy

in the deflecting field at the end of the scan;

this energy can either by returned to the h.v.

line or used to boost the voltage of the driver

stage. The design of booster circuits is dis-

cussed with reference to efficiency, linearity

and convenience of operation from h.v. sup-

plies of the order of 200 V. Particular attention

is paid to the design of the transformer, which

may be either an autotransformer or a multi-

winding type. A system for operating directly

on to high-impedance deflection coils is briefly

mentioned.

621.397.621.029.63

861

One-Channel Converter for U.H.F. Tele-

vision--Wen Yuan Pan. (Electronics, vol. 25,

pp. 134-138; Dec. 1952.) Printed inductors and

Ge-diode mixers are used in a commercially

available converter for shifting signals from

any given uhf channel to a selected channel in

the lower vhf band. The whole of the uhf tele-

vision band is covered by the grounded-

anode oscillator circuit.

621.397.621.2:621.318.2

862

A New Focusing Unit for Television Picture

Tubes--P. van Tilburg and J. A. Verhoef.

(Electronic Appl. Bull., vol. 13, pp. 37-43;

March/April 1952.) The properties of ferrox-

dure which make it particularly suitable for

use in magnetic focusing units are described

and details are given of a unit which uses two

annular ferroxdure magnets. The strength of

the focusing field is adjusted by variation of

the separation of the two rings, which can be

varied from 1mm to 12 mm to cover a range

of beam voltages from 5 kV to 20.5 kV.

621.397.7:621.316.7

863

Television Control-Room Lay-Out--R. D.

Chipp. (Tele-Tech, vol. 11, pp. 48-51; Oct.

1952.) Separate arrangements for audio, video,

and direction control result in greater efficiency

of operation. Suggested plans for large, me-

dium, and small studios are presented and dis-

cussed.

621.397.7:628.972

864

Television Studio Lighting Equipment--

S. L. Johnson. (Proc. IEE, part IIIA, vol. 99,

pp. 113-114. Discussion, pp. 174-178;

April/May 1952.)

621.397.7:628 972

865

Television Lighting Technique--H. O.

Sampson. (Proc. IEE, part IIA, vol. 99, pp.

150-158. Discussion, pp. 174-178; April/May

1952.) An account of arrangements adopted in

BBC studios.

621.397.7:628.972:621.327.4

866

Discharge Lamps for Television Studios--

E. H. Nelson and W. A. Price. (Proc. LEE,

part IIIA, vol. 99, pp. 128-131. Discussion,

pp. 174-178; April/May 1952.)

621.397.82:621.396.621

867

The Maximum Permissible Interference

Radiation from U.S.W. Receivers--(Radio

Tech. (Vienna), vol. 28, pp. 425-426; Oct.

1952.) With the introduction of television in

Germany, principally on frequencies in the

band 174-216 mc, interference from the

second harmonic of the local oscillator of s.w.

f.m. broadcasting receivers has been ex-

perienced. It has been decided that such in-

574

PROCEEDINGS OF THE I.R.E.

April

terference must be reduced below the level of 30 µV/m at a distance of 30 m from an aerial
connected to a receiver. Equipment suitable for making the necessary measurement is noted.

621.397.822

868

Noise Measurements on Television Trans-

missions--R. Rasch. (Fernmeldetech. Z., vol. 5,

pp. 440-444; Oct. 1952.) Noise voltages of am-

plifiers are usually measured in terms of

effective values, while for television picture

signals peak values are used. Equipment is

described for cro comparison of peak and

effective values of noise voltages. A correction

of 15 db should be applied when comparing

effective values with peak-to-peak values. A

method of determining the permissible noise

level in atelevision transmission system is out-

lined and illustrations are given of the effect on

picture quality of a progressive reduction of

the signal/noise ratio.

621.396/.3971.828

869

Radio Interference Suppression [Book Re-

viewj--Stephens. (See 818.)

TRANSMISSION

621.396.61 :621,396.611.3: 621.396.67

870

Transmitter Combining Circuits--A. R. A.

Rendall and G. A. Hunt. (Elearonic Eng., vol.

24, pp. 550-552; Dec. 1952.) Description of

typical circuits used at BBC. unattended sta-

tions for coupling two or more transmitters,

operating on a common frequency, to a single

aerial. For transmitter powers <1 kW aspecial

hybrid coil, wound on an iron-dust core, has

been developed. The circuits used include both

hybrid and bridged-T circuits.

TUBES AND THERMIONICS

621.314.6/.7:621.396.822

871

On the Theory of Noise in P-N Junctions

and Related Devices--R. L. Petritz. (Pgoc.

I.R.E., vol. 40, pp 1440-1456; Nov. 1952.)

Noise resulting from fluctuations inherent in

the electronic system of a p-n junction is in-

vestigated and found to be a result of fluctua-

tions of the concentration of the minority car-

riers. A noise theory based on a lumped-

parameter representation of a p-n junction is

developed, and an equivalent circuit, with ap-

propriate noise generator, is derived. Noise

characteristics of p-n-junction rectifiers and

transistors are analyzed. The available noise

power of a p-n-junction rectifier is voltage de-

pendent, its equation resembling that of

Weisskopf for point-contact rectifiers. The

noise figures of p-n-junction transistors are of

the order of unity and are independent of size

and current density. A comparison is made, as
regards noise, between point-contact and p-n-

junction rectifiers and transistors, using the

Wisskopf noise formula (M.I.T. Rad. Lab.

Series, No. 133, 1943) for the point-contact

devices. A relation between the noise spectrum

and the admittance of a p-n-junction is ob-

tained. Fluctuation noise constitutes only a

part of the measured noise of point-contactand

p-n-junction rectifiers and transistors. Another

source of noise, connected with control of mean

current, is required to account for (a) the noise

figures of p-n-junction and point-contact tran-

sistors being appreciably greater than unity,

(b) the large difference between the noise fig-

ures of p-n-junction and point-contact transis-

tors, (c) the 1/f law of the frequency spectrum

of the measured noise.

621.314.63:546.289

872

On Some Transients in the Pulse Response

of Point-Contact Germanium Diodes--M. C.

Waltz. (Pnoc. I.R.E., vol. 40, pp. 1483-1487;

Nov. 1952.) To explain the hole-storage effect

noted by Michaels and Meacham (1817 of

1950) a hypothesis is proposed which postu-

lates the presence of traps in the Ge p layer

near the point electrode. Measurements and

calculations indicate trap densities of the order of 1016/ems, trap depths in the energy band of about 0.3 eV, and capture cross-section diam-
eters of about 0.3 A.

621.314.7

873

Present Status of Transistor Development

--J. A. Morton. (Pgoc. I.R.E., vol. 40, pp.

1314-1326; Nov. 1952.) Reprint. See 2651 of

1952.

621.314.7

874

Effects of Space-Charge-Layer Widening in

Junction Transistors--J. M. Early. (Pgoc.

I.R.E., vol. 40, pp. 1401-1406; Nov. 1952.)

Some effects of the dependence of the thickness

of the collector barrier on collector voltage are

analyzed. The thickness of the base layer de-

creases as collector voltage increases, resulting

in an increase of the current-gain factor a and a

decrease of the emitter voltage required to

maintain any given emitter current. These effects lead to the introduction of two new ele-

ments in the small-signal equivalent circuit:

(a) the collector conductance, which is propor-

tional to emitter current and varies inversely

with collector voltage; (b) the voltage-feedback

factor, which is independent of emitter current

but varies inversely with collector voltage.

621.314.7:537.311.33

875

Transistor Electronics: Imperfections, Uni-

polar and Analog Transistors--Shockley. (See

146.)

621.314.7: 546.289

876

A Developmental Germanium P-N-P Junc-

tion Transistor--R. R. Law, C. W. Mueller,

J. I. Pankove (Pantchechnikoff) and L. D.

Armstrong. (Pgoc. I.R.E., vol. 40, pp. 1352-

1357; Nov. 1952.) A transistor of the p-n-p

junction type can easily be made in the labora-

tory by diffusing indium into opposite faces of

a single-crystal n-type Ge wafer. The charac-

teristics of such units are illustrated by experi-

mental curves obtained in tests of over 100

units.

621.314.7:546.289

877

Fused-Impurity P-N-P Junction Transis-

tors--J. S. Saby. (Pgoc. I.R.E., vol. 40, pp.

1358-1360; Nov. 1952.) Transistors of the

p-n-p-junction type were produced by fusion

of acceptor impurities so as to create p-type

areas on opposite faces of awafer of n-type Ge.

The power dissipation of...such units can be in-

creased by the addition of metal cooling fins.

The current multiplication factor a is nearly

constant at about 0.95 up to 120°C and de-

creases slightly above this temperature. The

power gain is high and noise figure low.

621.314.7:546.289

878

Four-Terminal P-N-P-N Transistors--J. J.

Ebers. (Pnoc. I.R.E., vol. 40, pp. 1361-1364;

Nov. 1952.) A p-n-p-junction transistor and

one of the n-p-n-junction type can be inter-

connected in such away as to have an equiva-

lent circuit identical with that of a p-n-p-n

transistor. A simplified equivalent circuit is

obtained for the case where the p-n-p-n transis-

tor is used as a grounded-base hook-collector

transistor.

621.314.7:546.289

879

A Unipolar "Field-Effect" Transistor--W.

Shocldey. (Pgoc. I.R.E., vol. 40, pp. 1365-

1376; Nov. 1952.) The field-effect transistor

consists of a layer of p-type material sand-

wiched between two layers of heavily doped

n-type material, termed n+. The working cur-

rent is carried by hole conduction in the p-type

layer, between terminals consisting of heavily

doped p+ inserts. With reverse bias across the

p-n junctions, the current flows in a channel

of p-type material bounded by two space-

charge regions with negligible carrier con-

centration. A theory of the action of such

devices is presented, the new terms used for the

various electrodes are defined, and design calculations are made for a unit made from Ge.

621.314.7:546.289

880

Junction Fieldistors-0. M. Stuetzer.

(Pitoc. I.R.E., vol. 40, pp. 1377-1381; Nov.

1952.) A description is given, with theory, of an

amplifying device with high-impedance input

and low-impedance output, which uses an

auxiliary electrode close to a p-n junction to

control the surface conductivity in the neigh-

bourhood of the junction. The arrangement is

similar to those previously described (3198 of

1950). A frequency cut-off in the AF range will

limit the application of the device in its present

form.

621.314.7:546.289

881

Theory of Alpha for P-N-P Diffused-

Junction Transistors--E. L. Steele. (Pgoc.

I.R.E., vol. 40, pp. 1424-1428; Nov. 1952.)

Equations are developed for the emitter and
collector currents for p-n-p-junction transis-

tors, and the current-gain factor a is deduced.

The IF value of a and its HF cut-off value are

markedly dependent on the thickness of the

n-type "base" region, the HF characteristics

being better when this thickness is small. In

grounded-emitter applications the HF charac-

teristics depend more directly on the lifetime

of holes, and show only second-order depend-

ence on the base thickness; the shorter the life-

time the higher the cut-off frequency.

621.314.7:546.289

882

Effect of Electrode Spacing on the Equiva-

lent Base Resistance of Point-Contact Transis-

tors--L. B. Valdes. (Pstoc. I.R.E., vol. 40, pp.

1429-1434; Nov. 1952.) An expression for the

equivalent base resistance rb is derived and is

checked experimentally Electrode spacing,

and the thickness and resistivity of the Ge
slice, have major effects on the value of rb.

621.314.7:546.289:536.49

883

Variation of Transistor Parameters with

Temperature--A. Coblenz and H. L. Owens.

(Pgoc. I.R.E., vol. 40, pp. 1472-1476; Nov.

1952.) Measurements were made of the varia-

tions with temperature of the parameters of 20

Western Electric Type-I698 and Type-1768

transistors over the range 25-85°C. The results

are shown graphically and indicate that these

transistors can operate satisfactorily for many

small-signal applications up to about 60°C, the

gain, e.g., being decreased by only about 2db

at this temperature.

621.314.7: 621.3.016.352

884

The Control of Frequency Response and

Stability of Point-Contact Transistors--B. N.

Slade. (Pgoc. I.R.E., vol. 40, pp. 1382-1384;

Nov. 1952.) Satisfactory stability and fre-

quency characteristics have been obtained by

control of the point-contact spacing and the

resistivity of the Ge used. By means of the

methods outlined, transistors have been pro-

duced that can oscillate at frequencies con-

siderably higher than 100 mc, one reaching 300

mc.

621.314.7+1621.314.632 :546.289

885

Power Rectifiers and Transistors--Hall.

(See 834.)

621.314.7:1621.396.615+621.396.645

886

A Junction-Transistor Tetrode for High-

Frequency Use--Wallace, Schimpf and Dick-

ten (See 677.)

621.314.7:621.396.822

887

An Experimental Investigation of Transistor

Noise--E. Keonjian and J. S. Schaffner.

(Pgoc. I.R.E., vol. 40, pp. 1456-1460; Nov.

1952.) Transistor noise is discussed and meth-

ods of measuring it are described. Experi-

mental results give noise figures for point-

contact transistors of about 50 db, while for

p-n-junction transistors the values may be as

low as 10 db at 1kc. The noise figure of point-

1953

Abstracts and References

575

contact transistors was found relatively independent of the dc operating point, but for junction transistors the noise figure may vary
considerably with collector voltage and to some extent with emitter current.

621.383.5

888

New Phototlectric Devices utilizing Car-

rier Injection--K. Lehovec. (Pnoc. I.R.E., vol.

40, pp. 1407-1409; Nov. 1952.) The devices

described are: (a) the photomodulator, which

permits modulation of a light beam by the

change in absorption due to injected carriers;

(b) the graded-seal junction, which is prepared

by fusing together two materials at atempera-

ture intermediate to their two melting points,

with subsequent slow cooling. A theory of the

phenomenon of electroluminescence [1341 of

1951 (Payne et al.)] is proposed which is based

on the injection of minority carriers.

621.383.5

889

Properties of the M-1740 P-N Junction

Photocell--J. N. Shive. (Pnoc. I.R.E., vol. 40,

pp. 1410-1413; Nov. 1952.) Description of a

cell evolved from the practical unit described

by Pietenpol (2302 of 1951) and the work of

Goucher et al. (1669 of 1951). The cell is only

X X13/16 in., has low dark current, low noise

and high sensitivity.

621.383.5:546.289:621.397.611.2

890

Use of the Flying-Spot Scanner to Study

Photosensitive Surfaces--J. I. Pantchech-

nikoff, S. Lasof, J. Kurshan and A. R. Moore.

(Rev. Sci. Instr., vol. 23, pp. 465-467; Sept.

1952.) Variations of photosensitivity over the

surface of a large-area Ge photocell [2656 of

1952 (Pantchechnikoff)] are investigated by

scanning with aflying spot from acr tube and

using the output of the photocell, after am-

plification, to control the beam intensity of a

second cr tube.

621.385:621.396.822

891

A New Method of Calculating Microwave

Noise in Electron Streams--J. R. Pierce.

(Pnoc. I.R.E., vol. 40, pp. 1675-1680; Dec.

1952.) The approach to the problem is es-

sentially the sanie as that of North (3420 of

1940). Linearized equations are used to calcu-

late a frequency component of the noise ex-

cited in an electron beam by a charge having

a velocity different from the mean velocity of

the beam. Noise maxima and minima are found

for a beam traversing a drift space. Results

agree with values calculated by the Rack-

Llewellyn-Peterson method (see "Traveling-

Wave Tubes," J. R. Pierce, Chap. 10).

621.385.032.21:061.3(47)

892

Conference on Cathode Electronics--I.

Dykman. (Zh. lekh. Fis., vol. 22, pp. 175-182;

Jan. 1952.) Summaries are given of the papers

read at a conference held in Kiev on 4th-9th

June 1951. The papers are grouped under the

following headings: (a) general questions on

the operation and structure of cathodes, (b)

photoelectric effect, (c) secondary electron

emission, (d) thermoelectron emission, (e)

cathodes under discharge conditions or ionic

bombardment

621.385.032.213:546.431.221

893

The Electronic Properties of Barium Sul-

flde--W. Grattidge and H. John. (Jour. Appi.

Phys., vol 23, pp. 1145-1151; Oct. 1952.) Re-

sults are reported of measurements made of

the electron emission from BaS used as cathode

coatings in planar diodes. For the most active

of the samples used, the emission at tempera-

tures of 900° K and over was comparable with

that from pure BaO. Work function, con-

ductivity and thermoelectric power were de-

termined and the effect of Fe as an impurity

was studied. The evaporation rate was found

to be much less than that of BaO.

621.385.032.216:537.311.32

894

Conductivity of Oxide Emitters--R. C.

Hughes and P. P. Coppola. (Phys. Rev., vol. 88, pp. 364-368; Oct. 15, 1952.) Measurements
of the electrical conductivity of a (BaSrCa)0 emitter over arange from room temperature to 1100°K indicate the existence, in well activated
cathodes, of a low-temperature conduction mechanism with an activation energy as low as
0.05 eV. A high-temperature conduction mechanism of 1-eV activation energy is noted
for the temperature at which appreciable
electron emission can be drawn. Exposure to Xe at apressure of 25 atm causes amarked decrease of conductivity in the high-temperature
range. These results are considered to confirm Loosjes and Vink's hypothesis (3208 of 1950) that in the high-temperature range conduction
takes place mainly through space currents in the pores in the material. The low activation
energy of the low-temperature conduction
mechanism indicates that this conduction probably occurs in a monolayer of Ba on the
surface of the oxide.

621.385.032.216:537.533.8

895

Secondary Electron Emission from Barium

Oxide--J. Woods and D. A. Wright. (Brit.
Jour. Appi. Phys., vol. 3, pp. 323-326; Oct.

1952.) Report of an experimental investigation

of the influence on the secondary-emission co-

efficient, 6, of the methods of preparing and

operating the BaO layers. Variation of b with

temperature is small between room tempera-

ture and 600°C. For evaporated films under

steady bombardment at 240 V the value of 45

is about 3for thickness 106 cm and about 2for

thickness 10-6 cm; with pulsed operation 6 is

considerably larger. For sprayed coatings the

value of ôis about 2for both steady and pulsed

operation. Over a long period of operation the

value of 6falls and decomposition of the oxide

occurs.

621.385.032.216:546.431/.4321-31

896

Electrical Conductivity and Thermoelectric

Power of (BaSr)0 and BaO--J. R. Young.
(Jour. Appi. Phys., vol. 23, pp. 1129-1138;

Oct. 1952.) Report of an investigation of the

temperature dependence over the range 1100°-

300°K of the properties of oxide-cathode coat-

ings at different states of activation and with

Ni bases of different purities. Details are given

of experimental procedure. No significant

differences were found between the properties

of BaO and (BaSr)0. Thermoelectric-power

/temperature curves confirm theory developed

by Hensley (737 above). Results cannot be ex-

plained on the basis of a simple one- or two-

level semiconductor model, but give general

support to the pore-conduction theory.

621.385.032.216:621.386

897

A Study of the Oxide-Coated Cathodes by

X-Ray Diffraction Method: Part 1--E.

Yamaka. (Jour. Appi. Phys., vol. 23, pp. 937-

940; Sept. 1952.) See 1158 of 1952

621.385.032.216.2

898

Latest Disc-Cathode Developments--(Elec-

fronics, vol. 25, pp. 236 .. 252; Nov. 1952.)

C.r.-tube cathodes are described in which a

ceramic disk is used as insulator between

cathode and first grid. Improvements intro-

duced include the use of more efficient alloys

for cathode caps, techniques for maintaining

critical spacings constant during long pro-

duction runs, reduction of electron leakage

across the ceramic disk and between heater

and cathode, and elimination of heater shrink-

age caused by damage during insertion.

621.385.032.24: 537.533

899

Origin of Thermal Grid Emission and In-

vestigations on its Elimination--H. Klippen.

(Nachr Tech., vol. 2, pp. 246-247; Aug. 1952.)

The results of investigations of grid currents in

tubes with grids and anodes of various mate-

rials and constructions show that such currents

can be largely reduced by using grid materials

with a high work function, by adopting aform
of construction in which grid heating by radiation from the cathode is avoided as far as possible, and by choice of a suitable cathodeactivation process.

621.385.3:621.397.62

900

Stable Oscillator for U.H.F. TV Receivers

--K. E. Loofbourrow and C. M. Morris.

(Electronics, vol. 25, pp. 118-121; Dec. 1952.)

The Type-6AF4 acorn oscillator triode is de-

scribed. The influence of construction details on operating parameters is discussed. Power

output is increased by silver-plating the leads;

an increase from about 90 to 150 mW is observed for samples operating at about 1 mc.

Use of the tube in a receiver·with an IF of

41.25-45.75 mc is discussed; the required oscil-

lator frequency range (in the region of 930 mc)

is obtained by using the tube with a X/2 external line. Circuits are suggested capable of

holding the drift to 500 kc in intercarrier-

sound receivers.

621.385.832

901

The Optimum Space-Charge-Controlled

Focus of an Electron Beam--D. L. Hollway.

(Aust. Jour. Sci. Res., Ser. A, vol. 5, pp. 430-

436; Sept. 1952.) A theoretical investigation is made of the defocusing of a beam of circular

cross-section due to space charge; expressions

for the condition of optimum focus are derived

from the equations of the beam profile. Over a

wide range of tubes of spot radius the optimum-

focus expressions may be replaced by simpler

formulae useful for dealing with electron-beam

design problems.

621.387

902

The Thyratron as Switching and Control

Tube and its Industrial Application Possibilities

--R. Hubner. (Bull. schweiz. elektrotech. Ver.,

vol. 43, pp. 760-764; Sept. 20, 1952.)

621.387.032.212

903

Inertia Effects in Cold-Cathode Tubes--

M. O. Williams. (Sfrowger Jour., vol. 8, pp* 106-117; July 1952.) The type of discharge

in cold-cathode tubes is examined both for the

current-growth and current-decay periods.

Measurement methods are outlined and typical

oscillograms of current rise and decay with recurrent pulses are shown. Investigations with

small-amplitude ac superimposed on the dc

glow discharge reveal inertia effects of con-

siderable magnitude and also complex-im-

pedance effects. Results obtained on several

types of tube are given in graph form; they

show surprisingly high values of apparent in-

ductance and appreciable values of effective

resistance. The origin of the quadrature current

in such tubes is discussed.

621.396.615.141.2

904

Oscillations in a Nonslotted Magnetron in

connection with Amplification by Space-Charge

Waves--R. Warnecke, H. Huber, P. Guénard

and O. Doehler. (C.R. Acad. Sci. (Paris), vol.

235, pp. 493-494; Aug. 25, 1952.) A formula

for the frequency of oscillations in a whole-

anode magnetron is confirmed experimentally.

From a "cliocotron ° oscillator of this type in which the frequency can be changed within

wide limits by adjustment of the anode voltage,

about 50mW power has been obtained over a

frequency band of more than an octave around

800 Mc/s.

621.396.622.6:546.28

905

Silicon P-N Junction Alloy Diodes--G. L.

Pearson and B. Sawyer. (Pitoc. I.R.E., vol. 40,

pp. 1348-1351; Nov. 1952.) Acceptor or donor

impurities are alloyed with n- or p-type Si to

produce p-n-junction diodes with reverse cur-

rents as low as 10-18 A, rectification ratios as

high as 108 at 1V, stable Zener voltage which

can be fixed, during the production process, at

a value between 3 V and 1kV, and ability to

operate at temperatures as high as 300°C.

576

PROCEEDINGS OF THE I.R.E.

621.396.822

906

Symposium on Noise. General Introduction

--Casimir. (See 693.)

621.396.822:621.385.13

907

Valve Noise at Very High Frequencies--G.

Diemer. (Tijdschr. ned. Radiogenoot., vol. 17,

pp. 281-301; Sept./ Nov. 1952.) At frequencies

>108 cps, for which electron transit times are

not negligible, the finite duration and particular

shape of current pulses induced by the in-

dividual electrons give rise to additional noise;

total-emission noise increases considerably and

space-charge smoothing becomes less effective.

The correlation between the various causes of

noise is emphasized, and the difference between
the transmission process through the tube for signal and for noise is indicated. Various triode
circuits are discussed in relation to noise factor, the value of which is affected by the feedback in the circuit.

MISCELLANEOUS

621.396.822

908

Symposium on Noise. Historical Introduc-

tion--J. L. van Soest. (Tijdschr. ned. Radio-

genoot., vol. 17, pp. 197-198; Sept./Nov. 1952.)

The subject is traced from Brown's investiga-

tions in 1827 of the movements of particles.

In present-day electrical engineering the greatest emphasis is laid on signal/noise ratio, on account of its importance in relation to the
transmission of information.

621.396/.397

909

Electronics for Communications Engineers

[Book Reviewi--J. Markus and V. Zeluff. Pub-

lishers: McGraw-Hill, New York, 601 pp.,

$10. (Paoc. I.R.E., vol. 40, p. 1741; Dec. 1952.)

A collection of papers published in Electronics

during the past five years on the design of com-

munication, broadcasting, television and radar

equipment.

10-Turn Helipot Highlights

Whenever circuits call for precision

From the basic Helipot principle, model variations have been developed to meet new requirements:

and high resolution in compact space...
Helipot There's a 10-turn
to meet your requirements

With the development of the original HELIPOT--

the first multi-turn potentiometer--an entirely new principle of

potentiometer design was introduced to the electronic industry.

It made possible variable resistors combining high resolution and

high precision in panel space no greater than that required for

conventional single-turn potentiometers.

The Helipot Principle..,

High resolution and precision settings require along slide wire. But by coiling a resistance element into a helix, it is possible to gain desired resolution and precision without

wasting panel space. This principle is applied in various Helipot models

with slide wires ranging from 3to 40 helical turns.

Advantages are immediately apparent. In the case of the widely-used 10-turn Model A Helipot, for example, a 45" long slide wire--coiled into ten helical turns--is fitted into a case 134" in diameter, and 2" in length. Another advantage of the 10-turn pot is that, when equipped with a turns-indicating RA Precision DUODIAL, slider position can be read
directly as a decimal, or percentage, of total coil length traversed.

10-TURN HELIPOT
No. of turns Resistance Range
Resistance Tolerance: Standard Best
'Linearity Tolerance: Standard Best
Power rating © 40°C Mechanical Rotation
Electrical Rotation
Starting Torque Running Torque Net Weight

MODELS --CONDENSED SPECIFICATIONS

Model A 10
10 ohms to 300,000 ohms

Model AN 10
100 ohms to 250,000 ohms

Model AJ 10
100 ohms to 50,000 ohms

+ 5% +I%

4- 5% +1%

-1- 5% -1- 3%

+0.5% +0.05% (IK ohms and above) 5watts 3600' +4*
--0 ° 3600° +4*
--0* 2on. in. 1.5 oz. in.
4oz.

+ 0.5%

+ 0.025% (5K ohms and above)

5watts

3600° +1° --0*

3600° +1° --0°

1.0+.3 on. in.

0.6+.3 on. in.

_

4oz.

+0.5% ±0.1% (above 5K ohms)
2watts 3600° +12'
--0° 3600° +12°
--0* .75 on. in. .60 on. in.
1on.

'i.e. INDEPENDENT LINEARITY. The above linearity tolerances are based on the fol-

lowing definition recently proposed to clarify and standardize nomenclature related to

precision variable resistors. ... "Independent linearity is the maximum deviation in per-

cent of the total electrical output of the actual electrical output at any point from the

best straight line drawn

through the output

ne .mrAo. 1...11·AWA

versus rotation curve. (This line shall be

- -

measured through the

extent of the effective

electrical angle.) The

slope and position of

the straight line from

which the linearity de-

viations are measured

must be so adjusted as

to minimize these de-

viations."

Model AHelipot

the original 10-turn Helipot-- provides a resolution from 12 to 14 times that of conventional single-turn potentiometers of same diameter (1 3/ 4 "), linearities as close as +0.05% in resistances as low as 1K ohms.

The same multi-turn principle is also available in 3 turn units (Model C), and larger-diameter units of 15 turns (Model B), 25 turns (Model D), and 40 turns (Model E)--a type for every application from 5 ohms to 1 megohin.
2

BRUSH

·32 MO" THREADS

·CC00 23000a

2à-±J

4062 an LOCATING LUG et»

Model AN Helipot

an ultra-precision version of the basic 10-turn Helipot. Produced in volume to extremely close electrical and mechanical tolerances, this unit features precision ball bearings (Class 5), servo mounting lid, plus linearity tolerance as close as +0.025% as low as 5K. A 3-turn unit (Model CN) is also available.

Models AN and CN are particularly recommended for precise

servo-mechanism applications and represent the most ad-

vanced design and highest quality available today in the field

of precision potentiometers.
le>

ei THREAD 8-32 NC-2 ·è

062 All-

2 -

DEEP 3 EQUALLY SPACED MOUNTING HOLES

°62

1250 13 C

Model AJ Helipot
a 10-turn miniature Helipot only 34" in diameter, weighs 1oz., has slide wire 18" long. Also available with servo mounting (Model AJS) and servo mounting with ball bearings (Model AJSP). Linearitics as close as 4- 0.1% as low as 5K.

Designed for long life under severe operating conditions, the AJ Series is widely used where small site and weight are vital.

THREAD /ADM
1250 CA

-12 MEE -2

PANEL NUT IA INTERNAL Motu LOCAWASEIER PROYIOED
Design details on above units are sub ect to change without notice. Certified (leanings available upon request.
t2ffly_HAllip2it is able to supply--in volume--multi-turn helical potentiometers with special features to meet your particular needs... Special Shafts, Extra Spot Welded Taps at any position, Ganged Assemblies (except AJ), Special Temperature Coefficients, etc. Send us your requirements!

CPO COP. er 1110111,01·Mt Ile/MAII·1111111

PM« 1.1.1.1 /OM
1.{611.. (1.11141 umAlwre

For complete details contact

E

Helipot

your nearby Helipot rep eeeee tative. Or write direct.
CORPORATION

A subsidiary of Beckman InsiTIMICIUS, Inc. SOUTH PASADENA 6, CALIFORNIA Field Offices: Boston, New York. Philadelphia, Rochester. Schenectady, Cleveland, Deena. Chicago, St. Louis, Los Angeles, Seattle. Dallas, High Point, N. C. and Fort Myers. Florida. In Canada: J. S. Root, Toronto.
Export Agents: Frathom Co., New York 36, New York.

PROCEEDINGS OF THE I.R.E.

195$

65.`

TRANSIENT ANALYSIS
Type 513-D-High Writing Rate Oscilloscope
TWELVE KV accelerating potential provides the light intensity necessary for photographic recording of single highspeed sweeps, or visual observation of pulses of low duty cycle. Increased brightness and removal of residual charge from previous sweeps result from use of metallized CRT screen.
TRIGGERED SWEEPS. Signals producing 0.5 cm or greater deflection will trigger the sweep. Trigger pulses may be as short as 0.05 /tsec. Sweep easily made recurrent when desired.
WIDE BAND. Factory adjusted for optimum transient response, the Type 513-D distributed vertical amplifier has a risetime of 0.025 rsec with no appreciable ringing or overshoot.

VERTICAL AMPLIFIER
Sensitivity
0.3 v/cm to 100 v cm dc
0.03 v/cm to 100 y/cm ac
Transient response 0.025 µsec risetime
Signal delay 0.25 lsec

CALIBRATING VOLTAGE Square wave, approximately 1kc Seven ranges, 0.05 yto 50 v Accurate within 3% of full scale
TIME BASE 0.1 µsec/cm to 0.01 sec/cm Continuously variable Accurate within 5% of full scale
REGULATION All dc voltages electronically regulated

WAVEFORMS AVAILABLE Calibrating voltage Gate Delayed gate Delayed trigger Sweep sawtooth Trigger rate generator (200 to 5000 cps)
SELF-CONTAINED Weight 79 lbs.

TEKTRONIX Type 513-D Cathode-Ray Oscilloscope, $1650 f.o.b. Portland, Oregon

TEKTRONIX, Inc.
P. 0. Box 8318, Portland 7, Oregon ·Cable: TEKTRONIX

"lb\
· ·t: ·· '

tts · ·
· s
·.0

· ·"·· ·· · · · ·-·

Type 524-D

·· 0;0 ·

Television Scope
Designed especially for TV Broadcasters, the Type 524-D permits observation of a field one line at a time with push-button shift to corresponding line in opposite field. New magnifier, 3x or 10x, expands sweep to right and left of center. Time markers for accurate sync pulse timing. TIME BASES - 0.1 tsec/cm to 0.01 sec/cm
continuously variable, accurate within .5%·
VERTICAL SENSITIVITY dc to 10 mc -0.15 v/cm to 50 v/cm 2cps to 10 mc - 0.015 v/cm to 50 v/cm
TRANSIENT RESPONSE - 0.04 µsec risetime
SIGNAL DELAY - 0.25 µsec
5" CRT - flat-faced, 4 kv accel. potential
Type 524-D - $1180

Type 315-D

Wide Time Base Range

Read time and amplitude directly from the screen. 24 accurately calibrated time bases...12 accurately calibrated vertical sensitivity positions.

TIME BASES - 0.1 µsec/div to 5 sec/div

VERTICAL SENSITIVITY dc to 5 mc -0.1 v/div to 50 v/div 5 cps to 5 mc 0.01 v, div to 50 v/div

TRANSIENT RESPONSE - 0.07 µsec risetime

3" CRT - high definition, flat-faced

Type 315-D for use on 50-60 cycle line

$770

Type 315-D for use on 50-800 cycle line

$785

Prices f.o.b. Portland, Oregon

These three and other oscilloscopes fully described in

·

the 1953 Tektronix Catalog. Write to the above address.

·

Industrial Engineering Notes1
TELEVISION NEWS
The Italian government is buying a considerable amount of television equipment from aBritish firm for use in its studios at Rome and Milan, according to reports reaching the Department of Commerce. Medium-power transmitting equipment also is being purchased for use at Rome and Pisa. The equipment is expected to be used to expand the services of the present experimental station of the official Italian broadcasting corporation, Radio Audizione Italiana (R.A.I.), into a fullscale network. When completed, most of Italy would receive television service from transmitters located in nine main population areas. A two-way radio link is proposed between Rome and M ilan, with programs originating in these two cities. ... Speaking before the National School Boards Association Convention last week in New Jersey, Paul A. Walker, Chairman of the FCC, said that now was the time for educators, school board members, trustees, legislators and governors to take definite and timely action to support plans in the respective communities for the utilization of the 242 channels for non-commercial educational television stations. Chairman Walker pointed out that the end of the one-year reservation period for educational TV channels is June 2, 1953, and that these channels set aside by the FCC for educational TV cannot be held indefinitely beyond this deadline. ...A total of 6,174,505 television sets were shipped to dealers during 1952, RMTA has estimated. This compares with 1951 TV set shipments to dealers of 5,095,563 units.... The FCC granted construction permits for new television stations recently to bring the total authorizations since the lifting of the "freeze" last summer to 254. Authorized since January 28 have been:
Fort Dodge, Northwest Television Co., Channel 21.
Madison, Wis., Bartell Television Corp., Channel 33.
Roswell, N. Mex., John A. Barnett, Channel 8.
Salem, Ore., Lawrence A. Harvey, Channel 24.
Johnson City, Tenn., WJHL, Inc., Channel 11.
Memphis, Tenn., Harding College, Channel 13.
Temple, Texas, Bell Publishing Co., Channel 6.
Tyler, Texas, Jacob A. Newborn, Jr,
Channel 19.
Charlottesville, Va., Barham & Barham, Channel 64.
Lansing, Mich., Lansing Broadcasting Co., Channel 54.
Billings, Mont., The Montana Network, Channel 2.
(Continued on page 72A)
The data on which these NOTES are based were selected by permission from Industry Reports, issues
of February 6, 13. 20. and February 27. published
by the Radio-Television Manufacturers Association. whose co-operation is gratefully acknowledged.

Ott \

PROCEEDINGS OF THE I.R.E.

April, 1953

VARIAN X-BAND RADAR KLYSTRONS
feredeetee4
guaranteed specifications -- quantity prices -- assured delivery
Rugged local oscillator for mobile radar. Highly non-microphonic. Shaft tuner; no chatter or backlash; excellent for motortuned systems. Reflex, 8.5-10.0 kmc, replacing Varian V-50.

V-;80
V-270'4 V-290

For radar, beacon or low-power transmitter operation under severe mechanical punishment. Lock-nut tuner holds the tube on frequency even under shocks of several hundred g. Reflex, 8.5-10.0 kmc, replacing Varian V-51.
.00100
For high altitude or high humidity applications. Silicone-rubber-potted base and reflector connections instead of conventional base and reflector cap. Electrically identical with V-260 and V-280.

Reflex tube for test and measurement work at x-band. Integral tuner covers the full frequency range, 8.2-12.4 kmc. Typical power output is 150 mw over the band, 500 mw at center frequency.

Detailed data sheets available Write Varian Associates,
Section AA2CP, 990 Varian Street San Carlos, California

522B
ELECTRONIC COUNTER

...a small precision instrument that makes more kinds of measurements faster and more easily than any comparable device ever offered!

REVOLUTIONARY FEATURES SAVE TIME, MONEY; SPEED RESEARCH AND MANUFACTURING
Measures .00001 to 100,000 events per second Measures time 10 microseconds to 27.8 hours Accurate within 1part in 100,000 Ideal for remote measurements, monitoring Lowest cost completely versatile counter No extra-cost modification required Easily used by anyone, no training needed Reads direct in cps, kc, seconds, milliseconds Decimal point automatically indicated Displays results instantly, accurately Work-bench size; weighs just 45 pounds Unlimited uses in research, production
-hp- dependability --quality construction-- quality components
Eomplete Coverog

In an ever-increasing variety ot manufacturing and research

measurements, electronic counters provide greater speed,

higher accuracy and broader usefulness than previously avail-

able measuring equipment.

The new

522B is aversatile low-priced counter offering

you frequency, period and time interval measurement over

abroad range. The instrument is completely contained in a

small, bench-size unit, and no extra-cost modification is re-

quired to perform all functions. Results are displayed instantly

and automatically in direct-reading form. Unskilled personnel

can use the equipment immediately--no training or technical

background is needed.

WIDE RANGE Frequency range is .00001 cps to 100 kc, and the counter may be read direct from 10 cps to 100 kc. Counting is available over periods of 11000, 1 100, 1/10, 1 and 10 seconds,
or multiples of 10 seconds. Time of display can be varied at will, counts are automatically reset, and action is repetitive. For period measurement, the unknown controls the opening and closing of the gate while the instrument's decade counters record the number of cycles oían internal standard frequency. Depending on the frequency selected, the instrument reads direct in seconds and milliseconds. By this means, frequencies down to .00001 cps may be measured.
Time intervals are measured by asimilar procedure except that the gate time is controlled by a"start" and "stop" signal generated by the device under measurement or by transducers. Time intervals ranging from 10 microseconds to 100,000
seconds (27.8 hours) can be measured; and again results are

HEWLETT-PACKARD

68A

PROCEEDINGS OF THE I.R.E.

April, 1953

displayed on the panel (in seconds and milliseconds). The count may be started or stopped from common or independent sources by using either positive or negative "going" waves. The level of trigger voltage is continuously adjustable for each channel from --100 to + 100 volts.
GENERAL DESCRIPTION Model 52213 consists of live decade counters, awide range time base, and gating and auxiliary circuits applying counters and time base to the broadest possible variety of measurements. The unknown is applied to the counters through a gate circuit. This circuit remains open for aprecise interval controlled by an oven-housed quartz crystal. Stability of this crystal is at least 5, 1,000,000 per week, and may be standardized against WWV.
-hp - 522A ELECTRONIC COUNTER For applications where wide-range frequency and period measurements are desired, -hp- 522A is offered. Frequency counting facilities of this instrument are identical with -hp- 522B, except that gate time for frequency measurement is 1second or any multiple of 1second, and the standard frequency counted for period measurement is 100 kc. The automatic illuminated decimal point is omitted. -hp- 522A does not include time interval measuring circuits. $775.00 f. o. b. factory.
BRIEF SPECIFICATIONS--MODEL 522B
FREQUENCY MEASUREMENT:
Range: 10 cps to 100 kc.
Accuracy: ± 1count ± stability (5/1,000,000 per week).
Registration: 5 places. Output pulse available to actuate trigger circuit for mechanical register to increase count capacity
Input Requirements: 2 volts peak minimum. Input Impedance: Approx. 1 megohm, 50 µAdd shunt.
Gate Time: .001, .01, .1, 1, 10 seconds. Extendable to multiples of 1or 10 seconds by manual control.
Display Time. Variable .1 to 10 seconds in steps of gate time selected. Display can be held indefinitely.
PERIOD MEASUREMENT:
Range: 00001 cps to 10 kc.
Accuracy: ± .03% ± stability (for measurement over cs
10 cycle period). Gate Time: 1or 10 cycles of unknown. Extendable to any
number of cycles by manual control. (For frequencies under 50 to 60 cps). Standard Freq. Counted: I, 10, 100 cps; 1, 10, 100 kc; or external.
TIME INTERVAL MEASUREMENT:
Range: 10 µsec to 100,000 seconds (27.8) hrs.
Accuracy: ± 1/std. freq. counted ± stability. Input Requirements: 2 volts peak minimum. Input Impedance: Approx. 250,000 ohms, 50 milfd shunt. Start and Stop: Independent or common channels.
Trigger Slope: Pos, or neg. on start and/or stop channels. Trigger Amplitude: Continuously adjustable on both
channels from 100 to + 100 volts.
Standard Freq. Counted: 1, 10, 100 cps; 1, 10, 100 kc; or external.
Price: $900.00 f. o. b. factory.

IS YOUR MEASURING PROBLEM HERE?
FREQUENCY
Production quantities Nuclear radiations Power line frequencies to high accuracy R. P. S. and R. P. M. Weight, pressure, temperature and
acceleration--at remote points Very low frequencies Frequency stability Oscillator calibration Pulse repetition rates
TIME INTERVAL Elasped time between impulses Pulse lengths Camera shutter speed Projectile velocity Relay operating times Precise event timing Interval stability Frequency ratios Phase delay
The broad applicability of-hp- electronic counters makes them of greatest usefulness in any laboratory or factory. In many cases, one counter will make all your important measurements itself, and give you accuracy unavailable with other equipment. In other applications, standard transducers may be required. See your -hp- sales representative for help in applying Model 522B to your measurement problem.
ARE YOU READING THE -hp - JOURNAL?
The -bp-Journal, flow in its fourth year,
is sent to you regularly as another HewlettPackard service. It contains latest news about electronic developments, technique and instruments. Fully illustrated.
WRITE -hp- FOR YOUR FREE SUBSCRIPTION (use your Company letterhead, please)
HEWLETT-PACKARD COMPANY
2682D PAGE MILL ROAD · PALO ALTO, CALIFORNIA, U.S.A.
SALES REPRESENTATIVES IN ALL PRINCIPAL AREAS Export: FRAZAR 8. HANSEN, LTD., San Francisco ·Los Angeles ·New York

Complete Coverage

PROCEEDINGS OF THE I.R.E.

April, 1953

The biggest name in VHF-UHF lacquer...

SEND FOR NEW BOOKLET-- Complete data on Q-MAX and its outstanding advantages for RF service. Call or write for your copy now.
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70.\

PROCEEDINGS OF TIIE I.R.E.

Apra, 1953

AIT "LACQUER.

is chemically engineered to meet the specific requirements of the industry

MARLBORO, NEW JERSEY

--

Telephone: FReehold 8-1880

PROCEEDINGS OF TIIE I.R.E.

April, 1953

·REGISTERED TRADE NAME 71A

Industrial Engineering Notes

WHEN A SINGLE SCOPE WON'T DO YOUR JOB!

Try to compare four different but related phenomena ... at the

same instant ... under the same conditions ... with single channel

oscilloscopes ... and you run into trouble. Nine times out of ten,

e you'll miss those high speed signals.

There are several

oscilloscopes that lick the problem by dis-

playing four phenomena on the face of asingle 5" tube. Since their

development they have opened new fields in electronic and medical

research, strain and vibration analysis, seismography and ballistics.

Each of their four channels has independent controls for intensity, focus, and positioning of the X and Y axes. All input signals can be observed on a common time base or on separate time bases if desired. Wide band, high gain, DC or AC amplifiers are provided on both the vertical and horizontal axes.

Details about the four-channel models available as well as others with 2, 5, 6, 8, or even 10 channels are covered in our catalog. Write for your copy today.

edf0001a te9 tOrpOratiO2
1200 E. MERMAID LANE , PHILADELPHIA 18, PA .

(Continued from page 66A)
Winston-Salem, N. C., Winston-Salem Broadcasting Co., Inc., Channel 26.
Ashtabula, Ohio, WICA, Inc., Channel 15. Texarkana,Texas, KCMC, Inc., Channel 6. Longview, Texas, East Texas Television
Co., Channel 32. Hampton, Va., Peninsula Broadcasting
Corp., Channel 15. Newport News, Va., Eastern Broadcasting
Corp., Channel 33. Milwaukee, Wis., Midwest Broadcasting
Co., Channel 25. Mesa, Ariz., Harkins Broadcasting, Inc..
Channel 12. Eureka, Calif., Redwood Broadcasting Co.,
Inc., Channel 3. Rome, Ga., Coosa Valley Radio Co., Chan-
nel 9. Wichita, Kan., The C.W.C. Company,
Inc., Channel 16. New Orleans, La., Supreme Broadcasting
Co., Inc., Channel 61. North Adams, Mass., Greylock Broadcast-
ing Co., Channel 74. Portland, Me., Portland Telecasting Corp.
Channel 53. Gulfport, Miss., WGCM Television Corp.,
Channel 56. Hannibal, Mo., Courier-Post Publishing
Co., Channel 7. Minot, N. D., Rudman Television Co.,
Channel 10 and North Dakota Broadcasting Co., Inc., Channel 13. Oklahoma City, Okla., Oklahoma County Television & Broadcasting Co., Channel 25. McAllen, Texas, Texas State Network, Inc., Channel 20. Salinas, Calif., Salinas Broadcasting Corp., and Monterey Radio-Television Co., Channel 8.
The grant to Salinas Broadcasting Corp. and Monterey Radio-Television Co. was the first share-time television operation authorized by the FCC. The same Channel 8transmitter will be used by both stations on an equal-time basis and both stations will maintain their own studios in the two cities.
FCC ACTIONS
The FCC issued a Report and Order this week relaxing its operator license requirements to permit the remote control operation of certain low-power AM, FM, non-commercial FM broadcast stations. "The marked improvement and reliability of transmitter equipment" and "the successful operation by non-technical personnel of many electronic devices of acomplex nature," it was pointed out, were among the factors considered by the Commission in reaching its decision. ... The FCC recently finalized its proposed rule making of May 10, 1952, to open asection of the amateur frequency band-21,000-21,450 kc-- for the use of radio-telephony by amateurs, beginning last month. This band is allocated to amateurs in accordance with the international table of frequency allocations (Atlantic City, 1947). The radio-telephone
(Continued on page 74A)

72A

PROCEEDINGS OF TI1E I.R.E.

April, 1953

R EWC TA Aece Pt Ce up

1818

51,53

YtARS (11 111(1111(AI L e e'

PROl.R I,

L e e.

LeL

z

TRANSISTORS ...TANTALYTIC CAPACITORS

teamed in 100-milliwatt tubeless amplifier

General Electric engineers at Electronics Park, Syracuse, have developed a new tubeless audio amplifier circuit that utilizes three junction transistors and three Tantalytic capacitors.
Although still experimental, this 3-stage amplifier promises significant advances in miniaturized equipments. It has a power output of 100 milliwatts --less than 10' ;, distortion and a power gain of 70 db.
Tantalytic capacitors were a "natural" for interstage coupling in the circuit because of their small size, large capacitance and low leakage current. They match the transistors in ruggedness and long operating life. And they will operate over a wide temperature range (-- 55 °C to +85 °C with at least 65' ;capacitance at -- 55 °C). Other features include light weight, long shelf life, and hermetic sealing.
If you have a capacitor application where you need small size and superior performance, it will pay you to investigate Tantalytic capacitors. They're available in polar and non-polar construction and in

ratings from 175 muf at 5 VDC to 12 muf at 150 VDC. For additional information use the convenient coupon below.
General Electric Company, Schenectady 5, New York.

General Electric Co., Section K 407-313 Schenectady 5, New York
Gentlemen: Please send me a copy of your free Bulletin(s) Fl GEC-808 and GER-451 "Tantalytic Capacitors" Li ECG-1 "Germanium Transistors"

Name _

Company

Street
LCity

Zone

State_

GENERAL

ELECTRIC

PROCEEDINGS OF THE I.R.E.

April, 1953

73A

411w FREQUENCYTIME COUNTERS ... autoleatecaj READS FREQUENCY, TIME INTERVAL AND PERIOD

r-
USE THEM FOR
FREQUENCY MEASUREMENTS
· PERIOD MEASUREMENTS
· TIME INTERVAL MEASUREMENTS
· FREQUENCY RATIO MEASUREMENTS
· SECONDARY FREQUENCY STANDARD
· TOrALIZING COUNTER
· DIRECT RPM TACHOMETER

COMPACT DESIGN CIRCUITS FEATURES LOWER PRICES
Every known need in frequency and pulse measurement is now satisfied by four completely new designs of Potter frequency-time counting equipment.
The simplified Potter 100 KC Frequency, Models 820 and 830, are suitable for rapid and precise production line applications. The versatile Potter 100 KC and 1MC Frequency-Time Counters, Models 840 and 850, include all gating, switching, timing and counting circuitry required for any conceivable counting-type measurement.
All models feature the convenience of smaller size, lighter weight, and functional panel layout. And, optional readout indication--either the dependable Potter 1-2-4-8 decimal readout or the conventional 0-9 lamp panels--is available.
about FrequencyTime Counters-- both laboratory and industrial applications.
For further data or engineering assistance write Dept. 4-E.
115 CUTTER MILL ROAD GREAT NECK, N. Y.

Industrial Engineering Notes
page 72.9)
segment of this band is designated from 21.25 to 21.45 mc. The frequency space for Novice operation is provided at 21.1021.25 inc. The previously proposed segment for amateur F-1 (radio-teleprinter operation) has been shifted to 21.0-21.25 inc. In general, these amendments to the amateur rules (Part 12) are designed to provide maximum usefulness of the new amateur band in the interests of the various types of amateur operation, FCC reported. A request of the Maritime Mobile Amateur Radio Club to permit amateur mobile operation in the 21 amateur band outside the continental limits of the United States will be considered separately, the Commission said.. ..The FCC at present will not consider applications for FM stations contemplating a "functional service" program schedule. This was revealed in a letter released by the Commission and sent to Chicago Skyway Broadcasting Co., Inc., Chicago, applicant for an FM station there. It was pointed out that "the Commission is currently reviewing the legality and general desirability of 'Storecasting' and similar 'Functional Music' operations. Until this study is completed, the Commission is of the opinion that additional 'Storecasting' operations should not be authorized pending the resolution of the policy questions presented by such operations."
RADIATION M EASURING DEVICE
A report describing methods for proclueing better atomic radiation measuring devices was issued by the Office of Technical Services, Department of Commerce. In developing the methods, Naval Research Laboratory scientists used rapidlyrecurring, brief voltage pulse instead of a continuous high voltage on the electrodes in the Geiger tube. By not applying continuous high voltage, the scientists obtained these desirable characteristics: (I) A greater measuring range by combining continuous and pulsed voltage operation; (2) useful counter operations at higher intensity levels; (3) meter reading increases in direct proportion to the increase in radiation intensity; and (4) awider choice of filling gas. The report, "Pulsed Geiger Tube Operations" PB 111035, is available at the Office of Technical Services, U. S. Department of Commerce, Washington 25, D. C. for 50 cents per copy.
REORGANIZATION OF RTMA URGED
The RTMA Board of Directors yesterday accepted in principle recommendations of aspecial committee of the Technical Products Division calling for broad expansion and reorganization of the RadioTelevision Manufacturers Association to provide greater recognition for manufacturers in the advanced electronics field. The action climaxed a three-day industry conference in February at the Roosevelt Hotel, New York. The major recommendations of the committee were that: (1)
(Continued on page 76A)

74

PROCEEDINGS OF THE I.R.E.

April, 1953

Draw the wire-wound control curve

you need: Clarostat winds the "card" to

match it. Specify tolerances: Clarostat meets

them. Order any quantity: Clarostat delivers piece after piece, always uniform, always

WS,

dependable, always economical.

All because Clarostat-designed and built winding machines, manned by skilled winding specialists, handle any kind and size of wire on any kind and shape support. Intricate

control curves are met with tapered or notched supporting strips, by variable spacing of turns, by different wire sizes. From 0.032" down to 0.0009" dia, and finer, Clarostat winds

to your precise requirements.

?PT 14//
err eSe

Send us that control spec, regardless how "special". Our engineering collaboration, quotations and delivery schedules, are yours for the asking.
ROSTAT Controls 8t Resistors
CLAROSTAT MFG. CO., INC., DOVER, NEW HAMPSHIRE In .Conacict Canadian Marconi Co., Ltd., Toronto, Ontario

PROCEEDINGS OF THE I.R.E.

April. 1953

75A

ge©12© MOUNTINGS PROTECT INSTRUMENTS aerd ELECTRONIC EQUIPMENT
east VIBRATION a-etee SHOCK DAMAGE ···

LIi..)BRATION and shock are natural enemies--of electronic equipment and precision instruments .. .To control the---c1-a-m-a- ge which these enemies can do, Lord Vibration Control Mountings
and Bonded Rubber Parts are used to very profitable advantage. More than aquarter century's experience in dealing with vibration and shock is yours when you take advantage of Lord engi-
neering assistance. The result of such consultation is full protection for electronic units and sensitive instruments by correctly designed and precisely manufactured Lord Mountings and Bonded-Rubber parts.

BURBANK, CALIFORNIA 233 South Third Street

DALLAS, TEXAS PHILADELPHIA 7, PENNSYLVANIA DAYTON 2, OHIO

413 Fidelity Union Life Building

725 Widener Building

410 West First Street

DETROIT 2, MICHIGAN NEW YORK 16, NEW YORK CHICAGO 11, ILLINOIS 7310 Woodward Ave. 280 Madison Avenue 520 N. Michigan Ave.

CLEVELAND 15. OHIO
Room 811, Hanna Bldg.

LORD MANUFACTURING COMPANY ·ERIE, PA.

adgua rteeIT tbr
VIBRATION CONTROL j

Industrial Engineering Notes
(Continued from page 74A)
RTMA change its name to the Electronics Manufacturers Association, or some similar name; (2) adivision for manufacturers of advanced electronics products be established within the Association, and (3) the Engineering Department be expanded and technical products in the military and commercial sales areas.... Formation of an engineering committee on Internation Components Standards under the Chairmanship of Leon Podolsky, of Sprague Electric Co., was announced recently by Dr. W. R. G. Baker, Director of the RTMA Engineering Department. The function of this new Committee is to recommend material for international standardization and to review proposals on components submitted by Technical Committee 12-3 of the
Internation Electrotechnical Commission.
The Committee also will give guidance to the RTMA representative on the IEC. Other members of the Committee are: R. J. Biele, General Electric Co.; Jesse Marsten, Internation Resistance Co.; J. D. Heibel, Erie Resistor Corp.; J. W. Maxwell, P. R. Mallory & Co., Inc.; J. D. Stacy, General Electric Co.; and Fred G. Weber, F. W. Sickles Division.
M AT ERIALS
Interior Secretary Douglas McKay announced recently that the Bureau of Mines in the Pittsburgh region has started research to find additional sources of germanium for use in radar and other electronic equipment of the Armed Forces. The project is being conducted at the request of and in co-operation with the Signal Corps Engineering Laboratories, Fort Monmouth, N. J. A good method to obtain germanium is to extract it from the ash resulting from the burning of coal; hence, the search is being concentrated in ash pits and smoke stacks of large industrial coal consumers, the Bureau reported. Chemists with the Bureau also plan to make studies of gas producers and blast furnaces as possible sources of germanium. Germanium is now produced in small quantities as abyproduct of zinc refining. Annual output is only 6,000 pounds, it was pointed out.
NEW CRYSTAL OSCILLATOR
As part of its program devoted to the improvement of measuring and calibrating standards, the National Bureau of Standards recently developed acrystal oscillator that is small, portable, dependable and accurate over long periods of time. The new oscillator unit was developed by Peter G. Sulzer of the NBS staff. This new crystal oscillator utilizes a junction transistor as the source of driving power for ahigh-stability quartz crystal unit. All components of the circuit, including the power supply, fit into a metal tube less than 2 inches in diameter and about 7inches long. With the device it becomes possible to make available a readily-portable, continuously-oscillating frequency standard that may be carried to all parts of the world, NBS re-
(Continued on page 78A)

PROCEEDINGS OF THE I.R.E.

April, 1953

BULLETIN 960

If

ne

HMO

Super-rugged...absolutely rigid and practica ly indestructible

An ellrill1IV*

edvanrwl enipneer ng

deselopment

Compressors Seals

are produced hy acesclusty.. pew wheretn the glass remains under cunstset

cratipretwun and is thereby extremely

strong and difficult In put under wren

The tryott es a

and vastly greater

resistance t«. yhock and vibration

All traders are wlecorte treated for sted

Super dependable... 56 standard types available!
Another example of E-I advanced engieering, these multiple headers are prouced under an exclusive E-I process. By radically new process the glass, sealed nder tremendous compression, is exremely strong and difficult to put uncle,
stress. This results in a new, far greater resistance to shock and vibration. E-I
ompression Seals are silicone treated for maximum immunity to humidity, tin !dipped for easy soldering and guaranteed
acuum tight. New Bulletin 960 completely describes E-I Compression Type Multiple Headers. Call
rwrite for your opy, now!

Expo

Is

PHILIPS

EXPORT CORP.

100 East 42nd Street

New York 17, N. Y.

E-I ... your
reliable source for all hermetically sealed terminals--
Hundreds of standard types of multiple headers, octal plug-ins, terminals, color-coded terminals, and end seals for electronic an electrical requirements.

·The devices shown in this bulletin or. cov·red by patents pending and

ELECTRICAL INDUSTRIES

DIVISION OF

OR

44 SUMMER AVENUE

.NEWARK 4, NEW JERSEY

ULM 1A OENg UO3 ARE BASIC
in current electronic trend

Industrial Engineering Notes
(Continued from Page 76/1)
ported. Complete details on the precision transistor oscillator will appear in a future NBS Technical Bulletin.

\

4 60

58

2 62

ZI

16

2052

64

· Premium Performan ce

and tale · Minimum

Space

pet

Mid.

· Wide 'temperature limits

· Infinite Shell life · Proven Reliability
Since 1930

ELECTRONIC FLOWMETER
A new type of electronic flowmeter, capable of measuring the air currents in a still room or the rapid flow of fluids in pipes, has recently been developed at the National Bureau of Standards. It was designed by Henry P. Kalmus of the NBS staff. This new device utilizes the change in velocity of sound waves as a measure of fluid flow. It has avery fast response and does not obstruct the fluid currents to make the measurement. In addition, the signal-to-noise ratio is sufficiently high to permit the measurement of extremely small velocities. Complete details on the electronic flowmeter appeared in the NBS Technical News Bulletin for February.

TANTALUM CAPACITORS

Now, through the use of tantalum, new high standards

of electrolytic capacitor performance are available. The

tantalum oxide film is the most stable dielectric, chemi-

cally and electrically, yet discovered. As a result, Tan-

talum Capacitors offer advantages not found in any other

electrolytic type--long life, space saving, wide temperature

range, excellent frequency characteristics, no shelf aging.

Tantalum Capacitors are made by Fansteel and other leading capacitor man-

tullslet I

ufacturers. Ask for current information bul-

letins on Fansteel Tantalum Capacitors.

FANSTEEL METALLURGICAL CORPORATION
NORTH CHICAGO, ILLINOIS, U. S. A. Tantalum Capacitors...Dependable Since 1930

32401C

CIRCUITRY "PACKAGES"
The National Bureau of Standards has recently developed an improved system of standardized plug-in circuitry "packages" for use in the construction of electronic equipment. This NBS system reportedly is an extension of similar improvements under development by industry. Each new circuit package has alarge number of connections brought out to connector pins. A test jack at the top of each package helps locate defective units, making it easy to replace trouble-causing with trouble-free packages. A distinctive feature is the general similarity of most of the circuit stages. A single basic tube circuit is adapted to the great majority of requirements, and the same basic circuit serves as a low-impedance pulse driver, as a flip-flop, and for a number of gating functions. These rapidly repleaceable units, if adopted by manufacturers, promise to combine reduced manufacture and repair costs with improved reliability, the Bureau said. Complete details of the new circuit packages appeared in the NBS Technical News Bulletin for March.
M OBILIZATION
With the view of bridging any gaps which may exist between industry and government, the U. S. Department of the Navy recently sponsored asymposium on electron tube reliability. The one-day session was held February 12 in the Department of Commerce Auditorium, Washington. The program included discussions on the following topics: Design Features of Reliable Tubes, R. E. Moe; Production Aspects of Reliable Tubes, L. B. Davis; and Quality Control Procedures for Reliable Tubes, J. A. Davies, all of the General Electric Co. Specifications for Reliable Tubes, A. J. Heitner; Missile Tube Applications, P. R. Erdle, both of Sylvania Electric Products, Inc. Determining Tube
(Continued on page 80A)

78A

PROCEEDINGS OF THE I.R.E.

April, 1953

Unexcelled for Accuracy and Dependability The COLLINS 51J
Communications Receiver

Your inquiries will receive prompt attention

The Collins 51J Communications Receiver in addition to its outstanding performance in the communications field, is being widely used in industrial laboratories as a sensitive and accurate measuring instrument. Write today for complete details and specifications.
Condensed Specifications
FREQUENCY RANGE: .54 to 30.5 megacycles.
CIRCUIT: Double Conversion Superheterodyne.
CALIBRATION: Direct reading in megacycles and kilocycles. One turn of main tuning dial covers WO kilocycles on all bands. TUNING: Linear, divided into 30 one-megacycle bands. Each dial division represents one kc. FREQUENCY STABILITY: Overall stability within
kt under normal operating conditions.
SELECTIVITY: 5.5 to 6.5 kilocycles at 6 db down. 17 to 20 kilocycles at 60 db down.
AUDIO OUTPUT: 4 and 600 ohms impedance. 11 /2 watts at 1000 cps with less than 15% distortion overall. "S" meter may be switched to read audio output. RF INPUT: High impedance single-ended. Breakin relay mounted internally. Antenna trimmer will resonate input circuit when used with any normal antenna. POWER REQUIREMENTS: 85 watts 45/70 cps, 115
volts or 2ill soils.
DIMENSIONS: Panel -- 10 1 /2 inches high, 19 inches wide, notched for rack mounting. Optional metal cabinet -- 21-1/8 inches wide, 12-1/4 inches high and 13-1/8 inches deep. Speaker available in metal cabinet 15 inches wide, 105/8 inches high and 9-1/8 inches deep.

COLLINS RADIO COMPANY Cedar Rapids, Iowa

PROCEEDINGS OF THE I.R.E.

April, 1953

79a

(et;

Quality Engineered for lasting Performance ...
Durability and good performance are qualities that begin with and are largely dependant on good engineering. Amphenol's entire engineering staff is dedicated to the goal of unsurpassable quality. To accomplish this goal, Amphenol has gathered a staff of engineers whose combined experience covers every phase of electrical and electronic applications. This vast background is continuously being extended by an unceasing program of research and development.
Amphenol's methods and production engineers further this devotion to quality by insisting that production methods and machines accurately produce finished products that match the quality of the original design.

------- s-m-aramaggimgammeeàieieer

AMERICAN PHENOLIC CORPORATION chicago 50, iliinois

Industrial Engineering Notes
(Continued from page 784)
Reliability in Operational Equipments, E. F. Jahr; and Statistical Aspects of Tube Reliability, G. R. Herd, of Aeronautical Radio Inc. ...The outlay for scientific research and development totaled more than $3.5 billion in 1952, of which almost half was financed by the government, according to a report prepared jointly by the Bureau of Labor Statistics and the Research and Development Board of the Defense Department. The report, based on a nationwide survey of 2,000 companies and covering some 85 per cent of the total industrial research in 1951, aimed at finding out what industry was doing in the field of research and development. The companies responding to the RDB survey accounted for almost $2 billion of research, with electronics accounting for 27.3 per cent of this amount, or around $500 million. Some 94,000 research engineers and scientists were employed in January 1952 by companies replying to the RDB survey, and 23.2 per cent of them were in the field of electronics. The average research cost per research employee, including both professional and non-professional worker, was $8,900 in 1951. Copies of "Industrial Research and Development" can be had by writing to the Research and Development Board, Department of Defense, Washington 25. D. C.
RESEARCH
The Office of Technical Services. Department of Commerce, has announced the release of its January Bibliograph of Technical Reports. The monthly publication, which lists available reports on scientific and technical research done by the government or with government aid, includes the following of interest to the electronics industry: "Improved Magnetic Materials" (PB 107813), available from the Photoduplication Section, Library of Congress, for $2.75 in microfilm and $7.50 in photostat form. "Improved Magnetic Materials" (PB 107815), Photoduplication Section, Library of Congress, for $2.50 in microfilm and $6.25 in photostat form. "Investigations of Methods of Increasing Life and Capacity of Lead Acid Storage Batteries. I. Preliminary Study of Methods for Evaluating the Corrosion Resistance of Positive Grid Materials" (PB 107841), Photoduplication Section, Library of Congress, Microfilm, $3.75, photostat, $11.25. "Simplified Methods for the Evaluation of Transients in Linear Systems," (PB 107950), Photoduplication Section, Library of Congress, microfilm $2.25, photostat, $5.00. "Television Recording Project" (PB 111072), available from the Office of Technical Services, Department of Commerce, Washington 25, D. C. for $1.00.

AKRON
Student paper competition; January 13, 1953. "Future Prospects of Ultrahigh Frequency Television," by Dr. Wen Yuan Pan, Radio Corporation of America; January 20, 1953.
ATLANTA
"Communications in Civil Defense." by Stark Totman, Federal Civil Defense Administration; election of officers; January 23. 1953.
BALTIMORE
"Ultrasonics," by Dr. Patrick Conley. Westinghouse Electric Corporation; January 14, 1953.
"Space Travel, When?" by Dr. Wernher von Braun, Ordnance Guidance Missile Center. Huntsville, Ala.; February 12, 1953.
BOSTON
"The Modern Flight Simulator," by W. W. Wood, Jr., Link Aviation. Inc., and "An Automatic Ground Controlled Approach System," by R. C. Kelner; November 20, 1953.
"Physics of Transistor Electronics," by Dr. W. H. Brattain, Bell Telephone Laboratories and "Problems in the Fabrication of Point Contact Transistors," by R. S. Follows, Sylvania Electric Products, Inc." December 18, 1953.
"A Wide-Range Pulse Generator for Laboratory Applications." by R. W. Frank, General Radio Company, and "Basic Systems for the Measurement and Generation of Phase Relationships." by J. C. Looney, Technology Instrument Corporation; January 22. 1953.
BUFFALO-NIAGARA
"Minaturized Components and Their Applications in Transistor Electronics," by P. S. Darnell, Bell Telephone Laboratories; January 21, 1953.
CENTRAL FLORIDA
"A Novel Electronic Multiplexing System," by P. M. G. Toulon, Radiation, Inc.; November 20. 1952.
"Electric Amplifiers," by Dr. H. E. Hollman, Naval Air Missile Test Center; December 17, 1952.
CHICAGO
"A Review of Transistor Progress in 1952," by R. F. Shea. General Electric Company; January 16, 1953.
CLEVELAND
"The Present Status of Transistor Development," by J. A. Morton, Bell Telephone Laboratories; January 15, 1953.
COLUMBUS
"Advantages and Disadvantages of Big and Small Business," by G. Foster. Industrial Nucleonics; L. Moore. Columbus and Southern Electric Co.; R. W. Masters. The Ohio State University and J. Audi, Line Material Co.; January 13, 1953.
CONNECTICUT VALLEY
"The Problem of High Fidelity Audio Reproduction in the Home," by Dr. L. L. Beranek. Massachusetts Institute of Technology; January 15. 1953.
DALLAS-FT. WORTH
"Switching Circuits for Automatic Control." by William Keister, Bell Telephone Laboratories; February 11, 1953.
DAYTON
"Servomechanisms," by Donald McDonald, Cook Research Corp.; February 12, 1953,
DES MOINES-AMES
"Highlights and Sidelights of Engineering," by C. A. Scarlott, Editor of "Westinghouse Engineer"; January 27. 1953.
(Continued on page 82A)

.. ELECTRONIC COMPONENTS
BY AMPHENOL
r _,····ici-·
The over 9,000 cataloged items manufactured by Amphenol are meant to answer every type of application problem. If your problem is so new or unusual that none of the general types listed below meet your requirements, then consult with Amphenol's engineers for the special component you need.
RACK & PANEL TYPE CONNECTORS
AN TYPE CONNECTORS RF TYPE CONNECTORS AUDIO CONNECTORS POWER PLUGS BLUE RIBBON CONNECTORS INDUSTRIAL SOCKETS MINIATURE SOCKETS TUBE SOCKETS &
RADIO COMPONENTS MICROPHONE CONNECTORS RG COAXIAL CABLES,
TEFLON & POLYETHYLENE CABLE & WIRE ASSEMBLIES PLASTICS- EXTRUDED
& INJECTION MOLDED Write today for your copy of General Catalog B-2
AMERICAN PHENOLIC CORPORATION chicago 50, Illinois

77.77,,re`..:7-777
4

DIRM

WHIÇH PILOT LIGHT
DO
YOU
NEED?

YOUR FrietW

THE BIG ONE

This Pilot Light Assembly was first made to accommodate the S-11 lamp and was intended for use in the cabs of great diesel locomotives.
THE LITTLE ONE

'or

The miniaturization program on defense products required the development of this sub-miniature light. It is used on communication equipment and aircraft. Midget flanged base
bulbs to fit are rated 1.3, 6, 12, and 28 volts.

Dialco HAS THE COMPLETE LINE of INDICATOR and PANEL LIGHTS
to suit your own special conditions and requirements will be sent promptly and without cost. Just outline your needs. Let our engineering department assist in selecting the right lamp
and the best pilot light for YOU.
Write for the Dialco HANDBOOK of PILOT LIGHTS

WEAL SIZE
Cat. #613529-211
ACTUAL SIZE
Cot. #8-1930-621

Foremost Manufacturer of Pilot Lights
DIALIGHT CORPORATION

60 STEWART AVENUE, BROOKLYN 37, N. Y.

HYACINTH 7-7600

82.

(Continued from page 8IA)

FT. WAYNE

"Advance Study and Your Engineering Future," by C. J. Poling, Purdue University; Feb-
ruary 5. 1953. HAMILTON

·A Color TV Receiver for N.T.S.C. System," by K. Farr. Westinghouse Electric Corporation;

January 26. 1953.

"VHF and UHF Measurement Techniques." by

W. A. Cumming. National Research Council; Feb-

ruary 16, 1953.

INYOKERN

«Frequency Meter Design Techniques," by Leonard Cutler. Gertch Products, lac.; January 27.
1953. KANSAS CITY

"Aurora Magnetic Storms and Radiation." by Dr. R. K. Moore, Sandia Corp.; January 20, 1953.
"Telemetering-Instruments. Systems. Techniques," by M. V. Kieber, Jr., Bendix Aviation Corp.; February 10. 1953.

Limn ROCK
«Transistor Manufacturing Techniques," by A. D. Evans, Texas Instrument Co.; January 22, 1953.
"Binaural Recording and Reproduction Sound." by C. G. Barker. Magnecord, Inc.; February 10. 1953.
LONDON
·A Synopsis of Tape Recording Systems and Standards," by G. Robitaille, Chief Engineer. Radio C.F.P.L.; January 20, 1953.

LOS ANGELES
"Remote Recording of Brain Potentials." by Dr. J. A. Gengerelli, Faculty. University of California at Los Angeles; February 3. 1953.

Louisvivat
"Application of Radio Isotopes to Medical Research and Therapy." by Drs. M. I. Schwalbe and Morris Nataro; February 12, 1953.

MILWAUKEE
"Pickups and Pre Amps," by N. C. Pickering. Pickering Corp.; January 23, 1953.
"Design of Switching Circuits for Automatic Control," by S. H. Washburn, Bell Telephone Laboratories; February 4, 1953.

MONTREAL
"Modern Glasses and Their Applications." by Dr. W. W. Shaver. Corning Glass Works; November 12. 1952.
"High Fidelity Audio Reproduction," by Dr. J. T. Henderson, Regional Director of Region 8, and R. H. Tanner. Northern Electric Company; December 10. 1952.
NEW YORK
"Recent Industrial Applications of Magnetic Amplifiers." by V. H. Krummenacher. Bogue Electric Manufacturing Company; January 7. 1953.

NORTH CAROLINA-VIRGINIA

"The Next Era in Electronics." by Dr. I. G.

Wolff, Radio Corporation of America; January 30.

1953.

OKLAHOMA CITY

"Theory and Application of Transistors," by O. K. Garriott, Student. Oklahoma University; January 13. 1953.
OMAHA-LINCOLN

"New Facilities Now Being Installed in New
Building of Lincoln Telephone and Telegraph Company," by C. C. Donley, Lincoln Telephone and Telegraph Company; January 26, 1953.
(Continued on page 84A)

PROCEEDINGS OF THE I.R.E.

April, 1953

Here's how to get
GOOD USABLE POWER AT UHF

Sylvania Rocket Tube Type 2C37 supplies 450 Mw at 3300 Mc.
Because of their high power throughout the UHF spectrum, Sylvania rocket tubes are especially recommended for service as pulsed oscillators, cw oscillators, rf amplifiers and frequency multipliers ... this is one more reason why it will pay you to specify SYLVANIA.
Compare Sylvania Rocket Tube's Performance

Typical UHF Triode Performance
Power Vs Frequency (For Sylvania Rocket Tube Type 2C37'
900

800
e 700

TUBE "A" "c'Y LVANIA C37 Rocet

=.1 600

4ye

500

ruin ,. c.,,

a. 400

ODE

o 300
o
200

100

1000

1500

2000

2500

FREQUENCY MEGACYCLES

3000

3500

SYLVANIA

ELECTRONIC DEVICES; RADIO TUBES; TELEVISION PICTURE TUBES; ELECTRONIC TEST
EQUIPMENT; FLUORESCENT TUBES, FIXTURES, SIGN TUBING, WIRING DEVICES; LIGHT BULBS; PHOTOLAMPS; TELEVISION SETS

PROCEEDINGS OF TIIE 1.2.E.

April, 1953

SYLVANIA ROCKET TUBE
TYPE 2C37

Sylvania Electric Products Inc. l)ept. 3E-1501, 1740 Broadway, N.Y. 19, N.Y.
Please send me latest data sheets concerning Sylvania Rocket Tubes

City

Zone

Mate

83 \

PROOF of PERFORMANCE

Shure slender Gradient' Microphones solve difficult acoustic problem

(Continued from page 824)
PHILADELPHIA
'The Human Centrifuge, by T. F. Pierce and C. E. Brooks. Aviation Medical Acceleration Laboratory, Naval Air Development Center; November 6, 1952.
"Field Emission Microscopy," by Dr. E. A. Muller, Faculty, Pennsylvania State College; January 8. 1953.
"Principles and Applications of Magnetic Amplifiers," by Dr. H. L. Goldstein. Bell Telephone Laboratories; February 4. 1953.

PITTSBURGH
'Generalized Servomechanism Evaluation." by %V. M. Kaufman, Student, Carnegie Institute of Technology; February 9, 1953.

SAN FRANCISCO
"Electronics in the Oil Industry," by D. J. Pompeo, Shell Development Company; E. E. Harison, Standard Oil of California; V. N. Smith, Shell Development Co. and Dr. D. Hull, California Research Corp. Moderator, O. J. M. Smith. January 14, 1953.
SYRACUSE
'Solid State Luminescence," by Dr. Williams, General Electric Company; February 5. 1953.

TOLEDO
"Single-Sideband Transmission by Envelope Elimination and Restoration," by L. R. Kahn, consulting firm; February 12. 1953.

TORONTO
"High Efficiency TV Horizontal Sweep Systems" and "Dissipation Determination," by C. E. Torsch, General Electric Company; January 26. 1953.
TULSA
"Electronics in Aviation." by W. J. Weldon, American Airlines, Inc.; January 21, 1953.

VANCOUVER
Student's Night. Speakers: H. J. Goldie, B. P. Hildebrand and H. Palmer, Students, University of British Columbia; January 19. 1953.

"315"
GENERAL PURPOSE List Price
$1500

'f 3"
BROADCAST
list Price
$125 00

III

11116-.

Former Governor Stevenson of Illinois, pictured as he addressed Detroit audience on Labor Day, during the 1952

presidential campaign.

SA,,,? Pate. Pendenn

SHURE BROTHERS, Inc. * Microphones and Acoustic Devices

225 West Huron Street, Chicago 10, Illinois

Cable Address: SHUREMICRO

W ASHINGTON
"Microwave Propagation on Dielectric Rods in Ferromagnetic Media." by A. G. Fox. Bell Telephone Laboratories. Inc. and "A New Transistor for High Frequency Use." by R. I. Wallace, Bell Telephone Laboratories, Inc.; January IS, 1953.
"The Transmission of Speech by Narrow Band Signals." by W. G. Tuller and H. M. Williams. Melpar, Inc.; February 9, 1953.
W ILL1 AMS PORT "The Design of Receiving Tubes for Use in UHF TV Service." by L. R. Maguire and R. W. Slinkman and E. H. Boden, Sylvania Electric Products Inc.; January 28, 1953.
SUBSECTIONS
LANCASTER "Practical Television Antennas for Ultra-High Frequency Reception." by E. O. Johnson. RCA. Victor; January 14, 1953.
LONG ISLAND "Low Temperature Physics," by Dr. C. A. Swenson, Massachusetts Institute of Technology; January 13, 1953.
NORTHERN NEW JERSEY "Theseus. A Maze-Solving Machine." by Dr. Claude Shannon, Bell Telephone Laboratories. Inc.; January 14, 1953.
(Continued on Page 864)

PROCEEDINGS OF THE I.R.E.

April, 1953

electrostatically focused Picture Tubes take the full design center max. rating of 18,000 volts with adequate "high line" reserve.

Tested At 22,000 Volts

Long Life Guns

No Voltage Breakdown

Long Life Screens

Superior 100(ii Area Focusing

RAYTHEON MANUFACTURING COMPANY '

ure/h-pire *el "h'ellelIiiee

7.4·wton, Moss Bigelow. 4 7500 · Chicago, III N

RAYTHEON MAKES ALL THESE: .

3-4980 · Los Angeles, Calif . Richmond 7.3524 · MICROWAVE TUBES · RECEIVINC ANN PICTURE TONES

PROCEEDINGS OF THE I.R.E.

April, 1953

(Continued from page 81A)
Paco ALTO
"Basic Concepts of Information Theory." by Dr. B. M. Oliver. Hewlett-Packard Company; January 20. 1953.
Roma
"Miniaturization of Electronic Equipment." by Gustave Shapiro. National Bureau of Standards; January 19. 1953.
W INNIPEG
"Technical Aspects of TV," by J. E. Hayes. C.B.C.; December 4, 1952.

WHEN TEMPERATURES RUN HIGH
In the design of electrical and electronic circuits where operating temperatures run fairly high, it is extremely important that the voltage ratings of components such as capacitors conform exactly to name-plate designations.
P-C Capacitors, designed for temperatures ranging from minus 90° C. to plus 200° C., depending upon the type, are guaranteed to operate without voltage derating at temperatures specified.
You can design your circuits around P-C Capacitors with complete assurance of their performance at specified temperatures.

P-C CAPACITORS OFFER YOU

Smaller Size

Lighter Weight

Higher Temperatures

High Resistance

Low Absorption Extreme Voltage Range Maximum Capacitance
Stability

Low Power Factor
High Current Ratings
Higher Frequency of Resonance

Your inquiries invited. Ask for complete catalog on your company letterhead.
Plastic Cctpacítors, Inc.
Plastic Film Capacitors · High Voltage Power Packs · Pulse Forming Networks
2511 W. Moffat St., Chicago 47, Illinois

At.RICUL'IrRAL & M ECHANICAL COLLEGE OF TEXAS. IRE-ALEE BRANCH
"Can Machines Think?" By Mr. Keister. Bell Telephone Laboratories; February 9. 1953.
UNIVERSITY OF AKRON. IRE-MEE BRANCH
Student Papers: "A Two Speed Synchronous Motor and Its Controls." by Curtis Ivey. «Power Factor Meter." by Raymond Miller, and «A.M. Detector." by Robert Savoy, Students. University of Akron; January 13. 1953.
UNIVERSITY OF ALBERTA. IRE-AIEE BRANCH
"Telephone Connections in Alberta." by Mr. Schmidt, Alberta Research Council; January 19. 1953.
"Industrial Welding." by T. J. Jacobs. Jacobs Welding Engineering School; February 2. 1953.
BRITISH COLUMBIA, IRE-AIEE BRANCH
General Meeting; February 6. 1953.
BROWN UNIVERSITY. ¡RE-ALEE BRANCH
General Business Meeting; December 9, 1953. Field Trip to WPRO-Providence; February 5, 1953. Film. "Radio Frequency Heating"; February 18. 1953.
CALIFORNIA STATE POLYTECHNIC COLLEGE. IRE BRANCH
"The Fundamentals of Transistors and their Applications," by Walter Sterling, ConsolidatedVultee Aircraft Company; January 14, 1953.
UNIVERSITY OF D ENVER, IRE-AIEE BRANCII
General Meeting; February 5, 1953.
STATE UNIVERSITY OF IOWA. IRE BRANCH
Films, "Navy and National Bureau of Standards Research and Development Laboratories of California" and "United States Naval Ordinance Test Station--lnyokern"; November 5. 1952.
Open Discussion on "Seminar Field Trips"; November 12, 1952.
«Underground Transmission Power Cables." by W. J. Anciaux and "380 KV Overhead Transmission System of Sweden," by E. H. Berentsen. both students. University of Iowa; November 19. 1952.
«SUI Radio Amateur Club.' by J. E. Frankhauser. Faculty. State University of Iowa; December 3, 1952.
"Work Experiences at Collins Radio Co." by W. J. Streib. Faculty. State University of Iowa; December 17, 1952.
(Continued on gage 90A)

PROCEEDINGS OF THE I.R.E.

April, 1953

ejAyi edie EEN ROOM GUIDE!
Ask for
ACE Bulletin 3

RELAYS
Our stock of more than a million relays -- in over a thousand different types -- is the world's largest. Don't delay your production for want of large or small quantities of relays of any type. Telephone, wire or write for quotations.

NEW AND MORE COMPREHENSIVE

1953
RELAY SALES CATALOG

/-e.,
er-'

41;j

NOW READY

Be sure to send for your copy

Telephom.
SEeley 8-4146

I

I

71154311% :j i

·

Nine out of 10 screen rooms

used in meeting today's exact-

ing specifications were made

by ACE!

These sturdy shielded enclos-

ures provide aGUARANTEED attenuation of 100 db from 0.15 to 1,000 mega-

cycles and to closely approach this atten-

uation at 10,000 mc. They are ideally suited for keeping "background" radio interference influence from affecting sen-

sitive R-F measurements or for shielding

equipment that would otherwise cause

serious radio broadcast or TV noise.

Features include low R-F impedance

door design; complete facilities for power, water, gas, air conditioning or ventilation service entries; access doors;

"cell type", single screen or solid shield and many others.

Installed in afew hours!
Ace rooms are supplied in pre-built sectional form for quick, easy erection. They can readily be enlarged or relocated.

MEET EXACTING SPECIFICATIONS INCLUDING JAN -I-225, 16E4 (SHIPS), MIL-1-6181 AND OTHERS WITH AN ACE SHIELDED ENCLOSURE!

833 W. CHICAGO AVE.,
DEPT. 7, CH ICAGO 22. ILL.

PROCEEDING. OF THE I.R.E.

April, 1953 ·

3644 N. Lawrence St Philodelphio 40, Po.. Tralephone: REgent 9.1019
87.`

MAKINGS OF A MISSILE I
...1.111111L
Many things go into the Makings of a Missile... electronic tubes, rocket motors, metals, plastics and
creative engineering talent running the whole gamut of the engineering specialties. Fairchild's Guided Missiles
Division has this engineering talent--welded into a team by experience going back into World War II when 'Fairchild was prime contractor for one of the
earliest guided missiles. For its experienced missile engineering and production organization, which has
produced missiles for all three branches of the Armed Services, Fairchild recently completed this
country's first privately built plant devoted exclusively to missile development and production.
IF ENGINE AND AIRPLANE CORPORATION AIRCHILD
Gaiezw/fretefeed VVyandcinch, L. I., N. Y. Other Divisions: Aircraft Division, Hagerstown, Md. Engine Division, Farmingdale, N. Y.

Rim eximialimmafgfleiïsit--Àî_mukisamm--àitàiàaiei»L-

PROCEEDINGS OF THE I.R.E.

April, 1953

Another new member of the CLEVELITE family

1orkrzte Tubing in foreground, enlarged to show detail
TORKRITE ... Clevelite EE Internally Threaded and Embossed Tubing ELIMINATES TORQUE AND STRIPPING PROBLEMS!

A few of many ADVANTAGES:
TORKRITE'S re-cycling ability is unmatched. After amaximum diameter core has been re-cycled in a given form a reasonable number of times, a minimum diameter core can be inserted and measured at I" oz. approx.
TORKRITE has no hole nor perforations through the tube wall. This eliminates possibility of cement leakage locking the cores.
TORKRITE allows use of lower torque as it is completely independent of stripping pressure.
With TORKRITE torque does not increase after winding, as the heavier wall will not tend to collapse and bind the core.
Available in lengths 3/4" to 31/8" to fit a 1/4-28 core.
** *

Electronic engineers find that TORKRITE, this newly designed and constructed Coil Form, has definite advantages over all other types requiring the use of threaded cores.
TORKRITE is one of the many items of CLEVELITE ... acomplete line of tubing for coil forms, collars, bushings, spacers, tubes and other items.
CLEVELITE has long been giving continuous satisfaction because of its dependable performance, uniformity and close tolerances.
Consult our Research and Engineering Laboratory. It is at your service.

WHY PAY MORE? FOR THE BEST ...CALL CLEVELAND!
·Reg. U S Pat. Off.

('CLEVELAND CONTAINERe

6201 BARBERTON AVE.

CLEVELAND 2, OHIO

PLANTS AND SALES OFFICES at Plymouth, Wis< ,Chkago, Detroit, Ogdensburg, N.Y ,larnesburg, ABRASIVE DIVISION at Cleveland, Ohio
CANADIAN PLANT: The Clevelond Container, Conodo, Ltd ,Prescott, Ontorio

REPRESENTATIVES NEW YORK AREA R. T. MURRAY, 604 CENTRAL AVE., EAST ORANGE, N.J. NEW ENGLAND R. S. PETTIGREW CO., 62 LA SALLE RD, WEST HARTFORD, CONN CHICAGO AREA PLASTIC TUBING SALES, 5215 N. RAVENSWOOD AVE., CHICAGO

PROCEEDINGS OF THE IRE.

Aptil, 19.53

89.

STUDENT

( ,

BRANCH
MEETINGS

(Continued from rage 86.-1)

· If performance and long life are the primary factors in your application of transformers, then submit your specifications to Acme Electric. Quality comes first in every Acme Electric transformer.

ACME ELECTRIC CORPORATION

444 WATER STREET · CUBA, N.Y.

In Canada: ACME ELECTRIC CO RP. LTD.

50 North Lino Rd.

Toronto. Ont.. Canada

Aem2&fe'LtEizetr ete T it A NSF OR MEGt

TYPE 4200

e enee

ll e

This unit has been developed to meet present day requirements for compactness. The filter requires only 31 /2 inches of rack space.

-· · _ -· ·

Features ...

· LOW HUM PICKUP through the use of torold coils. The unit may be used in circuits having signal levels as low as -40 dbm without the necessity for taking special precautions against hum pickup.
· LOW DISTORTION: The filter may be used at levels up to plus 20 dbm with negligible intermodulation distortion.
· RELIABILITY: All capacitors and inductors are hermetically sealed for lifetime service. Aging effects are negligible.
General Specifications ...

DIMENSIONS: Standard rack panel, slotted, 3I/2" high. Maximum depth 7½".

CONTROLS:

Low frequency cutoff selector knob, high frequency cutoff selector knob, on·off key.

RANGES:

Both low and high frequency cutoff controls cover 100, 250, 500, 1000, 2000, 3000,

4000 and 5000 cycles.

ATTENUATION: Approximately 16 db, per octave on both high and low frequency cutoff points.

IMPEDANCE: 500/600 ohms, in-out.

FINISH:

Engraved panel finished In medium gray baked enamel. (Special colors available upon request.)

The filter has standard input and output jacks located on

the front panel in addition to the terminal block at the rear.

11423 VANOWEN ST., NORTH HOLLYWOOD, CALIFORNIA

SUnset 31860

Manufacturers of Precision Resistors, Toroid Inductors and Electric Waco Filters

REPRESENTATIVES: Jack Beebe, 5707 W. Lake Street, Chicago, Illinois George E. Harris & Co., Box 3005, Municipal Airport, Wichita, Kansas Marvin E. Nulsen, 5376 E. Washington St., Indianapolis 19, Indiana Burlingame Associates, 103 Lafayette Street, New York City

·

For further information contact your nearest Hycor representative or
write for Bulletin S

"Direct Projection Television." by D. W. Thomas and "Sinusoidal Pulse Generator," by J. E. Madison. students. State University of Iowa; January 7. 1953.
"Electroencephalograph," by J. W. Baum. Student, State University of Iowa and open Discussion on "Student Engineers Lounge Plans"; January 14. 1953.
"Walkie-Talkie." by E. J. Tillo. Student. State University of Iowa. and open Discussion on "Possible Solutions to Practical Problems Encountered in Measurements in the Field of Medical Research"; January 21. 1953.
"Bell Telephone Laboratories." by H. A. Wells, Bell Telephone Laboratories; January 28, 1953.
Lot ISIANA STATE UNIVERSITY, IRE-AI F.E BRANCH
"Recent Developments in Power." by D. L. Chesnut, General Electric Company; November 12. 1952.
Film and General Meeting; December 9. 1952. "Traffic Signals," by J. A. Loupe and "The Applications of A.C. Series Motors in Locomotives." by F. V. Warner; December 12. 1952. "Engineering at Oak Ridge." by Gibson Morris. Carbide and Carbon Chemicals Company of Oak Ridge. Tenn.; January 6. 1953.
UNIVERSITY OF M AINE. IRE BRANCH
"Development of the Traveling Wave Tube." by Roger White, Federal Telecommunications Laboratories; February 10. 1953.
UNIVERSITY OF M ARYLAND, IRE-AIEE BRANCH
Binaural Sound Demonstration by Frank McIntosh, McIntosh Laboratories and Capt. Robert Hathaway. USAF; November 5. 1952.
"Transistors," by Dr. William Deurig, Johns Hopkins Institute; December 3. 1952.
"Telemetering of the V-2 Rocket." by Representative of Johns Hopkins Institute; January 7. 1953.
"The Control System of the Viking Rocket," by N. E. Felt, Jr.. Glenn I.. Martin Company; February II. 1953.
UNIVERSITY OF M ASSACHUSETTS, IRE-AIRE BRANCH
"The Use of Copper in the Electrical Industry." (Illustrated with two films), by I. T. Hook, American Brass Company; January 14. 1953.
M ASSACHUSETTS INSTITUTE OF TECHNOLOGY. IRE-AIEE BRANCH
Election of officers and business meeting; January 20, 1953.
M ICHIGAN COLLEGE OF M INING & TECHNOLOGY. IRE-AIEE BRANCH
"My Recent Tour of Duty in the West Pacific as Navy Radio Operator." by D. I. Fales. Student, Michigan College of Mining and Technology;·Janttary 13. 1953.
"Radio Station Management." by A. Payne. Radio Station WHDF; January 28. 1953.
"Technical Operating Procedure at WHDF." by George Burgan, Radio Station WHDF; February 10, 1953.
NEWARK COLLEGE OF ENGINEERING, IRE BRANCH
Tour of RCA Electron Tube Plant in Harrison. N. J.; February 3. 1953.
COLLEGE OF THE CITY OF NEW YORK. IRE BRANCH
Election of officers; January 8. 1953.
(Continued on page 92A)

W.\

PROCEEDINGS OF THE I.R.E.

April, 1953

liketlfelee l

/Oa

egledeer

Overload Trip

Calibrating Tap

Shunt Trip

ri [4.72, _

Relay Trip

II
··········..

Man tom aim emir man emu

MM.

Ina IIUM 1.111.

droulic-magnetic principl",
lowasppmliacxaitimounms, flreaxtiibnilgistyafnodr pr .
'five characteristics. Since it does .f employ thermal elements, set
ping points ore completely unffected by ambient temperatur

Perhaps the problem of protection or control of your equipment can be solved by a HEINEMANN Circuit Breaker.
Operating on a hydraulic-magnetic, solenoid principle . . . with or without inverse time delay ... HEINEMANN Circuit Breakers offer almost unlimited possibilities in fulfilling standard or special functions.
Your requests for special information will receive prompt attention.
SPECIAL CIRCUITS

SPECIAL OR FRACTIONAL RATINGS
Close tolerances of protection may be obtained by precise, fractional rating between 10 milliamperes and 100 amperes.

ALARM CONTACTS
Alarm contacts are available on certain models to permit visual or audible signal on tripping of circuit breaker.

DUAL RATINGS
A single circuit breaker may be furnished with two coils for operation on different currents.

SPECIAL RESPONSE CURVES

Time vs. per cent overload response curves

may be selected to match protection characteristics to the requirements of your

product.

Fop RIM 1FT1N Pie!

HEINEMANN ELECTRIC CO.

154 PLUM STREET

TRENTON 2, N. J.

HEINEMANN Circuit Breokers--One, two and three pole...10 milliamps to 100 amperes

i'RuCEEVINGS 01 1·11E I.R.E.

:

91A

(Continued from page 90A)

NEW YORK UNIVERSITY (EVE. DM), IRE-AIEE BRANCH
"Recent Developments in TV Picture Tubes," by Robert Scott, Dumont Laboratories, Inc.; January 23, 1953.

NORTH DAKOTA STATE COLLEGE. IRE-AIEE BRANCH
General meeting; December 3, 1952. Films, "Atomic Power" and "Atomic Energy"; January 26, 1953.
NORTHWESTERN UNIVERSITY, IRE-A IEE BRANCH
Student paper competition and talk by Dr. J. F. Calvert, Faculty. Northwestern University; January 13. 1953.
Films; January 20, 1953. Film, "Electrical Proving Ground"; January 27, 1953.

Our previous series of advertisements in this publication explained, in theatrical parlance, that our design and production facilities were pretty well "sold out" by the requirements of our present customers.
Now, we are happy to say (because we enjoy making new friends) that some of the heat has been taken off, and we are able to announce "Limited seating available"-as they say at the box office.
We shall be happy to talk with you about your present and/or future needs.

OHIO STATE UNIVERSITY. ¡RE-ALEE BRANCH Field trip to National Electric Coil Company;
January 29. 1953. Field trip to Ohio State University Cyclotron
Laboratory; February 12, 1953.
OKLAHOMA AGRICULTURAL & M ECHANICAL COLLEGE. IRE-AIEE BRANCH
"Low Voltage Metal Inclosed Switchgear for Industrial Power Distribution," by F. R. Summers, Westinghouse Electric Corp.; February 9, 1953.
UNIVERSITY OF PENNSYLVANIA. IRE-AIEE BRANCH Election of officers; February .5, 1953.
RENSSELAER POLYTECHNIC INSTITUTE, IRE-Al EE BRANCH
"Recent Developments of Klystron Tubes," by C. E. Rich, Sperry Gyroscope Company; February 10. 1953.
RUTGERS UNIVERSITY. ¡RE -ALEE BRANCH "Patent Law and the Engineer." by Morton Amster, counselor of law; February 10, 1953. Business meeting; February 17. 1953.
THE UNIVERSITY OF SOUTHERN CALIFORNIA, IRE-AIEE BRANCH
"The Instrument Story." by J. E. Berring, Weston Instrument Corp.; February 10. 1953.
STANFORD UNIVERSITY, ¡RE-ALEE BRANCII Field trip to Lenkurt Electric Company; Feb-
ruary 13, 1953.
UNIVERSITY OF TEXAS, IRE-AIEE BRANCH "Cybernetics," by W. T. Guy, Professor of
Applied Mathematics; February 2, 1953.
UNIVERSITY OF TOLEDO, IRE-AIEE BRANCH "Helpful Hints in TV Servicing," by D. F.
Davey and E. E. Swartz, Students, University of Toledo; December 5, 1952.

.H. Terpening Company
DESIGN · RESEARCH · PRODUCTION
icrowave Transmission Lines and Associated Components 6 W. 61 st St. · New York 23, N. Y. · Circle 6-4760

UNIVERSITY OF TORONTO, IRE-AIEE BRANCH
"Sound System for Opera Performances." by Mr. Goldin, Consulting Engineer; November 14, 1952.
"Professional Organization." by Roy Harmer, Lecturer at Ryerson Institute of Toronto; December 5, 1952.
"Computers." by V. G. Smith, Faculty, University of Toronto; January 16, 1953.
TUFTS COLLEGE. IRE-AIEE BRANCH
Business meeting; February 18. 1953. (Continued on Page 93A)

`)2A

PROCEEDINGS OF THE I.R.E.

April, 1953

KILOVOLTS for KLYS1RONS

ANEW

f. atit

UNIVERSAL

KLYSTRON [.·

POWER

¡,

SUPPLY

FOR

ir

MICROWAVE

OSCILLATORS L;

n
01) g ·
4 45

· Operates all low power commercial klystrons.
· Positive or negative grid operation.
· Widest modulation frequency range.
· Beam voltage: Regulated continuously variable over the ranges of 300 to 1500 volts at 65 ma. or to 3600
volts at 25 ma.
· Repeller voltage: Direct reading continuously variable over the range of
--20 to --750 volts.
· Grid volts: Variable bias is provided by front panel control. "Safety-Lock"
precludes tube damage.
· Modulation: Square wave, saw tooth, external or highly stable c-w operation.
WHEN YOU BUY-- SPECIFY THE PRO MODEL 801-A

RESEARCH II DEVELOPMENT COMPANY, Inc
202 TILLARY STREET. BROOKLYN I, NEW YORK Offices: 55 JOHNSON ST., BROOKLYN I, N. Y.

OPHAR
__WAXES
--COMPOUNDS

STUDENT BRANCH
MEETINGS
(Continued from page 92A)
UNIVERSITY OF UTAH, IRE-AIEE BRANCH "Electrical Engineering in the Bureau of Reclamation." by G. R. Derrick. U. S. Bureau of Reclamation; December 4. 1952. "What Industry Expects from Engineers," by S. S. Kistler, Dean, University of Utah College of Engineering; January 22. 1953. "Underwater Sound and Detection Devices," by Dr. Fred Huber. Naval Electronic Laboratory; January 29. 1953.
UTAH STATE AGRICULTURAL COLLEGE IRE BRANCH
"Forest Service Communication," by Francis Woods, U. S. Forest Service; January 28, 1953.
'Television on a Mountain Top or the Rise and Fall of ¡(SL T.V.." by V. E. Clayton. ¡(SL Television; February IL 1953.
UNIVERSITY OF VIRGINIA, IRE-AIEE BRANCH "Design of Broadcast Consolettes for An-
nouncer Use." by L. F. Goeller. Jr.. Student. University of Virginia; February 17, 1953.
VIRGINIA POLYTECHNIC INSTITUTE, IRE-Al EE BRANCH
Business meeting; January 13. 1953. Business meeting; January 20, 1953. Business meeting; February 10, 1953.
UNIVERSITY OF W ASHINGTON, IRE-AIEE BRANCH "The Northwest Power Problem," by F. D.
Robbins, Faculty. University of Washington; January 15, 1953.
General meeting and film, 'Watts in Glass"; January 29. 1953.
W AYNE UNIVERSITY, IRE-AIEE BRANCH "Instrumentation of Resistance Welding Machine Schedules." by A. R. Satullo, Instructor. Wayne University; January 9. 1953.

eteeà
tNee
E
MODEL M-2 OSCILLATOR
eget cutdwet

Zophar Waxes, resins and

compounds to impregnate, dip, seal, embed, or pot electronic and electrical equipment or components of all types; radio, television, etc. Cold flows from I00°F. to 285°F. Special waxes noncracking at --76°F. Compounds meeting Government specifications plain or fungus resistant. Let us help you with your engineering problems.

n ra 1111it

ZOPHAR MILLS, INC. 112-130 26th Street,

''>eiarte

Brooklyn 32, N. Y.

PROCEEDING.S UF THE I.R.E.

April, 1953

The unique SIE oscillator circuit which hos no lower limit to its possible frequency of oscillation is responsible for the excellent low frequency performance of the Model M-2 and other SIE oscillators

The following transfers and admissions were approved to be effective as of April 1, 1953:
Transfer to Senior Member
Alexander. W. G.. 6 Maguire Rd., Cochituate, Mass.
Ayer. W. E.. 95 Hilltop Dr.. San Carlos, Calif. Bargellini, P. L.. 15 Yale Sq.. Morton. Pa. Bauer. B.. 1089 Forest Ave., Palo Alto. Calif. Berglund. E. B., 56 Roosevelt St.. Garden City.
L. 1.. N. Y. Ebert, J. E.. 478 Whitehall St., Lynbrook, L. I..
N. Y. Franklin, C. S., 228 Lewiston Rd., Dayton 9, Ohio French, H. A.. 16 Howard Pl. Waldwick. N. J. Guida, J. A., 2904 Newcastle Ave.. Silver Spring.
Md. Gulden, E. V., 140 Oak Knoll Dr.. Dayton 9, Ohio Haggerty, P. E.. 5322 Falls Rd.. Dallas 9, Tex. Hassler. E. B., 5879 N. Kolmar Ave., Chicago 30,

SPECIFICATIONS
Range: 1 cps to 120,000 cps. Calibration. Within l'2% plus 1/10 cycle Output circuits: 20 volts or 20 millamps and
1 volt at 300 ohms constant impedance Amplitude stability: Plus or minus 2 db
UNDESIRED VOLTAGES
Power Supply Noise: Less than 1/100% of output signal
Power Line Surge: Less thon 1/10% of output signal
Harmonic Distortion: Less than 2/10% from
20 cps to 15,000 cps. Less than 1% at all other frequencies Microphonic Noise: Less than 1/100% of output signal
gr'

(Continued on page 94A)

frOigUTHWESTERN INDUSTRIAL 93A ELECTRONICS COMPANY

2R3 1

("1(.0- R,ad · Houston 19 Tel.' CPI

SHOCK r"

AND

VIBRATION

HERE'S THE SECRET

... of a NEW wire-mesh isolator that won't change
on the job!

The new Type 7630 and Type 7640 ALL-METL Barrymounts have been specifically designed to eliminate loss of efficiency due to damper packing. Previous wire-mesh unit vibration isolators exhibited adefinite loss of damping efficiency after aperiod in actual service, because the wire-mesh damper tended to pack. These new unit Barrymounts have eliminated this difficulty, because load-bearing spring returns damper to normal position on every cycle.

· Very light weight -- helps you reduce the weight of mounted equipment.
· Hex top -- simplifies your installation problems. · High isolation efficiency -- meets latest government
specifications (JAN-C-172A, etc.) -- gives your equipment maximum protection.
· Ruggedized -- to meet the shock-test requirements of military specifications.
· Operates over awide range of temperatures -- ideal for guided-missile or jet installations.

Compare these unit isolators with any others -- by making
your own tests, or on the basis of full details contained in Barry Product Bulletin 531. Your free copy will be mailed on request.

Free samples for your prototypes are available through your
nearest Barry representative.

BARRY THE

CORP

716 PLEASANT ST., WATERTOWN 72, MASSACHUSETTS
SALES REPRESENTATIVES IN Atlanta Baltimore Chicago Cleveland Dallas Dayton Detroit Los Angeles Minneapolis New York
Philadelphia Phoenix Rochester St. Louis San Francisco Seattle Toronto Washington

(Continued from Page 93A)
Heister, C. F.. 3200 Federal Office Bldg., Kansas City 6E. Mo.
Holbrook. R. 0., 405 Southwest Dr., Silver Spring. Md.
Ivers. J. H., 552 S. Border Rd.. Winchester, Mass. Jaeger. J. H., 361 Oakland Park Ave.. Columbus 14,
Ohio Kadet, J., 19 Shute Path. Oak Hill Pk., Newton,
Mass. King, S., Electrical Engineering Department, Uni-
versity of Tennessee. Knoxville, Tenn. Lundquist. C. R., 6686 DeAnza Ave., Riverside.
Calif. McKesson. L. J., 405 Upper Blvd., Ridgewood. N.J. McRae, A. H., 1623 Hearthstone Dr., Dayton 10,
Ohio Meyer. E. G., 45 Cumberland Ave.. Great Neck.
L. I., N. Y. Millard, A. M.. Southern New England Telephone
Co., 227 Church St., New Haven 6, Conn. Murphy, C. H. S., Bureau of Aeronautics Repre-
sentative, McDonnell Aircraft Corp.. Box 516, St. Louis 3. Mo. Pickens, D. H., 7518 S. Thomas Ave., Bridgeview. Chicago 38, Ill. Podolsky, L.. 18 Lexington Pkwy., Pittsfield. Mass. Powell. D. S., 3415-38 St.. N.W., Washington 16. D. C. Richardson, G. A.. Electrical Engineering Department, Iowa State College, Ames. Iowa Stubbs, W., Telecommunications Department. Kuala Lumpur, Malaya Thulin, C. W., Bell Telephone Laboratories. Inc.. Murray Hill. N. J. Van Valkenburg, M. E.. Engineering Hall, University of Utah. Salt Lake City 1, Utah Weinschel, B. 0., 10015 Woodland Dr., Silver Spring. Md. Wieland. E. S., 1203 Salem Ave., Dayton 6. Ohio Wilson, R. T., 426 Essex Dr., Lexington Park. Md.
Witkin, E.. 6801 N. II St., Philadelphia 26, Pa.
Admission to Senior Member
Ball. K. E., 2619 General Bradley. N. E., Albuquerque, N. Mex.
Bundy, C. W., USS MacKenzie (DD836). Fleet Post Office, San Francisco, Calif.
Cederbaum. I., Box 1. Kiryat-Motzkin, Israel Coapman, J. W., 240 Laurie St., Eau Gallie, Fla. Cumins, A. W., 1708 Windsor Ave., Lancaster, Pa. Fenyves, F. L., Basle (Switzerland) 75 Austr..
Basle. Switzerland Foster. L. W., 43 Cottage Hill Rd., Glens Falls,
N. Y. Hasley. A. D., 53 Cherry La., Basking Ridge, N. J. Hawthorne, E. I., Moore School of Electrical Engi-
neering. 200 S. 33 St.. Philadelphia 4, Pa. Hearn. R. B.. 463 West St., New York 14, N. Y. Holborn. F.. 15 Eastwood Pl., Cedar Grove, N. J. McPherson, J. C., 590 Madison Ave., New York 22.
N. Y. Means, W. J., 35 Whittredge Rd.. Summit, N. J. Nichols, N. B., Manager of Research Division,
Raytheon Manufacturing Co.. Waltham 54. Mass. Plummer, D.. 3116 Elm Ave., Manhattan Beach. Calif. Raney, J. J.. 140 W. Center College St., Yellow Springs, Ohio Schisel, J., 105 New England Ave.. Apt. F-8, Summit, N. J. Schneider. S. S.. Canadian West inghouse Co.. Ltd.. Longwood Rd., Hamilton, Ont., Canada Scott, J. E., 325 S. Central Ave.. Fairborn. Ohio Sheldon. J. L., 179 Dodge Ave.. Corning, N. Y. Sutinen. C. P.. 317 W. Third St., Moorestown. N. J. Thomas, J. E., Jr., 49 Kendal Common Rd., Weston 93, Mass. Wynn. R. T. B.. British Broadcasting Corp.. Broadcasting House. London W.1, England
(Continued on page 98A)

9

PROCEEDINGS OF THE IRE.

April, 1953

Your Search for the Right Protection

P644 acomplete line of fuse clips, blocks and fuse holders

on BUSS Fuses..
the complete line for Television ·Radio ·Radar Instruments ·Controls and Avionics
Whatever your protection requirements, you'll find the right fuse faster when you look first to BUSS. All types and sizes, from 1/500 ampere up, are included in the complete BUSS line. This can simplify your purchasing and stock handling.
To assure protection to both the product and your good name, every BUSS fuse is tested on asensitive, electronic device for correct construction, calibration and physical dimensions.

TO HELP YOU GET STARTED THE RIGHT WAY BUSS Fuse Engineers will gladly assist you
in selecting the fuse to suit your needs best... afuse that if possible will be available in local wholesalers stocks.

BUSSMANN Mfg. CO., Division of McGraw Electric Co. University at Jefferson, St. Louis 7, Missouri

PROCEEDINGS OF TI1E 1.R.E.

April, 1953

· BEIM

UM

BUSSMANN Mtg. Co )i vision of McGraw Electric Co.) University at Jefferson, Sc. Louis 7, Mo. Please send me bulletin SFB containing facts on BUSS small dimension fuses and fuse holders.

Name
Tide
ICompany 111 Addresx
City & Zone

Stale

IRE-433
95A

CANADIAN BROADCASTING CORPORATION NOW AT...
NouRe
/WITH 3Federal
50 KW POWER TRIODES
Used in 18-Hour Daily Runs!

Federal F-9C31 22,255 HOURS Still in Service

Federal F-9C29 21,015 HOURS Now used as a Spare

à _
Federal F-9C31 25,629 HOURS Still in Service

THORIATED · Tungsten Filamen
in Federal's F-9C31 ·F-9C29 ' SAVE POWER EQUAL TO THE,
PRICE OF NEW TUBE PER YEAR!

THIS is the life story of 3of numerous Federal power
triodes used by the Canadian Broadcasting Corporation at station CBX, Lacombe, Alberta: Since October, 1948, to recent date, these tubes have served for 69,000 hours. Both F-9C31's appear to have full emission and
capability of many more hours. The F-9C29 -- used in modulator unit -- is on standby after 21,015 hours.
Behind the long performance of these 3tubes is Federal's pioneering in the multi-strand thoriated tungsten filament, which permits hairpins to expand individually

...eliminates stresses which might be conducive to filament warping.
Cathodes of this type provide lower operating temperatures ...keep components cooler, more durable. Because less filament power is consumed, tube life is longer ...operating costs are lower. The power saved per-tube-per-year equals the price of anew tube!
For full information on Federal's F-9C31 and F-9C29, or Federal quality-controlled tubes of any power output, write Dept. K-137.

Federal always has made better tubes"

Federal Telephone and Radio Corporation

VACUUM TUBE DIVISION

100 KINGSLAND ROAD, CLIFTON, N. J. In Canada, Federal Electric Manufacturing Company, Ltd., Montreal, P. Q.
Export Distributors: International Standard Electric Corp., 67 Broad St., N. Y.

PROCEEDINGS OF THE I.R.E.

April, 1953

RAM 11/IGII

UG111/11

Mlle °SE
I, designed,
bunt. and inspected to ins ure su perior
perform ance

Se· L.,
SO , V:14
L

e 31/4" WAVII.f

This New, 12-Page .g Microwave Components
Data Book

SEND FOR YOUR COPY
Contains diagrams and tables of sizes and types--detailed Government specifications
for rigid and flexible waveguides-- manufacturing and testing operations. If you're working on electronic contracts, this Handbook belongs on your desk. The coupon brings you as many copies as you need.

PROCEEDINGS OF THE I.R.E.

April. 1953

ILIteflex

TITEFLEX, INC. 511 Frelinghuysen Avenue Newark 5, N. J.
Please send me without cost Microwave Components Data Book.

copies of your new

NAME TITLE FIRM ADDRESS CITY

ZONE

STATE

For the first time

FLEXIBLE WAVEGUIDE with power rating
equal to that of rigid guide!

(Continued from page 94A)

Transfer to Member

Attack. H. G., 579 James St.. S.. Hamilton. Ont..

Canada

for

Bailey. W. R.. Texas Instruments, 6000 Lemmon Ave.. Dallas 9, Tex.
Bauer, R. E.. U. S. Naval Postgraduate School.

HIGH POWERED

Monterey, Calif. Bennett. R. C.. 2239 Marconi Ave.. Sacramento 21.
Calif. Brock, F. A., 5422 Druid La.. Dallas 9. Tex. Cook, M. F., 6307 Tecumseh Pl.. College Park. Md.

14LEXAGLIIDk

D'Arcy. E. W.. 7045 Osceola Ave., Chicago 31, Ill.
c' Finn. D. L.. School of Electrical Engineering. Georgia Institute of Technology. Atlanta.
Ga. Gagnon. L. A.. Box 166, 235 Second Ave.. Port

Alfred, Que., Canada

for RADAR applications

Hansen, H. M., 1314 Walden Rd., Walnut Creek. Cal if.
Healey. D. J.. Ill, Shanan Rd.. Cockeysville. M CI.

Helland, J. C.. 24 Flannery Ave., Poughkeepsie. N. Y.

Hensel. W. G., 265 Washington Ave.. Chatham,

NOW you can route your R.F. circuits into previously impossible channels, without power, V.S.W.R. or attenuation penalties

Broad- band FLEXIBLE assemblies guaranteed to a V.S.W.R. of less than 1.10-- attenuation equal to that of brass rigid waveguide--yet none of the essential advantages of flexible plumbing sacrificed to achieve this new type of waveguide! Performance is what counts; let us show you ...
Write for data sheets on new, high powered
FLEXAGUIDE

N. J. Khouri, A. S., Centralab. a Division of Globe-
Union. Inc., 900 E. Keefe Ave., Milwaukee 11. Wis. McCarter, G. B., 8310-16 St., Apt. 116. Silver
Spring, Md. Moore, A. D., 604 East 23 Ave.. Vancouver 10,
B. C.. Canada Nelson, R. T.. 94 Pershing Ave.. Valley Stream.
L. I., N. Y. North, R. C.. Jr., 2844 East 26. Tulsa, Okla. Nylin, M. E.. 454 Douglas Ave., Toronto 12. Ont..
Canada Page, F. E., Jr., 1116 Post St., Houston, Tex. Post. R. F.. 1004 N. Kedzie Ave.. Chicago 51, Ill. Quint, A. S., 55 Lee St., Cambridge 39, Mass. Richman, H. R., Box 658, R.F.D. 2, Fairfax, Va. Schroeder, K. R., 43-28 Byrd St., Flushing 55. L. I..
N. Y. Scroggins, C. M.. 4154 Prescott Ave., Dallas 9. Tex. Shainis, M. J., 99 Featherbed La., New York, 52.
N. Y. Snow, J. E., Far East Air Logistic Force, APO 323.
c/o Postmaster, San Francisco, Calif.
Stachiewicz, B. R., 926 E. Hastings St., Vancouver 4, B. C., Canada

Stewart, G. L., 25 Thursfield Cresc.. Toronto 17.

Ont.. Canada

Villadamigo, R. D., Apartado Nacional No. 765.

Barranquilla, Colombia, S. A. Stewart, J. L., 315 Apt. No. 6 Stanford Village.

Stanford, Calif. Swierczak, P. C., 6716 Harvey Ave., Merchantville

rg
/4

oag -see,

8. N. J. Trebby, F. J., 4128 S. Garfield St., Spokane 36.
Wash. Weis, C. F., 57 N. Bromfield Rd., Dayton 9, Ohio

20

r4L)

1.4
IS · 71 · do

; 3 .7 7." 6 76

1,,,,t.4.0 Wary - 5 .44 414.

4P4i-erre--e9w8e0*4.

14eJej Pie
erAtutr.ore

000

AI/07700N

/1/.../e4

Admission to Member
Allen, D. H., 2180 Colorado Ave.. Santa Monica. Calif.
Atchison, F. S., 6197 Palm Ave., Riverside, Calif. Brumbach, J. F., 9736 Johanna Ave., Franklin

TEc5 T Re/A,/ Me14.9E'Re

Park, Ill.
Brunson, R. A., R.F.D. I, 10 Elm St., Florham Park, N. J.
Byrnes, W. P., Teletype Corp., 1400 W. Wright-

wood Ave., Chicago 14. III.

Cammer, H. R., 231 Argyle Rd., Brooklyn 18, N. Y. Campbell. A. A.. 4812 Southern Ave., S. E., Albu-

inc.

BRANCH OFFICES CHICAGO ST LOUIS DAYTON DALLAS

querque, N. Mex. Cornell, W. A., 27 Forest Rd., Murray Hill, N. J. Dawson, L. R., 432 A Kalama St., Lanikai, Hawaii

20 East Elizabeth Ave., linden, New Jersey

BALTIMORE LOS ANGELES SEATTLE

Doxey. W. L., 239 Albert Pl.. Elberon, N. J.
(Continued on page 100A)

98.

PROCEEDINGS OF THE I.R.E.

April, 1953

Why Motorola uses Corning Metallized Glass Inductances in new UHF converter

UHF converters present atough design problem. Not only must they tune an unusually broad band, stability is extremely important.
Motorola solved their problem with aspecially designed CORNING metallized glass inductance. As can be seen from the illustration, the tuning elements are acombination of distributed capacitance and inductance. The variable pitch winding tailors the unit to the desired tracking curve. One end of the turns is broadened to provide termination surface. The accuracy and rigidity of the glass assure stable, noiseless tuning.
The exceptionally high electrical stability and low temperature coefficient of CORNING metallized glass inductances are aresult of the integral contact of the fired-on metallizing with the dimensionally stable glass coil forms. Drift is negligible, even under unusually variable ambient temperatures. High Q is inherent.
CORNING metallized glass inductances may well be the answer to your problem. All it takes to find out is aletter to us. Our engineers are ready to go to work for you.
Corning Glass Works
New Products Division ·CORNING, N. Y.
at/a:Y7. ,mew /weasel e:c 6 P4/1

PROCEEDINGS OF TIIE I.R.E.

April, 1953

CORNING Metallized Glass Inductances can be designed to fit your requirements exactly. Uniform, variable or double pitch windings are as easily manufactured as are fixed tuned, permeability tuned or permeability tuned inductance-trimmer combinations. Once adesign has been approved, it can be accurately duplicated on automatic machinery to very close tolerances and in any quantity.

CORNING Metallized Glass Trimmer Capacitors are available in standard types from .3 to 12 u.u.f. or can be designed to meet your own particular needs. They are simple to solder, rugged and easy to tune critically. Their superior electrical characteristics are similar to CORNING inductances.

·

Corning Glass Wcrrks
Department NP-3 · Corning, New York

Please send me literature on
ID Metallized Glass Inductances, D Metallized Glass Trimmer Capacitors.

Name

Title

Company City
I.

Zone

State

BECO DEKÁD1AL for accurate resistance, capacitance, inductance. Readings to four
significant figures.

RANGE SELECTOR: seven positions
Universal BINDING POSTS connect to all bridge arms

CIRCUIT SELECTOR: six positions

IMPEDANCE BRIDGE
?eide Za.ege
Resistance: 1milliohm to 11megohms Capacitance: 1mmf to 1100 mfs. Impedance: 1 mir to 1100 henrys
ateee4N4111 A fffleretelf
Resistance: '0.1°4 Capacitance: '0.25%
Inductance: r- 1.0%

SHOWN MODEL 250-CI
$340
9"x 11"x 11" over -all. Convenient operation from battery, or from AC power lines with Beco accessory amplifier

75 ,,a -0-73 ,a GALVANOMETER

Write to factory for literature and analysis of your needs.

DROWN ElECTRO-MEASOREMENT CORP. 4635 S. E. HAWTHORNE BLVD. PORTLAND 15, OREGON

FOR FREQUENCY
Stability

(Continued from page 98A)
Ellen. S. T., Smith Ave.. R.F.D. 7, Baltimore 9, Md.
Fraser. F. S.. 1777 West Third Ave.. Vancouver. B. C., Canada
Fricks. W. H.. 909 Borum Pl.. Oklahoma City 10. Okla.
Gaunt, R. P., 8430 Lennox Ave.. Van Nuys, Calif. Godsey, W. J., 1023 Eastern Ave.. Baltimore 21.
Md. Harden. C. M.. 78 Pierce Rd.. Watertown, Mass. Heimlich. I. R., 2209 Graham St.. Grand Prairie,
Tex. Horn, C. FL, Rm. 210. 1401 Arch St.. Philadelphia
2, Pa. Hunter, W. 0.. 2732 N. Serrano Ave.. Los Angeles
27. Calif. Johnston. W. A., Jr., Fairchild Guided Missiles Di-
vision. Wyandanch, L. I., N. Y. Jose, R. S., R.F.D. 2, Rancocas Woods, Mt. Holly.
N. J. Keating, J. J., 3112 Chadwick Dr.. Los Angeles 32.
Calif. Kelton, M. R., Box 146. Montreal, Que.. Canada Knowlton, R. F., R.F.D. 5, 1502 E. Alta, Wichita
15, Kans. Low, A. R., 578 Broadway Ave.. Toronto 17, Ont..
Canada Mentzer.P.K ., 3201 Wooster Rd.. Rocky River 16.
Minidis. AO.h,i9o544 Lenore St.. Detroit 28. Mich. Morris, H. N., 213 Beverly Rd., Cocoa, Fla. Newnan, H. L., 420 Market St., San Francisco 11,
Calif. Perry. F. M.. 2000 Pyle Rd.. Schenectady 3. N. Y. Rae. J. R.. 171 Riverview Ave.. Tarrytown. N. Y. Ralph. J. T., 2027 S. Newton Ave.. Park Ridge, Ill. Ross, R. M., Sylvania Electric Products, Inc.. 1740
Broadway, New York 19, N. Y. Sperber. A. O., 7407-64 Pl.. Glendale 27. L. I..
N. Y. Stelmak, J. P.. Westinghouse Electric Corp.. Box
284, Elmira, N. Y. van der Lee, A. C., 707M Lima. Buenos Aires,
Argentina Warner. F. C., 12 High St.. Bethel. Conn. Zomber, G. L.. 22 Dartmouth St., Garden City,
L. 1.. N. Y.

100A

IN
Mobile
EQUIPMENT ....
make sure your crystals are made by Standard Plexo. For years. our Crystals have been standard as original equipment
with leading manufacturers and for replacement purposes by large operators of mobile equipment.
Precise, accurate, Standard Piezo Crystals are available for ALL types of mobile communication equipment.
Request catalog R for complete details.
amiummaimimmumal.

The following elections to Associate grade were approved to be effective as of March 1, 1953:
Adair, R. J., 19 Proctor Blvd., Hamilton, Ont., Canada
Adams, H. E.. Qtrs. W 15. NRL, CBA. Chesapeake Beach, Md.
Adamson, W. V.. 306 W. Mayfield Blvd., San Antonio. Tex.
Albert, D. E., 918 Hamilton Ave.. Latrobe. Pa. Allard, L. C.. Jr., Box 3024. Wright-Patterson AFB.
Dayton, Ohio Allen, D. F., 7Alcott St.. Allston 34. Mass. Ambrogi, J. N., Jr., 319 Lincoln Ave., Lansdowne,
Pa. Anderson, W. L., 127-96 St.. San Antonio 4. Tex. Anlage. J. J., 52 Winding Way. Haddonfield, N. J. Avella. P. S.. 2155 N. Mobile Ave., Chicago 39, III. Barr. F. M., 1380 North Ave.. Elizabeth 3, N. J. Barr, H. J., 813 E. Seventh St., Plainfield, N. J. Basa, C. F.. 350 Saxon Rd., Latham, N. Y. Bazydlo, H. A., 4737 Plumer St.. Detroit 9, Mich. Beaver, M. W., 712 Crown St., Brooklyn 13. N. Y. Beck. C., 5838 Cedar Ave.. Philadelphia, Pa. Becker, H. R.. 20-04 Woodbine St.. Ridgewood.
L. I., N. Y. Behringer, N. C., 29 Deer La.. Wantagh, L. I., N. Y. Bellingham. L. C.. Natvar Corp.. Box 67, Rahway.
N. J.
(Continued on page 1.01A)

PROCEEDINGS OF THE I.R.E.

April, 1953

STANDARD

(Continued from page 100A)
Beltway. R. E.. 1641 Old Phila Pike. Lancaster, Pa. Bernard. D. T.. 126 Cedar St.. Wethersfield. Conn. Blicher. A.. 535 W. 110 St., New York 25. N. Y. Bloom. L., 3509 Virginia Ave.. Baltimore 15. Md. Bolay, C. E.. c/o Two-Way Radio Communication
Co.. 505 N.W. Second. Oklahoma City. Olda. Bowe. J. J.. 6 Bunton St.. East Milton 86. Mass. Brumley, C. H.. 183 Collingsworth Dr., Rochester 10. N. Y. Buchinger, M. J.. 74 N. Fourth St.. Paterson. N. J. Bunnell, N. R., 1410 Delaware Ave.. `Vyomissing. Pa. Burr. G. S.. Instron Engineering Corp., 2 Hancock St., Quincy 71. Mane. Busteed. P. E., 25 Irving Ter., Cambridge. Mass. ('allegan. P. B.. 12331 S. Yale Ave.. Chicago 28, III. Campani. L. M.. 116 W. Merrick Rd.. Freeport. L. I.. N. V. Cape. K. E.. 3040 S. Emerald Ave.. Chicago, Ill. Carroll. L. R.. 925 E. Baseline Rd.. Claremont, Calif. Cervantes. H. T.. Jr.. E73, ER Division. U.S.S. Tarawa (CVA-40). c/o FPO, New York. N. Y.
Chase, W. R., 368 Burkedale Blvd., San Antonio 10. Tex.
Chiappinelli. B. A.. 10790 Calvin St.. Culver City. Calif.
Chinn. F. T., 2917 West 71 St., Kansas City 13, Mo. Cichanowice. H. J., 550 Deeds Ave., Dayton 4.
Ohio Clark. A. R.. 25 Wanamassa Point Rd.. Wanamassa,
N. J. Callen. F.. 330 W. Johnson St.. Philadelphia 44. Pa.
(Continued on page 102A)
, Over 85% of the torque wrenches
used in industry ore
5 /RIÉ lee
TORQUE WRENCHES
Read by Sight. Sound or Feel.
· Permanently Accurate
· Practically Indestructible
· Faster--Easier to use
· Automatic Release
· All Capacities
in inch ounces ... inch pounds ... foot pounds (All Sizes from 0-6000 ft. lbs.)

Every Imanufacturer,
design and production man
should hove this valuable / data. Sent upon

"1>P.

request.

/5tuRti PA

VA NI1C 0

A00/50N gILIAI IT ti lz zhVOI5

PROCEEDINGS OF THE I.R.E.

April, 19.53

MEASURING EQUIPMENT
Complete Frequency Coverage --14kc to 1000 mc!
14kc to 250kc
Commercial Equivalent of AN/URM-6B. Very low frequencies.

150kc to 25mc
Commercial Equivalent of AN/PRM-1A. Self-contained batteries. A.C. supply optional. Includes standard broadcast band, radio range, WWV, and communications frequencies. Has B.F.O.

por ·

,r:

15mc to 400mc
Commercial Equivalent of
TS-587 U. Frequency range includes
FM and TV Bands.

375mc to 1000mc
Commercial Equivalent of AN URM-17. Frequency range includes Citizens Band and UHF color TV Band.
These instruments comply with test equipment requirements of such radio interference specifications as MIL-I-6181, MIL-I-16910, PRO-MIL-STD-225, ASA C63.2, 16E4, AN-I-24a,
AN-I-42, AN-I-27a, MIL-I-6122 and others.
STODDART AIRCRAFT RADIO Co., Inc.
6644-C Santa Monica Boulevard, Hollywood 38, California
jli

IT'S
HARI/1E
FOR PROMPT "OFF-THE-SHELF"DELIVERY

WRITE PHONE
or WIRE

Whether it's equipment, components or other electronic requirements, you will always find them in Harvey's extensive stocks, ready for immediate delivery to you anywhere.
Harvey's twenty-five years of service to the industry are your assurance of understanding 'know-how' and complete dependability.

Telephone LUxemberg 2-1500

HARVE
RADIO COMPANY, INC.
103 West 43rd St., New York 36, N. Y.

(C"ntinura

rape 10IA)

Cohen. M., 3855 Nautilus Ave., Brooklyn 24. N. Cole. W. M., Jr.. 908 N. Wayne St.. Apt. 305. Ar.
lington, Va. Conlin, H. T., 1002 W. Market, Sandusky. Ohio Cook. K. W.. 5818 Access Rd., Dayton, Ohio Corey, J. F.. Box 1619, Balboa, Canal Zone Cox. J. A., 1922 Winton Ave., Indianapolis 24. Ind Croom, W. J.. 1426 West 40 St., Norfolk 8. Va. Cutler, M. A., Bradley, Plainville, Conn. Da Grosa. V.. c/o Shallcross Manufacturing Co..
Jackson & Pusey Aves.. Collingdale. Pa. Davies, R. W.. 457-B Allenhurst Rd., Buffalo 23.
N. Y. Davis. C. J.. 1634 S. 51 St.. Cicero 50. III. Dehm. R. E., 87 Englewood Ave., Buffalo 14. N. Y. Dehmlow, L. L.. 1318 S. Walnut Ave., Freeport. Ill. Denyer, J. H. N.. 736 Goulding St.. Winnipeg.
Man., Canada Dew. C. D.. c/o The Ohio Bell Telephone Co.. 42 E.
Gay St.. Columbus 15, Ohio Digenova, F.. 12 Carobene Ct., Newburgh. N. Y. Dill. J. M.. 12215 Victoria St.. Los Angeles. Calif. Dinunno, J. J., Cedar Lane, Ednor. Mo. Donovan, R. F.. 136 State St.. West Lafayette, Ind Douglas, J. H., 211 Buto, San Antonio, Tex. Doyle, W. A., Box 3124, USAFIT. Wright-Pat ter·
son AFB. Dayton. Ohio Drenchko, J. D.. c/o Naval Air Development
Center, Johnsville, Pa. Drukaroff. I.. 602 Seventh St., Lakewood. N. J. Edwards, D. E.. 1214 Ransom St.. Sandusky, Ohio Eisenbach. M. E.. 16727-39 Ave.. N. E.. Seattle
55, Wash. Elfman. R. S., 4706 N. Magnolia Ave.. Chicago 41)

RESISTANCE
714 RACE ST.

MINIATURE
HERMETICALLY SEALED PRECISION WIRE WOUND
Where the utmost in permanence and stability are required, Type S has proven successful. Unaffected by extreme temperature cycling, aircraft altitude or salt water immersion.
Wound on steatite forms, solder sealed into steatite jackets. Vacuum tested. Long leakage path. Can be wired into circuit. Self supporting. Low coefficient alloys used.
Standard resistance tolerance 1%, IA% and V4% also available. Write for complete information and engineering data.

TYPO

Dimensions Len. Diam.

,Power Rating Jan·R·93,
Ij.,,. Rantoul.

Resistance
eh; Max. melt

5/15 11/32

-- watts lie 2.0 0.16

Sc. 13/14 I1/32

RB51A

s Wittà

1.0 0.40

SRO 13/18 15 i2 nnnn,,

n, web M a

0 .,

1.0

PRODUCTS CO. HARRISBURG, PENNA.

Elston, J. A.. 271 Harbor St.. Conneaut, Ohio Euler. L. J.. Jr., 5055 Franklin Ave., Los Angeles.
Calif. Eve. D. R., Box 72. AA & GM Branch, TAS, Fort
Bliss, El Paso. Tex. Farrell. R. L., I. A. Pak. Ltd., David Sassrmn Bldg.,
McLeod Rd., Karachi 2, Pakistan Fellhauer, H. E.. 5841 El Monte Dr., Mission.
Kans. · Fiebich, E. C.. Heath Co., Benton Harbor, Mich. Field, G. R.. 211 Harding Ave., Collingswood 7.
N. J.
Fitzsimmons. T. J., Round Hill Field Station. South Dartmouth, Mass.
Fleischer. A.. 2912 Second St., SE.. Washington 20. D. C.
Flynn, J. E., 6625 McCallum St., Philadelphia. Pa. Foley, T. J., County Line Rd., Hatboro. Pa. Forte. S. S., Electrical Engineering Department.
The University, Leeds 2, Yorks, England Freedman, L. M., 106511 Ashton Ave., Los Angeles
24, Calif. Freyberg, J. A., 529 Pearl St.. Sandusky, Ohio Fried, G., 17 Normandy Dr.. Bethpage, L. I., N. V. Fujiki, S., 1-73 Shin-Machi, Setagaya-Ku. Tokyo.
Japan Gagnon, R. L., 36 Ocean Ave.. Salem, Mass. Gaskell. R. J., 32 Barker Ave., Eatontown. N. J. Gaskill, R. A., University of Michigan. Willow Run
Research Center, Ypsilanti, Mich. Gen, E. B., 8738 N. Peninsular, Portland 17, Ore. Getty, J. N., Hq. 1125 FAG, Box 9531 ATIC
Wright-Patterson AFB, Ohio Gibbons. J., Price Waterhouse dr Co.. 56 Pine St.
New York. N. Y. Gillespie, L. H., 125 W. Weinert St.. Seguin. Tex. Goldfarb, J., 3521 Cedarbrook Rd.. University
Heights. Ohio Granoff, N. H.. 73-31-187 St., Flushing 66, L. I..
N. Y. Greene. R. L., 418 Morton St., Sharon, Pa. Grossman, F. J., 39 Sickles St., New York 34, N. Y. Habermann, C. L., 3309 Columbus Ct., Apt. II.
Columbus 9. Ohio

(Continued on Page 106A)

PROCEEDINGS OF THE I.R.E.

April 1953

When TV manufacturers discovered that higher vo ages of the new 27 and 21-inch television receivers rendered existing wax corona ring sweep transformers inadequate, they brought the problem to Guthman.
In acooperative program with these TV engineers, a flyback transformer with a cast resin corona ring
was developed--the perfect answer to this difficulty.
Your problems in the development of coils and transformers are welcome at Edwin L Guthman &
Company, Inc., 15 South Throop St., Chicago 7, Telephone: CH 3-1600, also Attica, Indiana.

o

WHAT ABOUT THE
Wattage Rating

OF PRECISION WIREWOUND RESISTORS?

The wattage rating of precision wire

Iresistors

is often expressed in two forms--the manufacturer's

commercial catalog rating, and the JAN -R-93 or

MIL-R-93A rating. Exceptions are the many resistors

smaller than JAN and MIL dimensions .not rated

under JAN or MIL specifications.

held to asafe proportion of the breakdown voltage. Computation using JAN-M1L wattage ratings,
maximum resistances, and voltage limitations, reveals that voltage derating is seldom necessary up to 99% or more of JA N-M II. maximum resistance values.

THE BASIS FOR WATTAGE RATINGS: Production resistors are wound with resistance wire insulated with either or both enamel and asilk or nylon covering which deteriorates rapidly above 105°C.
JAN and MIL wattage ratings are based on an ambient temperature of 85°C. The wattage rating is limited to the power dissipation which will cause not more than a20°C temperature rise. This results in a temperature of not more than 105°C at the hottest point ("hot-spot") on the winding.
Shallcross commercial ratings are based on an ambient of 25°C. Wattage rating is *ted to the power dissipation which will cause not more than a 20°-40°C rise. Although higher, these ratings are based on hot-spot temperatures of only 45°-65°C. VOLTAGE DERATING AND RESISTANCE: Above about 50 per cent of the cataloged maxim lllll resistance, the Shallcross commercial wattage rating must be derated by the maximum voltage tabulated in the catalog. Lower thermal efficiency of the small diameter wire used for higher resistance values causes a higher temperature rise for the same dissipation, and the potential gradient in the winding must he

TOLERANCE DERATING: JAN, MIL. and Shallcross .nial wattage ratings are based on resistors
with 1% tolerance. For closer tolerances, the following MIL derating system is a good one to use:

Resistor Tolerance--%

Per Cent of Nominal Wattage

0.5 0.25 0.1

100 75
50 50

SPECIAL HIGH WATTAGE RESISTORS: Shalleross

also (IffITS

-mini iii' Ii I., preriS1011 wire,, ounil re-

sistors rated 5 to 10 t*

higher than the usual

ycial wattage ratings. These "G" type resistors

are wound with glass-insulated. low T.C. wire, sili-

cone varnished. They are rated on a 150°C tempera-

ture rise above an a.mbient of 25°C. Their hot-spot temperature is 175°C.

Shalleross also supplies "S" type resistors wound midi silicone-enameled low T.C. wire. Better insulation permits these resistors to operate at higher than normal hot-spot temperatures. Exact ratings are still being established. but they can be expected to approach those of "G" resistors while permitting higher maxi ttttttnresistance values.

Further details on Wattage Ratings and other resistor characteristics are available in Shancrou Bulletin R-3C

SNALLCROSS MANUFACTURING COMPANY · 524 PUSEY AVENUE, COLLINGDALE, PA.

The third of aseries to promote abetter understanding of the performance characteristics of precision wirewound resistors.

104A

PROCEEDINGS OF THE I.R.E.

April, 1953

PROCEEDINGS OF THE I.R.E.

April, 1953

NEW 3-WATT RESISTOR
Shallcross Type S 183-A it typical of the higher wattage ratings possible with siliconeenameled wire. Yet it measures only ,96" L. x 1/ 2 " Diom. Maximum resistance is approximately 500K ohms.
8-WATT PRECISION WIREWOUND RESISTOR
Wound with glass-insulated wire, silicone-impregnated, this Shallcross Type G 196-E resistor will dissipate 8 times the nominal wattage of the standard Type 196 resistor. Maximum resistance is 60K ohms. 11/ 4 " L. by 1/ 4 " Diam·
HIGHEST WATTAGE STANDARD RESISTOR
The BX 116-2E is the largest Shallcross resistor using standard resistance wire. Rated at 4-watts, the dimensions are only 31/ 4 "L. by 1 /4 " Diameter. Maximum resistance is 20 megohms.

offers acomplete line of antennas for the 450-470 MC ba cl.

The Isopole antenna, omnidirectional, rugged, inexpen.sive Type N input.

The High Gain antenna, omnidirectional, gain 6DECIBELS PLUS.

The Yagi antenna, two models with gains of 9.5 db and 12 db horizontal or vertical polarization.

The Corner
Reflector antenna, 8db forward gain, broadband, horizontal or vertical polarization.

CORPORATION

ANTENNA SPECIALISTS
363 EAST 75TH STREET, CHICAGO 19

TRANSMISSION LINES FOR AM.FM.TV·MICROWAVE · ANTENNAS · DIRECTIONAL ANTENNA EQUIPMENT · ANTENNA TUNING UNITS · TOWER LIGHTING EQUIPMENT'

(Continued from page 102A)
Hall. O. C.. 1001 Wedgewood Rd.. Baltimore 29. Md.
Hanks, W. R., 2365 Ardmore Ter.. Winston-Salem. N. C.
Harkless. E. T., 435 Myrtle Ave.. Scotch Plains. N. J.
Harms, A. D.. Jr., 6806 Quincy St.. Philadelphia. Pa.
Hauptli, J. T., 1111 Rice Ave., Bellwood, Ill. Herman, H. F.. 3223 Reynolds St., Dallas, Tex. Hines, T. H.. 1512 Ruth Ave., Cuyahoga Falls.
Ohio Hobbs. W. D., Jr.. 11741 Stamy Rd., Whittier.
Calif. Hochman, D., 239C Haddon Hill Apts.. Haddon-
field, N. J. Holmquist, J. A., 2108 Ottilia St.. Utica, N. Y. Holt, T., 443 West 71 St.. Los Angeles 3. Calif. Horn, S., 1178 Pacific Ave., San Francisco 11, Calif. Horwitz, J. D., 3128 Diamond St.. Philadelphia, Pa. Houston. R. W.. Far East Network Kyushu, Fenco.
8313 Army Unit, APO 3. c/o Postmaster. San Francisco, Calif. Hurford, A. C.. 96 Lakeside Dr.. Levittown, Pa. Husenita. J., 21 Palmer Rd.. Yonkers. N. Y. Jones, J. F., 4401 Hanover St., Dallas 5, Tex. Jordan. E. 1.. 440 N. Broadway. Yonkers, N. Y. Karney. T., Jr.. 722 Third St.. Box 253. Harvey. La. Kazarian. R., c/o Ohio Crankshaft Co.. 3800 Harvard Ave., Cleveland I. Ohio Kean, P. M., Sr., 3570 W. Granville Rd.. Worthington, Ohio Kelley, L. M., 109 Follen Rd., Lexington 73, Mass. Kelly, R. J., 515-30 St.. Union City, N. J. Keough, D. D., 12224 Allengrove St., Philadelphia 24, Pa. Kephart, E. T.. 4309 Willis Ave., Merchantville 8. N. J. Kimball. L. R.. 2Curve La., Levittown, L. I., N. Y King, L. G.. Navy 961. Box 29. c/o FPO. San Francisco, Calif. Klein. M. S., 3130 Brighton Sixth St.. Brooklyn. N. Y. Klucarich, S., 131 Beaver St., Fallston. New Brighton. Pa. Knudsen, D. F., 347 Adelaide St., W.. Toronto. Ont.. Canada Kravitz. J. S., 4630 N. Beacon St., Chicago 40. III Kumm, W. H.. Air ARM Division, IDF, Westinghouse Electric Corp., Friendship International Airport, Baltimore, Md. Kundler, H. H.. 1East 57 St., Rm. 701. New York. N. Y. LaCoste, L. J. B.. 3810 Speedway. Austin, Tex. Ladouceur, C.. 1193 Notre-Dame, Joliette. Que.. Canada Lahanes. C. J., 275 Massachusetts Ave., Cambridge. Mass. Lamartin. F. H., Apt. 1-4, U. S. Naval Academy. Annapolis. Md. Landow. I. S., 103 Neptune Ave.. Brooklyn 35, N. Y. Lane, J. W., 7420 Reeds La.. Overland Park. Kans. Larkin. W. E.. $001 Blanco St.. El Paso. Tex, LaRocca, J. J.. 4255 N. Bernard St.. Chicago 18.
Lawler. E. D.. 268 Bowman Ave., Merion Station. Pa.
Laws, C. R., 511 Leffingwell, Kirkwood 22, Mo. Lebid, J., 1088 Parkside Ave.. Buffalo 14, N. Y. Lehfeldt, H. J.. Bldg. 92. Rm. 226 OL. National
Bureau of Standards. Washington 25. D. C. Lenz, H. G.. 612 Home St., Winnipeg. Man.. Canada Lesko. N. J., NRL CBA. Chesapeake Beach. Md. Linden, A. E., 6738 Wyncote Ave., Philadelphia 38. Pa.
(Continued on page 108A)

1063

PROCEEDINGS OF THE I.R.S.

April, 1953

the p//ioneer 1 is d llI\eMader

·
OHNSONIvariable inductors
·

MOM%

PA/NORiAMIC I\S THE PI

in

the transformation of spectrum content

· · · known as the "Panoramic Method" by

/

tpihnretoodeunvctiiisnrugealeilsnepscetcrtouonmgiercnatpfsiheilcdu.ndeixscpellalyesd for

PANORAMIC LEADS the industry in

application requiring high speed spectrum or waveform analysis. Whatever your problem, a Panoramic Analyzer solves it quickly, accurately.

PANORAMIC leads again with 1

Signal Switcher--SWI Designed to apply alternately test and standard signals to Panoramic Sonic Analyzers. Enables frequency comparisons to within a fraction of acycle. Used with the G-2 Sonic Response Indicator, it facilitates rapid comparisons of the frequency responses of amplifiers, filters, transmission lines, etc.

To meet the needs of RF power equipment manufacturers, JOHNSON builds amost diverse line of variable inductors. These range From 3to 50 amperes current capacity, inductance to 300 microhenries in standard types. Characteristics of all models are: high frequency insulation grade L4 or better, low contact resistance, rigid construction. Two typical examples of JOHNSON variable inductors are:
224-2-1
Variable inductor For high power applications. Winding is I/2 " copper tubing rated to 50 amperes current. Inductance continuously variable to 16.5 microhenries. Spring loaded silver plated roller contact permits adjustment with full power applied. Insulators are glass bonded mica; cast aluminum end frames are slotted to minimize Eddy current losses. Overall dimensions: length 21 1/8", width 9", height 9". Available in eight standard models, maximum inductances 10 thru 110 microhenries. Variations horn standard units such as special inductances, dual inductors for push-pull applications can be readily furnished in production quantities.

· e · e
.·4 ·

Pancilyzor--Model SB-I2 Type T-100 Designed specifically for applications requiring extreme resolution or demanding measurement of levels of signals spaced very closely In frequency or widely divergent in amplitude.
· Maximum Sweepwidth-100KC · Maximum Resolution-10CPS · Sweep Rates-30cps, 5 cps,
1cps and Iscan in 10 seconds

Inquiries invited on

special Pano-

ramic Spectrum

:PANORAMIC Analysers WRITE TODAY FOR COM-

RADIO PRODUCTS. INC.

PLETE SPECIFICATIONS

AND PRICES ·

12 South Second Avenue. Mount Vernon. N.Y. MOunt Vernon 4-3970

229-201
10 microhenry rotary inductor for 100 watt
applications. Winding is #14 tinned cop-
per wire with variable pitch for efficient extended frequency range. Beryllium copper tension springs maintain rolling contact. Overall size: length 41 /2 ", width 21 /2 ", height 3". Other inductors in the same
series utilizing #12 and #16 tinned copper
windings, maximum inductance 37 to 300 microhenries.

In addition to these illustrated types, the JOHNSON line includes many other variable and fixed inductors for low, medium and high power applications. Fixed inductors are available with single or multiple windings, fixed or variable coupling windings and with electrostatic shields.
For further information on all types of JOHNSON inductors, write for catalog 973--yours on request.

E. F. JOHNSON COMPANY

CAPACITORS, INDUCTORS, SOCKETS, INSULATORS, PLUGS, JACKS, DIALS, AND PILOT LIGHTS

204 SECOND AVENUE SOUTHWEST

WASECA. MINNESOTA

PROCEEDINGS OF THE I.R.E.

April, 1953

107A

Try Remler for Service-Tested
"Hard-to-Get" Components

(Continued from page 1064)

Metal-plastic components designed and manufactured to order. Write for quot0. tions specifying electrical and mechanical character-
istics. Describe application. No obligation.

REMLER
TUBE SOCKETS
· STANDARD FOR 30 YEARS... THE BEST IN THE INDUSTRY
Heavy duty phenolic sockets with high current wiping action contacts ...for industrial, transmitter and test applications. Rugged. Years of tube insertions and withdrawals do not impair contact effectiveness. Black phenolic, low loss phenolic or alkyd.

Remler Company Ltd. 2101 Bryant St. San Francisco 10, Calif.

(.57mee ea" PIONEERS IN ELECTRONICS AND PLASTICS

In line with our specialization in wire for new applications, we produce wires of composition suitable for the manufacture of Transistors; including GALLIUM GOLD and ANTIMONY GOLD. These alloys have been made to fill a specific need arising from new developments in this field. Other wires we make regularly for similar application are PHOSPHOR BRONZE, bare or electroplated, and PLATINUM Alloys produced to meet rigid specifications of tensile strength, size and straightness.
Write for Latest List of Products
SIGMUND COHN CORP. 121 So Columbus Avenue ·Mount Vernon. N Y

Linker, C. L., 3628 Southwestern Blvd., Dallas 5, Tex.
Lofths, W. E.. 4454 N. Racine Ave.. Chicago 40, III. Lolass, A.. Jr.. 2493 St. Pierre Ave., Altadena, Calif. Losher, M. I., 10240-67 Dr., Forest Hills, L. I,
N. Y.
Lubin, E.. 2187A N. John Russell, Elkins Park 17, Pa.
Luty. R. C., Jr.. Apt. 0-2, 531 Kings Highway. Moorestown, N. J.
Manor, N. D., 403 W. Main St., Xenia. Ohio Marie, C. G., 88 York Rd., Lynn. Mass.
Mark, W. R., 440 E. Sharon Ave., Glendale, Ohio Marsland. J. W., c/o Marsland Engineering Co..
154 Victoria St., S., Kitchener. Ont.. Canada Martin, J. A., Jr.. 1904 Fairview St., Willow Grove. Pa.
May. J. C., 306 Kennebec St.. Washington. D. C. McCoskrie. D., 623 Westview St., Philadelphia, Pa. McFarland, D. J., 1055 Water St., Eau Gallie, Fla.
McFarlane, H. M.. Texas Forest Service, Lufkin. Tex.
McGregor, G. L., Lincoln Highway West, R.F.D. 3, Fort Wayne. Ind.
McGuire, T. B., Apt. 201. 210 Lynnwood St. Alexandria, Va.
McGuire, W.. 711 S. Front St., Hamilton. Ohic McKnight. V. J.. R.F.D. 3. Box N 177, New Bern.
N. C.
Mech. H. D., 54 W. Main St.. Corfu, N. Y. Memzies, R. W.. 64 Terrace Rd., Medford 55, Mass. Mennen, H., 3303 Harlem Rd., Buffalo 25, N. Y. Mikaelian, M., 318 Grand Ave., Dayton 5, Ohio Miller, A. M., 119 N. Saratoga St., Olney, Ill. Miller. C. M.. 103 Linda Lou Dr.. San Antonio 10,
Tex.
Mitchell. J. L., Massachusetts Institute of Technology. Digital
Computer Laboratory, 68 Albany St.. CambricIrt, Mass.
Monari, A. J., T. C. Wheaton Co., Millville, N. J. Monsees. F. G., 221-43-91 Ave.. Queens Village,
L. I., N. Y.
Moses. N. J., 144 Ringdahl Ct., Rome, N. Y. Murphy. E. F., 216 W. Rankin St., Flint. Mich. Nicholson, V., 1439 Lardner St., Philadelphia 24,
Pa. Nofrey. L. C., 3916 Carrington St., Oakland I
Calif.
O'Brien, J. F.. c/o Plastoid Corp., 5Old Rd., Hamburg. N. J.
O'Donnell, J. J., 56 Twin Lane N. Wantagh, L. I. N. Y.
Oister, G. K., 571 Lincoln Ave.. Pottstown, Pa Olsen, T. W.. 9225 Convent Ave.. Philadelphia 14,
Pa.
Oslake, J. J., 801 W. Ferry St., Buffalo 22, N. Y. Ozaki. G. K., 2122 Eby Ave.. Fort Wayne, Ind. Palmer, J. C., 40 Trumbull St., Xenia, Ohio
Parker, W. E., 54 Cottage PI., Long Branch, N. J. Parris, %V. J., 1I-A Brookwood Garden Apts., Bur-
lington, N. C. Patrick. D. J., 1804 Sixth Ave., Dodge City, Kans. Pawlowski. F. L., 8137 N. Keating, Skokie. Ill. Pearson, L.. 527 Jeanne-D'Arc, Montreal 4, Que..
Canada
Peters, J. C., Box 3431, USAFIT, Wright-Patterson AFB, Dayton. Ohio
Peterson, D. G., 695 E. First Pl., Mesa. Ariz, Petitto, S. D., c/o Mrs. Richards, 4045 N. Green-
view Ave.. Chicago 13, III. Pettersen, E. S., 673-85 St.. Brooklyn 9. N. Y. Phillips, A. H., 4453 Pelham, Dearborn, Mich. Pidgeon, R. E., Jr.. 206 Gelpi Dr., Lake Charles. La.
Polhemus, G. C., 431 Conshohocken State Rd., Cynwyd. Pa.
Porter, F. A., Page Engineers. APO 677, c/o Postmaster, New York. N. Y.
(Continued on page 1104)

108A

PROCEEDINGS OF THE I.R.E.

April, 1953

he FIRS and still the only R EADING ALL-BAND DIRECT
SPECTIUM ANALYZER TO 21 000 MCS
Polarad's Model LSA Spectrum Analyzer is the result of years of research and development. It provides a simple and direct means of rapid and accurate measurement and spectral display of an r.f. signal.

I· Continuous tuning.

Frequency marker for

· One tuning control.
3 · Resolution is 5KC when I dispersion is 5MC per inch II per sec.
· 250 KC to 25 MCS display at all frequencies.
· Tuning dial frequency accuracy 1f/r.
I· No Klystron modes to set.

measuring frequency differences 0-25 MCS. · Only four tuning units required to cover entire
range. · Microwave components
use latest design noncontacting shorts for long mechanical life. · Maximum frequency

I· Broadband attenuators supplied with equipment

coverage per dollar invested.

from 1to 12 KMC.

· 5 inch CRT display.

I. Where Used: Model LSA Spectrum Analyzer is a laboratory instrument used to
IProvide a visual indication of the frequency of distribution of energy in an r.f. signal in the range 10 to 21,000 MCS.

II Other uses are:
II. Observe and measure sidebands associated with amplitude and frequency modulated signals. 2. Determine the presence and accurately measure the frequency of radio and/or radar signals.
I 3. Check the spectrum of magnetron oscillators. 4. Measures noise spectra. 5. Check and observe tracking of r.f. components of a radar system. 6. Check two r.f. signals differing by a small frequency separation.

THE INSTRUMENT CONSISTS OF THE FOLLOWING UNITS:

Model LTU-1 RF Tuning Unit-10 to 1000 MCS.
Model LTU-2 RF Tuning Unit-940 to 4500 MCS. Model LTU-3 RF Tuning Unit-4460 to 16,520 Model LTU-4 RF Tuning Unit-

Model Model Model

LOU-1 LPU-1 LEU-1

15,000 to Spectrum Display Unit. Power Unit. Klystron Power Unit.

21,000

MU*

Write for Complete Details

100 METROPOLITAN AVE. BROOKLYN 11, N. Y.
Export Dept.: 13 East 40 Street, New York 16 N Y. Cable Address: "ARLAB"

PROCEEDINGS OF THE I.R.E.

April, 1953

109A

pereeetioe BY
At) It SCREEN PRINTING

FROM BLUE-PRINT TO FINISHED PRODUCTS.

200

·COMPC.IP. Ael Ale P1.1010GR AP1-1`1DEPARIMENI ·04161.1114G DEVI. COMPRISES ·141F..1 At. PREP AR A1101,1 a Se 01NG RADOM COMPOUND a 1-1.1M1NESCE.N1 MAIE.R1A1..

· A COPMPPO1C:A(I1 10 ONGOVERNMENI SPEC,S.

Aeggige0l1e0elilekeAtpe1P0gte&.I.E\B ._IS.e E&.\e 1S1SC1f,OltN0CD,0INACAIS.,SSS.\S

(I0

so,SE.ftY114G le.. P.VitC12P-fl b t.t.eceotec elouslies le MOSI Pelee ere OOEN SWiteele.E.PaOEINA\MNE.G1... BEG S PP,1 OFF

.,

PHOTO47C9HEMI"CAL PRODUCTS,

479NEW

N AVE NUE

YORK 91, N.Y.

INC.

NEW!

Tubeless Regulated Dual DC

Supply

for

Transistor Application

Model 110
Price $149.50
Features
V No Tubes-Long Life \/ Negligible Warm-up Time N' Dual Output-Positive or Negative \' Continuously Variable Outputs \' Output #1--Triple Range at 60
ma 0-1.0, 10, 100 v. \' Output #2 0-100 y at 60 nia V DC Impedance less than 100 ohms
Line Regulated 95-125 \/ Ripple Less Than 0.01% \i Moderately Priced
Order Now for Quick delivery or write for Bulletin B I.
Electronic Research Associates
Dept. I1, Box 29, Caldwell, N.J.

MODEL A-4
TIME DELAY GENERATOR
· A precision device for the generation of accurate and variable time intervals from .00001 to 10 seconds. Also available: Model A-2--.8 to 100,000 µs.
etttkeyeet Write for complete data: Our bulletins I-A-4 and l-A-2
ELECTRONICS CO.
3707 5, ROBERTSON BLVD., CULVER CITY, CALIF.

(Continued from page 108.4)
Powell. G. M., 74 Rebecca St., Shinnston. W. Va. Powers. W. J., 25 Abbott Pl.. Fall River, Mass. Rector. D. A.. 30 S. Old Glebe Rd.. Arlington. Va. Reed, G. W.. 319 Highland Rd.. Ithaca. N. V. Reynolds. R. N., Jr.. Box 162. Stony Brook. L. L.
N. Y. Richard, J. D.. Jr.. 531 S. Barrancas Ave.. Warring-
ton. Fla. Riley. J. H.. 3105 Amherst St., Dallas. Tex. Rime, J. A.. 150 S. Virginia Ave., Falls Church. Va. Robins. H. M., 700 Bittersweet Pl.. Chicago 13. Ill. Rodda. E. N.. 58381 West 87 St.. Los Angeles 4.5.
Calif. Rodgers. J. L.. 5707 Tilden Ave.. Apt. 6. Van Nuys.
Calif. Rogers. T. E.. 1102 Southland Life Bldg. Annex.
Dallas I. Tex. Rolfe. R. G.. 2105 Belvedere Blvd.. Silver Spring.
Md. Rousey, W. A.. 9444 Danby Ave., South Whittier.
Calif. Ruttenberg, S.. 561 Broadway, New York 12. N. V. Saari. V. R., 9 Irvington Pl.. Clifton. N. J. Semen J.. 228 Burlington Ave., Paterson 2. N. J. Savage. L. A.. 426 E. Genesee, Flint, Mich. Schafer. N. B.. 1208 Madison Ave.. Austin 5. Tex. Schneeberger. R. F.. 315-D Langfield Dr., Buffalo
15. N. Y. Scott, S. D.. Box 3068, USAFIT MCLI, Wright.
Patterson AFB. Dayton, Ohio Scott, W. W.. R.C.A.F. Station Clinton, Clinton.
Ont., Canada Seals, M. L.. 712 Strathcona St.. Winnipeg, Man..
Canada Seligman, J. M.. 3047 Kensington Ave., Phila-
delphia 34. Pa. Selover. E. E.. Box 3420, USAFIT. Wright-Patter-
son AFB, Dayton, Ohio Severance. F. D.. 714 W. Front, Burlington, N. C. Sheehan. J. F., 74 Victory Dr.. Niagara Falls. N. V. Sheldon. M., 64 West 91 St.. New York 24. N. V. Stretford, L. L., R.F.D. I. Middleport, N. V. Shenk. J. J.. R.F.D. 1, Northumberland, Pa. Siegel. H. A., 527 Peck Ave.. San Antonio 10. Tex. Silver. N.. 84 Bracewood La.. Stamford. Conn. Sindelar, F. J., Kimball Rd.. Poughkeepsie, N. V. Sippach, F. W.. 429 Wyoming Ave.. Maplewood.
N. J. Slocum, G. V.. Box 353, Shaw AFB. Sumter. S. C. Smith, C. C.. Sunset Crossing, Littleton. Mass. Smith, L.. 26-16 Union St.. Flushing 54. L. I., N. V. Spencer. P. L.. 85 Adena Rd.. West Newton 65,
Mass. Spencer. R. W., 411 W. Mt. Airy Ave.. Phila-
delphia 19, Pa. Spitler, M. E.. Jr.. 21 Bennett PL. Leominster.
Mass. Stanley. H. T., 62 Throckmorton Ave.. Red Bank.
N. J. Staples. R. L.. 28 S. Wood. Emporium. Pa. Staunton. J. J. J, 310 Wesley Ave., Oak Park. III. Stone. I. C., 128 Greenfield Rd.. Mattapan 26,
Mass. Studwell, A. E.. 77 Howard Ave.. Rochelle Park.
N. J. Taggart. C. E.. 101 Carpenter Ave.. Mt. Kisco.
N. Y. Tanielian. G., 3262 Overland, Los Angeles. Calif. Taylor, A. D., 324 S. Sultana Ave., Upland, Calif. Terrell, D. S., R.C.A.F. Station. Clinton, Ont..
Canada Thomas, C. P., Box 3288, USAFIT. Wright-Patter-
son AFB. Dayton. Ohio Thomas. O. D.. Jr.. do Mrs. Lura Mae Cooper,
2331 Cincinnati Ave.. Apt. 2, San Antonio 1, Tex. Tidd. T. J., 20 Briarcliffe Rd.. Glenolden, Pa. Tiffin, C. M., 25 Branch Brook Pl., Newark 4. N. J.
(Continued on page 1144)

110A

PROCEEDINGS OF THE I.R.E.

April, 1953

Top Service
IS ASSURED WHEN
YOU ORDER YOUR
RAYTHEON
TUBES
and JUNCTION TYPE
TRANSISTORS
FROM
DALIS
Metropolitan New York's Foremost Electronic Distributor
Immediate Delivery From Stock

PHONE: Algonquin 5-3000 WRITE or WIRE: Dept. IND TELETYPE: N. Y. 1-2482
H.L.DALIS
WHOLESALE DISTRIBUTORS ELECTRONIC EQUIPMENT
175 VARICK ST., NEW YORK 14

SERVING THE TRADE FOR OVER AQUARTER CENTURY

PROCEEDINGS OF THE I.R.E.

April, 1953

ulnion `rnd maintenanc

NOMY· ···

Mechanisms to 0 iodate components t so ific systems.

Adapter to tailor standard components to specific systems.

SUPPLY

ADAPTER

MECHANtSM

Corn' ete-lipof 60 and 400 cycle ifmplifiers and asSoceed power suppliesi6r servo motors in thel and 10 watt range. Others on special order.

uTnhiet sceormvpolestysetem

with chassis and shock mount.

...in advanced
automatic control systems, computers and instrumentations with

SMI's standard line of pre-designed electronic

plug-in packaged functions!

SERVOMECHANISMS, Inc., packaged function or "building block"

technique divides the systems' circuitry into basic circuits...

power supply, adapter, modulator, amplifier, positioning

mechanism ...and assembles them into standardized plug-

in, compact units. Standardization of units allows for mul-

tiple applications and combinations to effect desired

systems or instrumentations. Units plug into pre-wired

chassis and lock into position with quick-acting

fasteners. Maintenance becomes aplug-in or -out

operation ...This design philosophy provides for:

· Performance Reliability

· Installation Flexibility

· Ease of Maintenance · Interchangeability

Write for information on specific military and industrial applications.

SERVef:1- 1 fid- ISMS INC

POST AND STEWART AVES., WESTBURY, N.Y.

NEW CASSEL, N.Y.

EL SEGUNDO, CAL.

111A

COMPLETE CIVILIAN LINE
Exceptionally good delivery cycle on civilian orders due to tremendous mass production facilities.

TYPE C45-70
NEW HIGH DUALITY MINIATURIZED -DIME -SIZE - CIVILIAN CONTROL-Performanr· huir (quell target Types. TYPE 70, 3/4" diemeter variable tempesition resister. Wattage rating: .3 watt for resistances through 10,000 ohms, .2 watt with 350 volts maximum across end terminals for resistances over 10,000 ohms. Also available in concentric shaft tandem construction C45-70 as shown above.

rypf C2

PE C2-35

TYPE C2-25
ir\

rill GC-45, 15/16" diameter variable Inpesitiee resistor. Wattage rating. 2 wort for resistances through ,000 ohms, 1/3 watt for resistances or 10,000 ohms through 100,000 ms, 1/4 watt with 500 volts maxim across end terminals for resist.
ces over 100,000 ohms. Available is or without illustrated attached itch and in concentric shaft tandem estruction C2-45 as shown above.

TYPE GC-35, 11/8"diameter variable composition resistor. Wattage rating: 3/4 watt for resistances through 10,000 ohms, 2/3 watt for resistances
over 10,000 ohms through 25,000 ohms, 1/2 watt with 500 volts maximum across end terminals for resist-
ances over 25,000 ohms. Available with or without illustrated attached switch and in concentric shaft tandem construction C2-35 as shown above.

PE GC-252, 1 watt, I17/64" diameter variable wirewound resister. Available with or without illustrated attached switch and in concentric shaft tandem construction C2-252 os shown above.

Typical concentric shaft tandem with panel and rear sections operating separately from
concentric shafts (TYPE C45-70 ILLUSTRATED). Similar construction available for all military resistors.

-
YPE GC-25, 4 watt, 117/32" (limiter variable wireweead resister. Available with or without illustrated attached switch and in concentric shaft tandem construction C2-25 os shown above.

REPRESENTATIVES
Henry E. Sanders McClatchy Bldg.
69th & Market St Upper Darby, Penn,. Phone. Flanders 2-4420
W. S. Harmon Company 1638 So La Crenega Blvd. los Angeles 35. California Phone. Bradshaw 2-3321
John A. Green Company 6815 Oriole Drive Dallas 9, Texas

IN CANADA
C C Meredith iS Co Streelsville. Ontario
SOUTH AMERICA
Jose luis Pontet Buenos Aires, Argentina Montevideo. Uruguay Rio de Janeiro, Brazil Sao Paulo. Brazil
OTHER EXPORT
Sylvan Ginsbury 8West 40th Street New York It. N. Y,

ENLARGED SHAF7
END VIEW

NEW 38-PAGE ILLUSTRATED CATALOG -

an on

00

complete line of variable resistors for military

and civilian use. Includes dimensional drawings

of each resistor. Write today for your copy.

TYPE 45, (JAN-R-14, Type RVT) I4won,15/16" diameter variable composition resistor. Also available with other
special military features not covered by JAN -R-94 including concentric shaft tandem
construction. Attached switch can be supplied.

TYPE 35, (JAN -R-14, Type RV3)
I2watt, II8'· diameter variable composition resistor. Also available with other special military features not covered by JAN -R-94 includ-
ing concentric shaft tandem construction. Attached switch can be supplied.

TYPE 252,(JAM-it-it Type RATO) 2 watt, 1 17/64" diameter variable wirewound resistor. Also available with other special military features not covered by JAN -R-19 including concentric shaft tandem
construction. Attached switch
can be supplied.

TYPE TS, (JAN-R-11, Type RA30) (May else be used es Type RATS)
4 watt, 117/32" diameter variable wirewound render. Also available with other special military features not
covered by JAN -R-19 including concentric shaft tandem
construction. Attached switch con be supplied.

COMPLETE MILITARY LINE
Immediate delivery from stock on 189 types including JAN -R-94 and JAN -R-19
types of variable resistors.

TYPE 15, (Miniaturized)
I2 watt 70 °C, 3/4" diometer mini°.
turized variable composition resistor

TYPE 10
1watt 70 °C, 15/16" diameter variable composition resistor. Attached switch con be supplied. Also available in concentric shaft tondent construction.

UNPRECEDENTED PERFORMANCE CHARACTERISTICS
!socially designed for military communications equipment subject to extreme
temperature and humidity ranges. -55 °C to 150 °C...aridity to saturation.

TYP1 95, (JAN-R-14, Type RINI)
2watt 70°C, 11/8"diameter variable composition resistor. Also available with other special military features
not covered by JAN -R-94 including concentric shaft tandem construction. Attached switch can be supplied.

Yieciàion ifitzà4 Anduction q Vatiaélé Jiesiitoi4

MICROWAVE RESISIORS IatiAVE 'PRE II

SMALLEST RESISTOR AVAILABLE
(Ideal for Miniaturization)

TYPICAL APPLICATIONS

e Power measurement at any

frequency

e Matched terminations for wave-

eguides or coaxial lines Resistive power pickup loops

e RF pads or attenuators

e ee

Dummy loads Temperature measurements Impedance matching

TYPE R RESISTORS employ noble metal film deposits on specially selected heat resistant glass. FILM THICKNESS offers negligible skin effect, at microwave frequencies. POWER CAPACITY of 1 /4 watt provides high power handling ability. PHYSICAL STRUCTURE is ideally suited to impedance matching in standard coaxial line and waveguides. FINISH. Coated with aspecial silicone varnish to protect the film.

SPECIFICATIONS
Resistance: 50 ohms standard, other values on request.
Tolerance: 5% or 10% Wattage: 1/ 4 watt continuous duty
at 25°C Size: 1/16 inch diam. x3/16 inch long Terminals: Tinned sections 1/16 inch
long Film Length: Type R-063 -- 1/16 inch
Type R-093 -- 3/32 inch Temperature Coefficient:
approx. 0.0319 ohms/ohm/·C. Power Sensitivity: Approx. 10 ohms/
watt

TELEWAVE LABORATORIES, INC.

100 Metropolitan Ave.

· Brooklyn 11, New York

SQUARE PULSE GENERATORS for the MILLIMICROSECOND to MICROSECOND RANGE

For Nuclear Pulse Work, Radar, TV,
Wide Band Amplifiers, and in the design, calibration and servicing of fast electronic systems:

Membership
(Continued froui page 110A)
Tou, J., 163 W. Abbotsford Ave., Philadelphia 44. Pa.
Turner, H. C., Box 79-B, R.F.D. 9, San Antonio 7, Tex.
Uphoff, R. D., 18 Reid St., West End, N. J. Van Valkenburg. E. S., 808 Cornell Rd.. Ypsilanti.
Mich. Verrecchia, T. A., 540 Charles St.. Providence 4.
R. 1. Vilbig, J. L.. Jr.. 3887 Van Ness, Dallas, Tex. Vogt, W. M.. Jr., Box 756, Denham Springs, La. Walden, A., 824 Lovett Way, Pittsburgh 12. Pa. Walker, T. J., 2522 Collins Rd., Pittsburgh 35, Pa Walkling, R. W.. 8School House La.. Broomall, Pa. Warren. R. E.. 525 Edgeworth St., Middlesex, N. J. Waters, W. M., 6116 MacBeth Dr., Baltimore 12.
Md. Watts. W. W.. RCA Victor Division, Camden, N. J. Weaver, M. W.. 71 Matilda Ter.. Long Branch.
N. J. Webb, W. C., Jr., 332 Morton Ave., Dayton 10.
Ohio Weiland. G. H.. 77-43-166 St., Flushing. L. 1.
N. Y. Weir, D. B., R.F.D. 5. %Vinson Rd.. Welland. Ont..
Canada Wendlandt. C. W.. 3441 Wellington Rd.. Fort
Worth, Tex. Wetherbee. J. K.. 1807 Kings Ct., Columbus 12,
Ohio Wilber, B. E.. Rye Beach R.F.D. 1, Huron. Ohio Wilgus. D. S., 831 S. W. Sixth Ave.. Portland 4,
Ore. Williams, G. W., Jr.. 213-08 Northern Blvd., Bay.
side. I.,. 1., N. Y. Williams, G. P.. 2755 S. W. 58 Ave., Miami 44, Ha. Wilson, J. L., Box 50. Rivonia. Johannesburg.
Transvaal. South Africa Wisnowski, W. C., 3412 N. Avers, Chicago. Ill. Woldow, A. F.. 311 Cooper St., Camden 2. N. J. Woodman. A. J., 5149 N. Wolcott, Chicago 26. Ill. Wulkan, A. A., Box I, Kiryat Motzkin. Haifa.
Israel Young, R. L., Jr., 37-B Cedar Dr., Baltimore 20,
Md. Zahn, E., 25 Carroll Ct., Bridgeport, Conn. Zarbertski. E. I., 326 E. Union St., Nanticoke, Pa. Zaremba, C. J.. 99 Charles St., Floral Park. L. I..
N. Y. Zitovksy, S. A.. 378 Boulevard. East Paterson. N. J.

Model 100 Square Pulse Generator PRICE: $395.00 F.O.B. New York

NOW--A new Square Pulse Generator with a rise time of one millimicrosec-
ond (10' seconds) and a pulse width which can be varied from one mil-
limicrosecond to several microseconds provides the ideal test instrument for fast electronic circuits. Both positive
and negative pulses of a 100 volts maximum amplitude, into low im-
pedance (such as 50 ohm cable) are
generated; the pulse amplitude can be varied front 100 volts to .006 volts in 1
decibel steps by means of selector switches on the front panel. One, two.
or more pulse outputs, each of which can be individually attenuated and delayed are available in various models.

For further details, write for bulletin P-ht or contort our Engineering Division.

ELECTRICAL AND PHYSICAL INSTRUMENT CORPORATION

Sales and Business Office 25 West 43 Street New York 36, N.Y. Telephone: LOngacre 4-8510

Engineering Division 42-19 27th Street Long Island City, N.Y. Telephone: STillwell 4-63 89

News--New Products
These manufacturers have invited PROCEEDINGS readers to write for literature and further technical information. Please mention your I.R.E. affiliation.
(Continued from page 55A)
G.E. to Double Germanium Diode Production
The General Electric Co., Electronic Park, Syracuse, N. Y., will double its production of germanium diodes this year, to meet the rising demand of television manufacturers.
Their principal use is in home television receivers, where they perform as video detectors, according to James H. Sweeney, germanium products sales manager.
Each of the 6.5 million TV sets expected to be built by the industry next year will incorporate as many as three of the tiny devices.
(Continued on page 116A)

PROCEEDINGS OF THE I.R.E.

April, 1953

CLIWATE·PROOF PACKAGING

Here's a quick solution to
\Oki

g )\ee
CARGO PACKERS CLIMATE-PROOF PACKAGING
Meets all Specifications for Signal Corps, Navy and Air Force Shipments of Electronic Equipment with Facilities that include--
· SPECIAL PACKAGING EQUIPMENT
· EXPERTS IN MILITARY SPECIFICATIONS
· ECONOMICAL ASSEMBLY LINE METHODS
· FULL COMPLIANCE IN EVERY DETAIL
· COMPETENT CONSULTING SERVICE
NEW ILLUSTRATED BROCHURE explains in detail how Cargo Packers can economically handle all details of your military packaging problems. You save valuable plant space, costly equipment and the need for experienced specification packaging experts. Find out now, how Cargo Packers production line methods save you time, money, endless detail work, and costly errors. Request your copy, now!
CARGO PACKERS
INCORPORATED
73 RUTLEDGE STREET BROOKLYN 11, NEW YORK

triple threat
Changing temperatures, vibrations, and accelerations affect the operation of all instruments. In spite of these variables, our products produce the right answers because they are properly designed.
AIRCRAFT INSTRUMENTS AND CONTROLS
OPTICAL PARTS AND DEVICES
MINIATURE AC MOTORS
RADIO COMMUNICATIONS AND
NAVIGATION EQUIPMENT
Current production is largely destined for our defense forces; but our research facilities, our skills and talents, are available to scientists seeking solutions to instrumentation and control problems.

kollsman INSTRUMENT CORP.

EXPERTS IN CLIMATE PROOF PACKAGING

PROCEEDINGS OF THE I.R.E.

April, 1953

ELMHURST, NEW YORK · GLENDALE, CALIFORNIA · SUBSIDIARY OF Siaellaild COIL PRODUCTS CO, INC.
:

Further Proof of
Getting to the bottom of things

. .is most clearly demonstrated by what we are doing every hour of every day -- year in and year out -- to make a finer fixed CAPACITOR.

One of the many things you as users are interested in is the "LIFE OF THE CAPACITOR" under a multitude of operating conditions. We in the FAST organization have spared no expense to give you honest-to-goodness answers on this important factor in providing quality capacitors.

What follows is a summary of what we are doing to give you just that .

I: RESEARCH and DEVELOPMENT TESTS

II: PRODUCTION TESTS

AC and DC tests at various temperatures and voltages. 1--Investigation of Impregnants: (a) New impregnants AC--synthetic and natural oils. DC-- oils, resins and waxes. (b) Studies of impurities and additives. 2--Investigation of electrode separators and electrode materials: (a) Modified kraft papers--low PF varieties and sundry densities. (b) Films--re' ttecn.erated cellulose, polystyrene, teflon,"Mylar"·,

.4. Alternating Current 1--Heat runs on production lots--ultimate surface temperature rise. 2--Ultimate life hours of current production (periodic tests run).
B. Direct Current 1--Civilian Production: (a) ultimate life hours of capacitors taken from current production. (These test runs comprise over 1600 groups involving more than 16,000 units)

3--Number of groups tested: AC; over 800 involving more than 8000 units. DC; over 3300 involving more than 70,000 units. 4--Duration of tests: AC; many have been continuously under test for over 6 years. DC; many have been continuously under test for over 10 years. 5--Voltage range of tests: AC; 70 to 2400 volts at 60 and 400 cycles. DC; 140 to 44,000 volts. 6--Temperature range of tests: AC; Room to 130°C. DC: --55°C to +150°C.
Capacitor Specialists For Over A Third of A Century 3171 North Pulaski Road, Chicago 41, III. "WHEN YOU THINK OF CAPACITORS ... THINK FAST"

(b) Ultimate life hours of capacitors after being stored in cartons from 1 to 24 months under normal variations in humidity and temperature. (These test runs comprise over 230 groups involving more than 2300 units) 2--Military Production: (a) Test to applicable specifications (Jan. C-25; Jan. C-91; U. S. Army 71-1667; Etc.) (b) These test runs comprise over 3300 groups involving more than 19,000 capacitors.
Please note Carefully: at least 80% of the 115,300 capacitors included in the above tests were tested to destruction at voltages from 11/ 2 to 4 times rated and at maximum rated--or in excess of--operating temperatures. Many outside this group have not failed to date. Importantly too, this is a continuous policy of the company in sustaining our testing program throughout every day --year after year.
So with pardonable pride may we suggest QUALITY CAPACITORS is more than a "catchphrase" as applied to the FAST organization ... and another lank in the chain of GETTING TO THE BOTTOM OF THINGS? *Du Pont trade-mark for Polyester Film

News--New Products
These manufacturers have invited PROCEEDINGS readers to write for literature and further technical information. Please mention your I.R.E. affiliation.
(Continued from page 114A)
Sweeney said the recent allocation by the Federal Communications Commission of 70 new TV channels in the ultra-high frequencies is largely responsible for the production increase. Tuners and converters to permit reception of the uhf channels each require one or two germanium diodes, he explained.
Nearly every TV set now manufactured for receiving very-high-frequency stations (channels 2 through 13) also incorporates one of these devices.
Power Supply
A new and highly precise high-power direct-current source, designed for digital and analogue computers, business machines and other complex electronic devices, has recently been developed by Inet, Inc., 8655 S. Main St., Los Angeles 3, Calif.

.S.W .HITELOX VOLTAGE RESISTOR

(V2 Actual Size)
4 watts ·100 to 100,000 megohms

Developed for use as potential dividers in high voltage electrostatic generators, S.S.White 80X Resistors have many characteristics--particularly negative temperature and voltage coefficients --which make them suitable for other high voltage applications.
They are constructed of amixture of conducting material and

binder made by a process which
assures adequate mechanical strength and durability. This material is non-hygroscopic and, therefore, moisture-resistant. The resistors are also coated with General Electric Dri-film which further protects them against humidity and also stabilizes the
resistors.

WRITE FOR BULLETIN 4906
It gives complete information on S.S.White resistors. A free copy and price list will be sent on request.

I I
116A

cze

mre

01111011111111111MAIL ouvuonoos
Dept. GR 10 East 40th St. NEW YORK 16, N. Y.

WESTERN DISTRICT OFFICE: Times Building, Long Beach, Calif.

This magnetic amplifier-selenium recti-
fier dc power supply, provides dynamic regulation of better than 0.2 per cent with wide load and alternating current line changes. Steady state regulation proved to be less than 0.15 per cent from no load to full load, with ±10 per cent ac line voltage. RMS ripple can be filtered as low as 0.01 per cent; with 0.5 per cent as standard.
[net's precision power supply is said to require about half the space of many types of equipment with comparable performance, and is housed in a single compact cabinet, or can be built with dimensions to customer's specifications.
The selenium rectifier-magnetic amplifier design eliminates thyratrons or ignitions. Thus the equipment is designed to require the minimum of maintenance and parts replacement. Because of its high efficiency (approximately 75 per cent), the unit has sufficiently cool operation to reduce refrigeration requirements in officeinstalled computers.
(Continued on page 118A)

PROCEEDINGS OF THE I.R.E.

April, 1953

need relays

ENGINEERS...TECHNICIANS! ..here is your

Potter & Brumfield is your
BEST SOURCE for
CUSTOM-BUILT
RELAYS

here's why!
Design
Fast, accurate development of relays for every electrical and electronic application to meet the most exacting military or industrial specifications.

Engineering
Extensive research, laboratory and model shop facilities available to help solve design engineers most complex relay problems.

Manufacturing

El. ·

. Three large, fully

equipped plants

geared to meet today's rigid

production requirements ...

single shift capacity of 10,000

relays per day!

· Samples, Recommendations and Quotations on Request.
eP & B Sales Engineers in Principal U. S. and Canadian Cities.
· Write for Master Catalog Showing Full Line of Basic Structures.
· Standard Relays Available At Your Electronic Parts Distr.butor,

Dip Meter
IC -i del 6NO2 LOW PRICE: $ 39 N7E5 T

VERSATILITY, COMPACTNESS, QUALITY

Few instruments will prove so handy in so many ways as this versatile B&W Model 600 Dip Meter! Ideal for lab, production, service or ham shack use, it provides a quick, accurate means for measuring resonant circuit frequencies, spurious emissions and many other tuned circuit characteristics. Shaped for easy use in today's compact electronic assemblies, highly sensitive and accurately calibrated, it incorporates many features previously found only in higher-priced instruments. You'll find dozens of uses for it as ...
A Grid Dip Oscillator for determin-
ing resonant frequencies of tank circuits, antennas, feed line systems, and parasitic circuits; align-

ing filters and traps; peaking coils, neutralizing and tuning transmitters before power is applied.
An Absorption Wove Meter for accurately identifying the frequency
of radiated power from various transmitter stages: locating spurious emissions causing troublesome TV and radio interference, and many similar uses.
An Auxiliary Signal Generator providing a signal for tracing purposes and for preliminary alignment of receivers, converters, and I-F stages.
An R-F Signal Monitor for audible observation of hum, audio quality, and other audible characteristics of radiated power.
For Capacity, Inductance, and "Cl" measurements in conjunction with
ot her components of known value.

e TECHNICAL Covers 1.75 to 260 mc. in 5bands.
Adjustable sensitivity control.
Size 3" x 3" x 7". Weight 2 lbs. Handy wedge-shape for easy access in hard-to-get-at places.

FEATURES

Monitoring jack and B4- OFF switch.

Rust-proofed chassis, aluminum

ecase. Built-in

power

supply

for

110

volts A.C.

Sold by leading distributors throughout U. S. A. and Canada Data bulletin sent on request.

PRINCETON,

INDIANA

Export: 13 E. 40th St., N. Y., N. Y.

PROCEEDINGS OF THE I.R.E.

April, 1953

BARK 8É VVILLIAMS0111INC.

237 Fairfield Avenue

Upper Darby, Penna.

1I7A

ir cmoonttorrosl

10 Watt --,-.-.elON,·,.....,,

for extremely low inertia and high frequency response
HIGH VOLTAGE MOTORS

Rotor Inertia 0.23 oz-in.' Weight 4.3 lbs.

60 Cycle, li2-5-10 watt models Designed specifically for electronic systems-- operate directly in the plate circuit of a vacuum tube amplifier.
LOW VOLTAGE MOTORS
60 and 400 Cycle, 21/ 2 -5-10 watt models Recommended for normal two-phase applications.
advantages

Write for Descriptive Brochure about all
Ford Control Motors.

· Linear torque--voltage characteristics · Linear torque--speed characteristics · Withstand continuous stalling · High torque efficiency · Flexibility of mounting

FORD INSTRUMENT COMPANY
Division of The Sperry Corporation
31-10 Thomson Avenue, Long Island City 1, N. Y.

COILS to exact specification for every requirement 4;4' ott esk

News--New Products
These manufacturers have invited PROCEEDINGS readers to write for literature and further technical information. Please mention your I.R.E. affiliation.
(Continued frem: page 114.4)
New Set Screw
Set Screw & Mfg. Co., 422 Main St., Bartlett, fi., announces anew type of set screw, the "Nu-Cup."
The cup point of "Nu-Cup" is designed so that the user obtains increased holding power with the same amount of setting torque. The diameter of the cup circle is larger than that of the standard cup point, which makes afuller contact possible and adeeper impression into the shaft, offering greater resistance to reversal, with the same setting torque. "Nu-Cup" distribution pressure is spread over a wider area, 20 to 25 per cent greater than conventional set screws.
"Nu-Cup" Set Screws are particularly suited to applications in which the shaft is soft, or is small in relation to the contact arc of the screw cup. The new set screws are made of an alloy steel, specially selected for hardness and offering exceptional capacity for pressure. They are available in slotted headless and slabbed type set screws only. A catalog is available by request.

AI>

Rotary Exhaust Tube Sealer
Consolidated Vacuum Corp., Rochester

4, N. Y., formerly the Vacuum Equipment

sr: Ite. QUALITY BUILT COILS FOR RADIO, FM,

Department of Eastman Kodak's Distillation Products Industries, announces the
availability of aradically new high vacuum,

TV AND- GOVERNMENT APPLICATIONS

high speed, exhaust and sealing machine for miniature and sub-miniature electron

tubes.

Uniform high quality, fast delivery and low cost have made
Fugle-Miller coils the choice of many leading manufacturers in the radio and electronics industry. All types are supplied including Universal, Bank Wound, Universal Progressive and solenoid coils. JAN specifications are our specialty. Call, wire or write today for prompt quotations

There is no traditional slide valve at the center of the machine through which
the tubes are vacuum pumped. Rather, pumping is accomplished by an easily demountable packaged unit consisting of mechanical pump, diffusion pump, valves, and compression port. This unit will pro-

ADDRESS INQUIRIES TO DEPARTMENT P-4

duce apressure of 1micron or lower at the

FUGLE-MILLER

port in the positions immediately ahead of the tip-off.

LABORATORIES

Also, the machine is not indexing, that is, there are no starting and stopping mo-

MAIN STREET, METUCHEN, NEW JERSEY

tions. Once started up, the turret turns

^

Telephone: Metuchen 6-2245

(Continued on Page 120,4)

118 \

PROCEEDINGS OF THE I.R.E.

April, 1953

e\\\\\\1111/11////
WHERE RESISTANCE TO HIGH AND 1..OW IEMPERATURES
IS VITAL'-'3°c

BALLANT1NE
STILL THE FINEST IN ELECTRONIC VOLTMETERS

60 c

INSULATED HOOK-UP WIRE

· FUNGI
· ABRASION
· CHEMICALS
"Surflene", extruded monochlorotrifluoroethylene, has high insulation resistance, dielectric strength and outstanding resistance to heat, abrasion, most chemicals and concentrated acids, including fuming nitric acid. It is non-inflammable and inert to fungi. It is especially designed for hermetically sealed and water-proof equipment and for high temperatures encountered in power supply and continuous duty apparatus. Also available in multiconductor cables.
"Surflene" is available in thirteen colors -- red, orange, yellow, pink, light and dark green, blue, gray, tan, brown, black, white and clear.
Write our Engineering Service TODAY for technical assistance.

4.57 /1 ,49)1ZenadMFG CO

199 Woshtnglon St

8oston 8. Moss Plant Cl,nlon Mots

Eng ,

d Wore ond Coble lot lb, Elecnon, nncl

Ballantine Model 300
SENSITIVE ELECTRONIC VOLTMETER
Featuring alogarithmic
Voltage Scale and Uniform Decibel Scale
PRICE... $200.
· Measures 1millivolt to 100 volts over afrequency range from 10 to 150,000 cycles on asingle logarithmic scale by means of a five decade range selector switch.
· Accuracy: 2% at any point on the scale over the ENTIRE RANGE. · Input Impedance: 4 megohm shunted by 30 mmfds. · Generous use of negative feedback assures customary Ballantine stability. · Output jack and output control permit voltmeter to be used as aflat high gain
(70DB) amplifier. · Available accessories permit range to be extended up to 10,000 volts and down
to 20 microvolts. · Available Precision Shunt Resistors convert voltmeter to microammet,er cov-
ering range from 1to 1000 microamperes.
For additional information on this Voltmeter and Ballantine Battery Operated Voltmeters, Wide-Band Voltmeters, Peak to Peak Voltmeters, Decade Amplifiers, Inverters, Multipliers and Precision Shunt Resistors, write for catalog.
BALLANTINE LABORATORIES, INC. gli)
102 Fanny Itoad, Boonton, N.J.

PROCEEDINGS OF THE I.R.E.

April, 1953

I 19A

What is your Delay or Regulating Problem?
For the most effective solution use the
SIMPLEST, MOST COMPACT MOST ECONOMICAL HERMETICALLY SEALED

DELAY RE LAYS THERMOSTATIC

..c...,"....t.Z.I.deate.r· Air

AMPERITE. DELAY 4 RELAY
ill Ii
STANrs..Anr,

Provide delays ranging from 2 to 120 seconds.
· Actuate