ii-kteee .y. vuf .;Yeelnece.e.;: ,G.e ...

ii-kteee .y. vuf .;Yeelnece.e.;: ,G.e;:e-Y- ....,, ,.. «.4.,*jr; ?.,,e,-.,' :ez.u ..e. • I.. ,t ,,,. - „, ,,...)0 ,

PDF Electronics-1968-04-15
t-it.i.lmt.ei-l1kto·t ...(iSt t·.·.·. t·\,*.`a..;

· . .t ,. I.... . I,. ·-· I a-4 .... · ',re 0.9.9.9.11 0

· ·'10.· 0 e ..*:. · · ..e1,0. .0 · 9 , *

·,.......... up* · · 0 ..······· g

t 1

. (:·10d11f.·... 11t "·"0. I4..*··.··g0fl»,f..4.a·

·······-, ··,,..4 ., .
'* " " . " ·0). . 9 r e = ·ur ^·· 5 · · * · · · tit

a'-ir. ·R·etdrg

4. .4

·· · · · .r.: .

...1:, ··· ·· ···92,; ··,...,..,... e.a ...,...r.,...,.1..!. ··· ·." · ··· · ·.·. · · · · ···!.1.· .·....

ites10..···· ·
194`. ' 9 · 11. ·

· ., . ·

.,

·

·

· ·

·

· ·

·

· ·

······· · · · · · · : · · · ·.· .4>e'lee·orerro, .

· ·.: . ·· ....

·.·.·4

·;·: .

····"Irt · ! · · · · · · t · · · · · - ···:· ".

-.0.8 · . . e'e r o e 0.0 6 . 0 · · · go . . ... , >

. . .-. . .- · · 1. ·r·

.

· . · . · · · · de · . 0 f> · .0 . 0.0...... . . . · · .. 4, · s . · e e . .." .d....f.1.01, ·. · · · · · · · 4 rr · · ·: jt. f.········ · · · ...· ··· · · · ·.
11.· · · f· ·.·.·.·.·.f·f···f··.·..

ta

P't

· 6.1o · .,ie°2.1..·.·0.·,'.I.r.·°.

······ ...*.t.o· -.

11.7,.'·

v.40.'1.o/.g_4o. ot1

···· 4?>II.f.,o.o,l0.e,-·.,,'te,,,':1...*eft-'ze,,l,f.,,.u..).0.e,·....l-,'oeee-·. ·.

'· It14

*e et····`· .1. ··Sve .,

· .o ;1.0· #, · .1

4····· 3. · · j A · · · .t.i..

f · 1 e li 1°.,,.1 .10 .11`

. · · 0.

.0..4074 :#1.

04r#I6.00l.e:.44er`,4,,i'

' ·110 '01 · **··

`.4" ·1...4i,e0*, \ "1 ' · ,, ...,·,4 ,··········

...0. . .·. · 4.:/1l·eti'tf»·I .'f".'.ee·le·le·,·Y·i;e·'.·1 0.·:;.·-.

· · "0;

10'flot .·.1····

· ·-·.· · ..... · · .., ,, · . · ..* 2,-* 49,9 a * 4 ····· Prdt ·

·

·.5!..k . -·
.. '444¡·e ··r ··t .4i . orii

.11.1r. .00,····11,..g.r. ...;4.,

.1..............e.e...,... ...la.

·

o.·······_*.14.1/.4.f.,4...·.e .. , ·-:4.! .

········.* ..i.oreg*.·.4.f.··er' .'age. .·.4.·'

.I ..**14t*, rt_2 ,1 "-f L'

*re* º e e 1 .2 r..." ..-·

V VI

Qçt·"' '4 i'", ''" "4

1P.T... . est2v.,·e ···

,,,,,y ; ··3 Oil:, 4.-42 Ite ei*. ,Çjg
14 d-· 4 · de o*

.."

· tbo-'····-·0")

1.....·. ··,e...'c..e..,:.,,iei:-,.k...t.e;e.e;.«...4y:..,*;j.v:r;-.u-f, ...;.Yee'eel.n.ec*e-.e..';:'.',,i%·47..e;1:Pe·-4Y- · '

·.9

' ' .1104..'

;*.*. ..;116 ,e,';i:i;.$ %..ki.·.·.;..!,

. .,·...* r *

é..e.9· eé·k e e e e

e

' ·

...· 1.,p ele.7%

:-e.e.i!'4i: :0e.; :44¡ .r...i...e....0. 1...; ,

· · ·

- .-"...' !,6,41 '.· ··

* · '

· * .'lie.;:--fli:;':7::: ;e: t e" i.i . " di; ;1;e;

·

··'ill · sokai.1,..·· ·.;ç.;...i....r..;·...;.Yr..i ... .

'4*;!ig·ti1t Je.·'i.17·'··9 "·*".e4",.4"." ...e1 V.. ..4.91··".9e.verer Jr.r.I.

.V , ;./.. re.9...19,21. 9:9e.

.1 .· ir......·........»...·······:oef

.1..e .47;·'J'"1,.e"1e>· ele9evl1t:;,vteelfleI*IY,1,·.·*..

4.·:4..· ....

·

·

.....

·e?,i:ek·

ele 0070'* ". -

.....;. .....'eeieei

· ·,`m···. 'r-
ef-4 irFeer ·0 4 4 '
,;;

· ···.. ·'e.g..'.t...*·,······ ·-.......··
..f.f.i.11 /.71.01.11.1.;,i, .,. .9 1.:··

':'

- .. ···· ··e.··············.· '·· ;.q·r;··.·.;

9. .

. .f

é

·

,...,'.'

·,?;,...· .

.... . ·,.....-. · .-'·i'4!;

·
· r

0e ;deokkkale :it? 1:eil el:gtaMeele

eeiT. ·- >fer,A*.*'..

0e· :...,..0%. ...-. 1.;07116

....7.;......;.·.:..1..7....7.74tit-.. los

ti.e·o.o.411.0,

'

· ·



e * .......

.

4 tr

i... · ' ' ile-e;19,-Je9-;-.. ·do 1' t t .,0.0 .,...e...,

·

···.··.·

*;··.··-··· ······· ··

·.·

·.· .·

·.·...:·.·;· ··········.t. +.4 .·

q.
·.·

·.·.9.M.10......9.·.· · ···· ·· ······ ·.9..· ,,

.· ...· .9

40:i4 .·

'o.r.-v.e..i...l,.e.t· ·:V*'.,.ge·-i·-l·l-*.4 _. .,

,.1....

et·· -.4 I· ii-e-.-..i..

;.; "0¡51;:;;i`4"ill ).;?

.4.

0...010

·

9e:e

·"'re> UietkI14
·C·t°

1.01..ar 0 ;11101.1eK· .
High and Low pass

.11.ILIZZO

Me

Band Pass Minimum (26%) and Octave Bandwidths

Band reject, "Null", and various ratios of high-to-low cutoff

1952 Universal Filter ... $950. in USA

Precision in a variable filter

You don't have to sacrifice precision for the versatility of a variable filter. The new GR 1952 Universal Filter gives you sharp cutoff-rate, flat pass-band filtering with a unique selection of operating conditions.

The 1952 offers four switch-selected filtering modes: low-pass, high-pass, band-reject, and band-pass. High and low filters are fourth-order Chebyshev approximations with ±0.1 dB pass-band ripple and initial cutoff rate of at least 30 dB per octave. Since all switching is done within the instrument, these fine characteristics are maintained in all modes and at all frequencies from 4to 60,000 Hz.

For convenience and accuracy in bandpass and band-reject operations, the

Circle 900 on reader service card

high and low filters can be gang-tuned (with afront-panel switch) to maintain constant-percentage bandwidth. Minimum bandwidth in the band-pass mode is a mere 26% of center frequency (nearly 1/3 octave), and a "null" (infinite attenuation) characteristic is provided in the band-reject mode. For complete information, write General Radio Company, W. Concord, Massachusetts 01781; telephone (617) 369-4400; TWX 710 347-1051.
GENERAL RADIO

· · · ··

· ·

· · ··

· ·

·

· ·

· · · ··

·· · ·

·

·· · · ·

· · ·· ·

·

·· · ·

· ·· · ·

·

·· · · ·

·· · ·

·

·· · · ·

· · ·· ·

·

·· · ·

············································ · · ·· · · ··· · · · · · · · · ·························· · · ·· · · ·· · · · · ························ · ·· · · · ·· · · · · · · ·· · · · ·· ·

Ill

I II

I

III II I

I

III

I I II I

I

I 5 o C- 4 I 9

1 +

7 7 4 (3

5 4

+6203 I I

+ 6'

r..) ! 6 3r 9

+7105 2 0

+ 7 G I 696

+721742

Go 9 4 4 -)' ,) +630792

+594 70 3
+54 7 29 0

+ 4 9 5 2 7 4-

(.71 CJ1 (ji

(ji (J1 (j1 (.0 (51 Cl

(j1

The perfect data acquisition system:

HP has exactly what you want ... at the price you want.
Hewlett-Packard's data acquisition line spans the complete capability spectrum--all with off-the-shelf availability. From inexpensive data systems to on-line data reduction-- and everything in-between. Your standard system is tailored to your own specific measurement needs. No costly special engineering before you take delivery It sfieldproved, and the safest buy in

the industry. Prices range from $8,000 to $47,000.
The popularity of the HP 2010 Series demonstrates the flexibility of HP data acquisition systems; over 500 in use today. The new 2012 Series now adds unmatched speed, accuracy and ncise immunity to the HP line. HP systems offer up to nine different output devices, including printers, typewriters, tape and card punches and magnetic tape recorders.

HP also has combined a measuring system with an HP computer in the standard 2018 Data Acquisition Systems. These systems give you full control of your measurements, with on-line, real-time answers.
Looking for the perfect data acquisition system? You can save time and money by calling your local HP field engineer or writing Hewlett-Packard, Palo Alto, Calif. 94304; Europe: 54 Route des Acacias, Geneva.

Electronics April 15, 1968

HEWLETT ilk PACKARD

06809

Circle 1on reader service card

1

These ABC's spell more log converter performance.

A.
0.5 Hz to 100 kHz frequency range
B.
80 dB dynamic range
C.
True RMS

You get more with the Hewlett-Packard 7562A Logarithmic Converter than with any other instrument of its kind. It provides DC logarithmic voltage output from AC or DC input signals, with 80 dB dynamic range, true RMS detection for increased accuracy and unprecedented 0.5 Hz to 100 kHz frequency coverage, in three ranges. Two input voltage ranges 1mv-10 V or 10 mv-100 V. Fast response to 2/Is DC rise time and 60 dB/sec AC slewing speed.
The 7562A is ideal for a wide range of demanding

applications such as gain-frequency plotting with X-Y recorders, vibration analysis and semi-log or log-log plotting. Reliability is assured with rugged, compact, solid-state construction (including use of IC's). Use with scopes, X-Y and strip-chart recorders. A perfect companion for the new HP 3305A Logarithmic Sweep Oscillator. Price: $995.
For more information, call your local HP field engineer or write Hewlett-Packard, Palo Alto, California 94304; Europe: 54 Route des Acacias, Geneva.

HEWLETT L11i) PACKARD big

GRAPH IC

RECORDERS

2

Circle 2 on reader service card

11704
Electronics lApril 15, 1968

Electronics Volume 41, Number 8

April 15, 1968

News Features

Probing the News

157
163 171

Electronic traffic control
Simulators set to take off Navy drafts standard hardware

Electronics Review
45 Integrated electronics: Military cool to plastic IC's; Motorola readies fast line of IC's; Unpackaged chips business picks up
48 Instrumentation: Monsanto designs
instrument with solid state display; New way to test crystals 50 Medical electronics: Automatic EKG machine 52 Advanced technology: Tunable laser 54 Communications: Television via laser 56 Consumer electronics: Radiation dangers 60 Military electronics: TFX woes 63 Industrial electronics: Security guard 64 Manufacturing: No computer for IC processing 65 For the record

Electronics Abroad

275 276 277 277 277
280

Great Britain: Coils on track control trains; Laser simulates tank gun
West Germany: Kibitzing capsule carries electronic equipment
Canada: Government slates domestic communications satellite Soviet Union: Russians near mass
production of integrated circuits Japan: Radio-controlled bulldozers; Canon calculator has American-made
IC packages Italy: Telephone monitor cuts off
long-distance calls

New Products

193 206
206 210
215 215
218 223 223
225 228 231 231 235
237 237
240 243 243
246

Punched cards on the ropes? Components review
Connectors for flat cable Simpler wire-wrapping panel
Subassemblies review Wang offers desk calculator
Buffer handles fast data Instruments review
Linear IC tester checks 22 values
Data recorder is portable Wattmeter has high accuracy Industrial electronics review Controller for special uses Servo recorder built to last
Microwave review Flexible cable replaces waveguide
Magnetron for cool ovens Semiconductors review
IC requires one power supply
Diode sensitive to magnetism

Title R registered U.S. Patent Office; copyright 1968 by McGraw-Hill Inc. All rights reserved, including the right to reproduce the contents of this publication, in whole or in part.

Electronics April 15, 1968

Technical Articles

Advanced 92 technology

Setting the stage for flat-screen tv Experimental color set converts standard
signals with pulsewidth modulation Satoshi shimada, Sony Corp.

Circuit design 104 Designer's casebook ·Gate-to-source resistor stabilizes FET
regulator ·Power transistor's r-f gain
measured by brief pulse ·Amplifier flattens ripple
in d-c regulator

Design theory 108 Narrowing the margin of error Minimizing common-mode deviations of data amplifiers by combining op amps Robert I. Demrow, Analog Devices Inc.

Industrial 119 electronics

Saving money on data transmission as signals take turns on party line
Single two-wire cable connects all stations of acontrol or monitoring installation James W. Cofer Jr., Georgia Institute of
Technology

Computers 124 FFT--Shortcut to Fourier analysis Mathematics yields faster ways to extract information from complex waveforms Richard Klahn and Richard R. Shively, Bell Telephone Laboratories

Instrumentation

130

Making it in pictures Electric field intensity can be mapped on pre-sensitized Polaroid film Keigo lizuka, Harvard University

Communications 133 Airborne military transceiver finds room in crowded spectrum Artful design keeps intermodulation distortion low in 280,000-channel unit LP. Magasiny, RCA Defense Communications Systems

Departments

4 Readers Comment

25 Electronics Newsletter

8 People

67 Washington Newsletter

14 Meetings

254 New Books

16 Meeting Preview

258 Technical Abstracts

23 Editorial Comment

262 New Literature

267 Newsletter from Abroad

3

Electronics

Editor-in-Chief: Donald Christiansen

Associate managing editors
Technical: Stephen E. Scrupski News: Robert Henkel Copy: Sally Powell

Senior associate editors Joseph Mittleman, Harry R. Karp

Department editors
Avionics & Space: Alfred Rosenblatt Computers: Wallace B. Riley Communications: William Bucci Consumer electronics: John D. Drummond Design theory: Joseph Mittleman Industrial electronics: Harry R. Karp Instrumentation: Carl Moskowitz Military electronics: Richard Gundlach Solid state: Mark B. Leeds

Section editors Electronics abroad: Arthur Erikson Electronics review: Stanley Zarowin New Products: H. Thomas Maguire,
William P. O'Brien Probing the news: Eric Aiken
Assistant editors Stephen Wm. Fields, Peter Schuyten, James Kirby, Owen Doyle

Regional bureaus

Domestic

Boston: James Brinton, manager; Robin Carlson Los Angeles: Lawrence Curran, manager; Burton Bell New York: Howard Wolff, manager San Francisco: Walter Barney, manager; Peter Vogel Washington: Robert Skole, manager; William D. Hickman, Paul Dickson

Foreign
Bonn: John Gosch London: Michael Payne Tokyo: Charles Cohen

Copy editors James Chang, Frederick Corey, James Darby, Larry Miller

Graphic design Art director: Saul Sussman Assistant art directors: Ann Melia, Valerie Betz Production editor: Arthur C. Miller
Editorial secretaries: Claire Bench', Lynn Emery, Kay Fontana, Patricia Gardner, Lorraine Longo, Barbara Razulis, Frances Vacca
McGraw-Hill News Service Director: Arthur L. Moore; Atlanta: Fran Ridgway; Chicago: Bruce Cross; Cleveland: Arthur Zimmerman; Dallas: Marvin Reid; Detroit: James Wargo; Houston: Robert E. Lee; Los Angeles: Michael Murphy Pittsburgh: Louis Gomolak San Francisco: William F. Arnold Seattle: Ray Bloomberg; Washington: Charles Gardner, Daniel B. Moskowitz, Herbert W. Cheshire, Seth Payne, Warren Burkett, William Small
McGraw-Hill World News Service Bonn: Robert Dorang; Brussels: George Williamson; Hong Kong: Wes Perry; London: John Shinn; Mexico City: Gerald Parkinson; Milan: Ronald Taggiasco, Jack Star; Moscow: Howard Rausch; Paris: Robert E. Farrell, Peter Kilborn; Rio de Janeiro: Leslie Warren; Tokyo: Marvin Petal
Reprints: Susan Nugent
Circulation: Milton Drake

Publisher: Gordon Jones
Electronics: April 15, 1968, Vol. 41, No. 8
Published every other Monday by McGraw-Hill, Inc. Founder: James H. McGraw 1860-1948. Printed at 99 North Broadway. Albany, N.Y. 12207: second class postage paid at Albany. N.Y. Executive, editorial, circulation and advertising addresses: McGraw-Hill Building, 330 W. 42nd Street New York. N. Y. 10036. Telephone (212) 971-3333. Teletype TWX N.Y. 710-5814235. Cable address: MCGRAWHILL N.Y. Subscriptions solicited only from those professionally engaged in electronics technology. Subscriotion rates: qualified subscribers in the United States and possessions and Canada, $8.00 one year. $12.00 two years. $16.00 three years; all other countries $25.00 one year. Non·qualified subscribers in the U.S. and possessions and Canada, $25.00 one year; all other countries $50.00. Air freight service to Japan $50.00 one year. Single copies: United States and possessions and Canada, $1.00; all other countries, $1.75. Officers of McGraw·Hill Publications: Joseph H. Allen. President: Bayard E. Sawyer, Executive Vice·President; J. Elton Tuohig. Senior Vice-President·Operations; Vice Presidents: John R. Callaham, Editorial; John M. Holden. Marketing; Paul F. Cowie. Circulation; Angelo R. Venezian, Production; Jerome D. Luntz, Planning & Development; Robert M. Wilhelmy, Controller. Officers of the Corporation: Shelton Fisher. President and Chief Executive Officer; John L. McGraw, Chairman: L. K. Goodrich. Executive Vice President: R.E. Slaughter, Donald C. McGraw. Jr., Senior Vice Presidents; Daniel F. Crowley, Senior Vice President and Treasurer; John J. Cooke, Vice President and Secretary.
Toiftltehis pruebgliisctaetrieodninmaU.yS.noPtatbeentreOpfrfiocdeu;cedCoepityhreirghitn w1h9o6l8e boyr Micn Gpraarwt-Hwiiltlh,ouItnct.heAllcornigshetnstroefsecrovpeydr.igThhteocwonnetre.nts
Subscribers: The publisher, upon written request to our New York office from any subscriber, agrees to refund that part of the subscription price applying to copies not yet mailed. Please send change of address notices or complaints to Fulfillment Manager; subscription orders to Circulation Manager, Electronics at address below. Change of address notices should provide old as well as new address, including postal zip code number. If possible, attach address label from recent issue. Allow one month for change to become effective. Postmaster: Please send form 3579 to Fulfillment Manager, Electronics, P.O. Box 430, Hightstown, New Jersey 08520

4

Readers Comment
In search of protection
To the Editor: Iam afraid that Petar Volkov's
SCR regulator [Feb. 5, p. 88] will not always work properly; at least, it will not work with agood transformer. For instance, Iam working on an amplifier intended for 120 watts rms at audio frequencies, using an output transformer and two 2N3055 transistors. Ifound that it needed 42 volts d-c at full load, about 5 amperes. Icalculated the power transformer output as 45 volts rms; a5,000-microfarad input capacitor would do, and the transformer output impedance, seen from the secondary, is about 0.5 ohm. With no load, the power supply's output would be about 60 volts d-c. However, this is too high--an input signal would kill one transistor and then a 115-volt collector-to-emitter voltage would kill the other transistor. Therefore, regulation was needed and Volkov's design seemed a likely candidate.
But after making some calculations Ifound that if the voltage was just under the desired 42 volts at the output, the Km of Volkov's circuit would conduct before aphase angle of 40° was reached, and the input's peak voltage would charge the capacitor to 65 volts--back to the original undesired condition. Thus, ahuge time constant would be necessary, and the resistor would cause much undesired heat. So Iam looking for something else. Perhaps an ordinary transistor and a diode in lieu of the SCR of Volkov's design, or atwo-capacitor arrangement.
Allain Le Solleuz Brest, France
The author replies:
As Iunderstand it, you need a protection against voltage rise during no load periods.
A classical solution of this problem is not to use a C-input filter at all (as you and Idid, Iguess), but rather an L-input filter supplied with the Lecessary bleeder.
If weight and volume are to be kept to aminimum, then Isuggest you use the scR regulator in my
Electronics IApril 15, 1968

Add Sprague Series 7400A to your prints for Series 74N TTL circuits. They're pin-for-pin identical.

SERIES 74N
SN7400N SN7401N SN7402N SN7410N SN7420N SN7430N SN7440N SN7450N SN7451N SN7453N SN7454N SN7460N SN7470N SN7472N
SN7473N --
SN7474N --

FUNCTION
Quad 2-Input NAND Quad 2-Input NAND (No Collector Load) Quad 2-Input NOR Triple 3-Input NAND Dual 4-Input NAND Single 8-Input NAND Dual 4-Input NAND Buffer 2-Wide 2-Input Expandable AND-OR-INVERT 2-Wide 2-Input AND-OR-INVERT 4-Wide 2-Input Expandable AND-OR-INVERT 4-Wide 2-Input AND-OR-INVERT Dual 4-Input Expander D-C Clocked J-K Flip Flop J-K Master Slave Flip Flop Dual J-K Master Slave Flip Flop:
Single chip, pin 11 GND Single chip, pin 7 GND Dual D-Type Edge-Triggered Flip Flop Dual AC Clocked J-K Flip Flop

SPRAGUE PART NO.
USN-7400A USN-7401A USN-7402A USN-7410A USN-7420A USN-7430A USN-7440A USN-7450A USN-7451A USN-7453A USN-7454A USN-7460A USN-7470A USN-7472A
USN-7473A USN -74107A USN-7474A USN-7479A

Series 5400, full-temperature-range equivalents in 14 pin flat-packs, are also available for rapid delivery from Sprague.
Don't spend another

wegMe(k

without calling Sprague.

For complete technical data on Series .5400 and 7400A circuits, write to Technical Literature Service, Sprague
Electric Co., 35 Marshall St., North Adams, Mass. 01247
SPRAGUE WORCESTER...the world's finest microcircuit facility
Electronics jApril 15, 1968

SPRAGUE®
THE MARK OF RELIABILITY

Sprague and 'CD are registered tra4emarks of the Sprague Electric Co.

Circle 5on reader service card

5

Bolt anew METERMATE to any panel meter
... it's asingle-ended D.C. voltmeter ... it's ahigh impedance differential voltmeter ... it's alog scale D.C. voltmeter ... it's alog ratiometer D.C. voltmeter ... it's a"you-name-it-we've-got-it" meter Now standard panel meters read voltage at high source impedances. METERMATES for various functions mount flush at the rear of the meter and fit within the length of the meter terminals-- take no extra space, install easily. Ranges are altered simply by changing one external resistor value. METERMATES are available as individual units or with companion meters in acomplete selection of types and ranges. Call your Philbrick/Nexus sales representative for complete specifications, prices and applications assistance. Or write, Philbrick/Nexus Research, 22 Allied Drive at Route 128, Dedham, Massachusetts 02026.
ONIIL PHILBRICK/NEXUS RESEARCH
A TELEDYNE COMPANY

6

Circle 6 on reader service card

Electronics !April 15, 1968

F It

circuit, followed by a transistor d-c stabilizer. Here the scu regulator is used only to cut the power dissipation in the transistor d-c stabilizer (as much as 50%).
I must warn you that this sot regulator has aripple in the output; this is inherent in its trigger operating nature. But such acl-c voltage is good for loads like relays, signal lamps, electromagnetic valves and small d-c motors.
Petar Volkov Zagreb, Yugoslavia
Seen in adifferent light
To the Editor: The particular point we wish to
make pertains to the cover picture on your March 4th issue and your comments on page 81 as follows, "On the cover, six of these arrays are appropriately lighted to depict a running figure." A casual examination of the front cover reveals that the picture has been assembled from six photographs of the sanie matrix rather than from six matrixes.
This may appear to be a minor objection, but, examined more closely, it has deeper significance. There are only afew manufacturers with proven capabilities of fabricating light-emitting diode arrays and the relative capabilities of these companies are largely determined by their ability to improve emission efficiency and display area. The display device on your cover is onesixth of the area shown; it is x-y addressed and, therefore, multiple exposures were used to create the photographs--with multiple exposures the apparent brightness can

be artificially altered; not all segments are illuminated and, in fact, eight of the diodes are not illuminated in any of the pictures. Through the use of art work and scientific photography adeceptively attractive display has been assembled.
Bowmar Canada Ltd. in 1965 fabricated a7x9matrix of infrared diodes on asingle 0.2" x0.3" substrate and, the same year, amatrix of red-emitting gallium arsenidephosphide diodes of equal size. Subsequently we have developed monolithic arrays of gallium phosphide diodes with individual access which permit simultaneous exposure of each data point. The status of our display laboratory in the North American marketplace hinges on our ability to build advanced display devices.
While we realize that modern advertising will always present an exaggerated impression of the state of the art, we feel that your editorial comments should be carefully weighed to prevent presentations of the form described above.
Robert D. Rinehart Vice president, Operations Bow-mar Canada Ltd.
·As Robert Rinehart says, even the most casual examination of the cover shows that the sanie matrix was used six times. We did not expect our readers to draw the inference, from our description, that six different matrixes were used.
Readers' letters should be addressed: To the Editor, Electronics, 330 West 42nd Street, New York, N.Y. 10036

1 , SUBSCRIPTION SERVICE
IPlease include an Electronics Magazine address
label to insure prompt service whenever you Iwrite us about your subscription.
Mail to: Fulfillment Manager Electronics P.O. Box 430 Hightstown, NJ. 08520

ATTACH LABEL HERE

CHANGE OF ADDRESS
If you are moving, please let us know five weeks before changing your address. Place magazine address label here, print your new address below.

! To subscribe mail this form with your payment
I and check D new subscription D renew my
present subscription

name

I Subscription rates: qualified subscribers in the I U.S.' 1 year $8; two years, $12; three years,
$16. Non-qualified: 1 year $25. Subscription I rates for foreign countries available on request

address city

state

zip code

Electronics April 15, 1968

"Four to six weeks for power supply delivery?
Forget it!
Acopian will ship any of their 62,000 different AC to DC plug-in power supplies in just 3 days!"
This catalog lists 62,000 models of AC to DC plug-in power supplies available for shipment in just three days. Choose the exact outputs you need. Singles or duals, regulated or unregulated. Write or phone for your free copy.

Name

Tide

Company

City

State

Zip

Acopian Corp, Easton, Penna. 1804?
Phone: (215) 258-5441

Circle 7 on reader service card

7

=nape 29

The Year of the ém4 Marathons ... 6t4u,x4),1,04, eLketa,

1964, to most

everyone, is best

remembered as the

year in which

Bikela Abebe of

\

Ethiopia won the

Olympic marathon

in the record time

of 2h.12m.11.2s.

Without wishing to denigrate this achieve-

ment, it should be noted that 1964 was also

the year in which Motorola was party to a

space shot that set many marathon records.

The shot was Mariner 4, launched at Mars in

November, 1964. One of the records is for

long distance communications: signals were

received from more than two million miles out

in space. The second record is for distance

traveled. Mariner 4traveled more than 350-

million miles just getting to Mars; and kept

going strong, logging more than 1.5-billion

miles before finally being shut down by JPL in late December of 1967. While NASA/JPL

deserve most of the credit for these records,

we want the world to know that it was our

CW transponder and Flight Command subsys-

tem that made vital contributions to the com-

munications and guidance of the now ancient

Mariner, thereby making these records pos-

sible. Just about the time Mariner 4celebrated

its third anniversary, the boys at JPL com-

manded it to break lock on the guide star

which had been controlling its attitude

throughout most of its journey, and all sys-

tems, including ours were still in fine shape.

If these monumental achievements don't im-

press you, our Aerospace Center communica-

tions people would like you to write and tell

them what does.

KeePiÑG

51%MIIF !ME

you can simmer down. Our Guidance Systems R&D experts have breadboarded some highly advanced ideas for improving the guidance system of SAM, a small tactical missile its deployers would like to keep on target. The improvements are in the realm of doppler modulation techniques which help attain more rapid acquisition and improved range resolution. Some achievements are: an advanced phase monopulse antenna, multiple modulation techniques that operate with a single illuminating radar system mode, and improved microwave integrated circuits. If you have aSAM of your very own ... or aGus, aBen, or even aFarley, maybe we can help guide it. Send a missive to the Guidance Programs Office at our Aerospace Center.
Shapc Up, Infidels!
How many of you would know what
tdorodpopiefdwean ,
MR-300 on your doorstep? Would it help if we told you it is also called the AN/ FRC-147(V)? Probably not; so listen. The MR-300 is the world's greatest solid state microwave equipment. That's because it has silicon transistors for ultra-reliability, a 2-watt long-life klystron that assures afull 1-watt (+ 30 dbm) power output to the antenna, a600 channel capacity using SSB multiplex or equivalent loading, alow noise receiver featuring optional tunnel diode amplifier, and lots of other nice things. Write to the Microwave Program Office at our Chicago Center for astirring spec sheet. Who knows, we just might leave an MR -300 on your doorstep. So be prepared.

Does your small tactical missile wander aimlessly about the sky, seemingly more interested in sight-seeing than hitting whatever you aimed it at? Well, now

Aerospace Center Dept. 2008 8201 E. McDowell Rd., Scottsdale Arizona 85252, Phone (602) 947-8011
Chicago Center Dept. 985 1450 N. Cicero Ave., Chicago, Illinois 60651, Phone (312) 379-6700

MOTOROLA

Government Electronics Division

8 Circle 8on reader service card

People

The Electronic Systems division of

the TRW Systems Group is chang-

ing its ways, says Paul F. Glaser,

41, the divi-

sion's new as-

sistant general

manager for

projects. He

notes that where

the division--as

well as the en-

tire systems

group--has tra-

Glaser

ditionally been in the space busi-

ness, with its few-of-a-kind pro-

duction requirements, there is a

thrust now to get into more sus-

tained production. "One of the di-

vision's changes of pace has been

toward hardware production and

away from the image we have of

being an analysis and study

house." To back up this change,

the division is adding afacility in

Manhattan Beach, Calif., which

will have 500,000 feet of manufac-

turing space.

"We're developing a capability

for quick reaction--an ability to

turn designs into hardware with

a short turnaround time. An in-

creasingly larger amount of our

efforts are going into avionics sys-

tems, including electronic counter-

measures equipment. We're doing

this because we foresee such things

as v/sToL aircraft and the super-

sonic transport requiring com-

mand, control, and communications

systems as complex as those used

in some of the space systems we

provide."

New direction. Glaser concedes

that NASA'S fiscal plight has been

afactor in reorienting his division.

"We're now building spaceborne

programers and data processors,

but we've also made proposals on

this kind of equipment for aircraft

that could lead to reasonably high

production volumes." Glaser esti-

mates deliverable hardware now

represents about 20% of the divi-

sion's business; he expects that fig-

ure to double in five years.

He also predicts drastic changes

in electronic equipment design

over the ext decade because of

the influence of large-scale integra-

tion. Glaser says mw officials had

Electronics April 15, 1968

m

The ML-EE64Y is the smallest 10 kv (peak) switch tube--and the smallest 10 kv (peak) regulator tube you can buy.
ML-EE64Y gives you up to 36 free cubic inches per tube, and doesn't require asocket. It offers you a12 amp peak
current, high signal sensitivity, and asimple Be0 heat sink with no other cooling required. The ML-EE64Y provides tabs for simple, low-cost connection. For complete data, write to Machlett--the tube specialist
most responsive to customer needs--today. The Machlett Laboratories, Inc., 1063 Hope Street, Stamford, Connecticut 06907.

Why use this tube...for high voltage switching or voltage regulation...when this one is better?

ML-EE64Y Actual size.

THE MACHLETT LABORATORIES, INC.

A SUBSIDIARY OF

RAYTHEON

COMPANY

Electronics April 15, 1968

Circle 9 on reader service card

9

Breakthrough by Dearborn!

People

this in mind when they worked
out plans for the new home for 4,400 Electronic Systems division employees.
"We wanted to bring engineering and manufacturing very close
together," Glaser says, "because there's such a close tie between the chemist, physicist, designer, and manufacturer. It will be hard
to say where physics stops and manufacturing begins."

100 oF @50V
in 1" x33M 1metal-encased
METALLIZED POLYCARBONATE-FILM CAPACITORS
e Capacitance range of Dearborn DIMIE®
Series now extended to almost 18 times higher than previously-available values!
M A new order of size and stability in capacitors
for critical low-voltage miniaturized circuits.
oe Rated for operation at temperatures to
+125 C without derating.
ID Low loss characteristics, high current-carrying
capabilities--ideally suited for specialized a-c and r-f applications.
For complete technical information, write to Dearborn Electronics, Inc.,
Box 530, Orlando, Fla. 32802.

7101P1

Electronic la subsidiary of the Sprague Electric Company)Inc.

S ·,

FOREMOST IN FILM CAPACITORS

10

Circle 10 on reader service card

Walter B. LaBerge, who has just

stepped into the top post at the

Philco-Ford Corp.'s electronics

group, is con-

vinced defense

spending is

about to level off

--perhaps even

taper off. This

thrusts upon the

new Philco-Ford

vice president

the task of chan-

La Berge

neling his divisions' resources to

provide the nonmilitary area with

an increasing share.

"Fortunately," says the 44-year-

old LaBerge, "our six defense,

space, and industrial electronics

divisions have long experience in

communications and digital han-

dling, experience that is in grow-

ing demand in the civilian sector."

Emphasis. LaBerge, who has a

Ph.D. in physics from the Univer-

sity of Notre Dame, is quick to

point out that defense needs will

still run high. "We've learned two

lessons in Vietnam. First, we know

that we'll have to continue putting

our defense dollars into weapons

for that kind of war. Second, com-

mand and control problems--tac-

tical, strategic, and logistic--will

receive greater emphasis." This,

adds the Philco-Ford executive, is

right down the alley of two of his

divisions, WDL and Communica-

tions and Electronics.

The company is already apply-

ing the antenna technology used

to track satellites for the commun-

ications subsystem of the Bay

area (San Francisco-Oakland)

rapid transit system, and for work

related to California's water re-

sources.

Electronics IApril 15, 1968

In less time than it takes to read this page, you could learn to use
this new Universal Impedance Bridge.
Ready? One, two, three, go.

2Adjust the range switch for an on-scale reading.
1¡,9 46O tVERS..M,,. r*D.G:

6

tINKWOWN.

Late

Cs reel R.'

Le

mor`e Lora «qr.

1E119Rn/in.

,,t ·Obtain anull with the CRL dial. Now, read your
measurement.

1·Select the function you want.

Nothing to it. No interacting controls to adjust and readjust. No multipliers. No non-linear dials. AUTO-BALANCE eliminates all that.
This new Hewlett-Packard Bridge is the first
one that takes human beings into account as well as impedance. It's made for engineers who don't have time for ahalf-hour refresher course every time they want to use it.
You get direct digital readout of all C, R, and L values. Indicator lights show up-scale or
down-scale unbalance. Decimal point and an equivalent circuit are automatically indicated. No problem with false or sliding nulls either:
unique electronic AUTO-BALANCE takes
care of that.

For aD or Q measurement, just switch from AUTO to low or high D or Q and turn the DQ control until you obtain another null. Simple. Particularly for low Q and high D cases.
So if you're the kind of engineer who's tired of complicated impedance bridges, HewlettPackard has your number: Model 4260A, $550.
Ask your Hewlett-Packard field engineer for a demonstration. Or write us for complete specs: Palo Alto, California 94304. Tel. (415) 326-7000. Europe: 54 Route des Acacias,
Geneva.

HEWLETT â

PACKARD
An extra measure of quality.

Electronics April 15, 1968

Circle 11 on reader service card

11

TO YOU DESIGNERS DEDICATED TO BUILDING SIMPLER,
LOWER-COST
SILICON POWER CIRCUITS

Nowadays, complementary symmetry is the way to go when you're after more economy and less complexity in the power portions of your industrial circuit designs.
You get all the circuit-simplifying advantages of direct-coupled, complementary symmetry plus realize ahigher degree of frequency stability in both ac and dc-driven loads without the addition of expensive, impedance-matching driver transformers.
And Motorola has the broadest 3-to-30-ampere, NPN/PNP silicon power transistor line available anywhere for the widest range of cost-cutting, directcoupled application possibilities in the industry -- 27 silicon power pairs ...headed by the unique 30 A, 200 W units ...in your choice of voltage, gain and power capability.

,T .TTTESITOGIRE T CEMPUITUE
(AN225, AN230)

Complement your new design prototypes with one of Motorola's 3-to-30ampere silicon power pair kits ... available for alimited time for 30% below list price! We'll include two informative industrial application notes: "High-Performance All Solid-State Servo Amplifiers," and "Complementary Solid-State Audio Amplifiers" that discuss at length phase shift reduction and easy conversion to trans-
formerless operation. Just fill in and mail the coupon to receive this outstanding "3-to-30 offer".
Pair up with silicon power!

anal 0, wovnted onhe.d rinks., caw E. arl.1,.,m vo.T..lroivanceil8 C

Teach to., TsloO

COMPLEMENTARY SILICON POWER SERVO AMPLIFIER
Both ac and dc-driven loads can be utilized with this simple, compact amplifier which will drive 20 V (RMS) in a40n load, giving an output of 10 W. Voltage gain at 25°C is 37 dB and gain variation over --55°
to +100°C operating range is within ±5 dB. Power gain is 60 dB (min). Harmonic distortion is less than 5% at all levels up to 20 V (RMS) and is typically less than 1% at 25°C.

A, REQUIRED ID GIVE 211 40 1.1, E. ADES OUIESCENT CURRENT IN 0, AND 0, All, RESISTORS 1/2,,ATT. 15, UNLESS OTHERWISE INDICATED.
COMPLEMENTARY SILICON POWER 50 W AUDIO AMPLIFIER Excellent frequency response -- 5cycles to 300 kHz -- is obtainable with this industrially-oriented amplifier. It can provide 65 W at 20 Hz, 72 W at 1 kHz and 68 W at 20 kHz. Flat frequency response results from 100 Hz to 20 kHz, being down only 0.35 dB at 20 Hz. Phase shift is 18° at 20 Hz and 6* at 20 kHz.

-witee tit pyueeeem ih9/zediett te eade!

12

Electronics April 15, 1968

...OUR COMPLEMENTS.

IC Max. Amps
3
4
5 10 15 30

%ICE° Volts (sus)
40 60 80
40 40 60 60 80 40 60 80
40 60 80 40 40 60 60 80 80 60 60 80 80 60 40 60

Package Case 77
TO -5 Case 77
TO-66
TO-3
TO-3 TO-3 TO-3

MOTOROLA 3-T0-30 A COMPLEMENTARY SILICON POWER

Type

NPN

PNP

2N4921 2N4922 2N4923

2N4918 2N49 I9 2N4920

2N3506 2N4237 2N3507 2N4238 2N4239 2N5190 2N5191 2N5I92

2N3867 2N4234 2N3868 2N4235 2N4236 2N5193 2N5I94 2N5195

2N4910 2N4911 2N4912 2N49 I3 2N5067 2N4914 2N5068 2N4915 2N5069 2N3713 2N3715 2N3714 2N37 I6 2N3055 2N5301 2N5302

2N4898 2N4899 2N4900 2N4904 2N4901 2N4905 2N4902 2N4906 2N4903 2N3789 2N3791 2N3790 2N3792 2N4908 2N4398 2N4399

hFE e lc 20/100 @ 500 mA 40/200 @ 1.5 A
e 30/150 @ 0.25 A
40/200 1.5 A 30/150 @ 0.25 A 30/150 @ 0.25 A 25/100 @ 1.5 A

20/100 @ 0.5 A

25/100 @ 2.5 A

ee 20/80 @ 1A

25/100 2.5 A

20/80

1 A

25/100 @ 2.5 A

20/80 @ 1A

25/90 e 1A 50/150 e 1A 25/90 @ 1A 50/150 e IA

20/70 @ 4 A

e 15/60

15 A

PD Watts
30
6 30 25 87.5
150 115 200

VCE hall 0 lc Volts (max) 0.6 @ 1A

ee 0.75 e 1.5 A

0.6

I A

0.75 1.5 A

0.6 @ 1A

0.6 @ 1A

0.6 @ 1.5 A

0.6 e 1A
1.0 @ 2.5 A 0.4 @ 1A 1.0 e 2.5 A 0.4 e 1A 1.0 e 2.5 A 0.4 @ 1A 1.0 @ 4 A 1.0 @ 5A 1.0 @ 4 A 1.0 @ 5A 1.1 @ 4 A
1.0 @ 15 A

fr MHz
3 3 3 60 3 GO 3 3 4 3 3 3
4
4 4 4 4 1 4

NPN /PNP Rego rar Combination
Price (1-99) $ 2.98 3.38 4.05
26.50 5.25
29.95 6.35 7.05 3.58 4.00 5.95
3.50 4.40 5.00 5.75 4.55 7.05 5.55 9.80 7.10 13.30 17.20 15.35 21.60 11.15 18.10 21.10

"3-30" PAIR-UP-WITH-SILICON-POWER OFFER

The silicon power pairs below are offered at 30% below regular, combination, NPN/PNP, 1-99 list prices. Pair me up with a:

_ 3 A, 80 V 2N4923/4920 Kit ...Special "3-30" kit price $ 2.75
__ 3 A, 80 V 2N4239/4236 Kit ...Special "3-30" kit price $ 4.95 _ 4 A, 80 V 2N5192/5195 Kit ...Special "3-30" kit price $ 4.15
__ 4 A, 80 V 2N4912/4900 Kit ...Special "3-30" kit price $ 3.50
- 5 A, 80 V 2N5069/4903 Kit ...Special "3-30" kit price $ 4.95 _10 A, 80 V 2N3714/3790 Kit ...Special "3-30" kit price $10.75 __30 A, 40 V 2N5301/4398 Kit ...Special "3-30" kit price $12.65

All kits include AN225 on Servo Amplifiers and AN230 on Audio Amplifiers.

Send me data sheets on the

A,

V devices.

TO-66

Name

Title

Company

Div/Dept.

Address

City _

State

Zip

(Be sure to include check for appropriate kit ordered payable to Motorola Inc. Mail to Motorola Semiconductors, Box 955, Phoenix, Arizona, 85001. Offer void after June 1, 1968.)
"3-30" PAIR-UP-WITH-SILICON-POWER OFFER

TO -5

MOTOROLA semiconductors

Electronics lApril 15, 1968

13

Application For
FET SWITCHES
FRIO IIIMP UM IRMA SIM IMO BIM 11111 uI
PROBLEM: Use one flat pack to switch
two ± 10 V signals ...and drive with 5 V logic.
el OUT
ons -

Meetings

Southwestern Conference and Exhibition, IEEE; Sheraton Lincoln Hotel, Houston, April 17-19.

Human Factors in Electronics Symposium, IEEE; Mariott Twin Bridges Motor Hotel, Washington, May 6-7.

Symposium on Automation Techniques in Industry, Institution of Electronics and Radio Engineers; Paisley, Scotland, April 17-19.
State of the Art Seminar: Components and Devices in System Applications, Purdue University; Lafayette, Ind., April 19-May 25.
Conference on Switching Techniques, IEEE and Institution of Electrical Engineers, Institution of Electronic and Radio Engineers; London, April 21-25.

National Conference on Aerospace Meteorology, American Institute of Aeronautics and Astronautics; New Orleans, May 6-9.
Technical Conference and Exhibit, American Society for Quality Control; Sheraton Hotel, Philadelphia, May 6-8.
Electronic Components Technical Conference, IEEE; Everglades Hotel, Marriott Twin Bridges Motor Hotel, Washington, May 8-10.*

REQUIRED: Two switching channels completely contained in one package ... Delay less than 1µS ...Inverting logic (logic low - switch OFF) ... -55°C to +125°C operation.
GIVEN 1. ei r,±10 V. 2. DTL logic - output swing is 5 V. 3. Available power supplies: +5 V, +10 V. -20 V.

Conference for Protective Relay Engineers, Texas A&M, University; College Station, Texas, April 22-24.
Chemical and Petroleum Instrumentation Symposium, Instrument Society of America; Hotel du Pont, Wilmington, Del., April 22-23.
Frequency Control Symposium, U.S. Army Electronics Command; Shelburne Hotel, Atlantic City, N.J., April 22-24.

Short Courses
Data communications for management control, the American University, Washington, May 20-23; $175.
Computer-aided testing and failure diagnostics of solid state systems, University of Wisconsin, Madison, May 23-24; $50.
Digital control fundamentals, Milwaukee School of Engineering, Milwaukee, June 3-7; $150.

SOLUTION: Siliconix DGI 11F -Both
channels complete in one package, MOS FET switch and bipolar driver ...no other parts needed. Connect DTL output to driver input, ground "R", Vcc to +10, P and VEE to -20, apply ei n to source and drain is output.
z Tight packaging your hang up? ConW tact us for applications assistance or
; write for our free FET Switch and Driver Data Packet.

Siliconix incorporated L1140 W Evelyn Ave · Sunnyvale, CA 94086
one (408)245-1000 · 7WX. 910-339-9216

14

Circle 14 on reader service card

Region Ill Meeting, IEEE; Fontainebleau Motor Hotel, New Orleans, April 22-24.
American Power Conference, IEEE and Illinois Institute of Technology; Sherman House, Chicago, April 23-25.
Fiber Optics History Technology and Applications, Society of Photo Optical Instrumentation Engineers; Holiday Inn, Baltimore, Md., April 29-30.
Relay Conference, National Association of Relay Manufacturers and School of Electrical Engineering, Oklahoma State University; Stillwater, Okla., April 23-24.
Cybernetics Conference, IEEE; Munich, West Germany, April 23-26.
Spring Joint Computer Conference, American Federation of Information Processing Societies; Atlantic City, N.J., April 30-May 2.
Symposium and Equipment Show, American Vacuum Society; Grand Hotel, Anaheim, Calif., May 1-3.

Call for papers
Conference on Tube Techniques, IEEE; United Engineering Center Auditorium, New York, Sept. 17-19. May 15 is deadline for submission of abstracts to George Freedman, The Raytheon Co., Microwave Power Tube Division, Willow St., Waltham, Mass. 02154
Ultrasonics Symposium, IEEE; StatlerHilton Hotel, New York, Step. 25-27. July 15 is deadline for submission of abstracts to R.W. Damon, Sperry Rand Research Center, 100 North Rd., Sudbury, Mass. 01776
Allerton Conference on Circuit and System Theory, IEEE; Allerton House, Monticello, Ill., Oct. 2-4. Aug. 1 is deadline for submission of abstracts to T.N. Trick, Department of Electrical Engineering, University of Illinois, Urbana, Ill. 61801
Circuit Theory Symposium, IEEE; Hilton Plaza Hotel, Miami Beach, Fla., Dec. 4-6. Aug. 1 is deadline for submission of papers to B. K. Kinariwala, Department of Electrical Engineering, University of Hawaii, Honolulu, Hawaii 96822.
* Meeting preview on page 16.

Electronics April 15, 1968

Is there an AC digital voltmeter anyw ere that can measur -this
waveform accur tely?

And this one too?

%

Th ere is now! The new Fluke 9500A true rms automatic digital voltmeter reads these
complex waveforms to an accuracy of ±-0.05%. And if you know your AC's, that's progress.

Another DVM on the market? Usually that's good for aho-hum. But as we've said above, if you know your ac's, that's not the case with the new Fluke 9500A. It's the first automatic ac voltmeter capable of reading and digitally presenting the true rms value of any input--regardless of waveform--to 0.05% absolute accuracy (50 Hz to 10 KHz).
Frequency response is broad, 20 Hz to 700 KHz. The Model 9500A accepts voltage from .001 to 1100 volts rms in five ranges, each with 20% overranging. Range selection is automatic or manual.
Crest factor of 10 virtually eliminates effects from voltage spikes or pulse trains.

Low capacitance, high resistance input minimizes loading effects.
Self-calibration is automatic whenever the instrument is turned on. On-line self-
calibration is either automatic or manual, selectable by front panel switching. All controls and indicators, conveniently located on the front panel, are easy to use and understand. Complete control of the 950CA is possible from aremote facility if desired.
Price of the Model 9500A, including rack adapter, is $2,485. Extra cost options include aprobe input ($75), rear panel BNC input ($50), and 1-2-4-8 or 1-2-2-4 BCD digital outputs ($195). For

complete information, please call your full service Fluke sales engineer (see EEM), or `'rite directly to us here at the factory. Fluke. Box 7428, Seattle, Washington 98133. Phone: (206 )774-2211. TWX: 910-4492856. In Europe, address Fluke International Corp., P.O. Box 5053, Ledeboerstraat 27, Tilburg, Holland. Telex: 844-502.37. In the U.K., address Fluke International Corp., P.O. Box 102, Watford Herts, England.
FLUKE:
Circle 15 on reader service card

ALPHANUMERIC, DIGITAL AND
SPECIAL READOUTS

Sixteen segments; full

AIAP

alphanumeric presenta-

tion; 65,000 character

combinations.

Seven segments; 10 digits, 11 alphabetic characters, plus deci-
mal point/degree sign.

Special characters produced to order.

ALL WITH OPTIMUM CONTRAST AND ALL FROM TUNG-SOL

Optimum contrast in Tung-Sol readouts results from the molecularly bonded, flush-surface filter. The use of anew 20 mil lamp sharply reduces the load factor while maintaining good brilliance. Heat is minimized and reliability is substantially improved. Tung-Sol
readouts are designed to be inter-mixed. All characters have the same vertical dimension for accurate in-line display. Viewing angle is 150°. Displays can be supplied in color.

POT,JOL.L

MOUNTING FLEXIBILITY
FAOTENING

RECEOSED

PROTUDINO

EARS

BRACKETS

CLAMPS

Write for fully explanatory brochure T-431. Tung-Sol Division, Wagner Electric Corporation, One Summer
Avenu,, Newark, New Jersey 07104.

TUNG-SOL®

OPTIMUM CONTRAST

READOUTS

(T'r

T.M. WARNER ELECTRIC CORPORATION

16

Circle 16 on reader service card

Meeting preview
New spirit
The Electronic Components Conference, threatened with extinction afew years ago by the onrush of complex monolithic integrated circuit technology, is again back in the thick of things, with thick films. Along with the regular sessions on materials, packaging, and manufacturing, this year's conference, scheduled for Washington, May 8to 10, will, for the first time, llave two thick-film sessions.
Better performance. Among the speakers in this area will be Brian Dale, chief engineer at Sylvania's Semiconductor division, whose paper will cover the use of thick-film packaging techniques for fitting beam-lead devices to both hybrid microcircuits and inexpensive carriers. This is aprocess that eliminates double packaging, and makes possible air-isolated circuit components, resulting in improved high-frequency performance.
Other topics to be covered in the thick-film sessions are cermet resistors, screen-printed capacitors and high Q dielectrics.
Also scheduled is a session on integrated components and filters. In this session three Boeing engineers, V.C. Hughes, O.R. Mulkey, and M.H. Williamson, will describe how athin-film hybrid technique was used to fabricate 17 different audio frequency RC filters with tolerances of 0.1%.
Filter design. In the same session, J.M. Giannotto, a researcher with the U.S. Army Electronics Command, will discuss the use of energy-trapping techniques in acoustical filter design. He will cover the deposition of both thin films of cadmium sulfide and resonators on quartz wafers, a process that obtains the electrical performance of conventional filters while cutting size.
Two Westinghouse engineers, M.B. Shamash and S.G. Konsowski, will describe their work in packaging in a paper on the use of nonporous thin-film dielectrics and shadow printing of high-resolution conductors.
For further information contact William S. Hepner Jr., Electronic Industries Association, 2001 Eye Street NW, Washington, D.C. 20006
Electronics IApril 15, 1968

We make planar power.

Not excuses.

hFE 25 min. (0 2A, 10V 80 min. 0 3A, 10V 20 min. (0 5A, 10V
15 min. (a 10A, 5V 20 min. (0 10A, 5V

VC E0 40V
40 to 80V

(mIaCx .) VCE (sat)

3A

0.5V max. (0, 1A, 0.1A

5A

0.75V max. (0 3A, 0.3A

10A

1V max. 01., 5A. 0.5A

60 to 100V

15A 20A

1.5y max. fm 15A, 3A
1.5V max. ri 20A, 4A

PT
25W to
50W
100W 60vy
100W 60W

SWITCHING TIME

ton toff o lc o la

ns ns

A

mA

35

75

1.5

150

40 .00 3.0 300

225 600 10

1,003

TYPE
2N4225 B-143002 5, 8 B.14301 -7. 20, 23 13-144002, 5, 8 B-145002, 5, 8 8-146002 5, 8 13-148002 3, 5 B-155002, 3, 5 13-14800). 1, 4 13-155003. 1, 4

(SATURATED SWITCHING TEST CIRCUIT DIAGRAM FOR B-148000 & B-155000)

113
+VIN 2IWII
45890RFC 250

eioN 7 5a 1000 OF
T
55F Is r
TI TEKTRONIX PART* Or, 04 (5nWirnA I

Maximum Switching Times: tc < 25 ns ;

tr < 200 ns; ts < 300 ns; tf < 300 ns.

Test Conditions: Vin

70V when generator

with 5O2 inter -toi impedance is termincted in a

501.2 load. VBE -- 5V; VCC 55V; IC 10A;

ee 1A; 11321----1A; tp 400 ns; f--720 Hz.

Ever been handed the lin?: "Seems we have every type but the on you want--could we interest you in something else?" Excuses, excuses. It's nice to know Bendix doesn't need to make them. Fact is, you never have to compromise when 3electing our silicon planar power transistors. We mace over 100 different types, in 8 different packages, with collector currens of 3, 5, 10 and 20 amps, rated \; CEO 's from 40 to 100 volts. Contact us for postradiation gain data.
All Bendix planar power transistors are SOAR (Safe Operating ARea) specified to prevent second

breakdowns. A real time-saver in designing your power ampl:fier, inverter, converter and regulator circuits.
If you are in the market for radiation-nsistant transistors, silicon power mesas, DC voltage regulators or 35- and 60-volt plastic power traisistors, odds are we can meet your requirements there, as well. Excuses? Not from Bendix. We're the Power Specialists. More information? Call our nearest sales
woo office, or write: Semiconductor Division, The Bendix
Corporation, Holmdel, New Jersey 07733.
Bendix Electronics

Chicago--(312) 637-6929; Dallas--(214) 357-1972; Detroit--(313) 548.2120;

part, N.Y.--Harry Friedman Co. (516) 692-2839; Great

Neck, N.Y.--H. V. Sales Co. (516 , HU 7-1142; Greenwich, Conn.--(203) 8'59-7/9 Holmdel, N.J.--(201) 946-9400; Lexington. M.SS. --(617)

861-8350; Los Angeles--(213) 776-4100; Minneapolis--(612) 926-4633; Orlando, Fia. --(3)4) 241-6559; Rochester, N.Y.--(716) 266-5550; Run-

nemede, N.J.--(609) 933-2550; Se attle--Ray Johnston Co.. Inc. (206) LA 4-5170; Export--Cable: "Bendixint," 605 Third Avenue, New cork, (212)

973-2121; Ottawa, Ont. --Computing Devices of Canada, P.O Box 508 (613) 829-1800: San Juan, Puerto Rico--Soathern Internationa Sales Co.

723- 0379.

Electronics April 15, 1968

Circle 17 on reader service card

17

It itttIttitIttti tottIslitiftle, IttlfstIttlt1 iteftiollelf# 1,4édItiftti ss 01 ,1Ittelf11. fittitit,« 411 ' li#41t4iff# 444 ' Of#4$ttlititt4 tflifftttu all', ittellit 44111$ tsittiftlit 4tt, MS1411111 414* iGmifoftItlllIfS,*f1i1d1é1f1' tfirfiffltil lt, 6.11011111" 11. ,Itilleff$ 1101. fèfilittlit 41. 111184114f 11 *# ., ftIttliettItf .
ittlIt444 1 $11#
W111441614 ,1
W11411140111 , >fiffél$111 1 .11. fit4141411 1111 è tf#ItIff,01 14, ' 14.14*.4#91#1 4
tstiffIrefffiG . elottaliéttiit t tOitfiftfl.tel , tottittfititt 4 44411401MM , fitMtf4111114 #1414f$4140fC tt.ittitttift . DitifitIlltlit it,t14114t 1 tet
tf.i$41 11,44 4, t 1444o4000$ditil f$01Iffittlito 1644M1011110.1 tttlftfit4441 4
effilfillf4141 fit,11411.1$0 0
ètfIlltéllifff /ifftliffIffilU Ifillf416114It IffiffIffistlf tifetIfflit44.
414iffeltstot 11111Ittimittl )14$411foétéis ititteltstiff.
if itifilltéitti )HM6011.11. ititliffillf It ;itif filif
1111.44 410 $1 flef f fi fit MOM if dd tt401011#041f.
M. NWIA1.4101411. 141104111~
$4.111114111f II t ·1 4*h$5àiás

II
e e e e

on the standard 1p-sec I/C memory system that packs 1/2 million bits in asingle 51/4" high unit.

That's the ICM-40. A fast, highly reliable core memory system that's ready to meet your system requirement.
And when you say so, we'll give you 3-week CFS (Certified Fast Shipment) under our accelerated shipment plan.
What's more, the ICM-40 is astandard product... aproven performer with over 5,000 hours of life test without failure. Plus, some 400 actual installations; same success rate. What you'd expect from the most experienced memory maker.
I/C Construction -- The ICM-40 is a1microsecond, full-cycle, magnetic core memory designed for operation as ahigh-speed random-access store. It is abasic system module that takes maximum advantage of the high reliability and row power consumption of integrated circuitry.

Packaging -- Compactness and ahigh degree of maintainability are achieved in the ICM-40 design by packaging all of the circuitry on readily accessible, removable circuit modules.
Capacity -- The ICM-40 packs nearly 1/2 million bits in asingle 51/4"high module. The basic unit can be specified for up to 16K words, 4-26 bits per word. It's big brother, the ICM-40E with capacities of 32K words, 4-78 bits per word is available with 60-day CFS.
If you've drawn ablock marked "core memory" recently, why not find out more aboLt the ICM-40140E. You'll be pleased by their versatility. And the standard-product pricing. And our Certified Fast Shipment commitment.
Now, don't you think it's about time you called us? Or, write Honeywell, Computer Cortrol Division, Old Connecticut Path, Framingham, Massachusetts 01701.

Honeywell

43c COMPUTER DIVISION

CONTROL

Circle 19 on reader service card

4500 BIPOLAR MICROMAIRIX ARRAY

9- _ 7r.--_,f,.r,

.., ,

il± (1>1)

1-- 4'

PP ."P 12;

f
1- ""

"" -1

-Pr

5-Li-!-----I4. .7557_,5-;------iti5

41 _In, .;-:r1 1-1P,

,-,r. 1----ft,27?1---4 5 1------1 ri'5 }-------I

_ _, +¡1 -L,3-

17 1r.1 Lb

__,

7-.3"

_ _ Lfr"

p

"-

CIRCLE READER SERVICE NUMBER 121

3705 8-CHANNEL MUS MULTIPLEX SWITCH

1 1 1 1 I I1

_Irri7rLITrr-1717r:n-7r"rri 7r1

r i ri r1 ri

r1 ri r1

20

CIRCLE READER SERVICE NUMBER 123

RECAP:
3320 MN MAIL 4-PHASE SHIFT REGISTER

CIRCLE REAL ER FRVICE r.
0722 PROGRAMMABLE DIA-AID CONVERTER CURRENT SOURCE

? ? ? ? ? ? ? ? ? ? rFrrrn-rfrrrrrtrrrurr

a [LP [Err'

[31 1i

rfiri144 1

CIRCLE READER SERVICE NUMBER 1:4
Electronics April 15, 1968

Fairchild is introducing a new integrated circuit every week. The last two months look like this.
Uctiaidakii
SEMICONDUCTOR
4510 DUAL FOUNT COMPARATOR

EOM

IV't E REA

R CERVICE NuMBER 1. 5

27. 3750 10-BIT MOS-ESI DIA CONVERTER

F rr-r-r-r-r-r-r-n-[-r

9034 2511-BIT READ-ONLY MEMORY
r---

r--r r---r--
r--
r--

irr rer r
ri )

28. 902419625 INTERFACE CIRCUITS

SNE LL RLACER SERVICE NUMBER
Electronics IApril 15, 1968

CIRCLE READER SERVICE NUMBER 128

21

Which IC Test System
does all these things?

DIAGNOSTIC COMPUTER PROGRAMS automatically check out system operation.

DATALOG A FORCING FUNCTION, such as the input threshold level of aflip-flop needed to
produce aspecified output.

AUTOMATIC SELF-CHECKING assures accurate data transfer ' between operator, teletypewriter,
computer and test instrument.

TYPED SUMMARY SHEETS. Whenever desired. No interruption in testing. Give total units tested per test station, test yields and bin yields.

VERY COMPLEX TEST
SEQUENCES can be programmed, yet preparation of simple
tests can be learned in two hours.

FAST TESTING. 1.5 msec per test.
If crosspoint is changed, 5msec. 10 msec on the lowest current scales.

GROWING LIBRARY of improved software packages to insure against obsolescence.

TEN-YEAR GUARANTEE for all instrument plug-in circuitry (it's almost all plug-in).
NO ADJUSTMENT OR CALIBRATION POINTS. (Eternal vigilance is the price you pay for asingle adjustment.)

DIRECT ENGLISH data logging type-out, showing job name, serial
number, test number, decimal point and units. -------

OPEN AND SHORTED CONNECTIONS and OSCILLATIONS are automatically detected. System stops when a selected consecutive number of these occur.

ABSOLUTE SOURCE CONTROL. Sources can be turned ON or OFF and changed in value in any sequence with variable delays from 100 µsec. to
as long as you please.

COMPLETE FRONT PANEL DISPLAY
at any desired step, simultaneously indicating all crosspoint connections, forced values, measured limits, binning decisions--everything
about each test.

DATALOG at any test station --without slowing down classification tests at any other station.
-MULTIPLEXING. Several jobs simultaneously. Any assigned, at any time, to any test station.

MINIMIZED REPETITIVE INSTRUCTIONS for the operator through data libraries, variable word length programming, and autopinning.

This one.

PROGRAMMABLE CURRENT LIMITS for each source at each test.

(complete for only $65,000)

This is our J259 computer-operated Automatic Circuit Test System. It includes ageneral-purpose digital computer, teletypewriter, test instrument (comprising modular elements: 24 x8crosspoint matrix, four volt-

age sources, measurement system,
and test deck), complete software package, and courses in IC testing,
system operation, and maintenance. TERADYNE, 183 Essex St., Boston, Mass. 02111 Phone (617) 426-6560.

22

Circle 22 on reader service card

Electronics ;April 15, 1968

Electronics April 15, 1968

Editorial comment
A little knowledge
Shock waves from the report issued by the Logistics Management Institute earlier this year have spread beyond the Defense Department, where it was commissioned, to touch the entire industry. The institute asserted that profits for defense contractors based on percentage of total capital investment are significantly lower than those of contractors not involved with the Government. And furthermore, the report said, even those lower profits are declining. The Lmi report suggested that the Government be urged to back off on controls for high-risk projects.
The Defense Department asked the Electronic Industries Association for its comments on the study; during EIA meetings in Washington last month, the report was alternately praised and pummeled.
Astudy that yielded contrary results was made by M.L. Weidenbaum, an economics professor at Washington University. It concludes that the large defense companies (North American Rockwell, Lockheed, General Dynamics, NIcDonnell Douglas, Grumman, and Thiokol Chemical) earn higher profits than nondefense firms of similar size. Weidenbaum's data shows that defense profits have grown steadily higher than nondefense profits over the past decade.
These conflicting conclusions could be attributed, in part, to the measurement techniques. Weidenbaum used net profits after taxes as apercent of stockholders' investment (return on net worth). But defenders of the Lmi report suggest that it is unfair to compare all the companies involved in the LNII study with the giant aerospace firms.
Congressman Chet Holifield (D., Calif.), commenting on the LNII study, emphasizes that the figures were obtained from many individual company profit figures-- some of them considerably higher than the average reported.
Providing still another viewpoint, Robert Higdon, a vice president of the Chase Manhattan Bank, notes: "Classically, profit opportunities attract competition which drives down prices. Defense contractors interviewed by Lmt stated that the primary reason for defense profit being lower than commercial profits was the severity of competition." Higdon thinks this is not necessarily bad, noting that under free-enterprise concepts, marginal companies will (Imp out, leaving the field to the more competent.
Many companies would like a more detailed breakdown of the I.M1 report--into companies and categories-- to help them see where they fit into the picture. Others are content with the ambiguities of the report. In this group was one company that believes the study has generated a "credible image" which might generate some Government action that would reduce the controls on high-risk projects.
Other dissenters to further analysis of the LNII report

were saying, off the record, at the Washington parley that it might cast doubt on LMI'S conclusions. We disagree. Additional analysis would benefit the entire industry. The Logistics Management Institute has conducted anumber of studies for the Defense Department and its recommendations have been factored into the procurement regulations. We think this respected study group would be the first to agree that more light should be shed on its report.
After Vietnam
Hanoi's response to President Johnson's enunciation of ashift in U.S. policy encourages the hope that direct discussions can be arranged between representatives of North Vietnam and the United States. It may be months or years before the war is ended but now, at least, we've caught aglimmer of light at the end of the tunnel.
The current peace maneuvers bring the question of "After Vietnam, what?" into sharp focus. A year ago, a committee of the Electronic Industries Association tackled it. Its report", issued last month, postulated a "most probable course of events."
The EIA study group believed that the U.S. would "continue its present policy of escalation, with the aim of achieving a political settlement or ultimately forcing a military settlement to the conflict." The study group sought to describe the market environment at the war's end for companies now in the defense/space business and to measure the impact on systems procurement and research and development. Its conclusions:
·After the war, defense expenditures will return to a level which would have been reached had there been no conflict. NAsA spending will decline throughout the war.
·Programs will be deferred if they aren't related to Vietnam and for some this may mean their demise.
·Electronics expenditures will undergo no significant decline despite individual program losses in the short term. The latter will be offset by other programs and by an increasing electronics content in all programs, so that the long-terni prospects for electronics are good.
Of the many programs that will be deferred while the war continues, research and development projects are most vulnerable. Before leaving his post as Secretary of Defense, Robert McNamara told Congress that special efforts were being made to cull out marginal R&D programs and to defer to "future years" all projects whose postponement would not have aseriously adverse effect on the future military capabilities of the U.S.
Congressman Joseph Karth (D., Minn.) put it aptly when he warned against the U.S. slipping into a "let technology wait" mood, while the war is being fought.
Programs that are deferred lose momentum and key personnel. An infusion of funds may often not be enough to revive moribund programs. Karth calls for acontinuing investment in R&D in the U.S. to provide acontinuing payoff, not only for asound defense posture but to find acure for our social ills. The point is well taken. In war or peace we cannot bypass technology.
The Post -Vietnam Defense and Space Market Environment

Electronics April 15, 1968

23

CAN OPENERS ADDING MACHINES
AIR CONDITIONERS AUTOMATIC TYPEWRITERS

PHOTOCOPIERS
· WASHING MACHINES

·

Q

·

VENDING MACHINES COMPUTERS

FILM PROJECTORS

CLOTHES DRYERS

want to start something?

COLLATORS

AUTO TURN SIGNALS

VACUUM CLEANERS RADIOS

1L==

TAPE RECORDERS

BLENDERS

PRINTING PRESSES

COFFEEMAKERS

PHONOGRAPHS

TELEVISION SETS

specify Cherry long-life switches

This year, 17 million products will start with Cherry switches. rig-o 1

Product designers like Cherry's long-life coil-spring mechanism. illinel

Production people find high-overtravel Cherry switches install SWIM

much easier. If you are looking to start something and need SIR operating forces as low as 114 grams or electrical ratings as high

as 25 amps, check CHERRY.

'FAEMI

Check our complete line. Send for the new pocket-size Cherry "Switch Selector Guide."

CHERRY
CHERRY ELECTRICAL PRODUCTS CORP. · 1656 Old Deerfield Road · Highland Park, Illinois 60035

TESTING EQUIPMENT

GARAGE DOOR OPENERS

POWER TOOLS
CALCULATORS Circle 24 on reader service card

DISHWASHERS DEHUMIDIFIERS

Electronics Newsletter

Siliconix to offer microwave FET's

April 15, 1968
Field effect transistors are not only bucking the trend to integrated circuits but are widening their scope of operation. The latest advance lifts commercial FET's into the ultrahigh- and microwave-frequency ranges. Siliconix has developed ajunction device with amaximum frequency of 1.5 gigahertz, plus again of 6,500 micromhos and anoise level of under 4decibels.
This frequency capability, triple that of rival off-the-shelf units, is achieved by 'twisting the basic geometric pattern," according to J. B. Compton, designer of the device. He expects the method to yield 3-Ghz devices by next year and says the technique is applicable all the way up to 10 Ghz.
Siliconix is aiming its new unit at communications applications, including radio, telemetry, and low-noise amplifying systems, but will also sell the chip in unpackaged form to hybrid-circuit users. The price will be under $6 each in lots of 100.

IC diode arrays get lift from air isolation

Fairchild Semiconductor is using a planar air-isolation technique to produce mon3lithic diode arrays that perform at the level of discrete arrays. The firm, which next month will introduce 16-diode and dual
eight-diode arrays incorporating thE new approach, says the isolation of the integrated-circuit elements is superior to anything achieved with dielectric, hybrid chip-and-wire, or other approaches.
The isolation--involving afine glass that is sedimented onto the front of the wafer and an additional support wafer--is laid down after the device elements are formed. It provides glass-encapsulation protection as well as normal oxide protection. As aresult, an epitaxial layer is left between top metallization and the p and n regions, with succeeding layers of oxide, aluminum, and glass interposed between bottom layers and the backing wafer.
Hal Clausen, senior marketing engineer for Fairchild, says the technique is applicable to all monolithic IC's, yields higher reliability, accommodates batch processing, requires fewer assembly operations, provides greater pin and layout freedom, and produces more uniform electrical characteristics. He further declares that the method will make discrete diode arrays obsolete.

TTL bandwagon

As transistor-=ransistor logic (TTL) finds its way into more integrated circuits, the race to get more of the action heats up. Motorola Inc., which announced its own TTL circuits late last year plus expansion of its secondsourced Sylvania SUHL 2 line [Electronics, Oct. 2, 1967, p. 179], is preparing a1"11 entry styled after Texas Instruments' 5400/7400 series.
The Semiconductor Products divisicn in Phoenix is making circuits now, but it will be -afew months," says one Motorola official, before they are available.
Meanwhile, in nearby Scottsdale, little Dickson Electronics intends to "have afling" at making TI's 7400 series, as its president, Donald Dickson, puts it. He says that if his firm gets good enough yields, shipments could begin late this year in the company's first venture into the monolithic IC arena.

Electronics IApril 15, 1968

25

Electronics Newsletter

Pentagon weighs use of satellites in limited war

The Pentagon is considering a quasi-tactical application for the longhaul strategic satellite communications system that will eventually replace the Initial Defense Communications Satellite System. The proposal calls for the use of individual synchronous satellites in the system as regional
communications centers in alimited war. The satellites would connect several ground stations in the theater of operations.
A Defense Communications Agency spokesman, Air Force Lt. Col. Ralph Backes, described ahypothetical regional system, called Seasat, for Southeast Asia satellite, at an American Institute of Aeronautics and Astronautics conference in San Francisco last week.

Tv interests gird for spectrum battle

Watch for broadcasting interests to wage alast-ditch battle to keep land mobile radio users from "encroaching" on frequencies reserved for television. It's now clear that the FCC will reallocate some uhf frequencies or will order channel sharing. The tv industry got the message this month
when FCC chairman Rosel H. Hyde, in his strongest statement yet on the issue, bluntly told the National Association of Broadcasters, "It's likely that additional use will have to be made of spectrum space allocated to television."
Broadcasters are planning to launch independent studies of land mo-
bile. They aim to stress to the FCC, Congress, and the public that the frequencies now assigned land mobile users are not being shared ef-
ficiently. They also want to push the FCC to study the possible use of higher frequencies for land mobile communications.

Alaska tries to put messages in orbit

Alaska is trying hard to get satellite communications service. State legislative and communications officials will talk in Washington May 1with representatives of the FCC, Comsat, the State Department, ana the
Presidential Task Force on Communications. Alaska could either build aground station and tie into the Pacific Intelsat system--which would allow communications to Washington State, Hawaii, and Japan and other Far Eastern points--or tie into the U. S. domestic satellite pilot system
expected to be in service by 1970-71. The domestic system is expected to be sanctioned in the next month or so.

Addenda
26

Computer manufacturers will lose many lucrative maintenance contracts on Government automatic data processing equipment if the General Accounting Office has its way. GAO, Congress's fiscal watchdog, contends that Government agencies could save money if they used their own computer maintenance personnel. Leaving out many specialized military computers, the GAO calculated that Federal agencies now spend about $50 million annually for maintenance contracts on computers owned by the Government. ...While foreign bids are still due on the giant Intelsat 4 communications satellite, one domestic firm has already released information on its bid. Lockheed Missiles and Space has proposed abarrel-shaped satellite 9feet wide and 16 feet high, weighing 1,075 pounds. ...Six unidentified firms have been asked by LockheedCalifornia to bid on the job of integrating the avionics hardware for its L-1011 airbus. That varies from the usual way of equipping commercial airliners, in which the airframe manufacturer negotiates with customers directly to meet their avionics needs.
Electronics IApril 15, 1968

Integrated
MU It

FROM SYLVANIA

increase computer speed and reliability. cut size and costs at same urne.
SM-60 4-bit storage regi5.ter

You get all these system improvements when you design around Sylvania monolithic digital functional arrays.
Sylvania monolithic arrays come in the fami:iar 14-lead package -- in-line or flat pack--you kr_ow so well with our SUHLTm circuits. Easy to plug into conventional circuit boards.
The big difference is packaging density--more functions per package, less pins per function and higher speed. Monolithic arrays, typical of today's most modern MSI (medium-scale integration) technology, give you in single compact units such basic computer subsystems as adders, frequency dividers, registers and memories which work at faster speeds, use less power, need fewer connections and cost less than discrete IC subsystems.
Table 1gives you an idea of the degree to which a computer can be simplified, reduced in size and made more efficient by use of Sylvania arrays.
In addition, our arrays significantly improve total system performance and reliability. Consider some of their advantages.
(Continued on next page)
Tins Issue in capsule
IC Types SUHLTm Iand II, the irdustry's fastest and most complete TTL line.
IC Packaging Molded plastic packaging lowers IC costs.
Hybrid Microcircuits Active trim assures repeatability at low cost.
IC Applications World's largest aircraft uses some of world's sma lest IC systems.
Manager's Corner LSI is on its way, but MSI .s here today.

TA:LE 1. MONOLITHIC DIGITAL FUNCTIONAL ARRAYS VS. CONVENTIONAL ICs

Typical Computer Subsystems
Basic Single Stage Fast Adder With Anticipated Carry64

Sylvania Monolithic Digital Functional Arrays

Number
of Packages

Number of Equivalent
Discrete Components

Speed (nsec)

Power (MilOwens)

NM" External
Connect'ns

Conventional Integrated Circuits

Equivalent Number of
IC Gates

11111111, Power
MilDwells)

101111/1 External
Connect'n

1

73

14

120

14

18

180

Four Bit Anticipated Carry Adder

4

292

35

.

480

56 ,

72

Ilk 720

252

Four Bit Ripple Carry Adder

4

264

60

400

32

36

P r 540

132

Eight Bit Anticipated Carry Adder

12

704

45

1040

168

172

1460

602

Eight Bit Ripple Carry Adder

8

528

120

800

Decade Frequency Divider

1

116

DC to 30 mHz

150

Four Bit Register (Bus Transfer Output)

1

87

15

120

112 r 6
12 . .

72

1 1080

40(C)

600(C)

25

350

252 140(C)
89

F(oCuarscBoitdeRePgulisltuepr Output)

1

94

15

120

11 '

25

lip 350

89

A) Based on Average of 15 mw per NAND/NOR and Average of 5mw per AND-NOR Expansion. B) Based on Average of 4Gates per 14-Lead Package.
(C) Using 4 Sylvania JKs and a Pulse Shaping Gate, the Package Count would be 5 and Interconnections 37. Average Power Drain would be 190 mw.

FUNCTIONAL ARRAYS, TYPICAL CHARACTERISTICS (+25°C, +5.0 Volts)

Function

Type Nos.

tr7:1 Avg. Power

(nsec)

(mw)

Full Adder

Dependent Carry Fast Adder

Independent Carry Fast Adder

Carry Decoder

Decade Frequency Divider

Four Bit Storage Register Bus Transfer Output

Four Bit Storage Register Cascade Pullup Output
16-Bit Scratch Pad Memory

L.

SM-10, SM-11, SM-12, SM-13 SM-20, SM-21, SM-22, SM-23 SM-30, SM-31, SM-32, SM-33 SM-40, SM-41, SM-42, SM-43 SM-50, SM-52
SM-60, SM-61, SM-62, SM-63
SM-70, SM-71, SM-72, SM-73 SM-80, SM-81, SM-82, SM-83

'Minimum toggle frequency "Minimum fan-out

sum 22 carry 10 sum 22 carry 10 sum 22 carry 10
2 30 MHz

20

20

.

25

125 125
25 120
30/bit
30/bit 250

Noise Immunity +(volts)--

"Military

**Industrial

(-55°C to +125°C) (0°C to +75°C)

Prime FO Std. FO Prime FO Std. FO

1.0

1 0

20

10

10

1.0

1.0

20

10

.20

:10

1.0

1.0

20

10

20

10

1.0

1.0

1.0

1.0

15

15

1.0

1.0

20

10

20

10

1.0

1.0

20

10

20

10

1.0

1.0

40

20

40

10

Integrated circuit structure for 8-stage fast adder.

46 B6

A, By

co
·ED., »Os.
e,
C4 Ca

:JO
ENT!

S7

a4 94

ENACRLEOASEDÍA W TUEe FASn T I I

-

e:

Ai Bi

A.

8o
t

PCS,FEARCRENTRVOIYPTOUNOtSgUGTAREDODODUFENRD

;MON I

I

f 1

a.

TEEXN-DER

1'

L

So

8-stage anticipated carry fast adder made from SM-20, SM-30 and SM-40 monolithic digital functional arrays.

B7 .7

Blf

SS Al

EN A4

B, 4,
4-4

Sh1-20

SMZ 40,

ACNNAETSRXITRTCAYI,PC`TAo-TO,ED

1114
CI · .9.8
mew
%ON co
4914 CO

9101-30 976 N-

51,430 40

EN.30

SY-30

-30

30 Sit

o

rt.

o

CAB···ACAUoAcGRcER,NY,Oo

s

54

A, Gay

iY 447

'-

Sea
--0ENTENDERS 0
I

This
NOW SUHLTM ICs in molded plastic uackages give you rummy olus economy.

More SUHL integrated circuits for the dollar, along with other advantages for you in performance and reliability. That's the big reason to consider these
TTL's now in anew modern molded plastic package.

plus this

pr.-.-..,-_....sseigssem by.

791r7mriTriut..., ry, !.;: wilrilUALL

9.

. rr 9 9499.1

,/ 411..11 /1 11

,
¡Me Melt

4:111143 s.4.401 se.fip7

fi

equals this
Complex Sylvania monolithic array (below, in 28-lead package) performs all the functions of the double-sided discrete-component IC circuit board, above. Available soon, it will be much more economical to produce in volume.
An array system puts more of its essential connections inside the basic 14-lead package. So there's less external wiring, and therefore a lower assembly cost, as the diagram (above) indicates.
Arrays provide more equivalent gating functions per pin: about 2gates per pin typical in our SM-60 fourbit storage register.
Because signal paths are shorter, arrays reduce propagation-delay time and give better control of t,-.1 paths.
An array design, as opposed to adiscrete-IC-board unit, has less backwiring. Shorter current paths reduce cross-talk, external noise pickup, self-induced (L ) noise as well as power-supply-decoupling requirements. And metallization assures better "dress" between individual components, and thus better control of intercomponent-connection electrical characteristics.
Sylvania now has, or is developing, arrays for every stage of acomputer:

Our SUHL circuits are still available in ceramic flat
packs and dual in-line plug-in packages. But now SUHL is available in molded plastic packages with glassivated wires and chips, providing an inert interface between the plastic and the active device ... a Sylvania extra. In this package, our SUHL circuits meet the needs of design engineers more economically than ever before.
SUHL types in this newest package include the
AND-NOR, NAND/NOR and J-K flip-flop families. All are temperature rated for operation over the 0-75°C range. The glass-coated chips are moisture-proof and
are fully protected from contamination by foreign matter. Heat dissipation capability is equivalent to that of aceramic flat-pack.
With the new molded plastic package, tinned rectangular leads are spaced 100 mils apart and are canted to facilitate automatic machine insertion in circuit boards.
Leads are attached to chips using aluminum-to-
aluminum ultrasonic bonding methods. Because there is no trimetal interface (silicon can represent the extra metal), there is no possibility of self-generated bond failure due to "purple plague".
And where cost economy is important, these units offer dependable SUHL circuitry at the lowest prices ever. Sylvania passes along to the user the savings accrued through more efficient assembly processes. So you get our familiar high-quality SUHL circuits in an efficient package at the right price.
CIRCLE NUMBER 301

MOW

ALUMINUM

PLASTIC

TO ALUMINUM

BONDED WIRES -\

CHIP

GLASS PASSIVATION LA

FRAME

TN PLATED IOVAR LEADS

Arithmetic

Control

Memory

Input/Output

Adders: SM-10, -20, -30, -40
4-bit universal shift register'

3CD* counter

16-bit scratch-pad memory, SM-80

Binary counter 4-bit storage register, SM-60, -70

BCD* to 7-line translator

'Presently in engineering development stage.
Our monolithic digital functional arrays -- their numbers and functions--are shown on page 2opposite. Tear it out and save it for reference.

CIRCLE NUMBER 300

SUHLTM Iand iiic's--the runaway favorites in TTLnow offer some 160 different types.

SUHL ITYPICAL CHARACTERISTICS (+25°C, +5.0 Volts)

Function

Type Nos.

WI
(nsec)

NAND/NOR Gates

Dual 4-Input NAND/NOR Gate

SG-40, SG-41, SG-42, SG-43

10

Single 8-Input NAND/NOR Gate

SG-60, SG-61, SG-62, SG-63

12

Expandable Single 8-Input NAND/NOR Gate

SG-120, SG-121, SG-122, SG-123 18

Dual 4-Input Line Driver

SG-130, SG-131, SG-132, SG-133 25

Quad 2-Input NAND/NOR Gate

SG-140, SG-141, SG-142, SG-143 10

Triple 2-Input Bus Driver

SG-160, SG-161, SG-162, SG-163 15

Triple 3-Input NAND/NOR Gate

SG-190, SG-191, SG-192, SG-193 10

.AND-NOR Oates

Expandable Quad 2-Input OR Gate SG-50. SG-51, SG-52, SG-53

12

Expandable Dual Output, Dual 2-Input OR Gate

SG-70, SG-71, SG-72, SG-73

12

Exclusive-OR with Complement

SG-90, SG-91. SG-92, SG-93

11

Expandable Triple 3-Input OR Gate SG-100, SG-101, SG-102, SG-103 12

Expandable Dual 4-input OR Gate SG-110, SG-111, SG-112, SG-113 12

Non-Inverting Gates .

Dual Pulse Shaper/Delay-AND Gate SG-80, SG-81, SG-82, SG-83

11

Dual 4-Input AND/OR Gate

SG-280, SG-281, SG-282, SG-283 11

AND Expanders

Dual 4-Input AND Expander

SG-180. SG-181, SG-182, SG-183 < 1

Dual 2 4- 3 Input AND/OR Expander SG-290, SG-291, SG-292, SG-293 7

OR Expanders

Quad 2-Input OR Expander

SG-150, SG-151, SG-152, SG-153 4

Dual 4-Input OR Expander

SG-170, SG-171, SG-172, SG-173 3

Flip-Flops

Set-Reset Flip-Flop

SF-10. SF-11, SF-12, SF-13

20MHz·

Two Phase SR Clocked Flip-Flop

SF-20, SF-21, SF-22. SF-23

20MHz·

Single Phase SRT Flip-Flop

SF-30, SE-31, SF-32, SF-33

15MHz·

J-K Flip-Flop (AND Inputs)

SF-50. SE-51, SF-52, SF-53

20MHz*

J-K Flip-Flop (OR Inputs)

SF-60, SF-61, SF-62, SF-63

20MHz*

Dual 35MHz J-K Flip-Flop (Separate Clock)

SF-100, SF-101. SF-102, SF-103

35MHz ·

Dual 35MHz J-K Flip-Flop (Common Clock)

SF-110, SF-111, SF-112, SF-113

35MHz ·

SUHL II TYPICAL CHARACTERISTICS (+25°C, +5.0 Volts)

NAND/NOR Gates

Expandable Single 8-Input NAND/NOR Gate

SG-200, SG-201, SG-202, SG-203 8

Quad 2-Input NAND/NOR Gate

SG-220, SG-221, SG-222, SG-223 6

Dual 4-Input NAND/NOR Gate

SG-240, SG-241, SG-242, SG-243 6

Single 8-Input NAND/NOR Gate

SG-260, SG-261, SG-262, SG-263 8

iiu-rsOR Gatelye........mirmer·-,1,-------,.---,

.' Expandable Dual 4-Input OR Gate
Expandable Quad 2-Input OR Gate Expandable Triple 3-Input OR Gate .Expandable Dual Output Dual -..,2zeput Qa,pate AND Expanders Dual 4-Input AND Expander
OR Expanders
Quad 2-Input OR Expander Dual 4-Input OR Expander Flip-Flops Dual 50 MHz J-K Flip-Flop
(Separate Clock) Dual 50MHz J-K Flip-Flop
(Common Clock)
50MHz J-K Flip-Flop (AND Inputs)
50MHz J-K Flip-Flop (OR Inputs)

SG-210, SG-211, SG-212. SG-213 7 SG-250, SG-251. SG-252. SG-253 7.5 SG-300. SG-301, SG-302, SG-303 7
- ,gi.,731:1A31Z Sq31,3 _ 7
SG-180, SG-181, SG-182, SG-183 < 1
SG-230, SG-231, SG-232, SG-233 2 SG-270, SG-271, SG-272, SG-273 2

SF-120, SF-121, SF-122, SF-123
SF-130, SF-131, SF-132, SF-133 SF-200, SF-201, SF-202, SF-203 SF-210, SF-211, SF-212, SF-213

50MHz*
50MHz · 50MHz' 50M1-1z ·

Avg. Power (mw)

**Military

Noise Immunity (-55°C to +125°C)

+(volts)--

Prime FO Std. FO

**Industrial (0°C to +750C) Prime FO Std. FO

15

1.1

15

1.1

15

1.1

30

1.1

15

1.1

15

1.1

15

1.1

30

1.1

20/gate

1.1

35

1.1

25

1.1

20

1.1

30/gate

1.1

38/gate

1.0

0.9/gate 1.1

15/gate

1.0

20

1.1

5

1.1

30

1.1

30

1.1

30

1.1

50

1.1

55

1.1

55/FF

1.0

55/FF

1.0

1.5

15

1.5

15

1.5

15

1.5

30

1.5

15

1.5

15

1.5

15

1.5

15

1.5

15

1.5

15

1.5

15

1.5

15

1.5

15

1 5

10

1.5 1.5

1.5 1.5

1.5

15

1.5

15

1.5

15

1.5

15

1.5

15

1.5

11

1.5

11

7

12

6

7

12

6

7

12

6

15

24

12

7

12

6

7

12

6

7

12

6

7

12

6

7

12

6

7

12

6

7

12

6

7

12

6

7

12

6

5

8

4

7

12

6

7

12

6

7

12

6

7

12

6

7

12

6

6

9

5

6

9

5

22

1.0

22

1.0

22

1.0

22

1.0

-

30

1.0

43

1.0

36

1.0

30/gate

1.0

0.9 gate 1.1

28

1.0

6.7

1.0

55/FF

1.0

55/FF

1.0

55

1.0

55

1.0

1.5

11

1.5

11

1.5

11

1.5

11

1.5

11

1.5

11

1.5

11

1.5

11

1 5

1.5

1.5

11

1.5

11

1.5

11

1.5

11

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

6

9

5

MONOLITHIC LINEAR AMPLIFIERS TYPICAL CHARACTERISTICS (+25°C)

Function

Type Nos.

Wide Band Video Amplifier

SA-20, SA-21

High Gain Operational Amplifier SA-40, SA-41 SA-42, SA-43

Amplifier/Limiter/Discriminator SA-500, SA-501

Supply Voltages
+24V
+12 to +6 and --6 to --3
+10 to +5.5

Power Dissipa-
tion (mW)
450
80/40
125

Input Imped-
ance 1.6K 25K
2.5K

Output Imped-
ance 1.5 125
15K

Output Signal Swing Vp-p
13.0
10.0
2.8

--3db Freq. MHz
100 1.2
6

Voltage Gain (db) 21 69
75

Temperature Range
--55°C to +125"C
--55°C to +125°C 0°C to +75°C
--55 °C to +125°C

Our Sylvania SUHL Iand Il lines offer you more different types of TTLs to do more different jobs --faster and better--than any comparable TTL
line in the industry. For your convenience, the
list (left) is color-coded to the IC diagrams on this page. Tear it out and save it for reference.

Applications engineers estimate that 80% of new computer designs call for TTL. And our SUHL line--Sylvania Universal High-level Logic--is the industry's acknowledged leader in TTL, the line that other manufacturers admit to copying.
Speed is the most important advantage, of course. Our SUHL II flip-flops, for example, provide up to 50 MHz switching speed, as little as 6 nsec propagation delay time (tFI)while retaining extremely high noise immunity.
Shown here is a full list of SUHL I and II TTL logic elements available to you, all colorcoded to the appropriate diagrams. (The chart at bottom, listing linear amplifiers, is not color coded.) Our monolithic digital functional arrays are listed on page 2with an article on the subject.
SUHL circuits are still the fastest TTL's; in addition to maintaining good switching speeds, they keep waveform integrity under varying loads and fluctuating temperatures.
Every Sylvania rri, element is fully and automatically tested on our specially designed Multiple Rapid Automatic Test Of Monolithic Integrated Circuits (MR. ATOMIC) equipment to assure that you get the performance you pay for every time. All units, except as noted, are available in 14-lead flat-pack style or dual in-line plug-in packages.
CIRCLE NUMBER 302

.

41

1 ;-

--

j.

.i ·· , · a · · ·

i::A 1.......filil 1 III)

te è ;S 14 #1 1)11 1 1.1.-,1S

---.

j

Lti

-- --Ii

ii,,...-.I..,,..,,

.,

· r .:. III

.·ii , .11-,-- , :: . s·.!.., · ·i,

. ..-)

I

ii ·

.

- ,1 illke-,;;1;,-t,·-f.,- I.,i 1¡II

;1! !'.\,.. ..7,..1`..: ..J,./ Iiil ';'-·* · '-

kiii.r .-..,,,..,·. ,,,, ill .··.,...-.--.i-... I!;:i.It,!i-·=···7·e;,.,u..

·
---

--

n ·,im. '' !: ·--7,1.q.. . --

u·-·.,',, ··.·--..,1,.li11i1.,,1 / 4.,-,.._: ' 1

_,.

¡¡¡'" .¡....--· *._J._.:i_ -:i::..`..#-.,.·,..J...,,4., I1.Ii.. I1,'Ii,_r,1,·:-.11

".) .7.- "..--2-. 1''.: .-.-Y,-,...11.11rI:e;.i. 1i_p 1

-- III !. 9)

iiIlvii:.--· ., ;'.Ii:.Ll-e.-a

. 11.1.!!.)..'.'....:r.:::/.,i,..-...\: J'-i:l.ji...1",.,...,:;j ·/"-4..:

111

3.1111 -"mil

JI

SM-80, 16-bit scratch-pad memory.

Basic NAFL/NDR Gates
14 ·
-- 13

3 vce )4
5

- 12 -- 11
r 10 g

8

AND-NOR Gates

111 191
(11) 1111 1,, (71

SC1111 TIFX1n1t-

Non-Inverting Gates
1 ·
2 3
iv,, 4

14 13 12 11 10
9
a

AND Expanders
14 ·
13

3

12

Iv& 4

11

5

10

6

8

OR Expanders

r-- (14) SETA
(1 ) KA (3) CA (2) JA
(6) Je (5) Ce (7) Ka (8) SETe

Flip-Flops Gk(13)

(Ks) 1 (Ku) 2

I--QA(12)
I -- Cleao
iQe (·9)

(CLOCK) 3 (vec ) 4
(Ji) 5 (J2) 6

(J3) 7

14 (Ks)
13 (0.C. RESET)
12 CO
11 (0)
10 9 10£. PRESET) 8 (PC -
SET)

Custom microcircuits: repeatability at low cost through active trim.

Now, through active trim of hybrid microcircuits, Sylvania can meet exact requirements for repeatability of quiescent DC level balance.

Figure 2--Equivalent circuit diagram of photocell signal amplifier.

Until recently, electronic circuit designers would first

select circuit topology and then, to fulfill their specific requirements, would compute active and passive device values. With that approach, circuit performances could fall within a wide range of values, sometimes resulting in poor production yield.
To improve yield, previous options open to the de-

acter recognition system where the quiescent DC level from amatrix of cells has to be balanced. A requirement is that the output of each amplifier must be held at afixed DC value from unit to unit. The actual circuit is shown in Figure 1. Figure 2 is an equivalent schematic.

sign engineer were either to select tightly toleranced

The output voltage level is established by the output

components or to specify adjustable elements to bring of adifferential amplifier. The emitters of the differ-

circuit performance within acceptable limits. These ential transistor pair (Q1 and Q2) are connected to a

choices often lead either to relatively higher cost or to transistor current source (Q3). The level of current is

larger package size.

fixed by the values of resistors R3 and R4 to set abias

But now, with the conventional microcircuit, for Q3.

Sylvania individually trims passive components to After all required adjustments have been made, this

final value through the use of anull-detecting bridge. Passive component trimming can achieve the desired circuit performance characteristics.
Final adjustment is effected after active components

circuit is energized and R4 is adjusted to apredetermined value of output voltage. Since in the thick film technology screened resistors are fired to value below the desired nominal, R4 may be increased in value by

have been attached and after the circuit has been energized. During this final trim, the rate and amount of abrasion is controlled by monitoring the circuit characteristic of interest. This trim allows the circuit designer to work with broader tolerance of individual circuit elements. Such atechnique can be cost-effective

using air-abrasive trim techniques to effect ageometry change. As the value of R4 is increased, the operating point of Q3 is changed causing the increase in collector current. As the voltage drop in R2 changes, DC level at the output of the emitter follower approaches the required level.

since in-process yields are substantially increased as individual component tolerances are relaxed.
As one example of an active trim application, let's take aphotocell signal amplifier. It is used in achar-

This represents just one example of how Sylvania meets the need for inexpensive hybrid microelectronic circuits tailored to your operational requirements. CIRCLE NUMBER 303

Figure 1--Air-abrasive trim techniques are used to precisely adjust circuit operating characteristics.

Largest aircraft will rely on some 01 world's smallest, fastest ICs: Sylvania SUIVII.
World's largest aircraft, U.S. Air Force C-5A Galaxy built by Lockheed-Georgia Company of Marietta, Ga., employs Sylvania SUHL Il high-speed IC logic elements in its self-checking Malfunction Detection, Analysis and Recording (MADAR) subsystem, its station-keeping equipment (SKE) radar subsystem and its landing gear proximity switch control units.

@sit iteirefli

I II

ILI1&L1L1L1Li5E1LoiiIl

One of ten printed IC mounting boards used in Galaxy's stationkeeping equipment (SKE) synchronizer.

The Lockheed C-5A Galaxy will not only be the world's largest aircraft. It will also be one of the world's most self-sufficient.
Through its Malfunction Detection, Analysis and
Recording (MADAR) subsystem, the aircraft continuously monitors over 600 critical test points during takeoff, flight and landing. If adefect occurs, the defective subsystem's number lights up on the flight engineer's
instrument panel. Then for a diagnostic check, the flight engineer calls for a live waveform and views it adjacent to comparative ideal waveforms projected on
a screen from a random-access memory bank, and takes corrective measures. And as he makes manual
diagnoses and corrections, MADAR continues monitoring other test points automatically.
The MADAR subsystem is designed around Sylvania
SUHL II ultra-high-speed integrated circuits. Our SUHL II ICs also accomplish essential logic functions in the synchronizer unit of the aircraft's station-keeping equipment (SKE) and in the landing gear prox-
imity switch control system. The SKE system is alowfrequency (doppler) radar which automatically main-
tains the correct relative flight position of every aircraft in afleet. The landing-gear proximity switch senses the position of the landing gear and landing-gear housing doors, controls their sequence of operation and informs the crew of any malfunction.
The MADAR control and sequencer uses about 450 SUHL II ICs; the SKE synchronizer has some 378.
How important are they? Says Lockheed: "By using integrated circuits and ...thick-film hybrid circuits, the size and weight of these systems
has been greatly reduced while reliability increased. Development of either system without integrated circuits would have been impractical; the complexity of

Artist's conception of C-6A in flight. Aircraft is designed to carry 100,000 pounds of payload for 6300 miles, and up to 265,000 pounds for shorter distances. It will be 82 yards long with a wingspan of 74 yards.
discrete component designs, to accomplish the required logic functions, would have resulted in units too large and heavy and too unreliable to use on aircraft."
What more can we say? CIRCLE NUMBER 304

Use Sylvania's -Hot Line" inquiry service, especially if you
require full particulars on any item in a hurry. It's easy and it's free. Circle the reader service number(s) you're most interested in; then fill in your name,
title, company and address.
We'll do the rest and :Jae you get further information by return mail.

BUSINESS REPLY MAIL
No Postage Stamp Necessary if Mailed in the United States
POSTAGE WILL BE PAID BY
Sylvania Electric Products Inc. Sylvania Electronic Components 1100 Main Street Buffalo, New York 14209
Dept. C4 4

FIRST CLASS Permit No. 2833 Buffalo, N.Y.

MANAGER'S CORNER
LSI...around the corner. But tat is here now.

We've all heard tales of the girl who rejects the nice

boy next door while she waits for Prince Charming ...

and winds up an old maid.

Right now in the computer business, medium-scale

integration (MSI)--in the form of monolithic digital

functional arrays--is in the position of the nice boy next

door, while LSI is Prince Charming.

MSI devices are something we make and you can use

--today, without redesign of your present circuit

configurations. LSI is still in the future both as to volume manufacture and practical application.

Sylvania LSI chip: over 1200 components, 100 logic functions.

There's an unfortunate tendency in this industry to about a technique in which--on a 500-gate 2-inch

"announce" something when it's on the drawing board, wafer--by selection and rejection only functioning

and to say it's "in stock" when aprototype has been gates are wired. This could yield 400 or more functions

produced. (By that definition, Sylvania could claim in asingle package ... the beginning of the "computer-

we have LSI devices "in stock", because we have pro- on-a-wafer" concept.

duced and are testing prototypes with over 100 func-

But such devices--to produce in volume and to be

tions on achip.) But we don't believe in that; when we used practically--will require much more sophistica-

say we have something "in stock", we mean we have a tion on the part of both manufacturer and user than

device that works and that we can deliver in quantity the present state of the art permits. To produce them

within amatter of days.

will require the ability to create an extremely high

And we do have MSI devices in stock. Such devices yield of usable functions on awafer, excellent control

will be the basis of practical computer designs for the of multiple-layer interconnection techniques and very

next five years or so. Any computer manufacturer who complex testing and packaging procedures. Equipment

passes up MSI to wait for LSI is likely to find himself and process requirements will be elaborate and costly.

in the situation of the girl waiting for Prince Charming.

More significantly, the engineering required by the

Left out.

computer designer, builder and user must be advanced

Our MSI monolithic arrays, available in the familiar to afar higher level than present technologies demand.

TO-85 14-lead flat pack or 14-lead dual-in-line plug-in Builders must understand the importance of these dif-

package, provide in general from 20 to 50 gating func- ferences before committing themselves to an approach.

tions on asingle chip with asingle layer of metalliza-

So ...LSI is coming. But meanwhile, MSI in the

tion. These devices are fully compatible with existing form of functional arrays is the practical solution to

monolithic logic; they interface with present-day systems without major redesign effort on your part.
Larger-scale integration--which we're working on-- refers to afunctional device with more than 100 functions, created by multiple-layer interconnections using metallized fixed connective patterns. This will bring

today's computer design problems.
eimedvic,
H. M. Luhrs Product Marketing Manager Integrated Circuits

SYLVAN IA 'fflfflIgPr

This inforZion in Sylveffigras is furnished without assuming any obligations.

^ duURIViAL TELEPHONE &ELECTRONICS
CTRONIC TUBES · SEMICONDUCTORS · MICROWAVE DEVICES · SPECIAL COMPONENTS · DISPLAY DEVICES

C4

NAME TITLE COMPANY ADDRESS CITY

STATE

ZIP

Circle Numbers Corresponding to Product Item

300

301

302

303

304

El Please have a Sales Engineer call

HOT LINE INQUIRY SERVICE
Need information in a hurry? Clip the card and mail it. Be sure to fill in all information requested. Well rush you full particulars on any item indicated.
You can also get information using the publication's card elsewhere in this issue. Use of the card shown here will simplify handling and save time.

I'm tough
And 15,000 hours says I'm tough

Clifton's long life synchros have exceeded 15,000 hours of continuous testing and remained within specification. Clifton will guarantee a minimum of 5,000 hours for almost any application and, depending upon the end use, may guarantee them much longer.
These synchros retain all the high accuracy or torque of standard Clifton synchros. In fact, you can order them right out of the Clifton catalog without forfeiting a single catalog parameter except friction which is raised slightly. NO PENALTY in phase shift, impedance
Electronics lApril 15, 1968

angle, torque or input power and only aslight increase in cost over standard synchros. Compare these features with other long life synchros on the market today.
For further information call your local Clifton Sales Office or 215 622-1000 or write 5050 State Road, Drexel Hill, Pa. 19026.
CLIFTON 11
DIVISION OF LITTON INDUSTRIES

Circle 35 on reader service card

35

When the name of the game is

.0e 1 .,.3 . *t'i/

,s;.·.'h ·...0Y'',Ys',''Y'A,,f·r,,r-XXse.eey,ts\esi.scetesix)s:iCXPL,:·/,),

AAI'.15) 24 #
9 7

Ii je'at's's'i.,'ie-s,e's'',e',0.teir.,,sY1X..X,XXX'X'X'X',,X%%XIX.XY,.X .t·

ssi:Y.Y...Y.Y.XI.IC,

d.·

',',XXXXxx

èYs)(I·%

01% %.

II I %

i

AMER Gli IAQV

41111P

Type MMC. 1/20 watt. RNR50

Type CCM. 1/10 watt. RNR55

No one matches the performance superiority of IRC metal film resistors, or their capability and flexibility to meet avariety of reliability requirements.
Take these four sizes, for example. They meet or exceed all of the performance and environmental requirements of both MIL-R-10509 and MIL-R55182. Standard tolerances are as tight as ±0.10% (±0.05% on specials) and temperature coefficients are as close as ±25ppm/°C.
When the best military grade resistor isn't good enough, and the screening route to increase survival probability has been decided upon. IRC has the capability, the facilities and the experience to deliver resistors screened to any meaningful specification. The best can be made better.
If the best must be better yet. IRC, under its Program for Assured Reliability, can also supply

36

Electronics !April 15, 1968

IRC is in a league by itself

XXX

-V

XX XXX XXX kX):XXXX'

XX XXX XX> XXXXX> X

C·r-A ·
Type CCA. 1/8 wait. RNR60

I_

f

Type CCB. 1/4 wait. RNR65

/

these four units to meet your choice of three maximum failure rates-

0.1%, 0.01% and 0.001%. Failure rate levels depend on the degree of

screening, process control, acceptance, and life tests required.

When your design requires reliability--be it screening, control, data, or documentation (or any combination)--look to IRC to supply metal film resistors matched to your cost and peiformance needs.

N'1W APPLICATIONS HANDBOOK. Ask for a copy of "An

Analysis of Screening "This informative handbook explains all the

techniques employed by IRC to achieve varying degrees of resis-

tor reliability.

019

For samples, prices, and data on any IRC metal film resistors, write: IRC. Inc., 401 North Broad Street, Philadelphia, Pa. 19108.

DIVISION OF TRW INC.

Electronics IApril 15, 1968

Circle 37 on reader serv.ca. card

37

New connectors. New standardization.

JT concepts have really branched out at Bendix.

Now--to the thousands of JT users who like the advantages of rear-release crimp contacts-- Bendix offers the opportunity to standardize. It'll ease operation, installation and maintenance problems in the field. Cut back on spares and application tools. And you'll enjoy the inherent benefits of size and weight savings, reliability and extended con-
nector life. You liked rear-release crimp contacts so well, we're putting them in all kinds of connectors in all kinds of shapes. Rectangular connectors, cylin-

drical connectors, printed circuit connectors, rack and panel connectors. All with solder or filter contact options. A full variety of shell sizes and types. Many insert patterns with 12-, 16-, 20-, 22- and 22M contacts. Double-density models with up to 128 contacts. Plus some entirely new designs coming your way soon. If you haven't tried them by now, you should. They'll grow on you. Write Electrical Components Division, The Bendix Corporation, Sidney, New York 138:38.
two Bendix Electronics

38

Circle 38 on reader service card

Electronics April 15, 1968

ere

pirse4oe0u-·-Pe4`.\

.k-i·ii=3.-#

%
r

operm..*

.....,,,

,,,...,,-- ,-.,.. /I \ t, ' . \

.Ae

--- irmipe iii--. ._1.0,inem...,......_ \ i,i *"i'et-:'I'.`" 'flk

,-,-ee iiiiii _

ii.\, \ `

/ \

1

\ )

''''ap N.

/

'''·,,-.ed&-, `

*.'s .4 i

'fie

% %1.*%`% `1'41._,I

,/ 1-1

i

%` 0.\\\ / v

\` aer,...".f.r..i.e.sr0.e7'r)---- ....-.-

\0A. lf

\

.1t1;i

//.
`

if

tekti

\

(\t \

'
..

hp i)/ .4/I,e'/b,t,e,

t

111

49e/

MEET THE DECISION MAKERS...

CVC

Four CVC High Vacuum Systems with AutoMate" Control!

Just touch the start button, AutoMate does the rest. The AutoMate Control on your CVC system controls pumping cycles automatically--as fast and accurate as your best technician. The cycling decision is

made and carried out in response to pressure in the system--you get the same results in your pumpdown every time. For full details, write Consolidated Vacuum Corporation, Rochester, New York 14603.

CV-144

CV-164

CV-18

CV-1104

APPLICATIONS

Electronic and Optical Thin-Film Deposition, Environmental Studies

Electronic and Optical Thin-Film Deposition, Environmental Studies

Electronic and Optical Thin-Film Deposition, Environmental Studies

Electronic and Optical Thin-Film Deposition, Environmental Studies

CHAMBER

14" Pyrex Bell Jar

DIFFUSION PUMP

4" BlueLine

18" Pyrex Bell Jar
6" BlueLine

18" Pyrex Bell Jar
6" BlueLine

24" or 30" Stainless Steel Bell Jar
10" BlueLine

BAFFLE

Choice of multicoolant or liquid nitrogen

Choice of multicoolant or liquid nitrogen

Choice of multicoolant or liquid nitrogen

Choice of multicoolant or liquid nitrogen

EVAPORATION POWER SL "'PLY RATING (Continuous Duty/20% duty)

2 KVA/3.9 KVA

2 KVA/3.9 KVA

2 KVA/3.5 KVA

4 KVA/8 KVA 1111

C V C
A BELL & HOWELL COMPANY

New CV-1104 System With AutoMate' Control

BELL Ei HOWELL

40

Circle 40 on reader service card

See us at NEPCON East Booth 324 June 4-6, The Coliseum Electronics IApril 15, 196£3

save installation time! save panel space!

with Allen-Bradley terminal blocks factory assembled in 6-foot lengths

Yes, Allen-Bradley factory assembles 6-foot sectons of Bulletin 1492 terminal blocks for your convenience. You save on installztion time because you don't perfcrm the time-ccesuming blockby-block assembly. Merely count the required number of mounted terminals, slide them beyond the eni of the solid wooden backing strip, and snap off as shown. Thz notched metal mounting channel breaks cleanli--no sawing or filing.
Further, these sturdy white rylon terminal blocks are real space savers. A wide variety of tzrminals is avai:able to handle wire up to Size 1/0. Fuse block: and switches are also avalable. For 600-volt jobs Style C Dlocks are supFhed, while even more comract Style Fblocks are used for 300-vit applications. Both Styles C and F mount on :dentical channels. By the way, individual blocks can be removed easily witl-out disturbing adjacent bocks so assemblies can be modified quickly to meet the changing job needs.

Your local Allen-Bradley appointed distributar has these 6-fcot lengths of terminal blocks in his stock. Please contact him so that he can show you their many features. Or wri,:e to Henry G. Rosenkranz, Allen-Bradley Co., 110 W. Greenield Ave., Milwaukee, Wisconsin 53204 and ask for Publication 6109. In Canada: Allen-Bradley Canada Ltd. Export arEce: 630 Third Ave., New York, N. Y., U.S.A. 10017.

1067M-8
Circle 41 oireader service card

ALLEN-BRADLEY
QUALITY MOT CR CONTROL

Meet the MICRO SWITCH QualityAssurance
Department

Left to right: vice president, design engineer, computer programmer, punch press operator, and shipping clerk. Not present for picture: All the other employees of MICRO SWITCH.

Quality Assurance for the customer is everyone's business at MICRO SWITCH. It is the result of atotal concern for the details that make up customer satisfaction. It starts with top management and permeates the entire organization, involving every step of manufacture--from raw materials and design on through production and shipping.
The emphasis at MICRO SWITCH is on the prevention of defects, rather than simply their detection.

The Quality Assurance program is designed to assure reliability before manufacturing begins. It includes such procedures as: aperiodic calibration system for all measuring equipment, a strict vendor rating system, extensive documentation to cover all details in advance, and innovative operator self-checking procedures.
Most important, our experienced, highly trained personnel have apersonal concern for customer satisfac-

tion. They know it's the little things that count.
What does this elaborate program mean to you? Dependability. The knowledge that each switch will hold up as well in your equipment as it does in our grueling laboratory tests. We're more careful to make you more sure.
To find out for yourself the many ways MICRO SWITCH is more careful, write for our booklet, "Quality Assurance for our Customers." No obligation, of course.

MICRO SWITCH

FREEPORT, ILLINOIS 61032
A DIVISION OF HONEYWELL
HONEYWELL INTERNATIONAL ·Saies ono service offices in all principal cities of the world. Manufacturing in United States, United Kingdom, Canada, Netherlands, Germany, France, Japan.

42

Circle 42 on reader service card

Electronics April 15, 1968

THIS BOOKLET CONTAINS COMPLETE DATA, PLUS "HOW-TO-USE" IDEAS FOR THE WORLD'S MOST ADVANCED I/C LOGIC FAMILY!

IT'S YOURS FOR THE ASKING!
Most data brochures contain specification sheets for all of the devices in the line. So does this one -- for 56 MECL* Il integrated circuits (29 different circuit designs). But, it also includes applications information, right on the data sheet, for each circuit. And, that's not all ... there's 10-pages devoted solely to the unique and interesting design philosophy of emitter-coupled logic. Then, to make it the highly-practical design tool that it is, this new MECL Data Brochure is designed for perpetual updating ...New circuit information can be added easily; and, there's room for the MECL 300/350 series brochures that are currently in use.
Yes, the MECL Data Brochure is Extraordinary in many ways ... but then, so is the MECL line of integrated logic circuits. We felt that the world's fastest, most-advanced full compement line of digital integrated circuits deserved more than just ordinary technical data treatment ...so, we prepared this special approach for you.
It's Yours for the Asking! Just drop us aline on your company letterhead, at P.O. Box 955, Phoenix, Arizona 85001.
°Trademark of Motorola Inc.

-ideze Aueeêem ifrpexliatt eade!
Electronics April 15, 1968

MOTOROLA
Semiconductors
43

Aword to the do-it-yourself module builder:

Don't.

Buy our JSeries modules instead.

The JSeries is our new family

of general purpose, all integrated

circuit logic modules. Their per-

formance almost matches that of our famous T Series modules,

These will cost you less.

but they cost about 25% less. They're made to the same

dimensions as the T Series, with the same 52 pin connec-

tors, so they're physically interchangeable. We make them

for our own seismic recorder systems, so they're rugged

and reliable. Now, as of January, you can buy them (corn-

Circle 44 on reader service card

plete with mounting hardware, racks and power supplies,

if you wish) in any of 25 different functions.

And save yourself the time and cost of making your

own: designing, assembling, testing, new procedures, new

equipment, new personnel, additional training, to say

nothing of the added paper work.

If you're building systems, you

must have better things to do than go

into the module assembly business.

Such as reading our JSeries catalog.

It's free.

Scientific Data Systems, Santa Monica, California

April 15, 1968
Electronics Review Vclume 41 Number 8

Integrated electronics
Plastic IC's still 4-F
Despite manufacturers' claims about the ruggedness of plastic-packaged integrated circuits and their suitability for military applications, the Pentagon remains unconvinced. Reliability testing by Government groups, though not exhaustive, has failed to establish a basis for acceptability, according to defense officials.
But the prospect of realizing tremendous cost savings by buying plastic-encapsulated devices in place of metal-can versions has prompted the Government to call ameeting of solid state experts to tackle the question. The experts will be asked to come up with an answer, or at least abasis for evaluation.
Charged atmosphere. The conference, at which Federal officers and makers' representatives will confront one another, promises to be stickier than one might suspect. The ordinary give-and-take of such meetings will he inhibited not only by the conferees' widely differing viewpoints, but by earlier insinuations of incompleteness in the claims made for plastic Ic's and by pressure from the higher echelons of Government.
On the Government side will be representatives of the armed services, NASA, the Army's Harry Diamond Laboratories, and the Jet Propulsion Laboratory, among others. Among the companies invited to the mid-May meeting in Washington are all the vendors of plastic lc's, including the big four--Texas Instruments, Motorola, Fairchild, and Signetics--plus such users as Autonetics, which, incidently, has been conducting extensive tests on the devices for the past few months.

[Electronics, April 17, 1967, p. 101]. under less than worst-case condi-

Background. Plastic-encapsulated tions.

ic's, which have been around for a No yardstick. However, since

few years now, have recently been there are no specific standards for

aggressively promoted by many lc performance, and because each

makers for use in military jobs now Government service and agency has

open only to metal-can circuits. its own reliability criteria, the issue

These firms implied that the de- can't be easily resolved. In fact,

vices' moisture resistance, while not some Government spokesmen indi-

as good as that of the hermetically cate an acceptance of the plastic

sealed metal-can units, was suffi- packaged product based on the spe-

cient for most applications.

cial needs of their department or

Since the plastic ic's usually cost agency. The Government's attitude

only half as much as their metal- right now seems to be that the plas-

can counterparts, Government pur- tic units can't be flatly rejected on

Fracture. Stress caused by shrinkage is serious enough to snap the interconnection wires on this plastic-packaged IC. Note the crack
(dark oval) around the package.

chasing agents, beset by budget problems, have strenuously urged their acceptance by the various Federal groups responsible for reliability evaluation. But these groups have tested them under conditions the metal devices must withstand, and have found that the plastic units fail in most cases, usually be-
cause of an insufficient moisture barrier. The failures occur typically after long-term (560 hours or more of operation) testing, indicating a cumulative breakdown. The failure rate is often 100%, even after months of satisfactory performance

the basis of the tests made so far, and that future evaluation programs should be carried out in amore coordinated manner than the earlier tests.
This general attitude won't lighten the atmosphere at the meeting. One Government official asserts that the absence of published results of long-term testing by makers is "fairly clear evidence that the plastic lc's still aren't suitable." He also criticized the short-term testing the firms do as unrealistic, and said that "if makers invested as much money into the plastic materials as

Electronics !April 15, 1968

45

Electronics Review

they spend promoting the Ids,

they'd probably come up with a

suitable encasement."

Cloudy specs? The producers, on ·

the other hand, continue to imply

t

that plastic devices can handle most military tasks. Some have ven-

I. red,

· eter--°`

'

la- ·

tured that the specifications the

Government issues are unrealistic

and stem from the days of vacuum

tubes.

One executive expressed the in-

dustry's view this way: "On the one

hand, Uncle Sam tells us to use

state-of-the-art devices, and the Pentagon issues adirective encouraging the use of microelectronics.

On the chip. Motorola will soon offer this large-scale integrated eight.
bit adder as part of its regular line. The circuit contains 448 components.

On the other hand, we're instructed

to use qualified parts wherever pos- line is an eight-bit adder that has is perpendicular to the plane of the

sible and we're confronted with 448 components laid on a 53-by- leads, which serves as both ather-

specs that were set up for older 119-mil chip using a three-layer mal and electrical connection. "To

technologies, or by no specs at all." metallization scheme. Walter Seel- remain flexible," explains Seelbach, bach, Motorola's manager of lc re- "and to be able to dissipate more

search and development, estimates power down the road, we had to

the adder will be ready for produc- have better thermal characteristics

First with the fastest

tion in the third or fourth quarter. in the package. Only about 7° C He said the line will also eventually per watt are dissipated between the

Engineers at the Semiconductor include such entries as a scratch- chip junction and the end of the

Products division of Motorola Inc. pad memory array and a left-to- stud. Standard flatpacics without

have been working for some three right shift register. "But for the first the stud dissipate between 100°

years toward the one-nanosecond half of this year we'll be concentrat- and 200° per watt inside the pack-

speed capability they think ultra- ing on the initial three parts."

age. If the user mounts properly to

high speed computers will require.

Seelbach thinks Motorola is six the stud, he could get as little as

Now it appears the division will months to a year ahead of other 25° per watt dissipated in the pack-

be the first supplier to break that semiconductor manufacturers in age."

barrier with a line of integrated this ultrahigh speed capability. He

Michael Callahan, manager of re-

circuits--the first three devices in describes the market for 1%1E0, 3as search and development for lc de-

its third-generation emitter-cou- "trememdous."

vices and processes, cites some of

pled-logic family. Later, the family

Seelbach also believes there will the processing sophistication re-

will include at least one device in- be amilitary market. But now MECL quired to reach a speed of one

corporating large-scale integration. 3will be specified for temperatures nanosecond. "We had to develop

The first entries in the MECL 3line ranging from 0° to 75° C--short of shallow junctions--less than one-

[Electronics, Nov. 13, 1967, p. 26] the --55° to 125° specified by the micron deep except for collector-

are now in pilot production and military.

substrate junctions. Most other

initial orders will be filled from this

High toggle frequency. "Hooked current-mode logic junctions are a

operation.

up as abinary counter, the flip-flop little deeper. Deposition also re-

For now, Motorola will introduce will be able to toggle in the 350-to- quires tight controls. Aluminum

adual four-input OR/NOR gate with 400-megahertz range," Seelbach tends to go into solution with sili-

a typical propagation delay of notes. He says the previous high in con and we don't want this pene-

about one nanosecond into a 50- toggle frequency in production cir- tration. So we use aluminum alloys

ohm load; a quad two-input NOR cuits is the 85-Mhz figure at which that slow down this tendency and

gate with the same properties and Motorola's MECL 2line is specified. limit the metal's penetration."

amaster-slave flip-flop exhibiting a He adds that the 50- and 500-ohm

Keep them small. Callahan says

maximum delay of 1.5 nanoseconds terminations for the dual four and that individual transistors in the

into a 50-ohm load. With lighter quad two devices are equivalent to lc's must operate at 1 to 2 giga-

loads-500 ohms at 5.2 volts--both direct-current fanouts of 12 and 4, hertz, and must be very small to

the dual and the quad will show respectively.

minimize the junction capacitances

atypical propagation delay of just

Each of the three devices will go essential for high speed. Resistors

0.8 nanoseconds. Both devices have into a 170-by-250-mil hermetically must also be small. "The largest is

only one layer of metallization; the sealed ceramic flatpack having 14 0.5 mil wide to keep parasitics

flip-flop uses two layers.

leads. The package design, new to down."

On schedule. Further down the Motorola, incorporates a stud that

Regarding passivation, he ex-

46

Electronics IApril 15, 1968

Electronics Review

plains further that oxide integrity keting at the Phoenix division, has

is "excellent--less than three pin- been abig jump in demand from

holes per wafer on the average. hybrid-circuit suppliers in the past

When we first started, pinholes year. He says this demand has

were 10 times greater and we had been fueled mainly by the mili-

to monitor every run. We're now tary's desire to integrate.

down to monitoring just once a "Monolithic lc's can't meet all

day." Motorola won't reveal yield the requirements the military

data for any circuit, but Seelbach wants integrated. People have de-

says, "If it weren't where it should signed a lot of equipment with

be, he wouldn't be announcing the military-specification parts in dis-

product."

crete form," explains Lehner, "and

The Phoenix division holds the now the military says integrate, so

basic patents on emitter-coupled the equipment maker goes the hy-

logic, and Seelbach says the soon- brid route and has aprimary posi-

to-be-introduced third generation is tion as abidder." Some of the more

logically compatible with mcci., 1 popular npn silicon transistors Leh-

and 2 families without any inter- ner cited in this category are the

face circuitry. Prices have not yet 2N2217, 2N2218, and 2N2219, all of

been established.

which are covered by Motorola's

unencapsulated line. The pnp

counterparts are the MSC2907A

Going naked

and 2906 switching and amplifier transistors. Motorola substitutes

A number of semiconductor mak- the prefix MSC for the 2N prefix.

ers have been selling unpackaged

Other devices in the line are npn

chips--both discrete devices and and pnp low-level amplifiers

integrated circuits--for quite afew (MSC2484 and 3251, respectively);

years, but until recently most of npn and pnp high-voltage switch-

them haven't been advertising the ing and amplifier transistors

bare chips.

(MSC3501 and 3637); npn and

Several factors have contributed pnp radio-frequency amplifiers

to this reluctance, especially on the (MSC918 and 4957); npn and pnp

part of the bigger vendors: the core drivers (MSC3725 and 3467);

market is small (estimated at $25 and npn and pnp low-level

million a year); small orders are switches (NISC2369 and 3546).

typical, and vendors have felt they

Joining the fun. Lehner says

would be giving away some of that Texas Instruments Inc. and

their secrets if they made aregular the Raytheon Co. have been sell-

business of selling unencapsulated ing standard unpackaged chips for

dice.

at least ayear, and it's known that

That reluctance appears to be on Fairchild's Semiconductor divi-

the wane, principally because the sion, the National Semiconductor

market is mushrooming rapidly as Corp. and the Signetics Corp. are

hybrid-circuit suppliers step up also in the business. But none of

their demand for chips they pack- the others appears to be pursuing

age later. The larger semiconduc- the market with as much gusto as

tor manufacturers are reassessing Motorola. Lehner notes that stand-

their positions, and one--the Semi- ard zener diode chips will be com-

conductor Products division of Mo- ing next from Motorola, to be

torola Inc.--plans to introduce a followed by unencapsulated

line of standard unpackaged sili-

Meanwhile, a new firm, Intersil

con transistors as its first aggres- Inc. of Cupertino, Calif., will begin

sive move to get abigger share of selling as its first product a com-

the business [Electronics, April 1, plete line of unpackaged flip-chip

p. 26].

transistors and n-channel junction

Military orders. The devices field-effect transistors.

chosen-14 in all--are Motorola's

National's marketing manager,

most popular npn and pnp discrete Donald Valentine, says, "We've

transistors. One of the prime rea- just been quietly selling afew dice.

sons for Motorola's move, says Leo We never imagined anyone noticed

Lehner, manager of product mar- us--much less Motorola." He says

the firm sells 15 of its prime lc's and about 25 discrete transistors in chip form, and has been stocking dealers for the past six months.
Signetics has been selling unpackaged lc chips for three years, and officials there report no reluctance to do so, but neither is there any intention to introduce off-theshelf dice.
Lehner says the military systems in which the chips are ultimately used, such as missile and guidance systems and airborne computers, involve fairly complicated technology. As aresult, Motorola can get 75% to 80% of the price it asks for the same device in a metal can. "The idea of the game is not economy at all," he says. "The hybrid or multichip circuit supplier wants these chips for size reasons, technology, and to win bids."
"If he wants to make a100-volt lc, or afancy r-f mixer, he can't do it with a monolithic lc, so he has to go the multichip route."
Microselling. Lehner expects most of Motorola's chip sales to be in quantities of thousands, but the division isn't overlooking smaller orders. Chips in the standard transistor line will be shipped in containers for as few as 10 dice; another carrier accommodates 1,000. In both, the passivated dice fit in individual recessed compartments. A glass lid slides flush over the "bins," preventing movement of the chips in shipping and allowing the buyer to see them without opening the compartment.
Ronald Camp, Motorola product planner for silicon transistors, says buyer sophistication has done alot to break down Motorola's earlier reluctance to sell chips. "We had to go through alearning cycle with the customer on testing, bonding, and application. Maybe he didn't know how to bond well and he'd blame us for supplying abad chip. Now the customer is generally more knowledgeable in all these areas."
Wafers from which the chips are taken are tested only to the minimum specification for adevice, but Camp points out that there will be almost no differences in the maximum ratings of the devices as chips
or in packages.

Electronics April 15, 1968

47

Electronics Review

Instrumentation
Lighting own way
Ever since the introduction of coldcathode indicating tubes, instrument makers have been designing them into their products. But the Monsanto Co., whose electronic instruments group is arelative newcomer, has now decided to follow an independent line: adaptation of its own research on solid state displays. The company believes it has struck pay dirt with a light-emitting diode array. The array is used as the numerical readout in an experimental counter! timer.
Fred Katzman, who heads the instruments group, says the array represents the first time the feasibility of a solid state readout has been demonstrated as an integral

part of adigital test-and-measuring instrument.
Boon. The advantages are con-
siderable. Since each element in the array lights when it is forward biased with a current of about 10 to 100 milliamperes at about 1.5 volts, the displays are compatible with integrated circuits. Conventional displays, using cold-cathode indicators, aren't compatible be-
cause the tubes require about 100 volts. What's more, the displays can be driven directly from adual in-line lc, while tube displays need aseparate power supply and driver for each digit.
Not only are drivers, high-voltage supply, and tubes eliminated, but, says George M. MacLeod, director of the Monsanto Electronic Special Products division, "the solid
state displays have longer life, greater strength, less heat genera-

tion, no parallax, and faster switching time." He claims the array eliminates the radio-frequency interference traditionally associated with gas-discharge tubes.
Each light-emitting diode array
can combine numbers, letters, and symbols.
Says MacLeod: "No cold-cathode tube or similar readout could provide the full alphabet because there just isn't enough depth to in-
clude 26 letters." Proof of the pudding. Monsanto
modified one of its general-purpose counter/timers with the diodes. The conventional five-digit coldcathode display was replaced with a red numeric display of gallium-
arsenide phosphide diodes. The diodes had proved reliable
after several years of use singly as indicator lights on other Monsanto products. Even though the array's light output of 115 foot-lamberts is significantly less than a coldcathode tube's 200 foot-lamberts, it is sufficient under ordinary operating conditions. Moreover, the diode array offers superior contrast.
There still is abarrier: the cost
now is about $165 per digit. However, Monsanto believes that refined production techniques will make the cost competitive with conventional displays, which cost between $20 and $70 per digit.

Replacement. Monsanto developed this counter/timer to prove the feasibility of asolid state display in an instrument. The light-emitting diode array eliminates power supply, drivers, and tubes of conventional cold-cathode readout displays. The electronics that have been eliminated are outlined in the photo above.
48

In phase
The growing sophistication of radio transmission has generated a corresponding need for quartz crystals that can give very precise frequency separation. That need, in turn, is producing a new generation of highly accurate instruments to test and measure crystal capabilities.
Conferees at the Army Electronics Command's 22nd annual Frequency Control Symposium will get a liberal helping of such devices to go with their salt water taffy when they gather in Atlantic City, N.J., next week. The Army itself has come up with one of these instruments, the Western Electric Co. another, and the Hewlett-Packard Co. has computerized
Electronics !April 15, 1968

Boost IC op amp

power with

Helipot's miniature

hybrid

amplifier.

re.ecic man lei ,

HELIPOT DIV 821

Actual Size

Here's how it performs:
·2.5 watt output ·30 MHz bandwidth ·:±16V voltage swing ·less than 90 0 phase shift ·--55 to +125°C operation ·foldback short circuit immunity ·protects op amp and power
supply from overload reflections

atypical hookup:

The new Model 821 is ahybrid, cermet thick film power amplifier which drives .oad resistances as small as 100 ohms to within 4volts of the supply voltage from d-c to 30 MHz. Its combination of unity voltage gain and wide bandwidth permits boosting the power of an IC amplifier without affecting its other performance capabilities. In addition, the Model 821's ability to block all overload reflections results in the prevention of heat generated errors in the op amp and allows immediate recovery upon overload removal. Completely self-contained, this fully sealed power amplifier is only 0.170" high, occupies just 0.5 sq. inches of board space, and is compatible with both flat pack and dual in-line IC packages. Ask your local Helipot sales representative for complete information on the Model 821.
Beckman°
INSTRUIVIENTS. INC. HELIPOT DIVISION
FULLERTON, CALIFORNIA ·92634
INTERNATIONAL SIASID:ARIES: GrNtVA, MUNICH; GA, ..,01,1,:S. SCOTLAND; TOKYO; PARIS; ·A, CTOWN: LoNrcci; mrxCO OCT

Here's the price:
$35.00-1 to 9 quantity. Delivered from stock

Electronics April 15, 1968

Circle 49 on -eader service card

49

Electronics Review

the whole shooting match. In-house. The Army's develop-
ment was spurred by increasing military use of suppressed-carrier single-sideband transmission, a mode that requires precise crystals in the lower reaches of the high-
frequency range. The instrument, a highly developed, well-buffered oscillator, bases its correction signal on phase-shift information
rather than less accurate frequency data.
The device is extremely sensitive because it works passively: it
measures a crystal tickled with only 0.1 -- '5 watt and can be used with most commercially available
bridges. What's more, it can measure a 100-megahertz crystal to
within 0.1 hertz and is self-checking. Made under license by Parzen Research Inc. of Westbury, N.Y., the tester will be described at the symposium by O.P. Layden, A.D. Ballato, and C.L. Shibla of the Army's Electronics Command.
Familiar ring. A similar tech-
nique has been used by Western Electric's North Andover, Mass., laboratories. The method developed there by Robert P. Grenier sends a synthesizer's signal through the crystal into a calibrated phase detector. That frequency passing through the crystal with the least phase shift is the resonant frequency. By locking the synthesizer to that frequency and displaying it on an oscilloscope, the crystal's resonant point can be determined.
This technique, Grenier believes, will cut resonance uncertainty from about four parts in amillion to one part in 10 million. The technique may go on the production line later this year, he adds.
Automated. The Hewlett-Packard innovation, from its labs' piezoelectric department, could bring a new look to the IEEE'S specs for crystal testing, drawn up in 1957. H-P's new method, according to C.A. Adams, co-author of apaper
on it with D.L. Hammond and Albert Benjaminson, uses the IEEE pi
network with avector voltmeter to make phase measurements instead of the traditional amplitude measurement. From those measure-

ments, frequency and impedance are derived.
"When the crystal is in perfect resonance," explains Adams, "the phase goes to zero. The voltage ratio in the pi network gives you the voltage amplitude ratio. When you take a small computer and hook it up to the vector voltmeter you simply program what you want to look at in the frequency range--the impedance or resonance spectrum, for example."
With a knowledge of these parameters all equivalent circuit parameters (Li, Ri, G, and Co as stated by the IEEE) can be computed, Adams says.
Medical electronics
Eliminating the paper work For every heart disorder acardiologist uncovers with his electrocardiogram machine, he must scrutinize yards of the EKG'S paper tape, searching for abnormalities in the tell-tale wiggly lines. The slow process suffices when the doctor has but one patient to examine. But with doctors now pressing for mass

screenings to uncover heart troubles early, the tape-monitoring task
could become Herculean. The Humetrics division of the Thiokol Chemical Corp. has now developed an EKG machine whose signals can
be interpreted by a technician. It signals only when it locates something wrong. If it finds so much as
ahint of an abnormality, the patient is referred to acardiologist.
The unit--called an Electrocardioanalyzer (EcA )--is similar in function to two other machines, which monitor heart sounds rather than the EKG signal. One, the Cardioscan, is from Humetrics also and was designed for children [Electronics, Dec. 13, 1965, p. 38], and the other, for adults, was developed by Tokyo
Shibaura Electric Co. (Toshiba) of Japan [Electronics, Jan. 9, 1967, p. 252].
Mass action. The new Humetrics device takes about aminute to complete the test and Humetrics officials believe more than 50 persons an hour can be monitored.
The instrument not only differentiates between normal and abnormal EKG patterns but also pinpoints the abnormal parameters. Electrocardiographic signals from the patient are picked up by electrodes attached to the arms, legs, and chest.

Quick check. Mass screening for beFrt defects can be performed by this EKG machine, which reports only an abnormal signal.

50

Electronics ;April 15, 1968

DON'T THINK IN TERMS OF GATES WHEN YOU DESIGN ENCODING OR DECODING CIRCUITRY.

--A-

3-811 BINARY GENERATOR

-8 --

THINK DIODE MATRICES.
Now you can encode...decode...or time-share both functions... inexpensively, efficiently, easily, and without fear of cross-coupling. Use Radiation dielectrically isolated diode matrix integrated circuitry. Readily available in dual in-line and TO-84 flatpack configurations.
Suppose you need a three-bit binary output encoded into a four-bit binary shift code. Why use five AND gates and four OR gates? Simply combine these nine gate functions into one RM-30 six by eight diode matrix and save both time and money.

BINARY --3' -- COUNTER --27--,
-- 27

DECIMAL DISPI AT

Why use ten logic gate packages to decode from binary to decimal for display read-out? Use only two RM-84 eight by five diode matrices. It makes no difference what weighted binary code you are working with. Radiation diode matrices can be easily customized to match.

9's COMPLEMENT
CODE GENERATOR

1 4-2 4-- 1

0 11 3 4 5 6 78 9

8·4·2·1 BCD

When one logic code must be converted to several other codes for processing, think diode matrices! Specify only four RM-84 diode matrices and form a 16 by 10 matrix array. Sxconversions can be performed by this single bi-directional array...replacing approximately 80 logic elements.

You never have to think in terms of gates again. Think Radiation diode matrices!
Radiation stocks acomplete line of dielectrically isolated diode matrices, easily customized to your particular encode-decode needs. These can be combined with Radiation interface circuits to provide the most economical, convenient and reliable diode logic available today.
Contact your nearest Radiation sales office to find out how inexpensive diode matrix integrated circuitry really is. You'll be surprised how fast we can deliver, too.

»me RADIATION I C" OR PG R AT E
SUBSIDIARY OF HARRIS-INTERTYPE COR PORATION MICROELECTRONICS Divisuoiv

Electronics April 15, 1968

Sales Offices 600 Old Country Road. Garden City. N Y 11530 (516) 747-3730 -- 2600 Vorginla Avenue, NW. Washington. D C
20037. (202)337-4914 -- 6151W Century Boulevard. Los Angeles. Cal., 90245, (213)670-5432 -- P.O Box 37, Melbourne. Florida 32901. (305) 727-5430 -- International Sales Marketing Department P 0 Box 37. Melbourne. Floreda 32901. (305) 727-5430

Circle 51 on reader service card

51

Electronics Review

KEPCO
MULTI RATED
POWER MODULES

Typical Uncased Module
Kepco's new "PAR" Power Supply modules are available in voltages from 4 volts to 60 volts, adjustable -±-5% about the nominal. Two current ratings apply for each module, one for temperatures to 65 °C and a higher rating for the usual industrial environment of 40 °C. Regulation, line: 0.005%, load: 0.01%, temperature coefficient 0.01% per °C, ripple 0.25 mV rms - modules may be controlled from 0 to their nominal band with linear current derating. Size 63/4" x 43/4" x 103/8"- rack mounts available too.

MODEL
PAR-4 PAR-7 PAR-12 PAR-15 PAR -24 PAR-28 PAR-36 PAR-48 PAR-60

OUTPUT
VOLTS
4±5% 7:1- Ws 12 ±5% 15±5°/o 24±5e/o 28 ±P/o 36±5°/o 48± 5% 60 ±5%

OUTPUT CURRENT

at ambient temp
65 cf 40 0r

PRICE

55 CTT

30 CT,

0-9.0 0-11.0 $195.00

0-8.0 0-10.0 195.00

0-5.5 0-7.0

195.00

0-4.6 0-6.0

195.00

0-3.4 0-4.0

195.00

0-3.1 0-3.7

195.00

0-2.3 0-2.8

195.00

0-1.8 0-2.3

195.00

0-1.5 0-2.0

195.00

TUncased: TI Cased

For Kepco's brand new Catalog B-678 containing complete specifications and extensive applications notes. write Dept. R-14
" ------------

(seer/CC0-2) -------------

131 -38 SANFORD AVE. ·FLUSHING, N.Y. 11352
·(212)461-7000 ·TWX #710-582-2631 ·

52

Circle 52 on reader service card

Lee Baessler, Humetrics director of

Growing bananas. Heart of the

engineering, says this system presents astandard lead input to the analysis circuitry. In EKG recordings,

achievement was the successful growth of asingle crystal of barium sodium niobate (Ba2NaNb5013),

13 leads are used to make various humorously called bananas by the

physiological measurements [Elec- developers. This crystal is not dam-

tronics, July 10, 1967, P. 105]. In aged by laser light as other mate-

the ECA unit, afive-lead configura- rials have been, and its ability to

tion using electrodes has been de- generate harmonics is far superior

veloped. These leads measure such to anything so far developed.

parameters as P amplitude, P po-

Up to now the best continuous

larity, P width, PR interval, Q am- tuning-achieved using electro-optic

plitude, Q width, R amplitude, S techniques-has only covered a

amplitude, and others [Electronics, bandwidth of -±45 Ghz [Electron-

July 10, 1967, p. 104] to determine ics, Nov. 13, 1967, p. 58]. Paramet-

if they are within acceptable limits. ric oscillators using other crystals

To make certain the EKG signal is such as lithium niobate could only

not giving false information, Hume- tune pulsed light beams.

tries incorporated special circuitry

Efficiency of the new parametric

to prevent analysis when excessive oscillator is about 1% though the

baseline drift or 60-cycle interfer- developers are confident of increas-

ence exists. Abnormally high or low ing efficiencies to at least 10% and

heart rates also prevent correct anal- perhaps 20%. What remains now is

ysis and an auxiliary display alerts to improve stabilization techniques.

the operator to this condition.

Selecting mirrors. In the Bell

In the cards. The instrument is Laboratories set-up, a bananas

contained in a 17-by-11 1/2-by-71/8- crystal, placed in the cavity of an

inch case weighing 28 pounds. All yttrium aluminum garnet (YAC)

circuitry is contained on four laser, doubles the 1.06-micron out-

printed cards incorporating Signet- put frequency, providing the 0.53

ICS micrologic and Philbrick opera- micron pump frequency. The green

tional amplifier components.

beam then is focused by alens and

At $9,300 per instrument, Hu- directed at atemperature-controlled

mertics officials foresee large use bananas crystal. Inside the crystal

of the ECA by industrial concerns, it interacts with the internal elec-

health institutions, schools, offices, trical fields and produces two co-

and professional and amateur athletic teams.

herent waves, the sum of whose frequencies equals its own fre-

quency.

Although no attempt was made to

suppress one of the output frequen-

cies, this could be done easily by

Advanced technology

choosing the proper mirrors that, along with the second bananas

crystal, form the parametric oscil-

Pick acolor

lator cavity. For parametric oscillation to oc-

Tuning a coherent light oscillator cur, the pump and two harmonic

continuously through the visible frequencies must move in synchro-

light spectrum down through the nization through the crystal. That

infrared has finally become pos- condition can only be met in anon-

sible. A team at Bell Telephone linear optic crystal, where the index

Laboratories has built acontinuous of refraction varies with crystal

parametric optical oscillator that temperature and with the frequency

converts green light (0.53 microns) (dispersion) and polarization (bi-

over a wavelength range covering refringence) of the light. In the ba-

0.98 to 1.16 microns. The same os- nanas crystal there's atemperature

cillator can cover an even wider at which dispersion and birefring-

band of frequencies-30,000 giga- ence offset each other for a par-

hertz-extending from 0.4 to 4mi- ticular pump and pair of generated

crons (violet to far i-r).

frequencies so that all three are in

Circle 53 on reader service card->-

EH LEADS
THE PULSER
REVOLUTION

Name wl-a1 you want in your next pulser

the E-H 139B

has it. Broad oqerating -ange (the first pulser with a 1CHz

to 50MHz rep rat9.)±3C MV to 10 V output. Pulse widtr and

delay variable &Dan 10 ns to 10 ms. Plus a unique baselire off-

set featire whicr allows -he pu'se train to be adjusted of zero Lp to 2volts in eiiler

Chances are, 1his versatile pilser can do the work of three or four

pulsers you are ncw usho for IC or logic testing applicatiqns. Let

us slow you hew.

E-H RESEARCH LABORATORIES, INC.
163 Adeline S-reet · Canard, Zaieorria 94607 · (415) 834-3030 · TWX 910-366-7258 In Europe: E-l- Re5earch talwrato -ies ·Fled) N.V., Box 1018, Eindhoven, The Netherlaids, Telex 51116 hi Japan leratsu Electric Co. Ltd., No. 710, 2-Chome KJgayama Suginami-Ku, Tokyo .:apart

Electronics Review

"fine line" etcher
for prototypes--limited runs

Model No. 201 (illus.), 11' x 14" one-sided
boards or one 11"x 14" two-sided board:

$etc7hes9t5wo
Pat, applied for

ETCH YOUR OWN PCBOARDS
AUTOMATICALLY
(in less than 5minutes)

from this --> to 11" x14"
Shown Actual Size

· No cooling or venting required! · Etches as fine as .0011 · Cuts costs in half--saves time! · Complete photo processing instructions! · Work is illuminated while etching! · No patterning ... minimum undercutting!

NOW IN USE BY:

AMP, Inc. Ampex Corp.
Atomic Energy Corn. Bendix Charles Bruning
Esso Research General Dynamics General Electric IBM ITT Lear Siegler Magnavox Micro Switch NASA
Owens-Illinois

Sprague Electric Union Carbide U.S. Air Force Western Electric Whirlpool M.I.T.
Oklahoma State U. Purdue Univ. Washington Univ. Univ. of Calif. Univ. of Chicago Univ. of Colorado Univ. of Georgia Univ. of Hawaii Univ. of Penn.

CYCLO-TRONICS, INC.
3858 N. CICERO -- CHICAGO, ILL. 60641 TELEPHONE: (312)-282-6141

54

Circle 54 on reader service card

step. Then the pump gives up its

Long shot. The CO2laser is suit-

energy to the harmonics, which able for such long-haul transmis-

grow into coherent waves.

sion, says Goodwin. Carbon-dioxide

The members of the develop- designs have the highest power po-

ment team are Joseph E. Geusic, tential of existing lasers--outputs

Hyman J. Levinstein, Jerry Rubin, up to several thousand watts have

Shobha Singh, R.G. Smith, and already been reported. And the la-

Le Grand Van Uitert.

ser's wavelength, 10.6 microns (far

infrared), is relatively immune to

atmospheric attenuation. During a

hazy day, attenuation of avisible

Communications

beam might reach 100 db; but for the 10.6-microns laser, it's only

about 15 to 20 db between the lab

Taming the CO laser

and Baldwin Hills, he says. In addition, the efficiency of CO2

The use of lasers to beam television lasers is much greater (10% to

signals over short distances is a 15%) than that of lasers in the visi-

relatively easy stunt performed at ble spectrum (less than 0.1% for

several labs. But training the beam an argon ion laser, for example).

at atarget millions of miles away Finally, Goodwin says the far in-

is something else again. Stability frared is of interest because atmos-

problems with the laser and atten- pheric turbulence, which disturbs

uation of the beam by the atmos- the coherence of visible light, does

phere play havoc with the signal. not significantly degrade coherence

Researchers at the Hughes Aircraft at 10.6 microns.

Co. have taken asignificant, albeit Goodwin believes existing lasers

small, step (18 miles) in that direc- could handle the transmission of a

tion.

real-time tv signal from Mars using

The team at the firm's Malibu, no more than 100 watts of power.

Calif., labs have built a carbon-

Taking pains. The researchers

dioxide laser system that beams a went to great lengths to stabilize

tv signal the 18 miles between the the output frequency, isolating the

lab and Baldwin Hills. The received laser acoustically by suspending it

signals, using optical heterodyning in aspring system and hermetically

techniques, are good enough to sealing it. This eliminated vibration

meet industry standards for com- from the floor or turbulence from

mercial transmission, says Frank air currents.

Goodwin, head of the research team The Hughes system consists of

and asenior member of the techni- two identical lasers--the transmit-

cal staff. The signal-to-noise ratio ter oscillator at Baldwin Hills and

has been measured at 60 decibals the receiver local oscillator at Mal-

in the f-m mode.

ibu. The video input to the trans-

Over the air. Hughes designed this laser system for transmitting tv signals over an 18-mile link. The next step? Maybe Mars.
Electronics April 15, 1968

Low operating currents... ultra low leakage

Take a close lock at the lower scope trace. The sharp knee comes from low field emmission leakage all the way out to breakdown, and extremely tight regulation at low current levels after breakdown.
No other zener can approach the LVA performance below 10
Electronics IApril 15, 1968

volts. You get low operating currents plus ultra low leakage ir a single device.
The Low Voltage Avalanche zener is available in 10 values from 4.3 volts to 10 volts. Delivery is off-the-shelf from authorized TRW distributors, or conl:act TRW Semiconductors, 14520 Aviation

Lawndale, Ca if. 90260. Phone (213) 679-4561. TWX 910325-6206. TRW Semiccnductors is a subsidiary of TRW INC.
TRW

Circle 55 on reader service cari

55

Mlodel 1100 Semiconductor
Test System

à. ·

·· · e
o ·* ......

··

· e

' e bb* 6 ··

New automatic systemn
offers high current transistor and diode
testing capabilities at minimum cost!
The new Test Equipment Corporation Model 1100 test system gives the budgetconscious user more testing capability per dollar than any available system. It features 100 amp pulse gain measurements, 1 kilovolt breakdown voltage capability and reverse leakage current measurements to 100 picoamps.
In addition, the Model 1100 automatically sequences through five tests and logs resulting data on paper tape. Out-of-limit measurements are printed in red. This versatile system may be expanded to include either a Tally 420PR-24 punched tape or IBM 526 card punch.
Write today for technical and pricing information.
TEC offers test system design and engineering capabilities and on request will quote systems to meet specific user requirements.
Test Equipment
CORPORATION
P.O. BOX 20215, DALLAS, TEXAS 75220 ·214/357-6271

56

Circle 56 on reader service card

Electronics Review

mitter cornes from either avidicon camera or a commercial tv set. It is sent through amodulator driver before entering the electro-optical modulator housed inside the transmitter oscillator cavity. This modulator is a gallium arsenide crystal
5 centimeters long with its end faces polished and coated with an
antireflection material. Goodwin says frequency modu-
lation in the laser is produced when the phase of the light is modulated.
"We achieve f-m by driving the
modulator inside the laser oscillator itself," Goodwin notes.
The technique has its drawbacks, however. Putting the gallium arsenide crystal inside cuts output
power from a typical 10 watts, to about 1or 2watts. Hughes is already working on awideband modulator outside the cavity that might support many tv channels; the present system is limited to one. By then, the researchers plan to transmit digitally, but they will continue to use hetrodyning because of the tremendous sensitivity it provides.
The modulated signal is fed to transmitter optics, across the 18mile span to Malibu, and into the receiver optical system. Both the transmitter and receiver optics are 3-inch-diameter off-axis parabolic reflecting telescopes.
Cold storage. Receiver optics focus the beam down onto the mercury-doped germanium detector, which is housed in a dewar and kept at 21°K with liquid nitrogen. This is where heterodyne mixing takes place. A beam provided by the laser local oscillator is superimposed on the detector and added to the incoming signal.
The i-f amplifier, with a center frequency of 30 megahertz, and an 8-Mhz bandwidth, follows the detector. From the amplifier, the signal is fed to a discriminator, to which is attached atelevision monitor to display the received image. Part of the discriminator output drives an automatic frequency controller. This locks the receiver local oscillator 30 Mhz away from the frequency of the transmitter laser, which is 2.8 X 1013 hertz. Goodwin says the frequency changes only about 3 parts in 2.8 million. The

entire system represents an investment of about $20,000 in hardware.
Consumer electronics
Radiating worry
Concern over radiation from consumer and industrial products is spreading out in almost as many directions as the radiation itself. But color television sets, which started the whole thing, arc still the source of most of the worry.
The latest reactions to these waves of apprehension include the following:
·The cloak of anonymity has been lifted from the color tv sets tested for radiation leakage earlier this year.
·Industry and Government are taking the first steps toward adoption of common standards for detecting and measuring radiation.
·The radiation protection bill passed by the House and atougher Administration-sponsored bill will get hearings next month by the Senate Commerce and Labor Committee.
·The National Association of Government Employees is starting to question limits set for air traffic controllers who watch radar scopes.
·Studies of potential laser damage are being extended after an initial survey showed that about 10,000 workers may be exposed to dangerous laser beams.
Naming names. The National Center for Radiological Health, after alittle prodding, disclosed the brand names of the 1,124 sets tested and how they scored. The initial report didn't mention any company names; the center said that to do so could be misleading, because the survey covered only sets owned by Public Health Service employees in the Washington area. Only after the press demanded the brand names under the recently enacted Freedom of Information Law did the center open up the books. The survey showed that 6% of the sets produced excessive radiation. The test results

Electronics IApril 15, 1968

( ) ) S /T/20Af Series
150 C-B

Silicon Controlled Rectifiers

235 Amperes RMS 25 to 1200::: PRV

FORWARD CONDUCTING

It avy, --AVERAGE FORWARD CURVEN7

Vtm

--MAXIMUM PEAK FORWARD Ntil. ,,(L 500 A. PEAK 180 CONDUCTION ANGLE

lh

--TYPICAL HOLDING CURRENT AT 25 C.

Its::: --MAXIMUM PEAK ONE CYCLE SURGE CURRENT

It

--Pt FOR FUSING FOR TIMES

1.5 MILLISECONDS

Idol --MAXIMUM FORWARD LEAKAGE CURRENT AT 125 C. AND EB

tell --MAXIMUM OFF TIME AT 125 -C.

ton --TYPICAL ON TIME

tr --TYFICAL RISE TIME

t d

--TYPICAL DELAY TIME

ATj

-- OMPAEXRIAMTUIMNG THJEUNRCMTAILONRESTIESMTPAENRCAET,URJEUNCTION TO CASE OC

Tstrg - STORAGE TEMPERATURE

BLOCKING

Irm (tv/dt

MAXIMUM REVERSE LEAKA3E CURRENT AT 125 C. AND PRV. ..
MINIMUM CRITICAL EXPOP, ENTIAL RATE OF RISE OF FORWARD BLOCKING VOLTAGE

TRIGGERING

Vgt

--MAXIMUM GATE VOLTAGE TO TRIGGER AT 25 C.

Vgt

--TYPICAL GATE VOLTAGE 7) TRIGGER AT 25 -C.

Vgt

--TYPICAL GATE VOLTAGE 7) TRIGGER AT 125 C.

1p,t

--- MAXIMUM GATE CURRENT TO TRIGGER AT 25 -C.

Igt

--TfPICAL GATE CURRENT TO TRIGGER AT 25 C

Pgm --MAXIMUM PEAK GATE POWER

Pg avg --AVERAGE GATE POWER

Igm --MAXIMUM PEAK GATE CURRENT

Vgm --MAXIMUM PEAK GATE VOLTACE (FORWARD

MAXIMUM PEAK GATE VOLIA7E ÇREVERSE

10 5 3 7 .

er '

01225 CC, W

11
2 5 V. 1 3 V. 0 9 V. 200 MA 100 MA 10.0 W. 2 0 W. 2.0 A. 10 ^ " 5

*1300 Volt Transient Rating

/Inc SYNTRON A DIVISION OF FMC CORPORATION CORPORA, ON c> 241 Lexington Ave.
Homer City, Pa. 15748 Telephone 412-479-8011
Electronics 'April 15, 1968

Name/Title Company Street City/State...

Please send information on:

El Series 150 C-8 Silicon Controlled Rectifiers

El Silicon Rectifiers

Selenium Rectifiers

fl Selenium Surge

Zip

Suppressors

68R2

Circle 57 on reader service card

57

Electronics Review

Last Tuesday morning
alot of people on Pleasant Avenue were glum.
But not "Smiling" Sam Price. He's Dne of the Twelve Cranks on Pleasant Avenue. And last Tuesday he found a lousy connection in aTrygon Liberator Power Supply that was coming off the line! It made his day!
The point is, of course, that lousedzip Liberators never leave Trygon. Not with Sam Price and his un-merry men around. Their job is finding problems for us; so you don't get any problems from us.
Sam's pet, the Liberator, gives you the ultimate in IC and transistor system power in minimum size at lowest possible cost. Wide slot adjustment ranges with voltages up to 160v. Output current levels up to 40 Amp (3 1/ 2 ") and 70 Amp (51/ 4 "). .005% regulation/.5 mv ripple/ 3mv P-P noise/.01% stability/ extremely low output impedance/ MIL Spec. performance /integral slide mounting! automatic load share paralleling/ overvoltage protection.
And you can be sure of this. Every Trygon Liberator Power Supply comes off the line under Sam's baleful eye. Order one and see.
riiire Att 11,e. e

Trygon Power Supplies
Ill Pleasant Avenue, Roosevelt, LI., N.Y. 11575 Trygon GmbH 8Munchen 60. Haidelweg 20, Germany

58

Circle 58 on reader service card

are shown at the right. The test revealed some extremely
high radiation leakage. Of the 66 sets leaking radiation above the
accepted safe level of 0.5 milfiroentgens per hours (mr/hr), 38 sets registered above 1.0 rnr/hr, and three
others actually hit 12.5 mr/hr--the maximum reading on the test instrument. Center engineers believe the actual readings on these sets were much higher. The three hot sets were a Setchell-Carlson, Zenith, and aMagnavox. The Magnavox had an RCA shunt regulator tube and a Sylvania picture tube and was operating at excessively high voltage.
Twenty-three sets gave readings of between 1.0 and 2.0, five between 2.0 and 3.75, ten between 3.75 and 12.5, and three over 12.5.
The survey said the probable primary sources of X-radiation emissions were the high-voltage shunt regulator tube, the high-voltage rectifier tube, and the picture tube. However, in two sets, no specific source could be identified.
Do it yourself. James G. Terrill, the director of the center, said the Washington survey included too few sets to yield an accurate nationwide estimate. He estimated, however, that 700,000 to 1.4 million color tv sets in the U.S. leak excessive radiation.
But instead of starting anationwide campaign to halt the leakage, the center is working with manufacturers to make certain that all new sets are tested before leaving the factory. Because of the shortage of trained technicians who are properly equipped with devices to detect and measure radiation, the center is only recommending that owners take their sets to a repair shop to make sure the high voltage is set at the proper level. This usually reduces the radiation.
The survey found that four brands--RCA, Zenith, Magnavox, and Setchell-Carlson--made up 86% of the number of sets leaking excessive radiation. There were no General Electric sets that leaked excessive amounts, obviously because GE tracked down and adjusted its faulty receivers after they set off the big scare last year.

X-ray emission from color tv

Total sets

Brand name surveyed

RCA

360

Zenith

162

Sylvania

100

Motorola

75

GE

72

Sears

71

Magnavox

69

Philco

45

Airline

33

Admiral

30

Westinghouse

19

Heath

18

Dumont

16

Penncrest

15

Setchell Carlson

13

Packard Bell

7

Muntz

6

Curtis Mathis

4

Delmonico

2

Symphonic

2

Bradford

2

Clairtone

1

AMC

1

Panasonic

1

Total

1,124

Sets above safety standards
20 19
0 1 10 0 1 0 0 0 0 1 8
o o o 1 1 o o o
66

Manufacturers of brand named sets

Sears

Warwick Electric, Toshiba

Airline

Hoffman Products, Hayakawa,

Magnavox, Wells-Gardner, Hoff-

man Electronics

Penncrest Wells-Gardner, Matsushita, West-

inghouse, Clairtone

Muntz

TV Corp. of America

Bradford Wells-Gardner, Matsushita

Clairtone Westinghouse, Wells-Gardner,

RCA

AMC

Clairtone

Panasonic Matshushita

At the same time the center was preparing to disclose the manufacturers' names, it was sponsoring aconference in Washington on detecting and measuring X-radiation from color tv receivers. Up to now, there have been no uniform methods of detecting or measuring it. Although there are no definite plans yet, the center and the Electronic Industries Association will probably organize a committee to work out recommendations.
Question of control. Although industrial trade unions made some noises about worker protection after the GE reports, one of the first unions seriously looking into the matter is the National Association of Government Employees, which represents air traffic controllers.
Alan J. Whitney, executive vice president of the union, in testimony before Congressional committees, has implied that the Federal Avia-
tion Administration's radiation

Circle 59 on reader service card-->-

NEW SOLID STATE VOLT-OHMMETER

1. 2. 3.

F--T CIRCUITRY --PORTABLE BAT -- ERY OPEUTED WITH 11 MEGO -IM INPUT 11111PEDANCE (FIELD EFFECT TRIANSISTOR). STABLE: LOK DFIFT.
ONE SELECTOR SWITCF YIINIMIZES CHANCE OF NCORRECT SETTINGS AND BURNOUTS. D: POLARITY REVERSII·G.
HUMAN ENGINEERED POR EASE OF USE. cum' UNCLUTTERED SCALE, EXCELLENT
RIGE OVERLAP, FOR MORE ACCURATE READINGS.

· Model 600 TVO
S2 ransstorized Volt-Ohmme:er) .

Model 600 on stand har dle leather case 114 70

Suggested U.S.A. User %Ice Available Now At Your Local Distributor

ELECTRIZAL INSTRUMENT COMPANY BLUFFTON, CHIO

Electronics Review

LESS THAN 18 PER CIRCUIT

safeguards are inadequate. The
FAA'S "maximum exposure" to ion-
izing radiation is 100 milliroentgens aweek. Based on a40-hour week, this equals 2.5 mr/hr. The generally accepted safe level, as noted, is 0.5 mr/hr.
Hard light. In another area, a
survey made by the Public Health Service's National Center for Urban and Industrial Health in Cin-
cinnati disclosed that 60% of laser workers in the scientific instrument industry faced potential risk of eye (lainage or serious burns. The figure was based on a study on the
use of 267 lasers in 43 plants in Massachusetts. The survey is now being extended to New Jersey and later will move to California.
The survey called laser safety re-
quirements surprisingly lax. For example, only about 45% of the firms required eye shielding in laser areas, and about 25% of the goggles provided are inadequate. Only afew plants had laser warning signals or signs. At the same time that this report was released, the newly formed laser subdivision of the FIA voiced approval of the radiation
control bill passed by the House, which covers lasers, and organized acommittee to work on laser safety studies and promotion.

Military electronics
Back to the drawing board
Less than a month after Robert S. McNamara closed the door on his Pentagon office for the last time, his successor slammed the door on one of the former Defense Secretary's most cherished dreams --a military aircraft that would be almost everything to almost everyone.
McNamara had nursed the controversial craft--originally designated the TFx--through several modifications and had staked his reputation as a managerial genius on its success.
But the bubble burst late last month when one of the plane's prime missions was dropped. Defense Secretary Clark Clifford decided that the brass had been right all along: the Navy version, the F-111B, was, among other things, too heavy to be effectively flown from a carrier deck.
And just a few hours after the Defense Department's decision, the Senate Armed Services Committee axed the fiscal 1969 funds earmarked for the production of 30 F-111B's. The Congressmen in-

The new Daven "X" switch has been life tested for 50,000 cycles of rotational life with no failure carrying a .500 amp load at 125°C.
The 10 deck, 1 pole, 12 position per deck model shown, sells for only $21.45 or $.17875 per circuit in 100 pc quantities.

We build switches like no one else can!

DAVE N

DIVISION OF THOMAS A. EDISON INDUSTRIES
GRENIER FIELD, MANCHESTER, N.H. 03103 (603) 669-0940 · TWX 603-623-4938

60

Circle 60 on reader service card

Electronics April 15, 1968

RECTIFIER
»USES

for the Protection
of Solid State
Devices

TRON fuses are especially designed for the protection of Solid State Devices... such as semi-conductor rectifiers, SCR's, thyristors and the like--or wherever avery fast acting fuse is needed.
They provide extremely fast opening on overload and fault currents, with great limitation of the let-thru current.
If each diode is protected by aTRON fuse, the fuse will open very quickly when the current drawn exceeds the rating of the diode.
Thus when ashort-circuit occurs in adiode the fuse opens and takes that diode out of the circuit. This protects other good diodes in the rectifier which might otherwise be damaged.
TRON fuses are available in awide range of physical dimensions and in sizes from 1 /2 to 1000 amperes in voltage ratings up to 600.
For full information and time-current characteristic charts, ask for BUSS Bulletin HLS.
BUSSMANN MFG. DIVISION, McGraw-Edison Co., St. Louis, Mo. 63107

FOR MODERN ELECTRICAL PROTECTION ... INSIST ON

SUPPLIED THE ECONOMICAL WAY ...THRU DISTRIBUTORS

tS S

QITAIÀITY

FUSES

Electronics April 15, 1968

Circle 61 on reader service card

61

NEW
SERIES
MEATO
Min with the

TOTAL COST

PER

CHARACTER

lIip N*CLLAUMDPESS: * POLARIZED 411 FILTER

* BEZEL

* MOUNTIN

1

STUDS

SIMPLE FRONT PANEL MOUNT

FEATURES:
* Brilliant 1-inch high characters * Readable at 50 feet--in bright daylight ambient * Low Current *LowVoltage*1,000,000 hours lamp life* No costly rectangular front panel cutouts
J DISCON CORPORATIO
(T

62

Circle 62 on reader service card

Electronics Review

sisted that the Pentagon instead

come up with a new craft that

would use the same Phoenix mis-

sile system and engine as the F-

111B, but would be much lighter

and more maneuverable and would

be designed strictly for naval op-

erations.

Substitute. Early this month, the

Senate reached acompromise with

the Navy and Pentagon by provid-

ing nearly $300 million for devel-

opment of the alternate model

during fiscal 1969; this includes

funds for additional F4J fighters

as an interim craft. Four air-

craft

companies--Ling-Temco-

Vought, Grumman Aircraft, North

American Rockwell, and McDon-

nell Douglas--are already working

on designs. The timetable now

calls for the project to reach its

contract-definition phase by Jan-

uary.

The furor over the Navy version

was still going on when trouble

struck the Air Force version, the

F-111A. Two of the first six planes

sent to Thailand for combat trials

were lost during sorties against

North Vietnam.

Clifford, who has had to devote

alot of his time to F-111 problems

during his first 30 days on the

job, immediately grounded the

other four planes, dispatched an

investigating team to Thailand, and

ordered more extensive testing of

the F-111A's remaining in the

States. Air Force officials, eager

for a scapegoat, hinted that the

plane's terrain-following radar may

have contributed to at least one

of the crashes. The true cause may

not be known for several weeks.

Thumbs down. The F-111 pro-

gram experienced an earlier set-

back late last year when Britain

canceled a large order for the

planes as part of its retreat from

a worldwide military role. Only

the Australians still plan to buy

the craft, and only in limited num-

bers.

Nevertheless, McNamara's plan

for a versatile aircraft isn't yet a

complete washout. The difficulties

with the F-111A will undoubtedly

be worked out. Work on the

bomber version, the FB-111, is

progressing, and the plane appar-

Electronics lApril 15, 1968

ently will be asuccess even though it's limited by a small bomb load. And the reconnaissance version, the RF-111, seems asure success.
Industrial electronics
Change in the guard
Security at many plants is about as old-fashioned as the technology within is modern. At some installations, security still means alonely codger checking identification cards at the front gate.
Bernard M. Van Emden, head of Litton Industries' Applied Technology division's Security Identification Laboratory, thinks electronics can do the job better, faster, and probably cheaper. He's designed a system that uses magnetically encoded in cards that would be difficult for even the gang from television's "Mission Impossible" to forge.
In or out. The card is inserted into acard reader, which scans the encoded data. Called an Autoguard, the reader can be connected to an alarm system that would be sounded if the encoded data isn't correct. Connected to an automatic (loor, the reader would signal the unlocking mechanism when the data is correct.
The card, called Magna-Badge, is about the same size as acredit card and is encoded in one of two ways: for small amounts of data-- up to 130 bits--a circular track is used; for large amounts of data-- up to 800 bits--a multitrack, lineal configuration is used. The data can be erased and the card can be encoded as often as necessary. Photographs and other visual data can also be placed on the card.
"Duplicating any part of the system," says Van Emden, "would be avery expensive and time-consuming operation. Besides which, you must first know the code structure, and that can only be obtained from someone on the inside."
Recording data. The encoder can be a simple keyboard that is manually operated or a printer that is
Electronics April 15, 1968

N
TOTALLY NEW

5 7 00 SERIES

DECODER/DRIVER

* MEDIUM
1SCALE INTEGRATION
I* INTEGRAL HIGH
CURRENT DRIVER

Chess's Mounted Iitegral Leads
Chassis Mounted Cerd
Solder Pads

* BCD to 7 LINE with and without MEMORY

* COMPACT PACKAGE :Plug -ln Mocel only 1 xl'x.35)

FEATURES
* Decodes and directly drives all available 7 segment incandescent readouts -- up to 80 MA per segment * Complete package--no additional corn onents required
ORA

125c

. T LeiuDEPDALE.

Circle 63 on reader service card

63

You can selectively transfer 216 circuits with these two Ledex switches and only 10 wires
As you can see from the diagram, our Selector Switches can do alot of work in asmall space. And they'll do many different jobs, some smaller, some larger. That's why they are known by many different names.
To some engineers aLedex Switch is aprogrammer or abatch accumulator. To others it's alight dimmer or binary-to-decimal converter. To you it might be a sequencer, athermo-couple scanner, amemory pulse decoder, adestruct switch or an intervalometer.
We have 36 stock models, 28 and 100 VDC, to give you aquick start on your prototype. Or, if you've got a special problem, our engineers will come up with a custom model.
Our 36-page catalog tells all about Ledex Switches. For your copy just drop us anote. Or, call and we'll talk about your special application.
Write for catalogs on Rotary Solenoids, Push-Pull Solenoids, Stepping Motors and Rectifiers. Also check our "Package Control Service" for black box and timed switching solutions.

Electronics Review
controlled by an on-line computer. The price of the simplest system-- including encoder, card, and card reader--is about $500; cost increases with complexity.
Litton is also looking into fingerprint identification. The company is seeking to code aprint digitally and then code this magnetically on the card.
Van Emden sees other possibilities for the system. For example, the Magna-Badge system could be used as atime card when coupled with an electric clock containing a readout device. Other potential applications include elevator systems in which the Autoguard could be set for certain floors, and library systems in which book-checkout procedures are controlled.
A paper will be presented on this system at the National Symposium on Law Enforcement Science and Technology in Chicago, April 18.

In this example, 2 manually operated switches, one 10position and one 24-position, let you select any one of 216 circuits.
10 wires are all you need.
A 10-position remote Ledex Switch selects any one of 9 circuits on a9-pole 24-throw Ledex Switch. This gives you a 1-pole 216-throw selector. Combinations are unlimited.

·eri oz.

Size IX' x3' x6X."-

.../0 Size IX" x2' x2,4".

LEDEX DIVISION, LEDEX INC.
123 Webster Street, Dayton, Obi,. 4.'402 ·phone (113) 224-9891 Custom Circuitry d Controls

64

Circle 64 on reader service card

Manufacturing
Turned off on real time
Last fall, officials at ITT Semiconductor asked themselves whether their integrated circuit production would grow enough by the mid70's to justify the use of a realtime computer system to control testing, inspection, and processing. The answer, after ajoint study by ryr and the Burroughs Corp., is no.
When rrT started the study last November [Electronics, Nov. 13, p. 52], Irwin A. Horowitz, director of information systems, said, "If our concept proves feasible, rrT will spend about $10 million for extensive centralized computer IC test equipment in the next five years."
However, the Horowitz team found that areal-time system using two large digital computers would be too expensive. For one thing, the study showed that about 80% of the money would have to be spent for interface gear, the equipment that serves as the real-time link between the computers and the test and production stations.
Off line. Horowitz is now look-
Electronics lApril 15, 1968

ing at an off-line system that uses centralized digital computers but
isn't in real time. Each station will have atape machine to accumulate test and production results. The tapes can then be scrutinized by off-line computers.
Triggered by a computer, an adapter on the tape machine reverses direction so that segments of the tape can be used to reprogram a station to test a different batch of ic's. Horowitz thinks the two- or three-hour delay in getting reports will be more than offset by the potential savings of several
million dollars.

Now from Sprague!
All the advantages of tantalum in one LOW COST capacitor!

For the record
The big picture. Among the new developments unveiled at the National Association of Broadcasters' show in Chicago this month was a 3-by-4-foot color television display system suitable for use as a studio monitor. The system, developed by General Electric, operates on a proprietary principle called color selection. GE, which says the display could be expanded to 6by 8feet, will begin selling the system next year at $35,000.
Groovy. CBS Laboratories, under the direction of Peter C. Goldmark, has developed aseven-inch record that plays for two hours on each side. The record, which has afrequency response of up to 5,000 hertz--not good enough for high-fidelity reproduction--runs at aspeed of 81/3 rpm. CBS, also developed athinner stylus and special playback unit for the record. The longer playing time was obtained by squeezing in 700 grooves per inch. Electronics IApril 15, 1968

EPDXY- DIPPED TANTALEX R CAPACITORs
For industrial, commercial, and entertainment electronic applications where tantalum capacitors where previously too expensive!
--le -Type 196D Solid-electrolyte Tantalum Capacitors have special epoxy-dip coating which keeps costs down without sacrifice in dependability. Positively seals capacitor section while providing excellent electrical insulation. Protects against mechanical damage in handling.

High stability-- very little capacitance change, even at outer limits of operating temperature range.
Low dissipation factor of these capacitors permits higher ripple currents.
Meet environmental test conditions of Military Specification MIL-C-26655B.
Prime capacitance and voltage ratings. Based on rating popularity of other types of solid tantalum :apacitors.
Designed for continuous operation at temperatures from --55 C to +8f C.

Radial lead design for plug-in mounting on printed wiring boards. The .250" lead spacing will fit standard .125" grids.

For complete Technical data, write for Engineering Bulletin 3545 to Technical Literature Service, Sprague Electric Company, 35 Marshall Street, North Adams, Massachusetts 01247.

Now available for tast aelivery

from your Sprague Industrial Distributor

SPRAGUE COMPONENTS -

CAPACITORS TRANSISTORS RESISTORS INTEGRATED CIRCUITS THIN-FILM MICROCIRCUITS INTERFERENCE FILTERS
·SC.5116

PACKAGED COMPONENT ASSEMBLIES FUNCTIONAL DIGITAL CIRCUITS MAGNETIC COMPONENTS PULSE TRANSFORMERS CERAMIC-BASE PRINTED NETWORKS PULSE-FORMING NETWORKS

SPRAGUE'
THE MARK OF RELIABILITY

Sprague and

are register .d tradernaraS of the Sp,ague Clectr.c Co

Circle 65 on reader service card

65

MINIATURE SIZE RELAY El CONTACT RATINGS: Contact Material: Rhodium. Maximum Voltage (Volts): 50 VDC, 150 VAC. Maximum Current: Switch, .500 amp. Carry, 2.5 amps. Maximum Power (Watts, DC): 6Watts. Resistive or properly suppressed (VA. AC): 10 VA. Maximum Resistance Initial: 100 milliohms. End-of-life: 2 ohms. Peak Breakdown Voltage: 500 volts rms.
Life & Reliability At Rated Load: 20 x10' operations. Dry Circuit: 500 x10 operations. OPERATING PARAMETERS: Speed: Depending on sensitivity and number of poles, the speed for miniature size relays is from 1msec to 2'A msec, including contact bounce and coil time. Insulation Resistance: Coil to ground: 50 megohms (min). Coil to contact: 500 megohms (min). Temperature Range:
--50°C to +105°C. Vibration: 106 ® 10-55 cycles/sec (open or closed). Shock: 15G (min).

STANDARD SIZE RELAY ID CONTACT .RATINGS: Contact material: Rhodium. Maximum Voltage (volts): 150 VDC. 250 VAC. Maximum Current: Switch.1.5 amps. Carry, 6amps. Maximum Power
(Watts, DC): 25 watts. Resistive or properly suppressed (VA. AC): 40 VA. Maximum Resistance, Initial: 50 milliohms. End-of-life: 2ohms. Peak Breakdown Voltage: 500 volts rms. Life & Reli· ability, At Rated Load: 20 x10' operations. Dry Circuit: 500 x10' operations. OPERATING PARAMETERS: Speed: Depending upon sensitivity and number of poles, the speed for standard size relays, including contact bounce and coil time, is: 2/: msec to 6msec. Insulation Resistance, Coil to ground: 100 megohms (min). Coil to contact: 2000 megohms (min). Temperature Range: --50*C to +105°C. Vibration: 10G ® 10-55 cycles/sec (open or closed). Shock: 15G (min).

If one of these dry reed relays won't do the job,
Call us.

You'll find a new line of dry reed relays at Adlake. Both standard and miniature sizes. Single, double, and 4-pole design. But if we don't have the relay you need, don't give up on Adlake. We can work with you in solving your circuit design problem. Just call us and we'll put you in touch with an engineer who spe-

66

Circle 66 on reader service card

cializes in dry reeds. He can help you develop the relay that's best suited to your needs. In addition to dry reeds, we have the world's most complete line of mercury-wetted and mercury-displacement relays. So don't forget our telephone number. It's the one to remember when quality and service count.

THE ADAMS & WESTLAKE COMPANY
A SUBSIDIARY OF ALLIED PRODUCTS CORPORATION
Elkhart, Indiana, U.S.A. 46514 ·(219) 264-1141
TWX 219 522 3102 · TELEX 25-8458 · CABLE ADLAKE

Electronics jApril 15, 1968

vvasnington 'Newsletter

April 15, 1968

U.S. maps 10-year oceanology effort

The Administration will soon issue awhite paper spelling out the major details of aplan to make the 1970's a decade of international ocean
exploration. The paper will disclose that the U. S. is willing to spend from $3 billion to $5 billion on the program over the decade if other
countries agree to make substantial contributions. Informal talks with other nations, including the Soviet Union, indicate they are interested.
The domestic U. S. oceanographic program is now funded at about $500 million annually. If approved, the new project would push U. S. spending in this field to $1 billion ayear.

L.A. studies aimed at clearing the air

The Government, stepping up its efforts to help solve urban communications problems, has chosen Los Angeles as the site for two pilot projects.
The Office of Telecommunications Management is cooperating with Los Angeles offi:-..ials in astudy of the city's communications administra-
tion. The seconu.project, aimed at hitting upon the 'best possible utilization" of the frequency spectrum, is ajoint effort of the city, the Office of Telecommunicadons Management, the FCC, and the President's task force on communications policy.

IC makers start work on Sentinel

Hybrid integrated-circuit makers are feeling the first impact of production dollars in the Sentinel antiballistic missile program. RCA, Motorola, and Texas Instruments have received $5 million each for IC production and preproduction engineering. The Army estimates that 7to 9million IC's will be needed for the computers and radar.
Most of the initial production money, $85.5 million, will go for electronic systems and components. Raytheon is getting $19 million for the
missile site radar, General Electric $1.7 million for the perimeter acquisition radar, and Lockheed Electronics $1.7 million for data processing equipment. The direct payment to the prime contractor, Western Electric, is $28 million. The contracts are for six months, ending September 30.

Comsat gets start on worldwide net

Comsat has taken the first step toward apermanent worldwide tracking network. Operated full time, the network will replace the tracking and
control now performed part time on communications antennas. Acting on behalf of the Intelsat Consortium, Comsat has just contracted for atrack-
ing station in Fuchino, Italy, that has a 44-foot antenna dish. The Fuchino station was made available when the Italian communications network put anew facility into operation at anearby site. The newer station has a90-foot dish.
Intelsat expects other older stations to become available as soon as newer facilities go on line.

Intelsat 3.5 bidding reopened by Comsat

Comsat has rejected the only bid it received on the Intelsat 3.5 communications satellite--from TRW Inc.--and is now asking for new proposals byApril 22. It's relaxing two specifications to attract more industry interest this time around. The new ground rules call for delivery in 15 months, against 12 in the earlier specs, and bidders now have achoice of offering

L.1.1l11111...

I I A pr il

M 1 net,

67

Washington Newsletter

either the originally specified configuration of one broad earth beam and two spot (squinted) beams of 6° each, or only two spot beams.
In rejecting the TRW bid, Comsat called the offer unresponsive to the request for proposals. TRW had said its first satellite would be ready in 15 months instead of ayear, and Comsat indicates that other companies
would have bid if this longer delivery time had originally been allowed. Insiders feel TRW probably figured that even though it was exceeding the delivery schedule, it would, as sole bidder, win the contract by default.

Pentagon cools it on IC designs

The Defense Department is standing by its pledge to maintain ahandsoff attitude toward integrated-circuit designs. It appears that military officials are now concerning themselves only with the form, fit, and function of IC devices, not with their design.
This is in keeping with the Pentagon's policy paper on microelectronics
issued last April, adocument that bars interference in the relationship between systems designer and IC supplier. As long as asystem's performance is up to specifications, the Pentagon is staying out of the way.
One industry official comments: "We're enjoying this now, but Idon't know how much longer they can carry it off. My guess is not much longer
--maybe ayear."

Controversial F-12 heating up another election campaign?

The F-12 supersonic fighter, which sparked apolitical controversy during
the 1964 Presidential campaign, may do it again in '68. From abattle within the Pentagon between civilian backers of the
F-106X and Air Force supporters of the F-12, the struggle is suddenly mushrooming into apolitical issue. Both sides have been busy lining up support in Congress, with the Pentagon's civilian officials openly declaring they'll fight Congressmen who'd kill the F-106X program to pave the
way for the F-12. The Air Force, which wants the F-12 as the interceptor for the Air-
borne Warning and Control System (Awacs), picked up valuable ground when the Senate Armed Services Committee cut back the F-106X program. The committee trimmed from the fiscal 1967 budget $24 million that was earmarked for modifying the F-106 with new electronics and mis-
siles.

Second uhf meeting stalemated, but Lee will try, try again
68

FCC Commissioner Robert E. Lee is adetermined man. A strong advocate of uhf television, he tried again this month to get tv-receiver manufacturers to agree to detent the uhf tuners on their sets [Electronics, March 18, p. 69], but the Chicago meeting ended in astalemate. A conference of tv makers called by Lee last month flopped because few firms attended. But Lee isn't giving up; he plans to call athird meeting next month, this one in Washington.
Uhf broadcasters are trying to get set makers to adopt new, solid state all-channel tuners, but the manufacturers claim the devices would only add to the cost of the sets and would have no sales value. An additional problem is that only an estimated third of all present sets are equipped with automatic frequency controls, devices providing the fine tuning that detent tuners generally need.
Lee's purpose in pressing for these meetings is to get set manufacturers to act voluntarily on this matter. The FCC can force them to detent uhf tuners, but only after alenghy rule-making process.
Electronics IApril 15, 1968

The QRC solves the size / ,Dower / regulation problem by combining all silicon, low-voltage series regulator circuitry with
high-speed transistor switching techniques.

Sorensen High Performance WIC Series:

The QRC Series covers awide 'arget area without performance trade offs. Standard features include excellent regulation fcr voltage and current, fast response lime (.5.25msec.), and surprisingly small size for power cutputs to 1200 watts at ambient temperatures to 71 C.
Some laboratory power sources affer high power levels, but are bulky and, by today's e.andards, are unregulated. Others offer ecellent regulation specifications, but are inefficient and, if high-power levels are desired, become large heat sinks. Sorensen QRC's are high e`ficiency, compact power sources which lave excellent performance characteristics witi prices

starting at $325. Seven models are available trom stock, covering the range of 0-40Vdc at currents to 30 amperes.

Additional features resulting from the utilization of sophisti-

cated regula'ion techniques incluce low ripple

V r.m.s.);

output vcltage and current resolu:ions of 001% and 0.05%,

respectively; remote programming in both the voltage and cur-

rent modes; remote-sensing and a soild state automatic-

crossover indicator.

Contact your local Sorensen representative or: Raytheon Company, Sorensen Operatior, Richards Avenue, Norwalk, Connecticut 06856, TWX 710-468-2940.

RAYTHEON

for more data on fibs versatile instrument ...Call Sorensen: 203-838-6571

Electronics April 15, 1968

Circle 69 cn reader service card

69

Electronics April 15, 1968

acdc: Now in its third year of forever.

`6%,4444 444..n.'44444...444, 66.46 ...................... %SS, %SS ......... .. 6%44% ...........

44

,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

,,,,,,,,,,,,,

Circle 70 on reader service card

44601, 46604844 006666664446 1,66 6$0604.41400 06 606446448M
40 O046 64 , 441100 64 4 1e·46640604

646 40
44 · 4444

684404 SI ·a
4466004 44406 4 6466 46 4 ··

116:4141:41141.4116110:11114.1111.··

6 6611 11066 111164 4II,4·0

NO CONTEST if you're looking for 1to 2 watts
of continuous audio power

:SENSITIVITY

4 BIASING CONDITIONS

See for yourself why General Electric's silicon monolithic IC's can't be beat.
No matter what your application, the PA234 or PA237 probably fits ...and you save on design expanse. See if you can draw a path from the feature most important to you. to the PA237 amplifier in the center of the puzzle. If you can get to the center, the PA237 is tight for you. If you want to prove it to yourself. tell us your expected application and we'll send you a free PA237 to put to the test. Simply tear out this page and send it with your name, address, title, company, and PA237 application to Product Manager, Monolithic Audio Amplifiers. General Electric Company, Northern Concourse Office Bldg.. North Syracuse, N.Y.
For more facts, turn the page.

SEMICONDUCTOR PRODUCTS DEPARTMENT

GENERAL

ELECTRIC

Save design expense. Take advantage of the PA237's
application versatility.

Because General Electric's PA237 operates over a supply voltage range of 9 to 27 volts, you can probably use this one circuit for most of your applications and save money. It is capable of delivering up to two watts of power to resistive or inductive loads. (Pictured actual size.)

General Electric's PA234 gives you the lowest total cost for a 1-watt amplifier function through a combination of low device cost and minimum number of outboard components. (Shown actual size.)
14

14 01

02

08

INPUT

The PA237, shown in this circuit diagram, converts 8 mV of input signal to 2W of continuous, low distortion output power.

PA234 audio amplifier delivers 1 watt of continuous power to a 22ohm load from a 22-volt supply.

Now you can use asingle IC for most of your audio applications

by simply varying its bias.

General Electric PA237 silicon monoIithic audio amplifier is designed to have its biasing network external to the chip. Thus .appropriate bias-
ing for any power supply from 9- to 27-volts is readily achieved.
External biasing permits operation with Class A, Class A-B, or Class B outQut modes. The input may be biased for voltage or cur-
rent sources as well as differential signals.
In addition to the PA237's wide range of supply voltage and bias
alternatives, feedback may be ap°lied to the amplifier to allow adjustment of stability, input and output

impedance and amplifier sensitivity. Simple AC and DC feedback networks are employed to provide excellent stability with frequency and temperature.
General Electric's 1- and 2-watt low-distortion amplifiers are packaged in an 8-lead dual-in-line plastic package with a tab for transferring heat te a printed circuit board. This means easy insertion into the P.C. board and easy heat sinking too. General Electric's PA234 is the
ultimate in low cost 1-watt monolithic audio IC's. Its low cost plus
the least number of outboard components of any audio amplifier on

the market makes the PA234 the most economical alternative for
achieving one watt of audio power. Both General Electric's PA234 and
PA237 offer you outstanding per-
formance and top reliability in a wide range of circuit applications. These varied uses include phonographs, dictating equipment, tape player/recorders, and TV, AM, and
FM receivers. Plus: the PA237 can drive inductive loads or provide voltage regulation for 1% typical over a 9- to 27-volt range. For more
information on how GE can save you design expense and cash outlay circle number 515.

Here are some other outstanding GE semiconductors
inth ¡I IIt on which you can depend.
11

Industry's most predictable UJT saves time and money.
Stand-off ratio spread 3%! ! Oscillator frequency shift .6% max.! (-15 C to 65 C)
GE's D5K1 and D5K2 planar complementary unijunction transistors offer greater stability and uniformity than any UJT previously available. They have characteristics of standard unijunction transistors except that, being complementary, their currents and voltages are cf opposite polarity. For most applications, polarity is t unimportant.
The D5K1 and D5K2 -40.1f1> combine planar and integrated circuit techniques resulting in a much tighter intrinsic-standoff ratio distribution and lower saturation voltage. This gives them both a new high level of performance predictability versus temperature.
Timing stability of 0.5% is achievable without the necessity of expensive temperature testing on individual devices to determine the compensating resistor. For more details circle number 516.

emeael..111.
····

1200-volt, 400-amp
PRESS PAK
silicon rectifier costs less.
If you want a high power silicon rectifier diode with the same proved, all-diffused construction of the A90 series, General Electric offers the A390 PRESS PAK. The package innovation delivers far more continuous currert tnan comparable stud-mounted devices, and it's smaller, too.
The new PRESS PAK package, using pressure contacts, allows double-side cooling to significantly reduce thermal resistance and, therefore, ilcrease current ratings about 60%. Result: You get more average amps per dollar.
Lightweight, hermetically-sealed PRESS PAK also features reversibility of mounting, thus eliminating the need for special reverse polarity units. And it comp,ements many SCR's already in the PRESS PAK package. For more details, circle number 517.

Now you can custom tailor tiff characteristics to meet your specific needs.
With General Electric's D13T1 and 1:713T2 programmable unijunct on transistors (PUT) yoL can now program unijunction characteristics such as n, R., 1p, and I,, to your specific needs by adding two external resistors.
Generally, the D13T gives programmability withoLt increasing circuit comple <ity. In fact, it often reduces circur cost. And the PUT offers tight peramee - specifications, high sensitivity, low unit cost. low leakage current, low peak point current, low forward voltage, and fast, high-energy trigcer pulse 'oo.
D13T2 is specifically characterized for long interval timers and other applications requiring low leakage and ow peak point current. The D13T1 has been characterized for genera' use where low peak poi -it cur -eit is not essential. Circle number 518.

I

For more information on these and other General Electric semiconductor products, call or write your GE sales engineer or distributor, or write General Electric Company, Section 220-63, 1 River Road, Schenectady, N. Y. 12305. In Canada: Canackan General Electric, 189 Dufferin St., Toronto, Ont. Export: Electronic Component Sales, IGE Export Division, 159 Madison Ave., New York, N. Y. 10016.
SEMICONDUCTOR PRODUCTS DEPARTMENT

GENERAL

ELECTRIC

Circle 75 on reader service card --3-

Acompletely new instrument from Supply with plug-in conversion

Buy the basic LS Series
Amilkate

With this plug-in accessory it becomes aHigh Precision Power Differential Voltmeter that obsoletes any instrument now offered for this service

AIN111111.

i6

(11

[7'1

111

. ·

· J

Basic Non-Metered
Model
LS-511 LS-512 LS-513 LS-515 LS-516

Voltage Range
0-10VDC 0-20VDC 0-40VDC 0-120VDC 0-250VDC

Max. Amps at Ambient of ,',

OM. VM Accessory

30"C
2.8A 1.8A LOA 0.33A 0.1A

40"C
2.5A 1.6A 0.9A 0.29A 0.09A

50'C
2.1A 1.3A 0.75A 0.25A 0.08A

60 C
1.7A 1.1A 0.6A 0.21A 0.07A

Price 'i Model

$375 375 375 375 380

LS-DM1
LS-DM2 LS-DM3
LS-DM5 LS-DM6

Price
$85 85 85 85 85

1 Current rating applies over entire voltage range. Ratings based on 55-65 Hz operation.
2 This price is for Precision Power Source only. Addition of Differential Voltmeter Accessory Plug-In (next two columns) is necessary for unit to function as High Precision Power Differential Voltmeter.

· Draw power as you measure voltage--The first and only differential voltmeter to furnish high stability power output while being used as a voltmeter ... no need for a separate power supply.
· 2 meters-- Monitor both voltage and current simultaneously and continuously.
· Guaranteed for 5 years--The only 5-year guarantee that includes labor as well as parts. Guarantee applies to operation at full published specifications.
· All-silicon design for maximum reliability
· Convection-cooled for convenience and reliability ... no blowers or heat sinks.
· 5 voltage ranges: 0-10, 0-20, 0-40, 0-120, 0-250VDC--Wide selection of ranges to suit your specific needs.
· Illuminated Digital Readout Millimatic(TM) gang dialing-5-digital voltage dials with automatic decade turnover provides convenient precise adjustment.
· Only 51/ 4 " high --Convenient half rack size for rack or bench use.
· 0.01% ± 1mV accuracy
· Stability 0.001% + 100)JV for 8hours

· Completely protected: short-circuit proof; continuously adjustable automatic current limiting
· Overvoltage protection available as low cost add-on accessory
· Rubber Feet provided for bench use.
Power Supply specifications for Voltmeter same as for Power Supply--see next page

OVERVOLTAGE PROTECTION

For Use With

Model

LS-511 LS-512 LS-513 LS-514

(0-10VDC) (0-20VDC) (0-40VDC) (0-120VDC)

LHOV-4 LHOV-4 LHOV-5 LHOV-6

Adj. Volt. Range
3-24 V 3-24 V 3-47 V 3-70 V

Price
$35 $35 $35 $35

LAMBDA

1.: 1. (7 "1 1( ()NICS
:,1513110A1)14.1.LOW 11,,AD· MELVILLE. L I NEW 5, 115

(7 (HI P.

· E,Iff, 099 9200

·

su.slo.ear

VEECO HIGH VACUUM EQUIPMENT:LAMBDA POWER SUPPLIES

Lambda...High Precision Power to Power Differential Voltmeter

,,··· *****

_

_-4_-¡,--._ 1*---M--ie-Precision Power Source

·

·

···· Mt. «ed.

ist Ç.
-.

PO., Sy·Mt V

e

1.4

With this plug-in accessory it becomes a Metered High Precision Power Supply that offers all these features

Basic Non-Metered
Model

Voltage Range

LS-511
LS-512 LS-513 LS-515
LS-516

0-10VDC
0-20VDC 0-40VDC 0-120VDC 0-250VDC

Mae. Amps at Ambient of ,',

Metered Accessory

30 C 40 C 50 C 60 C Price ,' Model

Price

2.8A 2.5A 2.1A 1.7A $375 LS-FM1 $55 1.8A 1.6A 1.3A 1.1A 375 LS-FM2 55 1.0A 0.9A 0.75A 0.6A 375 LS-FM3 55 0.33A 0.29A 0.25A 0.21A 375 LS-FM5 55 0.1A 0.09A 0.08A 0.07A 380 LS-FM6 55

1 Current rating apples over entire voltage range Ratings based on 55-65 Hz operation.
2 This price is for non-metered Precision Power Source. Addition of Metered Accessory Plug-In (next two columns) is necessary to have Metered High Precision Power Supply.

·

· P ·

-171

n1

-jr:'

11- 11- 1117«,

glee-14

· 0.0005% plus 100 MV regulation--Best of any high stability power supply in this price range.
· Ripple-35pV rms; 100uV p=p.
· Twice the power in aconvenient 1 /2 -rack package
· 2 meters-- Monitor both voltage and current simultaneously and continuously.
· Guaranteed for 5years--The only 5-year guarantee that includes labor as well as parts. Guarantee applies to operation at full published specifications.
· Multi-Current-Rated for 30 C, 40 C, 50C, 60'C --Covers temperatures most often encountered in laboratory work.
· 5 voltage ranges: 0-10, 0-20, 0-40, 0-120, 0-250VDC--Wide selection of ranges to suit your specific needs.
· Illuminated Digital Readout Millimatic(Tm) gang dialing-5-digital voltage dials with automatic decade turnover provides convenient precise adjustment.
· Only 51/4" high--Convenient half rack size for rack or bench use.
· 0.01% ± lmV accuracy
· Stability 0.001% + 100)JV for 8 hours

· All-silicon design for maximum reliability
· Convection-cooled for convenience and reliability ... no blowers or heat sinks.
· Remote programing by changes in voltage or resistance for convenience in systems, test equipment and automatic equipment applications.
· Auto Series/Auto Parallel with Master-Slave tracking
· Constant I/Constant V by automatic crossover
· Completely protected: short-circuit proof; continuously adjustable automatic current limiting
· Overv.oltage protection available as low cost add-on accessory
· Rubber Feet provided for bench use.

OVERVOLTAGE PROTECTION

For Use With

LS -511
LS-512 LS-513 LS-514

(0 -10vDC)
(0-20VDC) (0 40VDC) (0-120VDC)

Model
LHOV-4 LHOV 4 LHOV 5 LHOV-6

Adj. Volt. Range
3-24 V 3-24 V 3-47 V 3-70 V

Price
$35 $35 $35
$35

Quick guide to bright, legible, wide angle readouts

Series 360H Displays 2" high charac-
ters easily read from over 50'. Yet unit is just 3" H x 2" W x 7.75" D. New lens system provides bright, crisp display.

CRT Display 10-gun CRT projects single-
plane digital or word displays onto fluorescent screen. Easy reading, even in direct sunlight. Wide viewing angle. Ideal for instrumentation applications.

Series 160H Exceptionally large viewing area (1.56" H x 1.12" W for overall size. New lens system increases character brightness; reduces chance of reading error. Message lines may be displayed simultaneously with symbols.

Series 80 Large screen unit particularly suited for annunciator applications ... factory call systems, production control boards,
etc. Message or character 33/s" high; can easily be read at 100', 160° viewing angle.

Series 10H It's the world's most popular readout. And we've improved it. New lens system increases character brightness 4 times. Greater clarity at wider angles and longer distances, even under high ambient light. .937" H x.937" W viewing area. Mil-spec version also available.

Series 345 IEE's smallest rear-projection read-
out. Viewing area .38" H x .34" W. Based
lamps. Low cost. Individual readouts plug into permanently wired housing for quick message change. Easy front panel access.

Series 120H Miniature (.62" H x.62" W)
rear-projection readout. New lens system
increases character brightness 50%. Easily read from 30' even with high ambient light. Quick disconnect lamp assembly for speedy lamp replacement.

Series 220H Miniature, plug-in, rear projection readout meets MIL -R-39027. .62" H x.62" W viewing area. Special lens system increases character brightness 50%. Excellent readability from wide angles and long distances.

Series 875 Miniature, 24-position, rear-projection readout with .62" H x.62" W viewing area. Overall size just 1.39" H x.90" W x 3.095" D. Exceptional character brightness and clarity. Quick disconnect lamp assembly for easy replacement.

IC Driver/Decoders Small, solid-state units for IEE Series 10H, 120H, 220H, 340 and 360 readouts. All models accept avariety of binary codes for decimal conversion. Take normal signal voltage. Draw less than 2 ma. (Many options, including memory.)

Any characters desired. Any colors or combinations. Any input, BCD or decimal. Any input signal level. Any mounting, vertical or horizontal. Many sizes. Many configurations. Many options and accessories. Many brightness choices. Long lamp life (to 100,000 hours).

Circle 76 on reader service card

PEE
Industrial Electronic Engineers, Inc., 7720 Lemona Ave., Van Nuys, California

TTL Trends
from Texas Instruments

e 0

0

00·

·000 · 0..0

how the TTL circuits that erabled Systron-Donner
.ack the instrument space barrier. Result: the new Thin
Line counter-timer series... pack ing nine-digit readout with up to 12.4 GHz capability in chasses only 13/4"high.
Turn page for story.

RE:Y. LE

GA-1F-

411114MMilli.enirej

· --

3new shift registers expand industry's broadest
logic line

These complex-function TTL shift registers are far more than basic registers. Applications include shift counters, Johnson and ring counters, and shift-register generator counters.
These registers incorporate additional gating as well as input and output connections, and are recommended for many storage and counting applications in addition to such shift functions as serial-toparallel, parallel-to-serial, rightshift and left-shift operations. In all cases, substantial savings in packages, interconnections, design time and overall costs will be realized.

PR.. /A P111,11IS 51,51128 MIS. t cm

I, 1/

1

01111

16
Ji*

15 14 13

P I,

MI,

I 00C'

12 11 10 9

iI

ISI I

PR! 11

CS.

CI I

CUR

«LI IA

CM

clock input. Also, the circuit has asynchronous loading capability from two strobe-controlled sources.
SN7495 4-bit shift-right, shift-left register This parallel or serial-input shift register incorporates four ANDOR-INVERT gates, one AND-OR gate, six inverter-drivers, and four R-S master slave flip-flops.
This versatile register can be used in a wide variety of applications, including serial-in, rightshift/left-shift, and parallel loading operations.

1234 5678

P11511 IA PRI II 1111111, IC 111 1.1 1 IP V

Poll! I `,,1.1e

C1111 .

MAR

...

LI.

S1I1R0I0A1l

16 15 14 13 12 11 10 9

SN7494 4-bit shift register
This parallel entry, serial shift register includes four AND-OR-INVERT gates, four inverter drivers, and four R-S master-slave flipflops. The result is a versatile circuit which performs right-shift operations as a serial-in, serialout register or as a dual source parallel-to-serial converter.
All flip-flops may be cleared simultaneously -- independently of

PRI 1

IIP, 00C

C100i

RA

R

ClIAR

CORR

PRI
MICR RC
11AR

P
CMC RP MAR

C1OC
R1 CAL.

1234 56 78
C100 PR.. A 11 SO II PAIS. C V, P111115 MIS. ! MIS.

SN7496 5-bit shift register
This register consists of five R-S master/slave flip-flops, with gates and inverter drivers, connected

as a shift register to perform parallel-to-serial or serial-toparallel conversion of binary data. Since both inputs and outputs to all flip-flops are accessible, parallelin/parallel-out and serial-in/serialout operations may be performed.
A common clear line and strobecontrolled, individual presets permit loading of any binary information into the register. Preset is independent of the state of the clock input.
A note from you, on your company letterhead, will bring this goldmine of information ...data sheets on these 3 new shift registers plus application information on all our 54/74 counters and shift registers...a data book on the entire 74 N complex-function family ...and finally, an in-depth 48-page brochure covering all 54/74 TTL integrated circuits. Just address your letterhead request to Texas Instruments, Incorporated, MS980, P.O. Box 5012, Dallas, Texas '75222.

TEXAS INSTRUMENTS
INCORPORATED

Craftsmanship in hard materials...an industry standard

HIGH PRECISION TUNGSTEN CARBIDE -BONDING TOOLS,

SUCH AS THE ONE SHOWN IN THIS 13X MAGNIFICATION

OF AN ULTRASONIC LEAD BONDING OPERATION, WERE

PIONEERED AND INTRODUCED AS PRODUCTION DE-

VICES BY TEMPRESS

IN 1963, THE TEMPRESS CAP-

ILLARY TUBE, AN INDUSTRY STANDARD ... IN 1967, THE

ULTRASONIC BONDING TOOL, AN INDUSTRY STANDARD.

The techniques and the specialized machinery de-

veloped to produce sucrr precision products from

ultra-hard materials have not been duplicated; quite

probably will not be, for they are a result of the

unique combination of Tempress people and the

Electronics April 15, 1968

Tempress philosophy. To meet its responsibilities, Ternpress maintains a continuing expansion program, limited only by strict adherence to the Tempress Standard of Excellence. It requires as long as 11 months to train an operator for certain operations.) The same uncompromising standa'd is applied to Tempress Automatic Scribing Machines and to the entire growing fam.ly of Tempress
miniature assembly tools and production equipment.
o 'CO B 0 tO. DUAL fET.. OURTE,T 0F 011100 CARBIPE ELECTRCell
TIE1VIPFIESS
Temvess. Research Co., 566 Son X3vier Ave., Sunnyvale, CElif .94086

Circle 81 on reader service card

31

Try this $580 EAI Digital Measuring System for two weeks--FREE!

Now--you can get the EAI 6200 DVM on a two week memo billing to prove the performance claims for yourself. We bet you'll keep it, but if we lose there's no obligation. Just tell us your reasons!

What are the claims? First it's agreat dc DVM, with fea-

tures like automatic polarity, 100 microvolt resolution,

pushbutton ranging, 1000 volt overload protection and

-± 0.1% accuracy

1digit); and afew more you'll find

for yourself.

What makes it a DIGITAL MEASURING SYSTEM? Low cost modules that create an ac DVM and acounter. Not just any counter, but a 10 MHz crystal controlled counter and time interval meter that can totalize and measure period--all for only $210. For ac measurements. there's a 20 Hz-- 100 KHz converter good to 300 volts

82

Circle 82 on reader service card

with a 1megohm input impedance and packaged in a compact plug-in module for only S250.
For you systems-minded people, arack-mounted version called the 6210, with aBCD output option, costs alittle less--$550 as aDVM.
Interested? Call us--collect--at 201-229-4100 extension 6200 with aconsignment purchase order and we'll ship you one for atwo week trial (if you're in the US, that is... we do have to limit the oiler to continental US only). Or ask for more specs... they '11 be return mailed to you.

EAr

ironic Assodates, Inc., West Long Branch, New Jersey

Circle 83 on reader service card-*

Semiconductor te5t system.
Computer-control: $59,900.

The 600C is the top of our Series 600 Test System line. And, spec for spec, it's the best system in its price range. It consists of abasic Series 600 system, a rack-mounted POP-8 computer, an ASR-33 teletypewriter, acontrol panel, and asoftware package.
Our Series 600 is ahigh-speed test system for transistors, diodes and reference diodes. It can perform 100 digital readout or GD/No-Go tests asecond: Leakage. Breakdown voltage. Latching voltage. DC gain ratio. Saturation voltage. Base turn-on voltace. The whole parametric package. It's suited for production testing, incoming inspection, quality control, eliability and general engineering testing.
Series 600 equipment starts at $18,900. We also have amagnetic disc programmed system that sells for $40.950. And, of course, be :.omputei-controlled 600C priced at $59,900. You can get information on the whole series, plus specs and options, just by calling Fairchild collect at (438) 735-5461. Ask for Frank Wilber.

FARCHILD INSTRUMENTATION A Division of Fairchild Camera and Instrument Corporation 974 East Arques Avenue, Sunnyvale. Californie 94086 ;408) 735-011 TWX: 910-379-694-4.

THE °Niel:I-ACHIEVER ...

84

Circle 84 on reader service card

No other solid state pulser for under $1,000. gives you as much as our Model PG-2. Buy it for production test and you find that the development lab people prefer it for most of their development work and systems engineers keep designing it into test and operational systems. It shows up everywhere and everywhere it excels.
Maybe it's the PG-2's performance: prf to 20 MHz from 1 Hz in the double pulse mode; 16 MHz at full -±20V amplitude. Rise/fall from 10 ns to 20 ms with greater than 100:1 dynamic range between them. Widths from 35 ns to 200 ms; delay from 0 to 200 ms; DC-offset 0 to -±5V.
Or its operating flexibility: single or double pulses, normal or complement, sync pulse, plus manual one-shot. Continuously variable prf, amplitude, width, delay, rise time, fall time, DC-offset, input threshold and sensitivity. The PG-2 can be gated or triggered from DC to 10 MHz. And it is DC-coupled so that there are no low frequency or duty cycle limitations.
And probably the PG-2's outstanding reliability, operating simplicity and rugged solid state design help.
Model PG-2. Our over-achiever. $925, f.o.b. Mt. Vernon, New York. Delivery off the shelf.
Where can it over-achieve for you?
Chronetics, Inc., 500 Nuber Avenue, Mt. Vernon, New York (914) 699-4400; in Europe: 39 Rue Rothschild, Geneva, Switzerland (022) 31
o 8/ 80. Sales Offices throughout the free world; see EEM or EBG.
Electronics rApril 15, 1968

Overp ate for met; lk griphic sect-orin urposes
Gott! layer

Illustrat on is 1400X magnification cross-section through selectively p ated contact a- point shover

CINCH PUTS THE GOLD ONLY WHERE YOU NEED IT

IN THE AMOUNT YOU WANT--With Cinch selective plating you benefit from reduced gold content and the absolute control of gold thickness at the contact area. The result is a better connector at lower cost ...that al.o
helps reduce the U.S. gold drain.

In conventicnal barrel platin, he amount of gold deposited at any point is afunction of the geometry of the part and cannot be accurately controlrec
from part to part. To compensate, excessive gold deposits must be used.
but there is still no guarantee that every part will receive the minimum gold plate specified, due to the random nature of the process.

Cinch continuous process selective plating deposits the same controlled
amount of gold on every contact. Only the contact area is plated, reducing gold consumption as much as 60%.

A wide range of Cinch connectors is available with selectively plated

contacts. For information on how selective platirg can provide you with

a better product at lower ..:ost, write to Cinch Manufactur ng Company,

1501 Morse Avenue, Elk Grove Village, Illinois 60007.

c·6e14

MEMBER

© II

DIVISION

OF

UNITED-CARR

CONSISTING OF CINCH MANUFACTURING COMPANY. CINCH-GRAPHIK. CINCH-MONADNOCK. CINCH-NUUNE. UCINITE (ELECTRONICS) AND PLAXIAL CABLE DEPT.
Circle 85 on reader serv.ce card

)SPEIENHTHOILSE?
General Electric's Helium Leak Detector
will find aleak one ten-thousandth its size.

Our Helium Mass Spectrometer Leak Detector's sensitivity is like horsepower in abig car. Nlost of the time you have more than you really need; but when you do need it, it's there.
Specifically, our units are sensitive to at least 2 x 10 -n std. cc/sec. Put another way, GE equipment will--in less than one second--
detect leakage that's at a rate of an ounce of helium in ten N·ears.
But sensitivity is only part of our story. We'd

like the chance to tell you about our two-yearsguaranteed spectrometer tube filament; our reliable, long-life, solid-state circuitry; our models' case of operation and servicing; our constant sensitivity; our all-welded, stainless steel highvacuum system.
And then some. Cheek the reader service
card, or write us direct for full particulars on manual model LC-10 or automatic model LC-20. \Ve have aproduct we're proud of.

VACUUM PRODUCTS BUSINESS SECTION

GENERAL

ELECTRIC

SCHENECTADY, N.Y. 12305
LC-2

86

Circle 86 on reader service card

Electronics April 15, 1968

Only ITT has laser-controlled IC mask making.

Another reason
to buy from
"The Predictables."
Mask variations used to mean performance variations in Series 930 D-L. Now ITT initiative has eliminated the problem. An exclusive laser-controlled, fully automated mask making machine assures absolute repeatability of masks and of circuit performance.

ITTs machine, representing an order of magnitude improvement
over older processes, holds nask registration tolerances to -± 122
silicon atoms (based on the crystal lattice constant). It is tape Pro-
grammed, with memory storage capacity of 10,000 separate semi-
conductor devices, and it can complete a matched set of up to nine masks in as little as 10 minutes.
If you think all Series 930 DTL

circuits of the same type should act the same, the solution is simple: buy them from The Preciictables."
ITT predictability also extends to diodes, rectifiers, and silicon planar transistors. Ask for aquote on any
or all. They are on-tne-shelf at
your ITT distributor. ITT Semiconductors is adivision of International
Telephone and Telegraph Corporation, 3301 Electronics Way, West
Palm Beach, Florida.

TI semiconductors
FACTORIES IN FLORIDA ·CALIFORNIA ·MASSACHUSE I1S ·ENGLAN- ·FRANLE ·GERMANY ·PORTUGAL ·AUSTRALIA

Electronics April 15, 19.5E

Circle 87 on reader ser4ice card

87

Now, absolute measurement of low intensity light signals

with the EG&G Spectroradiometer System

EG&G's new series of high sensitivity detector heads allow use of the Model 580/585 Spectroradiometer System for absolute measurements of low intensity, pulsed or CW, light signals. These new detector heads, which incorporate photomultiplier tubes, complement the existing line of vacuum tube detector heads by providing approximately five decades of additional system sensitivity.
The Model 585-66 Detector Head encompasses aspectral range from 200-750 mu (ultraviolet-visible) and senses irradiant powers as low as 9x10-13 watts/cm 2-mu and irradient energies as low as 9x10 -13 joules/cm 2-mu at 450 mu.
The Model 585-63A Detector Head is now contained in athermoelectrically cooled chamber (using EG&G thermoelectric modules) to minimize thermionic dark current and the resultant noise.

A separate controller unit assures constant chamber temperature. With aspectral range from 700-1200 mu (near infrared), the 585-63A detects irradiant powers as low as 5x10 12 watts/cm 2-mu and irradiant energies as low as 5x10 -12 joules/cm 2-mu at 800 mu.
The new detector heads are provided with aregulated power supply and an internal calibration feature to ensure a stable sensitivity. Utilizing standards traceable to NBS, acomplete 580/585 Spectroradiometer System is calibrated to its sensitivity versus wavelength thereby permitting absolute irradiant measurements of both continuous and pulsed (as fast as 1ns) light sources.

Applications with the new high sensitivity detector head include measurements of phosphors, chemical reaction, electro luminescence, emissivity and reflectivity of surfaces, biochemical analysis, and other low level signals.
If you'd like more information on the EG&G Spectroradiometer System, or for that matter on any of our products, such as thyratrons, krytrons, spark gaps, flash tubes, thermoelectric modules, transformers, chokes, trigger modules, photodiodes, picoammeters, flash and strobe equipment, or light instrumentation, write: EG&G, Inc., 166 Brookline Ave., Boston, Massachusetts 02215. Tel: 617-267-9700. TWX: 617-262-9317.

Energy and average power measurements

are obtained directly from the multi-

decade meter of the Indicator Unit or

e·-* EGRE from an external recorder.
Provision is also made for output to an oscilloscope for pulsed sources.

ELECTRONIC PRODUCTS DIVISION

=A%
r3=1

88

Circle 88 on reader service card

EG&G's Model 580/585 Spectroradiometer features evv IR detector head which is thermoelectrically cooled
to minimize therm ionic dark current.
Electronics April 15, 1968

Oak's design engineers are impatient ... nothing is ever quite good enough. They figure improved products today mean better circuits tomorrow. Take these: · Oak-manufactured Rotary Solenoids and Selectors for multiple switching functions in limited space under severe operating and environmental conditions. · Molded Pushbuttons designed specifically for computers, communications and other panel equipment. · Rotary Switches with molded diallyl phthalate stators and rotors, Unidex" indexing. · Lever Switch with molded diallyl phthalate type "A" stator for miniaturization, versatility in a small area. Plus these--Rocker Thumbwheel, Pushbuttons, Lever and Slide Switches. Oak offers widest selectivity in quality switches for industrial, commercial or military requirements. In fact, Oak has more switches that meet MIL-S-3786 than all other manufacturers combined--over 24 switch products. The next switch manufacturer has six. In addition, Oak offers sub-assembly service to save you production time and costs. These are only highlights of a small part of the complete Oak line of components. Send today for Catalog 24.
DESIGNED FOR TOMORROW'S CIRCUITS!

Ph: 815-459-5000 TWX: 910-634-3353

OAK

CABLE ADDRESS: OAKMANCO

MANUFACTURING CO.
A DIVISION OF OAK ELECTRO/NETICS çoir CRYSTAL LAKE, ILLINOIS 60014

Electronics !April 15, 1968

Circle 89 on reader service card

89

Compliments of afriend -- acomplete multimeter at less than $3000

We think you'll agree that it's pretty friendly of
Cimron to put out such aflexible instrument for so little. But it's typical of the philosophy that has always guided Cimron -- customer concern. You need the most sophisticated instruments to do your work under avariety of changing conditions. And the Model 6653 gives you agreat sendoff for both systems applications and laboratory or production testing. You get 5-digit readout including overrange, with an accuracy of ±-0.01% f.s. +0.01%

of reading for six months or longer. You'll save on calibration costs. Sample rates up to 300 per second; automatic polarity and automatic ranging; AC, ohms, millivolts. And look! You also get auto ranging through six millivolt and DC ranges. It's especially hard to beat all those Cimron customer concern features like remote control and printout, maintainable plug-in pc boards, and accessible calibration and test points. Write Cimron®, Dept. B-106, 1152 Morena, San Diego, Calif. 92110.

LEAR SIEGLER,INC. CIMRON DIVISION

clrbonumny DIGITAL MU LTIM c-rzigt
MODEL 6463

April 15, 1968 ,Highlights of this issue
Technical Articles

Experimental flat-screen color television page 92

Electronics

Consumer electronics engineers look forward to flat-screen color television because

it will eliminate high voltages, the danger

of X rays and implosions, and misconverg-

ence of electron beams. To learn about the

problems that might crop up in building a

flat-screen set of conventional size, Sony

has constructed a giant experimental re-

ceiver that uses 78,000 light bulbs, 260

SCR's, and 4,000 transistors. The screen (shown in part on the

cover) has a 100-inch diagonal.

Understanding commonmode errors page 108

The operational amplifier means different things to different engineers. For example, used as an inverting amplifier, it is
free from common-mode error but does not give exceptionally high gain. In anoninverting configuration, its gain is high but common-mode error is present. In this article, the first of two on this subject, the author shows how amplifier design can minimize common-mode error.

Party-line data link page 119

Cabling can be an expensive item in adata-transmission system. A new method of linking transmitters to their corresponding receivers one at atime over asingle two-wire cable reduces
these costs. The technique also employs low-cost logic gates and flip-flops. The system can send analog or digital messages, using abinary code to address transmitter-receiver pairs.

Airborne transceiver for the military page 133

A critical problem in airborne communications is electromagnetic compatibility. Now ahigh-frequency transceiver crams 280,000 voice channels in the bandwidth used by older sets for only 28,000. It can reject asignal 120 db above that of the tuned signal and only 50 kilohertz away from it, permitting efficient operation in crowded-frequency situations where strong interfering signals are close by. The new set also per-
forms dynamic tests on itself.

Coming April 29

.Automatic in-flight checkout ·Integrated circuits in Japan

--<--Circle 90 on reader service card

91

·
9. ··· Abe

· ·

··f·ib'··e·.jIlep·yVf. ileteele1·d,e

4.*··

I.
if,

t..s..eet -,,.«eb.·.e..!>.«.-.».·,,,?.4 e1; e.· ···· · · ,_

e ·

· ·ftli · % lb . · I. ·

· le -·-·40····.·4).tesootr.ieA·b·li·-t,

·111

· ,

a:.

s..· ·

.dre

ir ·..· ····

10....evoloe,..e...e.

.·i r ote li

4; :.e· .1p

-; · .

e. lb.: 0

i ie i de "i*fr·e-:.·e*.di·>.·····.·".· ·····sIaiki> · ·

.

·

,.. - e

· · ob· ·lie·da.plit

my
ble ·

.. ·· . ·
ip.-·40···*

.

·
·

· ···e·t.···e·A·40t1 ·ew,-.·,···111······.A··:4.I,6.,·····.··0·.·1O.·b·.j·v>-.9·0

110·0···,),,.····
fillp· ·

···.. · ·.00_111, - 0.41·1e··.·A··.·

·00. · ·.(14, -·

· · ···?·I(At..· SC(e·'·eVe.,.l!00·l·*·i*Oee-eb·.*s··e··e·sebo· 4 ..·,·.··*·.····40`··0·.4···.·.···0··.(e4.··O0·r,e···*··«·,.s1i0.·*·
·0* ea e ·Elre ··· · ·

.

ear. seie·

·eiti·k-·ee·0··)*·.,0··e······o·.w0.-

····

..s.eerae.·.·,·.· ·Ob·e0(.
Orti.eiti .41 4 ··· ·
·

Z-

re-liedie4

P; e if.ele iteie e·

·ar·

1·440.

rieleePe.',1e.eleetee.:109411

eepleisinePPeaRAeee-.'*P.e*Peee.**

· -·
· ·Ir.i.i0.i4·e··iiri··

.1è-.;elae·· ..··44.·e016
· ·lee .

4
6
i&

-4 ·.
*
14

·sephiel
4.

*PiP eePt> ope Poepe ete.0-Pe.ee 11* 46n ..e 0.e e*" * ¡eS te t: i. o:te

ePe .0e4e
p

11.14.1e*:S *:.:**14e. ..set·t

FP),;#;s#,:;e·tó .0=je p`

Advanced technology
Setting the stage for flat-screen tv

Experimental tubeless color set uses 78,000 light bulbs; converts standard signals with pulse-width modulation

By Satoshi Shinnada
Sony Corp., Tokyo

A television receiver with 78,000 light bulbs, 260 sot's, 4,000 transistors, and apower supply that delivers 300 amperes at 30 volts can hardly be called ready for home use. But the only way of discovering the kind of problems that would crop up in developing asmall flat-screen color receiver was for Sony to build the giant 8-foot-diagonal set.
The color tv receiver has its 78,000 lamps in an x-y matrix-300 in each of 260 lines. The most important innovation in the system is the conversion of standard video signals into pulses for digitally scanning the x-y matrix with pulse-width modulated signals.
The receiving circuits use a standard color tv tuner that picks up broadcast signals and delivers the red, green, and blue color signals that normally drive the electron guns in the color tv tube. Three video amplifier channels then deliver the three signals to the horizontal video driver blocks.
These blocks convert the color signals into pwm signals for driving the lamps. The bulbs are staggered from line to line and each bulb is part of two color trios; each trio forms atriangle over two lines. Thus 600 pwm channels (200 color-trio channels) are connected to the 600 lead wires of the video panel.
The bigger they are ...
Many engineers have completed prototypes of smaller displays, ranging from perhaps 12 X 24 elements, or 20 >< 20. But the circuitry for these is far simpler than that for full-scale displays: there are no problems of high current, mistriggering, and sync or signal regeneration, and it's not difficult to delay either sync or video signals through asmall number of steps in a line with a relatively short delay.
Closeup. Sony's color video panel, left, uses incandescent lamps with filter caps for the red-green-blue color trios.

In the color video panel, the vertical and horizontal conductors cross in amatrix. At each crossing is apicture element--a lamp and adiode connected in series. The diode keeps a signal current injected into acrossing from dividing and flowing into any other crossing.
Ironically, tungsten lamps will yield a good picture only with a tricolor scheme; satisfactory black-and-white reproduction with bare lamps is impossible. When tungsten lamps are dimmed, their temperature declines and their light becomes reddish. Lens-cap filters limit transmitted light to red, green or blue wavelengths and make it possible to reproduce white or gray.
Sharp, but not smooth
The 78,000 ordinary tungsten pilot lights form 26,000 red-green-blue trios. Though this is less than 1/10 the number of elements on aconventional color tube, the picture resolution isn't hurt as much as one might think. In the x-y video panel, completely independent information is injected into each light bulb. In apicture tube, the electron-beam spot is ordinarily large enough to cover three or four of the holes.in the shadow mask. Furthermore, in the tube, reproduction of areas with white-peak brightness is hurt by increases in spot size, which cause the phenomenon known as blooming. However, blooming can't occur in the color video panel, because each bulb gets information independently from its neighbors. This keeps the picture surprisingly sharp.
Another advantage over the tube is that colors can't be misregistered. In the tube, beams are aimed at colors and may misland or misconverge. But in the video panel, signals are fed directly to colors and thus always stay in proper relationship.
On the other hand, the picture produced by the panel's 26,000 trios isn't as smooth as that of the picture tube, which has about 350,000 elements.
Interlaced scan can't be used, because there are only 260 horizontal lines. However, non-interlaced

Electronics April 15, 1968

93

Getting the whole picture
Sony's color video panel uses light bulbs arranged in a matrix with 260 horizontal lines of 300 lamps each. The lines are staggered to form red-green-blue color trios spanning two lines.
A television signal is picked up by astandard receiver and the three color signals are separated from the audio and synchronization signals.
The color signals are sampled in the XS blocks, which generate pulse-width modulated signals with a constant amplitude but a width proportional to the intensity of each color signal.
For zero intensity (black), the pulses have zero width. For maximum intensity, the pulses are about 100 microseconds wide. The eye integrates the light and perceives lamps that stay on longer as being brighter than lamps on for less time.
The sampling pulses are taken from adelay line and gated by signals from the 2T11 switch (bottom center), which keeps the sampling pulses in proper synchronization.
The vertical synchronization pulses start the display at the top. The horizontal lines are turned on, one at atime, by SCR'S connected to each line. An eight-phase generator applies power to the sCR anodes. An SCR turns on when the pulse is applied to its gate, either through the YP y-line pulser multivibrator circuits or through another SCR directly above it. The horizontal lines stay on for twice the horizontal scan time.
The eight-phase generator is needed to turn the pairs of lines on in succession and to turn the SCR'S off by disconnecting their anode supply. With eight phases the safes have enough time to dissipate their stored charge before they are to be turned on again. If fewer phases were used, the off times might not be long enough to allow the charges to dissipate, and the SCR might turn on again when the anode supply was reconnected without waiting for the proper gating signal.

YP 1 YP 3
YP 5

SCR

YP 1 YP +1

1111111 1.-1
uIuuI
j+1

(

)ANTENNA

[REMOTE-CONTROL UNIT1
AUDIO CIRCUITS

1COLOR RECEIVING CIRCUITS

Y

2T H MULTI.

2TH

TH

1H

`,1
VERTICAL TRIGGERRESETTING MULTI

V

260
8 PHASE GENERATOR
---t_ D-c SOURCE -- 30 v 300 AMP

SYNC. SEP
L__ _

VERT. OSC.

Y- POSITIONING DELAYED MULTI.

X- POSITIONING DELAYED MULTI

2.TH SWITCH

in:

SAMPLING PULSE GENERATOR

iL
H TH H -

94

Electronics IApril 15, 1968

X1

62

·

63

4 · · X4

X5

66

Xe

X9

· 011 ·

·

· ·

I.· · ·

·

· ·

· · · ·

· 0·· · · 1· ·
· 0··

Xi_1 Xi Xi."
·
Ile! ·
· ·

x 2m-2 X 2m-( x 2m

·

Y1

· Y2

Ote Y3

Y4

Y5
· Y6

·

· '

11

· O'

·

· 'j+1

Ic,.le:), · ··· i el

· · .

sc.: ·.: 40"Y60) Pp

xp

XP

XP

XP

XP

XP

XP

XP

XP

2

4

6

8

·

ix, H-P1
XP
I
a

XP 2m

XP

XP

2m

2m

ITITIT.IIT

-.1 1..------- 0 088gsec --0. AMP - - --or AMP - -Jff--.. - - -0.
7 --. --r· III

Tiz

scan can provide reception that's satisfactory even though it isn't up to normal standards. Non-interlaced scan is used in the small Sony video tape recorder designed for home use.
Time to get samples
Tlie video signal must be sampled to convert it to the multichannel signals required to drive the color video panel. With 300 lamps in each horizontal line, picture information from the original signal for any one lamp must be sampled within an interval less than 1/300 times the horizontal period of 63.5 microseconds, or about 0.2 itsec. The sampling interval is thus 0.05 to 0.1 µsec.
Sampling pulses are supplied to each pwm block through alumped constant L-C delay line with individual sections consisting of a series inductance of 5.6 microhenries and ashunt capacitor of 1,400 picofarads. The delay time of each step is 52.5 itsee divided by 600 channels, or 0.088 psec.
After every 24 channel delay steps, adelay of 2.1 itsec, an amplifier was inserted.
The pulses would survive without amplification for aslightly larger number of delays--although 48 would probably be too many. However, since there are repeating cycles of three colors and individual x lines are connected to alternate y lines, it's desirable to choose anumber divisible by both two and three. The size of the x-output transistors makes it convenient to line up about 24 xdrive-circuits on a single printed-circuit board. If pulses are regener-

ated between the output of one board and the input of the next, then all boards can be identical.
A steady gain
The pwm signal can be obtained with simple circuits. The amplifiers are saturating transistor switches that are either in saturation or off, so that gain doesn't vary between channels. Because amplifier output efficiency approaches 100% and collector dissipation is low, there is agood chance that circuits can be integrated.
With the color video panel, the pulse repetition frequency is half the horizontal frequency, or 15.75/2 equals 7.88 kilohertz. The signal varies from zero to maximum amplitude, and for black the pulses have zero width--no current flows in the lamps. Lamp voltage is constant, and the longer the bulb is on the brighter the image appears to the eye, which integrates the light to create the sensation of intensity.
With pwm, each picture element's duty cycle is 600 times better than it would be if each element were turned on and off befort the next one on the line; the same brightness can be produced with less power.
For example, if an on-off scan was used in a260 by 300 clement array, each element would operate on a1/260 X 300, or 1/78,000, duty cycle. But with pwm, the duty cycle is increased 2 X 300 times, making it 1/130, or 600 times better. In comparison, television tubes have a duty cycle of 1/350,000,

PULSE--WIDTH MODULATOR -CONVERTER

HORIZONTAL SCAN TH' 63.5 µsec - --·-

VIDEO SIGNAL

7
000 0 0 0000 00 0000

HOR. OSC.

r -

o

"2

o

Y3

o

-E7/ 1111[

SW y

Yi

o
:116.7µsec

o o

o VERTICAL SCAN

Yn

X ¡

Xm

VERT. OSC.

XY- MATRIX DISPLAY

Cross at the light. A basic lamp matrix is driven by horizontal and vertical line switches. The diode in series with the lamp prevents the current from taking sneak paths through other lamps.

96

Electronics April 15, 1968

Wide smile. The color video panel, shown with its power supply, right, moesures about five by six feet. The message displayed at the top of the screen is generated through aseparate channel.

since each picture element is turned on and off in succession.
In the practical circuit configuration for the pwm sampling and holding method, for each xchannel there are six semiconductor devices--five transistors and one diode. This isn't a large number of components if circuits are to be integrated. The number of circuit blocks needed is twice the number of lamps on aline, or 600
Because of the arrangement with 600 sample and hold units, sampling fer agiven xline is done only once for every second y line, so that sampling is done only at every second pulse.
The amplitude samples are converted into ramps, whose amplitude is proportional to that of the original. Ramp basewidth is also proportional to the original amplitude. 13> slicing the ramps near the base line, apwm signal proportional to the original amplitude is recovered. These varying-width signals drive the lamps.
The lamp current isn't constant while the pulse is applied. Lamp voltage, as noted, is constant. The lamp current varies during the 10 áusec or so that it takes for the lamp to raach steady state, but then is approximately constant. After the lamp is turned

off, brightness Fades rapidly, but afaint afterglow continues for several milliseconds. Light output falls to zero, though, before the end of the frame, which lasts 16.7 msec.
These rise and decay characteristics are nonlinear, and are different for each color. If uncorrected, these differences would unbalance the color signals. Correction is applied by simple curve-shaping circuits with diodes to give segment approximation of desired characteristics in the three video amplifiers. Circuits of this type have long been used in analog computers as curve generators, and in television cameras for gamma correction.
Easy work
The lamps for red have ad-c rating of 2.0 volts and 30 milliamperes. Lamps used for green have a d-c rating of 1.5 volts and 30 ma. Lamps used for blue have ad-c rating of 1.5 volts and 70 ma. However, the lamps aren't used at their rated current and voltage levels.
The lamps are operated only for amaximum duty cycle of 0.7%--at 30 volts for 100 iisec maximum out of each 16.7 p.sec. The peak current for the red lamps is 400 ma, for the green lamps 600 ma, and

Electronics 'April 15, 1968

97

Nearly afarad. The power-supply filter uses 100 capacitors of 8,000 mircrofarads
each for atotal of 0.8 farad.

411j
P,14041,1
· 411,1 r4
IY0,1).1
iY11 11,41 il eit44111
',111.1011
;4lrie$Isi
ÀoirYIY
4114,44
1pjl
i14,14.41
0.1

Pulse source. The pulse-width modulator is built around dipped hybrid integrated circuits, center.

Side view. The color video panel has drive circuits at the rear and around the edges.

peak current for the blue lamps is 1,000 ma.

Each output transistor in the x channels is oper-

ated at aduty cycle of 0to 75%. These transistors

are operated in the pwm mode at aperiod of twice

the horizontal-line time, or nTil,with the peak cur-

rents of the lamps. For this type of operation, the

dissipation of 11

.,ut transistors in the various

channels nu it die range of 100 to 300 milliwatts.

Neither the current value nor dissipation is much

of aproblem; the output transistors in the xchan-

nels are operated without heat sinks.

Enter the SCRs

For yline switching there are nswitches, which go on and off in succession with overlapping ontimes of TH,and with total on-time of 2TH.The entire process repeats at intervals with aperiod of Tv,which is 1/60 second.

However, unlike the x-line switches, the y-line switch must handle high values of pulse current. For each line the maximum pulse current equals the sum of the current flowing into 300 crosspoints--
(0.4 4- 0.6 1.0) amp X 300 channels/3 is 200 amps peak.
Since this pulse current flows with a maximum duty ratio of 0.7% for high light white raster during
arepetitive period of Tv = 16.7 msec, the time average value of current and the loss in the switching devices aren't excessive. But pnp or npn devices rated for handling the 200-amp peak current aren't available. One could get by with perhaps five to 10 power transistors in parallel for each line, but for asystem with 260 lines this means it would be necessary to use something like 1,300 to 2,600 power transistors--and there isn't really room to fit them all in. Space and cost would be terrible, and besides

98

Electronics April 15, 1968

TH

INPU rvInioSIGNAL
E"

t._T

TH

-am

ti -DELAYED SAMPLING PULSE

.- Tpwp4 --e. -···

··-Tpwt4

-. T.pwig

o-'.-. HOR.SYNC

BRIGHT

DARK

s

Lt MEDIUM

HOR .SYNC

HOR SYNC

PWM OPERATION

Just a sample. The sampling pulses produce pwm signals
corresponding to the video signal amplitudes.

this abrute-force way of attacking the problem. Switching 200 amps on the yline requires ade-
vice with extremely low saturation resistance--such
as asilicon-controlled rectifier. The SCR can turn on with very small trigger
power. However, there isn't any good way to turn it
off without turning off the d-c power supply connected to their anode circuit. Therefore, an additional power switching circuit must be connected between each scat and the d-e power supply. The
power switching circuit consists of a multiphase square-wave generator with at least two phases--in this circuit, eight phases are used.
After the anode powe: supply has been turned off, there may be trouble when it is turned on again; because of stored charges, current may start to flow

even though no gate pulse has been applied to the

SCH. It is thus necessary to increase the number of

phases of the power supply, and keep the device off

long enough so that the stored charges have enough

time to dissipate.

The prototype video color panel has an eight-

channel, eight-phase power pulse generator for currcnt switching. Each phase has a pulse width of

2TH,and, repeats with aperiod of 8TH,so that the

SCR'S are held off phases are shifted

for from

atbheoiurtne3i8g0hbooercs.byInpdrievciidsueally

TH.

Alternate ylines are triggered by amultivibrator delay train. The line is turned on, and ad-c trigger

signal is also applied from this line to the following

yline. The second ysat cannot trigger, though, be-

cause voltage has not yet been applied from the

eight-phase power supply. Thus, only atotal of 130

multivibrators are needed. Multivibrators are syn-

chronized by pulses with a period of twice the

horizontal scan time, 2TH. At precisely the correct time for the start of ay

line, voltage is applied, the SCR turns on, and the x-

line transistors start injecting power into the xlines.

Adjusting the picture

When ayline switches on, the load is the current in xtonly; the load then increases, until at atime TH later it reaches the peak--a maximum of 200 amps. The load then declines until at atime 2TH after yi was first switched, it has fallen to about zero. The waveform is thus a symmetrical triangular pulse.
During this period the next yswitches on and adds to the power supply load. Currents in the two adjacent ylines overlap with ashift of TH.
Among the x;pwm waveforms are those with a
pulse width that exceeds one TH and those that have apulse width of 100 psec. These occur at the white-peak points in the picture. Taking these circumstances into consideration, the engineers de-

PW M VIDEO SIGNAL

u-
VIDEO SAMPLING

X2

X3

X4

X5

I I I

EL

x,,,
LE

TM

SAM PLING PULSE
TM
ll
I -DELAYED PULSE

T TT
t DELAY LINE
_

Delay pulse. The sampling pulses are delayed for each column of lamps and the pulse-width modulated signals thus turn on the lamps in succession across a horizontal line.

Electronics IApril 15, 1968

99

Plug-ins. Lamps are inserted in blocks for final assembly. However, since lamp ratings are different, red, green and blue lamps are not interchangeable.
signed the power supply for the entire color video panel to be able to supply aload of 30 volts at 300 amps, or about 10 kva maximum. For d-c smoothing of the power line, 100 individual capacitors of 8,000 microfarads each--totalling 0.8 farads--are arranged on the rear of the panel behind the lamps. One must also provide for correctly centering the reproduced picture. To do this, an adjustable x-positioning multivibrator delay is inserted between the horizontal synchronizing oscillator and the sampling-pulse generator.
In the same manner, ay-positioning multivibrator delay is needed for vertical centering. Furthermore, it is necessary to finely adjust the starting point of the first ychannel so that the delayed vertical synchronizing pulse coincides precisely with the horizontal synchronous position.
A hope for the future
Anyone who has had experience with tungsten filament light sources might worry that the lamp's light decays too slowly for this application. But this isn't aproblem with the miniature lamps of the type used for dial lights. Luminance decay of these lamps is sufficiently short compared with the 16.7 msec vertical scanning period of the television signal, because small filaments cool quickly.
Of course, one hope for future display panels is ap-n light-emitting junction. If an electroluminescent diode could now be produced more cheaply

than the lamp plus a diode, perhaps by Ls' techniques, and made to produce the desired red-greenblue trio, then there would be no need for tungsten filament lamps. But today's diodes aren't bright enough, and blue luminescent diodes can't yet be produced. Also, costs are high and yields poor.
The light could also be obtained from agas discharge, and the diodes would then become unnecessary. When three glow tubes are connected in series, there will be no discharge unless three times the single tube-exciting voltage is applied to the series connection. To bypass the desired crosspoint, the current flowing between the two driving lines must flow through at least three other crosspoints.
Because of the gas tube characteristic, approximately three times the voltage required to break down one lamp is required to break down three in series. Because of this inherent selection mechanism, avoltage slightly more than sufficient to break down one lamp will result in breakdown, or glow, of the lamp at the crosspoint, and no current will flow through sneak paths. The first studies actually were with aneon lamp matrix panel--a local part of the red matrix with only 40 X 50, or 2,000, elements was operated successfully before the neons were eliminated in favor of the incandescents. But, still, aflat-package gas tube may eventually be practical, using phosphors to achieve the different colors.
The human eye is rather tolerant of chromaticity errors in the blue region. This is fortunate, because radiation in the blue region is low for tungsten filament lamps. A cyanic-blue filter cap is used on the blue lamps to pass the emitted blue light. This allows the operating current to be held low and keeps lamp life at the same high level as that of the other color lamps. Green with good color saturation can be obtained with the green filter.
Problems, problems
The color video panel still has problems of uniformity, cost, life, and applications.
Display uniformity is poor compared with that of aconventional picture tube. The random dot-bydot nonuniformity caused by variations in the brightness of individual lamps can be eliminated for practical purposes by tightening the lamp specifications, but this isn't the worst problem.
Variations among the drive levels of xior yichannels cause "stripes" that resemble the runs in nylon stockings. With pwm operation, the variations among channels caused by differences among the transistors become small enough to neglect. But this method of operation doesn't eliminate variations caused by differences among capacitors and resistors, and there is agreat need for much tighter specifications to eliminate these errors.
The system is also expensive. The color video panel has 260 SCR'S, 180 power transistors, 1,500 medium-power transistors, 2,500 small plastic-package transistors--mostly in hybrid integrated circuits --and 1,000 small diodes, also mostly in hybrid integrated circuits. And it has the healthy appetite for as much as 10 kva.

100

Electronics April 15, 1968

SAMPLING PULSE

ON

FROM DELAY LINE

1T22

ON

FROM 2T H

10vpp SWITCHING

VIDEO (INVERTED)

24v

Ik(BLUE) 2k (RED,GREEN )

PVIM OUTPUT TO X LAMP

Sample and pulse. The sampling and pulse-width modulation of the video signal is done with the combin3tion of transistors Qi and Q. The three transistors to the right amplify the pulse-width modulated signals.

Money, money
The lamps and diodes and cross-grid construction into which they are plugged for display account for about 75% of the total materials cost. The semiconductors in the circuit account for about 10% of the materials cost, and other circuit components the remaining 15%. If this system were to be made into acommercial product in its present form, it would have to cost about 100 times more than aconventional color tv set. On the other hand, it would cost about the same as a color display of comparable size using projection methods, and the projection display can be viewed in alighted room.
An early doubt regarding the 100-inch color video panel was: would the life of the bulbs be so short that the filaments would be continually burning out? Even at low temperatures, when the light from the bulbs appears reddish, it's possible to obtain enough blue light with the proper color filters. Lamps with high current ratings were therefore chosen, and the input power was increased. Since the lamps are rich in red wavelengths, red current levels are lowest. Green is alittle higher and blue lamps are driven the hardest. The system has an average lamp life of 5,000 hours.
But with a total of 78,000 lamps, if lifetime is homogeneous so that at 5,000 hours half are burned out, then at 10 hours 80 lamps (about 0.1% ), at 100 hours 800 lamps (1%), and at 1,000 hours 8,000 lamps (10%) will probably burn out. This might mean that every few minutes one will have to change alamp.
On the other hand, if lamp life doesn't vary the color video panel would operate without incident for 5,000 hours.
The distribution of life among lamps isn't known. But as long as the lamps burn out in random positions the effect isn't serious. A more serious problem is that some of the lamps are far brighter than their neighbors and stand out as prominent points. But dark points where lamps have burned out are like very small freckles, and are much less noticeable

than one might think--like aspeck of dust on the face of aconventional picture tube.
For practical purposes one can neglect burnedout lamps until their number reaches about 1% of the total, and then replace all the defective ones at once. With the lamps now used, this must be done after about 200 to 300 hours of operation. The ability to operate this long between regular maintenance periods means that the system is suitable in this respect for practical applications.
Putting it to use
There are many closed-circuit television applications for which this display could be teamed with a color video tape recorder or color television camera. When considering applications for the color video panel, one must remember an extremely important characteristic: when a raster sweep is used on a conventional picture tube, both horizontal and vertical retrace time is needed. It isn't normally possible to use these intervals for display.
With the color video panel, non-retrace-time scanning is feasible, and it's relatively simply to display completely independent information--such as alphanumeric characters--that are derived from separate sources. In this display, the horizontal retrace interval isn't put to use, but the photo on page 97 shows acharacter display, picked up by aconventional tv camera, inserted above the picture display during the vertical retrace interval.

The author

Satoshi Shimada is manager of advanced tv technology--display
and cameras--in the development division at Sony. A 1953
graduate of the Tokyo Institute of Technology, Shimada joined
Sony in 1959 and developed the company's first 8-inch
transistorized tv receiver. He also developed Sony's 5-inch micro tv, which went on the market in 1962.

Electronics April 15, 1968

101

ileEZZCZWIMCZUMMMUMMINNOWNWM

aI-m-liNNyrnmnrmmmaoNulmumm-.mnm.fcro-oernNrmmamrmNeeuntmominmoNormmo-w-nnmmim-ommm7rnemmi?mAmvnNoicrsmi.?mom-onwnmimm-m-memmn.ooomrrimt-mmv.uoerfwcufvamliNNvuw

Whatever your recording needs--from magnetic tape to oscillography--you will find described here precisely the "right" instrument to meet them. Compare their respective advantages with those of any competitive recorders, and you will also discover why CEC continues to be the recognized leader in data instrumentation.
In addition, CEC also markets acomplete line of accessories and signal conditioners.

·All-Electric Tension Control. Solid-state amplifiers for improved linear tension control and greater reliability.
·15-inch reel capacity.
·Automatic 8-speed transport with electrically selectable electronics.
· Phase-lock capstan control electronics included for improved speed accuracy.
·Convertible from wideband to midband recording. New plug-in heads offer easy interchange of headstacks up to 42channel capacity.

VR 3300 Recorder/Reproducer--Un-

VR 5000 Recorder/Reproducer--CEC's

matched for applications where ruggedness and mobility must be combined with

most advanced new recorder, the VR 5000 outstanding performance

, has established two important break-

throughs. 1. A maximum

r`

·100 cps to 300 KHz

time base error of ±-400
nanoseconds at 120 ips. Because of this improvement in time base error, the

k Co"
II
keo..

direct frequency response; dc to 20 KHz FM frequency response.
·Dual capstan drive sys-

ultimate in real-time resto-

tem provides closed-loop

ration of data is now pos-

speed and tension con-

sible. And tapes made on

trol equal to standard laboratory systems.

data acquisition recorders under severe environmental conditions can be successfully reduced with correct time base restored. 2. A flutter correction

· Interchangeable record and reproduce electronics and heads with GEC's VL 2810 Continuous Loop Recorder/Reproducer.
·Six-speed record/reproduce system.

capability five times more efficient than

that of the next best recorder available today. Consequently, the VR 5000 is the only recorder that offers Dual Inertia, or the ability to translate the ideal system concept into aworking reality--high mass recording and low mass reproduce.

VR 3700 Recorder/ Reproducer--This re-
corder has special CEC magnetic heads which extend its frequency range to 2.0 MHz--plus 500 KHz for FM--at the traditional cost of a1.5 MHz unit.

·Unequaled phase lock range.

The first and only 2.0 MHz

·Close Loop Drive without pinch rollers.
·Positive Air Pressure (Patent Pending) tape loop for reel perturbation isolation eliminates vacuum bin problems.
·Bi -Directional electrically switched 7speed drive provides the fastest start/ stop times available on any instrumentation transport.
· Tape speed accuracy of ±..05% with tape servo, machine-to-machine.
·Air Guides eliminate rotating elements in tape path.

laboratory recorder that combines versatility and reliability at abudget price.
·Magnetic recording heads guaranteed to exceed 1000 hours. CEC's unique, solid metal pole-tip design has eliminated the inherent deficiencies of lamination and rotary head design.
· Failsafe DC Capstan Drive assures dramatically-improved flutter and TDE performance.

VR 3400 Recorder/Reproducer --Identical in specifications to the VR 3700 transport but with midband electronics. However, should eventual data handling requirements call for a2.0 MHz response, the VR 3400 may be converted to aVR 3700 by a simple exchange of heads and electronics. This modestlypriced recorder will readily meet the vast majority of laboratory requirements.
Type 5-133 Recording Oscillograph-- This versatile oscillograph is essentially two instruments in one. Reason: the 5-133 utilizes two galvanometer magnet assembl ies.The galvo recording lamp intensity is individually controlled so as to permit recording from either magnet assembly, or both, as desired. Two data setups can be made at one time and recorded simultaneously, or be made alternately and recorded sequentially utilizing full chart width for each. The 5-133 is available in 12-, 24-, 36-, and 52-channel configurations. There are 5 recording modes -- 3 direct-writing and 2 developout. And being of modular design, the unit is readily adaptable to additional or future instrumentation.

102

Electronics April 15, 1968

,VAMMAMINVMUMMUT . ''' ''''''' '' '''' "MUMNAMMOMMUMNIONAMINNMAIMOMVIAMOMMIM

.r,Nc,nra,o.T,rr,ono,nEl,nmu,·Nr,ovm,vo,ion,rrt,up-,c--n,ure,rwnt,fcnrrortonN-NotNomcve+ripo.nnn:ifo·cum--os--nrD.roirrmononrooPomtur-eotnmrieath,i.:me1rru1--iv1N.r6omi3.on4.ma1fi`·ftu4lut1otn0cirTet--Cn-InrrAmcoIenrtoiesrnorurta.oNt0tri0rr]rii.uyr.ci--0caN1ilNmn-ranmCvreIunrNonnNotorontnlra,v--cmintonmlmrc---crPmrhuoufnrnimocrraorcrirnerclnuIio,NeemNunrIci--ticnlearaN-tncrtaaolme--rruMmonOmmrrn-.cinpinr.ntnojmctneosoerrlcntroaht-sIer--Nror.nre0rr0cc--rvuevnuarNnrnmmereaonztsiun---unnimonn

Type 5-124 Recording Oscillograph --

Shown with the DataFlash Takeup Acces-

sory which requires only 1 second to

readout, the 5-124 has become a new

"must" for industry. Portable, easy to

operate, this instrument offers big re-

corder capability in asmall-size, low-cost

package. The 5-124 provides up to 18-

channel print-out recording, and record-

drive systems with options from 0.25 ipm

to 128 ips.

·

Type 5-126 Recording Oscillograph--The new "best buy" in oscillography. At a price hundreds of dollars less than any comparable instrument, the 5-126 offers the basic capabilities of a light beam oscillograph at acost approaching that of a direct writing recorder. With CEC's 7-380 Galvanometer, this portable unit will record from dc to 1KHz. Its tungsten light source assures optimum trace quality and lamp light, minimum cost and maintenance, instant operation with complete safety. Nine channels produce vivid data traces on 7-inch-wide paper. Records by direct print-out upon exposure to ambient light, thus eliminating the need for chemical processing. And, due to CEC's simplified front-loading system, no spooling or threading of paper is required.
·
Type 5-119 Recording Oscillograph--A truly universal oscillograph, the 5-119 has become a popular, proven performer for

laboratory, mobile, airborne and marine use. Both dc and ac powered models are available.The 5-119 accepts all three types of record magazines, DATAF LASH ®, DATARITEO, and conventional, making it possible to utilize every known photographic technique on either the 36- or 50-trace models.
Type DG 5510 Thermal Writing Recorder --This 8-channel recorder brings asignificant advance in performance and reliability to direct-writing oscillography. The basic 5-510 recorder is a self-contained instrument with driver amplifiers and power supply capable of accepting awide range of highlevel input signals. Interchangeable plug-in attenuator/preamplifiers are available to further extend the input range. It employs aheated writing stylus to deliver sharp contrast rectilinear traces on CEC's DATATRACE® ThermalSensitive Paper. Other outstanding features include: Solidstate electronics ·Immediate readout · Superior frequency response ·Calibrated zero suppression · Cabinet mounting, including dolly for complete mobility.
Type DG 5000 Recording System -- new from CEC -- is an assembly of standard product building blocks systemized into a complete configuration, thus providing overall capability from transducer to display. Since the DG 5000 will accept any

CEC oscillograph, or any of the acces-

sories, it may be tailor-made to virtually

any configuration--or economically ex-

panded to meet future

configuration require-

ments. This fully flex-

ible system will deliver

up to 52 recording

channels with light-

bearr galvanometers

or 8channels for

thermal writing. Appli-

cations include industry,

aerospace and medical

science, or any opera-

tion calling for the

44 011 acquisition and precise

111

4 measurement of dynamic or static data.

Type DG 5511 Thermal Writing Recorder --CEC's unique, solid-state DG 5511--the first low-cost, portable direct-writing recorder--provides capabilities formerly achieved only through multiple instru-
ments. Plug-in signal conditioners are available to accommodate a wide range of voltage inputs. No preamp is needed for high-
level signals. Converts
from high-level inputs by asimple change
of plug-in attenuator/amplifier units. The DG 5511 combines ease of operation with ahigh degree of resolution on heatsensitive paper.
For full information about these products, call your nearest CEC Field Office, or write Consolidated Electrodynamics, Pasadena, California 91109. A subsidiary of Bell &Howell. Bulletin Kit 1712-X3.
CEC DATA 1115TRUFFIEFITS

BELLEiHOWELL

Electronics April 15, 1968

Circle 103 on reader service card

103

Circuit design
Designer's casebook

Designer's casebook is aregular feature in Electronics. Readers are invited to submit novel circuit ideas, packaging schemes, or other unusual solutions to design problems. Descriptions should be
short. We'll pay $50 for each item published.

Gate-to-source resistor

stabilizes FET regulator

2N3686

By Bill Birnbaum
Industrial Scientific Research, Orange, Calif.

D-C SUPPLY

LOAD

Field effect transistors, like the old vacuum-tube
pentodes, are used to make d-c power supplies constant-current sources. Connected in series between the load and the supply, the FET will, when there's no gate voltage, maintain aconstant current through the load despite changes in the supply voltage.
But where the FET is biased by the direct connec-
tion of gate to source, wide temperature variations can cause changes in the FET'S drain-to-source resistance and drastically alter current flow.
In such cases, aresistor can be placed between the source and gate connection. With this configuration, changes in the resistor's voltage drop caused by swings in drain-to-source current de-

MICROAMPERES 1400 1200
F- 1000
800
o ' 400

T.-65°C
T.+25°C T.+125°C

velop a bias on the FET that holds the current steady. Current through the FET--the same current that flows in the load--is thus affected by both temperature and gate voltage, as expressed by the equation:

MDs = AIDST F aDSG

where Ii,, is the total change in drain-to-source

currents,

is that change caused by temperature,

and IDsc the change attributable to gate voltage.

When the drain-to-source current's relationship

with the gate voltage, Ipsc,

VGs, is inserted

in the equation, the result is:

'Ds == InsT 1 gmVGs

Since VGs =

RI--with the negative sign

indicating that an increase in drain voltage makes

the gate more negative--the equation can now be

written in terms of I'm and 'DST.

IDS = IDST

gmIDSR1.·

After transposing, it becomes

IDS T

200

20

40

GATE-TO-SOURCE VOLTAGE (V DG )

60v

This equation indicates how R1 and the transistor's g,,, minimize the effect atemperature change has on the drain-to-source current.
The larger the resistor, the greater the regulating effect, but too large a value limits the current in
the transistor to afew microamps, lowers the device's avalanche breakdown, and thereby narrows the range of d-c supplies the FET can regulate.

104

Electronics April 15, 1968

Power transistor's r-f gain measured by brief pulse
By Octavius Pitzalis Jr.
U.S. Army Electronics Command, Fort Monmouth, N.J.
The frequency at which apower transistor's gainbandwidth product becomes unity is calculated from acurrent-gain measurement made at alower frequency. If the calculated frequency, commonly called fT,is to be meaningful, the measured current gain should be made `'hile the transistor is operating at its recommended current and voltage levels. Unfortunately, the power dissipated at these levels raises a transistor's temperature to a point where leakage currents multiply and internal resistances increase. These changes make it impossible to measure, with any accuracy, such adelicate parameter as the transistor's current gain.
By pulsing d-c currents and voltages into the transistor for a few microseconds and measuring the current gain during this interval, high temperature and its adverse effects are prevented from

HEWLET - -- PACKARD

MODEL 132 A OSCILLOSCOPE

V:C

R-F OSCILLA -OR
PULSE GENERA 'OR

VOLTAGE PROBE

4 7
1,000pf 47
HP 1110 A CURRENT PROBE

C4 1,500 pf

1 ,..r--. 2uf

1

___I_ '

=...

C2 --_-:-.

170-78 Cpf

0.15h

--

IF--

3900p.f

.--1(--. C3
500pf

HP 1110 A

CURRENT

PROBE

L2

Ql

HEWLETT -PACKARD MODEL 132 A OSCILLOSCOPE

CHANNEL A INPUT
o

CHANNEL B INPUT
o

Electronics April 15, 1968

105

causing any detectable measurement error.
A 35-megahertz signal is coupled from the r-f oscillator through capacitor, CI,into the base of the transistor. It is not amplified, however, until one of the 10-microsecond pulses, supplied every millisecond by the pulse generator, biases Q1 into
conduction. When the momentary amplification takes place the resultant signal is shorted to ground through the series resonant circuit consisting of C., C3 and L.. The inductance L. is a 3/4-inch length of #16 bus wire insulated so that no shorting takes place with the probe clipped on. This short, the required output for acurrent-gain meas-
urement, can be adjusted for any frequency by varying C.. The inductance, L1,prevents r-f currents from entering the d-c supply. Its voltage drop and any others that might occur during the pulse are overcome by the charge that exists on capacitor, C4. Monitoring the collector voltage and cur-
rent is, nevertheless, necessary and is best done

with a voltage probe, a dual-beam scope and a current probe.
When collector current, L, and base current, ib,are measured on that portion of the frequencygain curve when the gain is dropping 6db/octave the following relationship is valid:
fT = f li
where fT = frequency at which the transistor's gain-bandwidth product is unity
i,, = a-c collector current a-c base current
f= frequency at which L. and ib are measured
The two current measurements are made with a dual-beam oscilloscope and the frequency of the input signal is read directly on the oscillator's dial.

Amplifier flattens ripple in d-c regulator
By Irvin Budych
Borg Instruments, Delavan, Wisc.
Ripple in the output of arectifier that uses acapacitive input filter can be removed by a simple and inexpensive transistor amplifier. By taking aportion of the input ripple voltage, and amplifying it with

atransistor, an inverted collector signal is obtained.
Adding this signal to the ripple voltage neutralizes the input and the amplifier reduces any variations in the output to zero. It is as effective in choking ripple as alarge inductor and yet does not lower the high output voltage of the capacitive filter.
The small signal needed for neutralization is taken off the line through CI and fed into ahigh impedance circuit comprised of R1 and 112.After amplification by Q , the signal--inverted now by the transistor--is coupled through C., onto the reference voltage at the base of Q2.Riding there, it reduces all the ripple in the regulator to zero.

--50v

cl
25/21

82k
Rf
40k

R2 1.8k

15k

C2

2N1175

470

15k

2N2147 3.3k
2N414 1N3031

1N3016 2.7k
4.7k

REGULATOR

106

Electronics lApril 15, 1968

Easily installed, the new Microf.lm Recorder Accessory makes high-quality archival records on inexpensive 35mm film.
Like to cut cost of oscillographic recording up to 95% with asimple microfilm attachment? Here's Honeywell's solution:
tion of the data to be reco -ded, yo Jcan choose the proper method with asimple, three-position switch.
The Model 2400 is easly mourted above arack-mounted Visicorder, and can be factory or field-installed. Film is contained in a plug-in magazine that can be renoved and replaced ir about 10 seconds; ext-a accessory magazines are available.
Fits these Famous Honeywell Visicorders:

8roll, (1500'; Standard recording paper
$280.00

150' of film (equivalent of 1500')
$14.00

A rewarding investment, our new Model 2400 Micro'ilm Recorder Accessory lets you make permanent dynamic records at up to 1/20:h of the cost of using direct-write paper. It will record data on film simuitaneously with your Visicorder oscillograph's paper record, or can be operated so only amicrofilm record is obtained.
You save money, and you save space because microfilm makes for convenient storage and easy access to data for analysis and reference. Viewing and reproduction can be handled by any of a
large number of units currently available.
Better resolution, too! In addition to being economical, the Microfilm Accessory lets you record data at speeds not possible on direct-write ascillographs. When used with our Model 1508 Visicorder, for example, you could record data on the paper record at 120 ips, the 'nstrument's fastest paper speed. At the same time, the Microfilm Accessory could record the identical data at an equivaient paper speed of 320 ips for greater resolution of the data.
For maximum recording versatility, you have three methods of reccrding when your Visicorder is equipped with the Microfilm Accessory: -r icrofilm only, direct-write only, and combined microfilm and direct-write. Depending on the importance and/or dura-

Electronics April 15, 1968

11
O r F- -tries ei>" I

r=om

NIC

Model 1612

Model 1912 (Shown with Microfilm Accessory)

Model 1508

Available for immediate delivery, the Microfilm Recorder Acces-

sory is another example of how Honeywell's broad line. backed by

local sales and service, can provide the precise solution to your

instrumerta lion problems. For full details, call Mr. Don Anderson

(collect) at: (303) 771-4700, or write: Honeywell, Test Instru-

ments Division, P.O. Box 5227 Denver, Colorado 80217.

Honeywell

Honeywell engineers sell solutions

Circle 107 on reader service ca -ri

107

Design theory
Narrowing the margin of error

Common-mode dev:ations that alter the outputs of data amplifiers can be minimized by combining inverting and noninverting op amps

By Robert I. Demrow
Analog Devices Inc., Cambridge, Mass.

Engineers designing with differential operational amplifiers must continually reckon with commonmode error--a part of the difference in the voltage at the two input terminals that introduces discrepandes into the output. 1f they don't make allowances for the problem or act to minimize it, all calculations and measurements will be faulty.
An ideal differential amplifier with two input voltages, eA and ee,should respond only to the difference between them, e,,. Thus,
--e.. (eA -- ('lt) = A
where A is the amplifier's open-loop voltage gain, and e,, is the output voltage. If eA = 10 volts and
=- 10.002 volts, for example, the effective input is 2 millivolts and the ideal differential amplifier responds only to that signal.
In practice, however, the differential signals are distorted by common-mode error, resulting from a voltage common to both input terminals, a factor usually attributed to imperfections in the input circuit's symmetry. Unequal gains behind the amplifier's inverting and noninverting terminals are one cause, for instance.
A more realistic expression of a differential amplifier's response, therefore, must take into account the degree to which the common-mode voltage is rejected--a factor represented by CNIBR, or commonmode rejection ratio. This practical expression takes the form

fier, common-mode error can vary with frequency or voltage level. A circuit's over-all CNIIIR depends upon the inequality of the amplifier's internal gain, common-mode input resistance, and any deviations from the values calculated for the external resistors.
Joining forces
The error can be minimized by combining inverting and noninverting op-amp circuits to form adifferential amplifier. The inverting type develops a negligible error because the common-mock signal here is in the microvolt-to-millivolt region. However, this circuit provides low input impedance, particularly when wide bandwidths are required, and anoninverting op amp is therefore needed for most applications. This is where common-mock error becomes important.
The differential amplifier combining inverting and noninverting circuits can be used to eliminate ground-loop potentials and can act as abridge amplifier measuring strain, force, pressure, temperature, and other physical variables. A further description of inverting, noninverting, and differential

en =

-- CA -- A + CMeeRIlR

ea

where eem = (eA
Common-mode rejection CNIR is expressed in a logarithmic form:
CMR = 20 log 10 1CMRR The accuracy of differential amplifiers can thus be limited by both A and CNIHR. And in any ampli-

-- IDEAL AMPLIFIER OF GAIN A
Common-mode error. Voltage e.. represents the difference between input voltages e, and eR. The common-mode error, shown as asource in series with en, is proportional to e...

108

I Electronics April 15, 1968

circuits appear in "Amplifying remarks," p. 110. Although the transistors used in an operational
amplifier are elaborately matched and arc gainstabilized by internal feedback, there may nevertheless be again difference between inverting and noninverting channels of one part in 10,000, or 0.01%; this holds even for quite expensive units. Run-of-the-mill field effect transistor op amps have gain mismatches of 0.1% caused by circuit imbalance resulting from the high output conductance of FETS.
But consider an economy amplifier with anominal open-loop gain of 10,000 and again error be-
tween its inverting and noninverting signal channels of one part in 10,000. The noninverting gain might then be 10,000 and the inverting gain only 9,999. If both input terminals are connected to a 10-volt common-mode source, the noninverting terminal creates an output of 10 x 10,000 volts while the inverting produces 10 X 9,999 volts. The net effect is an output of 10(10,000 -- 9,999), or 10 volts. Thus, the common-mode output Vo,,,, can be represented by Ve.(Ao -- A1), which ideally would be zero, but for this amplifier is 10 volts.
The factor (A0 -- A1)is called the common-mode gain, C.,,, because the 10-volt common-mode output can be regarded as having been produced by multiplying the common-mode input voltage, 10 volts,
by this gain: Vo,. = Ve. X G,..

/ INVERTING INPUT GAIN --A 1

IDEAL AMPLIFIER GAIN=I
GAIN +A 2 NONINVERTING INPUT

Vocm-. .. Vs (A2 -- Ai)--
R +R Vo DIFçsF,'. Vs( IR 2 2)
Vo

Vf V (RI-R42-R ? )

S

10-VOLT SOURCE

R2

Sum of the parts

Complete circuits may also exhibit a commonmode gain. Even a circuit with an ideal op amp having identical inverting and noninverting gains can develop acommon-mode error when commonmode voltage is applied in unequal proportions to its inverting and noninverting terminals.
The differential configuration relies on the voltage divider effects R2/(111 + R2)and R4/(R3 4- R4)to apply equal fractions of the common-mode voltage to the inverting and noninverting terminals. If these fractions are identical, no differential component of common-mode voltage is created and the amplifier develops no common-mode output. This, of course, assumes aperfect amplifier in which A1 = A2.
But if off-the-shelf resistors with 0.1% tolerance are used for RI,Ro, Ra, and R4, aresistance error for the worst case may make R4/(R3 ± R4)larger than its theoretical value, and Ro/ (R14- R2)smaller than this same value. There will be anet fraction of common-mode voltage e,,,, applied differentially between the amplifier's input terminals, and this will be amplified by anoninverting gain factor of (R 1 4- R2)/RI to create a common-mode output error proportional to the resistance tolerances.
The worst-case distribution of resistance errors occurs when the four feedback resistors assume new values of R1(1 -- K), 112(1 K), N11 1(1 4- K), and Nlio( 1-- K), where K is the resistor tolerance, and N is the multiplier.
Common-mode rejection ratio is defined as the ratio of closed-loop, or normal-mode, gain, Gm. =
Continued on p. 112

\in Re
COMMON-MODE OUTPUT, VVSAiAI

BUT Vo();:ze.Vs(FOR AreAel) SO \e4VsAiVsAl

'A2-- A1). POSTULATING Vocm=e-M GAIN),

THEN (A2--A 1)=COMMON-MODE GAIN; ALSO,

EQUIVALENT C-M INPUT ERROR BECOMES

e =V Cm Om

WHERE A IS AVERAGE GAIN PA

A,+A
A= 2 =10,000

Vocm=Vs(A--,-A 1)=I0V

ecm= vor =vs( A)-Imv

CMRR

DIFF GAIN C-M GAIN

A A2--A 1

10,000

C-M INPUT
OR -c-m INPUT ERROR VS:VS\ A I )

- A =10 000 A2-- AI

Defining error. Inequality of inverting and noninverting
gains is the basis for common-mode error (top). A common-mode output proportional to gain inequality (center) is represented by adifferential component of common-mode input, e,,,, applied between amplifier's
input terminals (bottom). Value of hypothetical error source, e,,,,, is common-mode voltage divided by CIVIRR.

Electronics IApril 15, 1968

109

Amplifying remarks

CAPACITANCE STRAYS LIMIT BANDWIDTH

There are three amplifier designs the engineer must understand if he is to build functional circuits.
Inverting. This is the best known and probably

TO fc z2irRf

C t:"

the most versatile op amp. Its closed-loop gain, Vs/Vs,

has a value very nearly equal to the negative value

of the ratio of feedback to input resistor, R1/R1.If the op amp's internal, or open-loop, gain is high, say 10,000

volts/volt and upwards, the error voltage, V,, at the

summing junction, S, is very small--less than 1milli-

volt for again of 10,000 volts output. In effect, there-

fore, point S remains within a whisker of ground po-

tential--really at avirtual ground--so that input signal

current Li,is very nearly Vs/R i.More accurately, Isig

is (Vs --

and V. is just afew microvolts.

Because the summing junction is assumed to be at

ground potential, the inverting circuit's input impedance

SIGNAL CURRENT SEES INPUT IMPEDANCE OF APPROXIMATELY RI

is equal to input resistance, 111.

Stray capacitance--rarely less than 1 picofarad--in

parallel with feedback resistance 11.1,limits the circuit's bandwidth to afrequency that makes the leakage reactance 1/274,r, equal to Rr.This bandwidth, restricted toli rC, not only affects frequency but influences gain and input impedance.

fc -2eRfc

GAIN G
1!_s (
RI I+( j2 fc)(R C )

High input impedance requires a large Ri.If the amplifier has to operate at high closed-loop gain, how-

s -r

ever, feedback resistance Rf must be higher than the

input resistance in the ratio, Br gain X 111.If the input impedance has to be 1megohm to avoid source-

loading effects, for instance, and a60-decibel (1,000:1)

closed-loop gain is required, the feedback resistance

becomes 1,000 x 1megohm = 1,000 megohms. The frequency at which the reactance of a 1-pf leakage ca-

OPERATING FREQUENCY

pacitance equals 1,000 megohms is only about 160 hertz, which makes a pretty spectacular bandwidth limitation. Actually, 1,000-megohm high-stability resistors don't exist, so a circuit such as the one at the

STRAY CAPACITANCE C SHUNTS Rf AND LIMITS MAXIMUM GAIN AND INPUT IMPEDANCE FOR GIVEN FREQUENCY

bottom of this page is required for this level of gain.

ne inverting circuit is usually unsuited for applica-

tions involving high input impedance; a noninverting

configuration is much more appropriate here. By using

low-value resistors in its gain determining network, the

noninverting design circumvents the bandwidth prob-

lem besides achieving a substantially high input im-

pedance.

The inverting circuit holds certain advantages over

the noninverting arrangement, of course. It operates

with one input terminal grounded, and provides a

means for obtaining long-term stability with achopper

amplifier. Also, the inverting configuration obviates any

common-mode errors and operates with inputs of sev-

eral thousands of volts.

Noninverting. In the noninverting amplifier, a very

high input impedance is achieved by opposing the input

signal, V,, with afeedback voltage. Vr,of almost equal magnitude. The amplifier's net differential drive signal, represented as an error voltage, V,, is then equal to the difference between input and feedback voltages, and may be amatter of millivolts or even microvolts in high-gain amplifiers. With only millivolts across the amplifier's differential input resistance, RIN ,the signal current drawn from the source is proportionately low,

V

R R +R

V S

--R4i--1R--2e-) FOR Rf>>R2

Bandwidth limiter. Bandwidth, gain, and input impedance of inverting circuit (top) are limited
by the stray capacitance shunting the feedback resistor. Gain in the closed-loop curve (center) rolls off at 6 db/octave when operating frequency
makes reactance of C smaller than 120.

110

Electronics April 15, 1968

--= INVERTING OUTPUT

R1

R2

V2 NONINVERTING OUTPUT

R2

Vo

(--R-- )

R +R V02 =V2 ( RI- )

NONINVERTING OUTPUT WITH INPUT ATTENUATION

R4

R2+Ri

V03 .( R 3+ R 4 )(V2 )(

R

)

R1

R2

COMBINED NONINVERTING AND INVERTING OUTPUTS
VO4 Vo I+ V0 3

V = 04

+V ( R4

R +R

IRI

2 R3 + R4 I` RI

MAKE R3 =NR 1 AND ReNR 2

NR

R +R

-- VI--ReI +V2(NR I +NR 2 )( IRI

)

R2

R2

VO4 =-- VI--Ri +V2--R1 =iFz (V2 --Vi)

and this gives the effect of an artificially boosted input

impedance. So far as the signal source is concerned,

the amplifier draws an input current of only (V:,- Vf)/

Rix, rather than V R1N, and input resistance is raised

from RIX to approximately ARix X R2/(111 + R2), where A is the open-loop gain. More accurately, input

iwmhpeerdeafnecies

becomes 111N (1+ A/3) in parallel with the feedback fraction R2! (R1 + R) and

Rcin

is the common-mode input resistance, or the resistance

from input terminal to ground.

When atypical operational amplifier with a106 open-

loop gain and a1-megohm input resistance is connected

in anoninverting circuit with aclosed-loop gain, (1//3),

of 50, the bootstrapped input resistance 111is 1megohm

X (1 4- 10"/50) = 20,000 megohms. The artificially

increased input resistance is frequently far higher than

the amplifier's common-mode input resistance, R,.,,,, or

resistance from input to ground.

Consequently, it's the common-mode input resistance

rather than the bootstrapped differential input resistance

that sets the ultimate limit on source-loading effects.

Nevertheless, an operational amplifier with a1-megohm

differential input resistance often has acommon-mode

input resistance of 1,000 megohms, so that this con-

figuration does make a high-input-resistance amplifier.

Internal amplifier bandwidth limitations are much

more likely to set performance levels than external

stray capacitances.

Although the gain-setting resistors, R1 and It., are

shunted by leakage capacitance, the bandwidth lim-

itation for the noninverting circuit isn't as stringent as

the one for the inverting. The noninverting amplifier's

input resistance is independent of feedback resistance

values, but does depend upon their ratio. Actual input

resistance is 111= R1N (1 4- AP) paralleled by the com-

mon-mode input resistance, R Closed-loop gain, 1//3

= (R 1 R2)/R2, can therefore be made arbitrarily high

without designing in high resistance values.

For example, anoninverting amplifier can produce a

closed-loop gain of 1,000 if R1 equals 999 ohms and R2

equals 1ohm. If the amplifier's open-loop gain, A, is

10", input resistance is raised by afactor cf (1 ± 106/

103), or 1,000; the effect of the 1-pf stray capacitance

shunting the 999-ohm R1 is negligible.

In practice, the R1 and R. values are determined by

the amplifier's ability to supply them with sufficient

current without depriving the external circuit of its

load current. A typical amplifier's output rating is -±-10

volts, 5 milliamperes, and if 4 ma is reserved for the

load circuit, the minimum value for (R 1 + R.) is 10

volts/ lma = 10,000 ohms. Therefore, the values of

R1 and 11.. become 9,990 ohms and 10 ohms, respec-

tively. Even so, the 1-pf leakage doesn't begin to roll

off the closed-loop gain much below fo = 1/2 e 104 x

10 -12 = 15 Mhz.

The input voltage capability of the noninverting am-

plifier is certainly no greater, and usually less, than the

voltage of the supply lines. Thus anoninverting ampli-

Merger. One-amplifier differential circuit combines inverting and noninverting operation. Arrangement is economical but tends to exhibit the worst features of the two circuits upon which it is based. Also, it's difficult to vary gain without introducing common-
mode errors.

Electronics April 15. 1968

111

SIGNAL CURRENT, ISig -RIN A RIN '; `f`CM R IN'

INPUT RESISTANCE, Ri, SEEN BY SOURCE= sig
2. Ri=A\ g vo

GAIN

V, vs

-"-·

R2

fl

V

Isig

GAINA

R \

9

COMMON-MODE INPUT RESISTANCE

¡FEEDBACK=V0

R7
Rii-R 2

BOOTSTRAPPING FEEDBACK CAUSES SIGNAL CURRENT TO SEE INPUT RESISTANCE Ri OF APPROXIMATELY

fT*N //
STRAY CAPACITANCE

fier operating from a±15-volt d-c supply is limited to a maximum input voltage of less than ±15 volts--a severe restriction in some applications.
Differential. A combination of noninverting and inverting circuits strikes acompromise between the main features of the two types--but not the best features. The differential amplifier is subject to the disadvantages of both component circuits.
The advantages of the inverting amplifier, as summarized in this article, include immunity from commonmode errors, the ability to operate from high input voltages, and ease of design with chopper-stabilized amplifiers. All of these are sacrificed in the differential arrangement. Similarly, the advantages of the noninverting amplifier--ultrahigh input impedance, alack of bandwidth limitations, and high gain--are also lost in the differential design.
However the single amplifier differential combination does have several advantages. Among these are the ability to measure differential signals with moderate closed-loop gains from 1to several thousands-- a means for improving the CMRR of the basic amplifier by compensation, and lower drift and noise than multiple-amplifier schemes.

--

AR

IN

(RIR+2R

) · 2

ACTUALLY

--

Ria;Rcm IN PARALLEL WITH RiN (I -I-Afl)

STRAY CAPACITANCE C HAS MINIMAL EFFECT ON CIRCUITb INPUT IMPEDANCE, GAIN, OR BANDWIDTH

Feedback helps. Noninverting circuit applies feedback to bootstrap input impedance, and provides high gain without compromising bandwidth. Input voltage range is less than unit's supply voltage, and circuit is
subject to common-mode error.

R2/Ri,to the common-mode gain, Gem = 4 KR./ (R1 + R2). Thus the CMRR for a single-amplifier circuit is (1 Itn/111)/4K. However, the circuit's differential gain, R./RI appears explicitly in this cmroe expression, which may now be rewritten as (1 + G1) /4K. The circuit's cmRn thus improves with closed-loop gain but declines with K, the resistor tolerance error.
For example
With acircuit using 0.1% resistors and operating at a closed-loop gain of 100, the CMRR becomes (1 100)/4 X 0.001, or approximately 25,000:1.
If the same circuit were to measure a100-mv signal superimposed on a10-volt common-mode level, the common-mode error would be 10/25,000/100 mv, or 0.4 mv. The error would thus be 0.4% of the 100-mv signal. But this analysis reflects only the common-mode error stemming from imperfect resistors. The amplifier's internal gain inequality is another source of common-mode error, and it must be considered by the designer.
The amplifier's internal gain, (A2 -- A1), and CMRRA = A/ (A2 -- A1), apply equally to both the amplifier and the differential circuit in which it's connected. Accordingly, if the specification sheet shows the amplifier's CMRR to be 25,000, the additional common-mode error in measuring 100 millivolts superimposed on the 10-volt common-mode level is 10/25,000/100 mv, or another 0.4%.

In the worst case, therefore, where the commonmode errors caused by external resistance deviations and amplifier gain inequalities are present simultaneously, the total error would be 0.8%.
The CMRR resulting from both factors is calculated in the same way as the net resistance of two parallel branches:

total CMRR =

CMRRn X CMRRA CMRRR CMRRA

where cmnnit and CMRRA are the separate values for resistance and gain errors, respectively.

Offsetting gains

A useful design trick here is to trim the external resistors so that the resulting common-mode gain has an opposite polarity to the common-mode gain caused by the amplifier's unequal inverting and noninverting gains. This technique makes, say cmRnR negative and CMRRA positive, eliminating common-mode output and producing an infinite CMRR. The same result can be inferred from the equation for total CNIRR, since the denominator in this expression, cmrmit - ±-CMRRA,would be reduced to zero.
In abipolar-transistor amplifier, as opposed to a FET-input unit, this method can boost the over-all CMRR by afactor ranging from 10 to perhaps 100.
There are hazards, however. If the external resistors drift away from their tweaked-up values, for in-

112

Electronics lApril 15, 1968

» VOcm

R2O+ K)

\hcht

COMMON-MODE GAIN IS

R4 )(RI+R2 )

GCP,Az\ktfeN CM = (RI+2R2 R3+R4

Ri

COMMON -MODE GAIN IS

CMRR

!+R2iR I

4K

4K

Resistance variation. Unequal common-mode voltages,

are applied to inverting and noninverting

terminals when external resistors deviate from assigned values (left). Worst-case common-mode error is

proportional to four times the resistor tolerance fraction K; CMRR improves with closed-loop gain (right).

stance--either through temperature instability or aging--the amplifier's common-mode compensation will also drift. The compensating method depends upon the constancy of the amplifier's internal CMRR, but this parameter varies in response to several factors. For example, curt% decreases in ap-channel FET when the device's applied common-mode voltage increases. It also varies with output loading; the higher the load the lower the gain. Finally, it

recently developed high-performance differentialtransistor amplifiers feature 10° ohms common-mode impedance. Errors due to 1,000-megohm Ren,values shunting 100-kilohm feedback resistances (R2 and R4)amount to only about a0.01% net resistance deviation. Further, because both Ro and R4 are simultaneously shunted by just about equal commonmode values, the net unbalancing effect is unim-
portant.

reflects the long-term aging of internal resistors and Unbalanced source resistance

semiconductors. The designer must therefore familiarize himself
with the amplifier's common-mode characteristics, and should make sure that his external resistors have long-term and temperature-induced drift characteristics appropriate to his accuracy needs.
In practice, it's possible to tweak up adifferential

Besides internal gain inequality, feedback-resistor tolerances, and the shunting effect of the amplifier's common-mode input resistance, unbalanced source resistance in series with the amplifier's input terminals can cause common-mode error in adifferential circuit. For instance, if the signal trans-

amplifier to a near-perfect circuit CMRR level by

making one or another of the resistors slightly variable, or by adding asmall amount of trimming resistance in series or parallel. However, it's extremely

A1+4 2 A= 2

difficult to build avariable-gain differential amplifier capable of ahigh CMRR. It's just about impossible to replace R2 and R4 with a ganged pair of variable resistors and secure the same cmmi because of the difficulty of maintaining good tracking be-

\be

COMMON-MODE OUTPUT, Vccm
DUE TO UNEQUAL GAINS:

tween these feedback resistors. Careful common-

I

A

A

mode trimming would come untweaked. Another source of common-mode error is the un-
balancing effect of the amplifier's own commonmode input resistance, Rem ,the resistance seen between input terminal and ground. Because the com-
mon-mode resistances between ground and the inverting and noninverting terminals are, in effect, placed in parallel with feedback resistors R2 and R4, they modify the common-mode voltage applied to the two input terminals. These resistances are the-

NR 2

VOcre =\fieR2+Ri

EQUIVALENT COMMONMODE ERROR, ecm,

THAT WOULD CREATE SAME C-M OUTPUT IS:

Vo

R-&-- A -AI

ecm =-7tre =Vcm (R--et.

CMRR

-CCOOMMMMOONN

MODE MODE

VOLTAGE INPUT (\lad ) INPUT ERROR (em)

oretically equal, but in practice are never identical. Errors due to common-mode resistance are mini-

CMRR Vol ÷Vav

et»)

A2A-A,

mized by selecting small values for Ro and R4 compared with the nominal Rem level, or by using an amplifier with very high common-mode input resistance, such as the FET or varactor bridge. Even

Matching errors. Amplifier's internal common-mode error due to gain inequality reflects aCMRR to the circuit's input that is equal to that amplifier's own CMRR: A/(A2-Ax).

Electronics lApril 15, 1968

113

R1
2

R2
W/
Vo
KVo--e
V0 .VS(R-5-1 )( 2K--)

ducer is operated with one of its output terminals grounded, point A in the diagram on page 115, its internal resistance or impedance is placed in series with the amplifier's inverting terminal. The two signal lines introduce further series resistance, but imbalance remains if the source resistance is appreciably higher than the signal-line resistances. The net imbalance is represented as R,, in the schematic.
It's theoretically possible to introduce acompensating resistance into the noninverting line to cancel the effect of R,,, but this can be a difficult job in practice. What happens when the amplifier is switched sequentially to read the output from an array of different transducers, each with different amounts of imbalance? Or what happens when signals are developed by an inductive-type transducer, such as a tape-recorder head, whose internal impedance varies with ground-loop and common-mode frequency? In both these instances, and in many others, common-mode errors cannot be completely compensated.
Actually, the degree of common-mode error doesn't depend upon the absolute value of resistance imbalance, but is proportional to the ratio of source resistance imbalance 11,, to amplifier input resistance Re,,,, Ru/Rem. The higher the amplifier's common-mode input resistance, Re., the smaller the common-mode error. The best tack to take, therefore, in the absence of external common-mode compensation techniques, is to make the amplifier's common-mode input resistance as high as possible.
Amplifiers are typically rated--regarding common-mode characteristics--on the basis of their source resistance imbalance; this R,, value is often 1,000 ohms. To provide 10° CMRR with such avalue requires aminimum common-mode input resistance of Rem := CM» X R,, «-= 10° ohms. If the amplifier is to be used to measure 10-mv signals against a 5-volt common-mode background, the equivalent common-mode input error, e,,,,, becomes 5/10°, or 51.w. The percentage error, 100% X eciu /V., works out to avalue of 100% x 5X 10-6/10-2 := 0.05%.
Attenuating effect
The amplifier's finite differential input resistance is usually smaller than its common-mode input resistance, and this creates an attenuating effect when the device is used to measure signals from sources with appreciable internal resistances or impedances. This attenuating effect, in turn, causes ameasuring

Adjusting gain. Although asingle resistor is all that's
needed to adjust gain of circuit at top without altering common-mode balance, six high-stability resistors are needed in the feedback circuit. Gain varies nonlinearly with K. Center circuit uses only four feedback resistors, but requires an auxiliary amplifier for unloading resistor K. Gain here also varies nonlinearly with K. Circuit at bottom provides
linear gain variation with aid of auxiliary amplifier, and uses five feedback resistors.

114

Electronics iApril 15, 1968

Ru REPRESENTS NET RESISTANCE UNBALANCE IN SERIES WITH INPUT SIGNAL (R,<< Rcr,A)
(

AMPLIFIER HAS CLOSED LOOP
Vo /GAIN, GcL. vi -v2

-- GROUND

IMPEDANCE

R Zg < <

CN/

V1 =VA AND =VA(R-u5-·-faie-cr)4
(Rcm » Ru )

serious loading errors, and, if single-ended, substan-
tial common-mode errors, too. Differential configurations with two separate op
amps can generally handle the problem of commonmode error better than any single-amplifier circuits. A differential design based on two noninverting amplifiers benefits from this type of circuit's high input impedance and relative immunity to capacitance strays. Likewise, adifferential circuit based on two inverting amplifiers can remain immune to internal
common-mode error with high input voltages. Common-mode error due to external resistance
deviations recreases in the noninverting circuit with closed-loop gain; in the inverting configuration, CMIIR is constant. But gain equalities within the two amplifiers in the noninverting design cause error. In the design based on two noninverting amplifiers, closed-loop gain can be varied in proportion to the output amplifier's feedback resistor.

-GROUND

Key spec

VOLTAGE

The specification that really inhibits the use of

conventional op amps in differential data-measuring

circuits is common-mode rejection. Unfortunately,

CMRR - DIFF GAIN 'NJ

GCL

CM GAIN

(GcL XVRekt)

there are few useful operational amplifiers with a CMRR beyond 500,000:1; those op amps emphasizing

Single-end source. Differential method can reject common-mode errors when working with single-ended sources, although resistance imbalance impairs the
rejection process. Over-all CMRR is boosted by selecting avery high common-mode input resistance

CMRR tend to suffer from high cost or some other parameter deficiencies.
However, for more practical applications where the signal source is alow-impedance thermocouple or strain-gage bridge, no currently available opera-

compared with the resistance imbalance.

tional-amplifier model fits the cmiut requirements

set forth and at the same time features high stability,

discrepancy called source-loading error, an error open-loop gain, input impedance, and fast response

equal to RS/RIN where these symbols represent at moderate cost.

source resistance and the differential input resist-

There's therefore aneed for adata amplifier de-

ance of the amplifier. With a 1,000-ohm total source resistance and a
typical amplifier, the differential input resistance RIN must be higher than 106 ohms if the loading error is to be held below 0.1%. Percentage loading error equals 100% X R./RIN.
Not only then must the amplifier's common-mode

signed from the ground up. This device would achieve adequate performance at reasonable cost and the op amps used as building blocks cannot meet cost and performance specs if such features are required as 106 CMIIR, 2,000 maximum gain, 109 and 107 common-mode and differential-input
impedance, and 2p.v/°C drift.

input resistance be very high to reduce commonmode errors caused by source imbalance but the differential input resistance must be very high to hold down source-loading errors.

A differential amplifier that's immune to commonmode errors caused by resistance deviations appears at the bottom of page 116. However this design is still subject to gain inequality between the

Other error sources

two amplifiers. The error analysis reveals that the circuit has

Drift is amajor factor in measurement accuracy. unity common-mode gain when the two amplifiers

If an amplifier with a2 v/°C maximum drift oper- are considered separately. And because both ampliates over the temperature range of 25°C to 35°C, fiers have this same unity common-mode gain, the

the equivalent input error is 10 X 2= 20 kw, which creates--for 10-mv signals--a further 100% X 20 X 10 -6/10 -2 = 0.2% measuring error.
Current drift, or pump-out current, must also be

common-mode output measured between the output terminals is theoretically zero. This means that the common-mode differential gain is also zero, and the circuit's common-mode rejection ratio is theoreti-

considered when the source impedance is apprecia- cally infinite.

ble. If the total source impedance is 10,000 ohms,

Galvanometers, relays, coils, and other isolated

for instance, the input error caused by a300 pico- loads can he driven directly from the push-pull out-

amperes/ °C current drift for a -±-10°C range is put with near-perfect immunity to resistor-induced

10,000 X 300 X 10 - 12 X 10 = 30 ¡iv, or a100% X 30 X 10 -6/10 -2 0.3% measuring error.
A source impedance of 104 ohms could create

common-mode errors. But an added stage of differential amplification is needed for single-ended loads.
For an error-cancelling circuit followed by a

Electronics April 15, 1968

115

R 0-K) v(I+K)

R(I-K)

/VARIABLE NR O+ K)

1( I-K) R1(l+ K)

VARIABLE R2(I-K) i030+ K)

COMMON -MODE GAIN =4K DIFF GAIN 1+N GcL
CMRR - C-M GAIN = ·4K 4K

R2(I+K) COMMON -MODE GAIN =4KGGL CMRR =DCI-FmF GGAAIINN _4KRR33//RR22 4K

Pairing amplifiers. Coupling two noninverting amplifiers gives differential circuit high input impedance
and a CMRR that improves with closed-loop gain. However, the circuit is susceptible to amplifier's internal common-mode errors, has limited input voltage range, and requires isolated power supplies when based on chopper-stabilized amplifiers (left). Alternative circuit (right) uses two inverting amplifiers, has constant CMRR for external resistance deviations, handles high input voltages, is immune to common-mode error
of individual amplifiers, and can be based on chopper-stabilized amplifiers without needing special power supplies. However, input resistance is limited to the value used for R.

differential-to-single-ended-interface amplifier the over-all gain of the two cascaded stages is given by
Gain (A) X Gain (B)
and the total cmnit is Gain (A) 1+ Gain (B )/4K. The circuit's common-mode performance can be
maximized by assigning most of the gain to the first stage; in fact, fractional gain for the second stage appears to improve CMRR considerably.
This advantage can't be pushed too far without running into another source of difficulty. Designing the first stage for high gain will either restrict the level of common-mode voltage or cramp the circuit's dynamic signal swing.
Because the individual amplifiers used in the first

stage operate with unity common-mode gain, their
Output signals Van' around the common-mode level,
Vern ,of the input. If, for example, Vein is 9.5 volts, and the amplifiers are built for a -±10-volt output rating, the maximum output signal swing can't be greater than 10 -- 9.5 or 0.5 volts.
A circuit with 100:1 first-stage gain couldn't handle input signals larger than 0.5/100, or 5mv, without driving the output into the stops. Large input
signals could only be handled either by using lower values of first-stage gain or by reducing the common-mode level upon which these signals are superimposed.
The future trend for improved GMER in amplifier circuits will come from improved technology in

CONNECT INPUT TERMINALS TO COMMON-MODE SOURCE, Vcm
(A)

VoA = -1- F..,1(12+-K)- (Vi--V2) BUT VI=V2=Vcm SO VoA =Vom

VOB =V2+R3(RI2-K) (V2 VI) BUT V2=VI=Vc m SO VoB=Vcm
Differential immunity. Differential circuit is immune to common-mode errors caused by resistance deviations, but remains susceptible to the amplifier's internal common-mode errors. It can drive galvanometers, relays, magnetic coils, and other isolated loads without requiring conversion to single-ended output.

116

Electronics IApril 15, 1968

resistor and transistor manufacture, and innovation in circuit design.
In the area of thin- and thick-film resistors long-term stabilities of better than 5ppm per year and very close ratio temperature tracking, less than 1ppm/°C, will improve circuit mural.
Monolithic manufacturing techniques with both bipolar and field effect pairs should improve the voltage feedback ratio balance on bipolar transistors and result in both higher ratios of small forward transconductance to output conductance of an FET and closer matching with aresultant higher CNTRII capability for the amplifier.
Another article in a subsequent issue will describe the problems of ground loops, and the use of operational amplifiers to solve them.
Bibliography
D.B. Schneider, "Designing for Low Level Inputs," Neff Instrument Corp., Electronic Industries, January 1961.
L.V. Mayhead, "The Measurement of Small Signals in the Presence of Common Mode Interference." Digital Measurements Ltd., Electronic Engineering, July 1962.
A.S. Buchman, "Noise Control in pow Level Data Systems," Electromechanical Design, September 1962.
E.L. Stewart, "Ground Loops (Electrical): The General Case and an Example," Analog Report No. 15, July 1963.
R.B. Fradella, "Isolating the Causes of Common-Mode Noise," Electronic Design, August 1963.
Peter Pohl, "Common-Mode Rejection," Dynamic Instrumentation, 1963.
D.H. Sheingold, "Grounding Low-Level Instrumentation Systems--A Coherent Philosophy," Electronic Instrument Digest, January-February 1966.
Ronald R. Jennings, "Source and Load Impedance: Effects on Closed-Loop Characteristics," U.S. Naval Avionics Facility, Electro. Technology, September 1966.
Jim Rose. "Straight Talk About Data Amplifiers," EDN Magazine, Nov. 23, 1966.
Ralph Morrison, "EID Surveys the Scope of Instrumentation Amplifiers," Dynamics Instrumentation Company, Electronic Instrument Digest, March 1967.
"Instrumentation Amplifiers: A Survey," Electromechanical Design, March 1967.
Morton H. Levin, "Advantages of DirectCoupled Differential Data Amplifiers," Hewlett-Packard Journal, July 1967.
Richard Y. Moss II, "Errors in Data Amplifier Systems, Hewlett-Packard Journal, July 1967.
"Minimizing Common-Mode Noise," Control Engineering Data File 117, July 1967.
"Application Notes for Differential DC Amplifiers," Dynamics Instrumentation Company.
"Differential Amplification," Applications ZA102, Zeltex, Inc.
"Floating Power Supplies," Applications ZA103, Zeltex, Inc.
Ralph Morrison, "Selecting a Differential Amplifier," Dynamics Instrumentation Company.
Ralph Morrison, "Shielding and Grounding for Instrumentation Systems, Dynamics Instrumentation Co.

GAIN A

R4(I - K)

GAIN B R5(I+K)

V0 =1R141 0+ RiR+R23 )(VS)

Vpo =Vs(GA1N A)

R5(1-K)

V =V

4KR5

Ocm CM R4 +R5

Vo =Vpo (GAIN E)

VP0 ^-· VS(I+ R2)

0"s"' PQ R4

SECOND STAGE CONVERTS Vcm AT P AND Q INTO COMMON-MODE OUTPUT V .v _4tn_)
00 .1 CM` R4i-R5
DIFFERENTIAL COMPONENT OF Vcm AT INPUT, ecm ,IS C-M OUTPUT DIVIDED BY OVER-ALL DIFFERENTIAL GAIN; tacm =Vocre4GAIN AXGAIN Bj

Rpr, x-F,-)( KR5 /

_

4K RR R4

e eCM -VCM (474711-5-)/(1+-117--)(e VCM

GAIN A)

GAIt' A vcm
OVER-ALL CMRR =--ecni
\lee( 4 K R4 )

CMRR =Vcm :( GAIN A5 )

CMRR: GAIN

_F!" R4 )

CMRR =GA4IKN A (1+GAIN B)

G+AIN B

(GAIN AXGAIN B)=100

CMRF.

GAIN A
0.1
I.0 10.0 100.0 1000,0

GAIN B
1000.0 100.0 10.0 I.0 0.1

GAINA (Ii-GAIN B) 4K
100.I/4K 101/4K 110/4K 200/4K I100/4K

Converting an output. Right-hand differential stage develops single-ended output from push-pull input. Arrangement provides high input impedance and permits the use of low-value, high-tolerance resistors for wide bandwidth
and maximum CMRR. Chart lists advantages of having first stage contribute most of the gain. But the superimposition of output signals at Pand Q onto the common-mode voltage, Ve.,,, cramps dynamic range or signal gain or both. If the common-mode voltage approaches maximum amplifier output voltage, the circuit develops only small signal excursions at Pand Q;
large excursions would drive the first-stage amplifiers into saturation.

The author

Robert I. Demrow, astaff engineer at Analog Devices, has the job
of finding new applications for operational amplifiers, evaluating the devices' performance, and checking out problems. He received his MSEE from Northeastern University in 1958, and has worked for GE, the Foxboro Co., and Honeywell.

Electronics IApril 15, 1968

117

Be alighting bug collector...

Surprise your friends... Impress your boss.
More important, have all the engineering scoop on miniature lamps available when you need it.
That's what our lighting bug program is all about. Getting technical data on Chicago Miniature lamps where it can assist you the most. In your files, ready to be applied on any application that comes up. We have all the species.

Miniatures, sub-miniatures, hardware lighted devices and specially engineered varieties. Aerospace, aircraft, appliance, communication, computer and business machine, control panel and
switch, instrumentation, optical, marine, medical, radio, TV, telephone, transportation ... name your application and chances are, we've got aminiature or subminiature lamp that will do the job better.

Get your personal lighting bug collection. Send for it, today.
Even if you don't have any friends.
For application assistance, contact your Chicago Miniature Sales Representative. For off-the-shelf delivery, contact your local Authorized Chicago Miniature Electronic Distributor.

Chicago Miniature Lamp Works

4433 N. Ravenswood Ave., Chicago, Illinois 60640, (312) 784-1020

118

Circle 118 on reader service card

Electronics April 15, 1968

Industrial electronics
Saving money on data transmission as signals take turns on party line

Proposed system L.i,es a single two-wire ca ble to connect all stations of acontrol or monitoring installation, and gives each transmitter and receiver its own listed number in binary code

By James W. Cofer Jr.
Georgia Institute of Technology, Atlanta

Even before the copper strike, when wire cost less, the long runs of data-transmission cabling in a
control system made up abig part of the system's cost. To make matters worse, installation costs far more than the cable itself. For example, the
over-all cost ranges from 50 cents to $1.50 arunning foot for three-conductor, 14-gauge, armored cable--depending on terrain and other conditions-- even though the cable itself costs only about 5cents
afoot. Thus, amajor goal in digital monitoring and control systems has been a simple data-transmis-
sion method that's stingy with wire.
This goal seems feasible with a new system that can be made from readily available, low-cost, digital components such as flip-flops and logic gates. The method, which looks especially good for smaller installations, does away with the need
for individual lines to each station. Only one two-
wire cable--one wire for data bits and the other
for timing pulses--is necessary. Called a circulating pair, the two wires (three
if an earth ground isn't satisfactory) are run close to each transmitter and receiver. Short runs of other
wire pairs connect these stations to the circulating
pair.

The author

James W. Cofer Jr. received abachelor's degree in electrical
engineering from the Georgia Institute of Technology in 1967. He is an assistant research engineer in the electronics division of Tech's experiment station and continues his studies part-time.

Any transmitter and any receiver can be hooked to the line anywhere along its length, giving extreme flexibility for system installation. Alternatively, all transmitters may be relatively close at one end of the circulating pair and all receivers clustered at the other, or transmitters may be connected along the line and the receivers grouped at one end. Or receivers may be divided into groups, each group installed on a console for surveillance by plant operators. Each station has its own binary address and handles only those messages intended for it, no matter where it is.
Call information
The system can be used for both analog and digital transmission, but only an arrangement with
all-digital inputs will be described. A key part of any configuration is the scanner that generates address codes to connect transmitters and re-
ceivers. The address scanner clears previously sent codes
from the system, addresses corresponding pairs of transmitters and receivers in sequence, then idles long enough for the messages to be sent and received. The scanner does this until all pairs have communicated, then repeats the cycle.
To clear the data line, the scanner sends aseries of binary ones-1111. The address code, though, is a series of binary l's and O's, each series corresponding to an address built into the transmitterreceiver pairs. For a system with 15 such pairs and one clear word, the 16 code combinations can be obtained with four binary bits. That is, 24 = 16. In the message itself, every fourth bit must be a 0to prevent the appearance of the all-l's sequence that would clear the system.

Electronics IApril 15, 1968

119

The scanner produces a string of binary pulses whose length is the sum of the clear, address, and message words. The system in this example, with 15 pairs, one clear word, and a six-bit message, requires a 16-pulse sequence as represented by
1111 AAAA XXXO XXXO where the l's are the clear word, the A's the address word, which can assume all binary combinations (0000 to 1110) except 1111, and the X's the message, which can assume all binary values, with, as noted, O's always in every fourth position.
Ringing up
The pulses come from a ring counter driven by a fixed-frequency digital clock, as shown in the schematic for the address scanner [see p. 121]. The ring counter is an eight-stage shift register whose outputs are fed back into the opposite inputs. Each stage of the shift register is astandard J-K flip-flop with capacitively coupled inputs for set and reset.
Each time a pulse from the digital clock enters the ring counter, one of the eight flip-flops changes to its other state, emitting a pulse and thereby advancing the ring counter. Thus, the ring counter has 16 states, and for every pulse from the digital clock, a different one of the ring counter's 16 outputs will emit a pulse in the time sequence 1,2,3,4 ...15,16,1,2. ...These pulses drive not only the next ring-counter stage but also other electronics in the system.
Pulse-positions 1through 8place the clear word and the address code--that is, 1111AAAA--on the data line. A single flip-flop clear-word generator, connected through an on gate to the data line, is cut on by pulse 1from the ring counter and shut off by pulse 5. It allows four l's to be produced in all transmitters and receivers to clear out previous address codes.
The address generator--a four-bit counter--advances one bit every time it receives an input pulse from one output of the ring counter. (The selection of output 3to do this is arbitrary.) With this input

the address generator develops a unique code combination for each successive group of 16 pulses from the digital clock. Thus, in sequence, it develops 15 unique codes-0000 to 1110. The 1111 combination--clear-word code--is kept from developing by a d-c signal that resets the counter to 0000. 'When the four l's are present they instantly operate through the AND gate to provide the reset signal.
Ring-counter output 5, the one that has shut off the clear-word generator, causes the code stored in the address generator to be read out in parallel into the shift register. Pulse 5 also moves one of the bits just entered in the shift register onto the data line, and pulses 6, 7, and 8--via athree-input monostable multivibrator--send the other three address code bits onto the line in sequence. Finally, pulse 9removes any binary-1 voltage placed on the data line by the scanner. Having addressed a transmitter-receiver pair, the scanner now remains off the line for the next eight pulses, which are the message.
Getting ready
The transmitter for handling a six-bit message word is also made of flip-flops, capacitively coupled inputs for set and reset, and logic gates [see p. 122]. The address detector--four flip-flops --on the transmitter senses the clear word and then the address code.
The address for the transmitter is coded by the way the four dashed-line inputs of the lower AND gate are connected to the four flip-flops. For example, to build in an address of 1100, the two inputs of the AND gate are connected to the true (binary 1) outputs of the first two flip-flops, and the other two inputs of the gate are wired to the complementary (binary 0) outputs of the third and fourth flip-flops. This code is built in when the transmitter is wired, and can be changed only by rearranging the connections.
The transmitter must first clear its address detector of previous codes so it can receive its own

Tk

R k

Circulating pair. Two wires connect all transmitters and receivers but only one transmitter and receiver talk at atime.

120

Electronics rApril 15, 1968

RING COUNTER

ADDRESS GENERATOR

13

V D

CLEAR -WORD GENERATOR

6 7

PULSE GENERATOR

8 O.

5

º SHIFT REGISTER

o
ID TO DATA LINE

Address scanner. The scanner generates a clear-word code, then an address code to connect corresponding pairs of transmitters and receivers.

code. This is done by the address detector and the upper AND gate to the left of the detector. This AND gate is permanently connected to the four true outputs of the flip-flops. When the first bit of the clear word arrives at the address detector, it sets the flip-flop on the far right to 1. This 1 shifts left and sets the adjacent flip-flop to 1when the next 1 in the clear word arrives at the right
flip-flop. The sequence continues until all four flip-flops contain a 1. That is, the address register has now sensed the arrival of the clear word. The AND gate then emits ad-c signal to reset the address detector.

respondingly addressed receiver. The last 0 is transmitted to ensure that the shift register flipflops respond properly.
To prevent the transmitter's address detector from answering abinary sequence in the message word that could be the same as the address code, the detector must be shut off after it receives its four-bit address. This is done by a "4" counter,

Moving the bits

The detector is now ready for its second job-- responding to its address. If the code sent down
the data line is 1100, then, in this example, the lower AND gate produces apulse that loads eight bits--the six of the message and the two extra O's-- into the lower shift register.
The next eight clock pulses move these eight bits onto the data line to be detected by the cor-

Electronics lApril 15, 1968

121

Talking in turn
D-C RESET

T

T

AE S DETECTOR

--1.--

"4" COUNTER

· TO RED AND Ge

X4
L,

_

CLOCK LINE

DATA LINE

SHIFT REGISTER

Digital transmitter. Turned on when it senses its unique address code, the transmitter then puts the binary message on the data line.

ADDRESS DETECTOR

"4" COUNTER

D-C RESET

·

·

TO RED AND GATE

,

SHIFT REGISTER

"8" COUNTER
CLOCK LINE DATA LINE

I

I

I

X6

X5

X4

X3

X2

Digital receiver. Storing the message serially, the receiver's shift register reads out in parallel when it senses the last pulse.

122

Electronics lApril 15, 1968

the three-flip-flop counter at the upper right. When the "4" counter contains the code 100, the binary equivalent of 4, it places a0on one input of the lower AND gate and cuts off the address detector. Simultaneously, this 0is fed back to the AND gates associated with each stage of the "4" counter. The counter then shuts off, and can be restored to 000 only by the same d-c reset signal that detects the presence of the 1111 sequence, or clear word.
Sensing the message
The receiver, opposite page, is similar to the transmitter. In fact, the two circuits' clear-word and address detectors and three-bit "4" counters are identical.
The receiver senses and stores the messageword pulses from the data line. The eight-bit message sequence is detected serially by the sevenstage shift register, the first pulse coming in at the left and shifting to the right with each succeeding pulse. Only seven of the eight transmitted bits have to be stored in the receiver because, as noted, the last 0in the sequence isn't part of the message.
After the seven-bit message has been sensed by the register, the "8" counter, at the lower left, emits apulse that causes all stored bits to be read out in parallel. The "8" counter operates like the "4" counter, except that it has four flip-flops so it can produce the output pulse when the counter contains 1000, the binary equivalent of eight. All bits on the line pass through the receiver register, but parallel readout takes place only when the proper address is present.
Finding sequence length
The number of pulse positions, p, required for one sequence can be found from the formula
p = 2n ± nn--m 1)
where n--the length of the clear or address codes-- is the number of binary bits needed to distinguish the number of circuits, k, as determined from 2° = k 1, and m is the message word length before the extra O's are inserted to prevent the appearance of the clear-word code. The factor (n -- 1) tells how many bits in in can be used in sequence before a0is inserted.
If the parenthetical expression in the .formula doesn't result in an integer, then m is extended with enough O's to make the term equal the next highest integer divisible by n. The number of flipflops in the ring counter is half the number of pulse positions in the total sequence.
For the arrangement described previously, the number of pulse positions is
2 X 4 -I- (4X 6) _ 8 + ( 24 ) _ 8+ 8= 16

and the ring counter thus has eight flip-flops. For asystem that also has 15 circuits (n = 4),
but uses amessage length, m, of eight bits, then

nm ) n-- 1

4X 8 = 1-2- = 10 --2

3

3

3

This won't work. The next highest integer divisible by 4, of course, is 12. Thus the sequence requires 8 ± 12 = 20 pulse positions and looks like
1111AAAA,00C0,00C0XX00
The next-to-last 0 has been added to fill out the message word. For this system, the ring counter needs 20/2 := 10 flip-flops.
To complete acycle of sending amessage to all stations requires pk pulses, where p is determined as above and k is the number of transmitterreceiver pairs. For the arrangement in the main example, pk = 15 >< 16 = 240 pulses. The value pk helps establish the pulse frequency of the digital clock. If, for example, the installation requires that any change in any input appear at its corresponding receiver within five seconds, then the clock rate is
CR = pk/T = 240/5 = 48 pulses per second.
For such a system, a 60 pps clock rate would probably be used because it is easily synchronized with power-line frequency.
A choice idea
This idea for multiplexing data from many input stations over asingle two-wire line (and aground) can be used in many ways. The binary message word needn't be for a numerical value; it could represent the states (on-off) of agroup of switches that indicates the operational status of apiece of equipment. The station pairs, instead of being interrogated continuously, could get aburst of pulses only once every few minutes.
Used with alarger digital data acquisition system or with a computer control installation, the data link's receiver-readout register could be part of the computer or connected to it. These receivers would store inputs at their own rate, and the computer could interrogate them at a different rate, depending on its own needs and priorities. For example, the computer wouldn't have to wait while pulses are accumulated from aturbine flow meter.
However, the system won't be feasible for encoded digital transmission from the measurement site of such analog-process variables as temperature, pressure, and level until someone develops an analog-to-digital converter and storage register small and cheap enough to be installed at each transmitter. Several makers of controls are investigating this area, and are looking to large-scale integrated circuits as an answer. How soon these devices appear on the market depends on the economics of Ls' on the one hand and user demand for digital sensors on the other.

Electronics April 15, 1968

123

Computers
FFT shortcut to Fourier analysis

Mathematics, not electronics, enables engineers to develop faster ways of extracting information from complex waveforms

By Richard Klahn and Richard R. Shively
Dell Telephone Laboratories, Whippany, N.J.

Major advances made by engineers in producing faster data-processing systems usually stem from the development of electronic devices. But this is not the case with signal- and data-analysis applications involving Fourier transformation techniques. Here, the advances have been triggered not by electronics, but by mathematics.
Fourier transformation is auseful tool in extracting the information contained in many kinds of waveforms--such as seismic waves, electro-encephalograms, and data signals telemetered from deep space. Many approaches have been taken to find the energy content of these frequencies. One familiar and inexpensive method calls for abank of filters. But this is an analog approach, which is inherently limited in resolution and flexibility. Although digital techniques are better, they are difficult to apply. The straightforward digital form of the Fourier transform, for example, has proved costly in computer time. However, this has changed.
Cooley, Tukey and the FFT
About three years ago, the International Business Machines Corp.'s James W. Cooley and Bell Telephone Laboratories' John W. Tukey developed a technique for rapidly computing the spectral components of a waveform containing many frequencies. Their mathematical innovation, which has come to be known as the fast Fourier transform (Err) reduced the computational effort required to obtain discrete Fourier transform coefficients of digital data, and made practical the use of digitalcomputing systems in anumber of design problems, data analysis applications, and signal processing functions. To the engineer concerned with the filtering of data, or determining the spectral distribution of power in an electrical signal, the CooleyTukey technique is as important as any piece of hardware.

This led to the development of FFT programs for general-purpose computer systems as more and more engineers wanted to use the Fourier transforms. But even with FFT, general-purpose computers are impractical for some applications that involve large amounts of data and require results in a reasonable amount time. For example, realtime signal processing of information demands a very fast execution rate. And this holds true for simulation studies involving random data and requiring thousands of transformations. For such applications, special-purpose processors organized to execute the algorithm would be far better than general-purpose computers running FFT programs.
From a computer designer's standpoint, FFT permits some interesting specialized designs in processors that, as a result, have much shorter execution times than are obtainable on generalpurpose computers built with the same kind of components. For example, because the computation involves an arithmetic sequence that is always the same, an arithmetic section's speed can be closely matched to that of amemory, allowing an overlap of arithmetic operations and memory transfers. Moreover, both units could handle the real and imaginary portions of complex values in parallel, thereby saving processing and transfer time.
Factor of hundreds
Without the FFT algorithm, the number of arithmetic operations required to compute the discrete Fourier transform from N samples is proportional to N2.With the FFT algorithm, however, the number of operations becomes proportional to N log.N. Therefore the factor of improvement is
N2/(N log2N) = N/log2N,
which is approximately 100 for N = 1,024 and more than 600 for N = 8,192--the capacity of the processor's memory.
The algorithm attains its speed because it shares

124

Electronics IApril 15, 1968

èree1111 , ·111.·

intermediate results to the greatest possible extent. Without the FFT, each Fourier coefficient is computed itself, using all the input samples.
The Fourier series can be expressed in both continuous and discrete form. In continuous form, the Fourier series can be written as an infinite series of either real or complex terms. The sum of the infinite series is exactly equal to the original function; a finite sum is an approximation. In real form, the Fourier series is expressed as a summation of an infinite series from zero to plus infinity. A periodic waveform is described in terms of a fundamental frequency and various harmonics, or multiples of the fundamental, and can include ad-c term. Phase differences between the harmonics are accounted for by the presence of both sine and cosine terms in the series. The period of the fundamental equals the period of the waveform.
A complex form is obtained from the real form by expressing the sine and cosine terms as the sum and difference of complex exponentials:

sin kx

=

1 2j

[exp

(jkx)

-- exp

(--jkx)]

ms kx = 21-[exp (jkx)

exp (-- jkx)]

After substituting the exponentials, algebraic manipulations result in a doubly infinite summation-- from minus infinity to plus infinity. Each term in

the summation is the product of two numbers--an amplitude derived from the coefficients, and an exponential that expresses the phase.

Sampled signal
The digital or discrete form of the Fourier series is analogous to the complex continuous form, except that it deals with uniformly spaced samples extending over aspecified interval of the waveform. The closer together the samples are taken, the more accurately the resulting series represents the original waveform. Because the method is digital, it cannot operate directly on the continuous waveform. Moreover, practical equipment precludes the extension of this method to positive or negative infinity. The sum of the finite series, considered as coefficients of successive harmonic frequencies, is an approximation to the original waveform:

f(t)

EA(n) exp (jcunt)

The nth Fourier coefficient, D(n), with aset of N samples taken at uniform intervals throughout asegment of awaveform, is obtained by multiplying each sample by anumber exp( --j2irns )¡N, adding the products, and dividing the sum by N. The number sis the index of aparticular sample during the computation of one summation for aparticular co-

SAMPLES OF FUNCTION

X(0)

X!I)

X(2)

X(3)

X(4)

X(5)
._ML, L, r
in ,I.',.-- w ,N 8 -_ N
'-A '

X(6)
,2_, 4c
'CPA 1.0- W bi

, _o K(7)
`1r·C-M, --We

2- POINT TRANSFORM

A (0)

A1 (1)

A 1(2)

A11 (3)

o FCATF0-- W 8

r gC-1M-rro,--

o
W _8

.._ t

A1 (4) 41-- _

trm.--A,1-..11.m

A1 (5)

A1( ,61

A1(7,)

rmbrC---M-rJ"r'1-4- w8

r--tr

1-

i CMJ.0-- W 8

s.

- - - mr-N",m

..-- t

;··-A-tt·

4-POINT TRANSFORM

A2(0)

8-POINT TRANSFORM

A3 (0)

A (1) --iti

A2 1(2)

A2 1(3) L

·I I-· --.-_:>"--_-_

----

r7,'-r U-.'r ..'s

I fl-

?a·--A---1J1m

+

'ii'

A3 (1)

A3 (2)

A3 (3)

A2(4) 2
A3 (4)

A2 (5) r-L1·1
8 CM 1.0-- W

A2(6) 1

A2 (7)

r- L-1

3

i 1 CM
ir

8.11-- W I

A--

$

A3 (5)

A3 (6)

A3 (7)

REORDERED COEFFICIENTS

c(o)

c(t1)

Ct(2 )

C(3)

C(4)

C(5)

+
C(6)

IIIII 'COMPLEX MULTIPLIER IIM 'COMPLEX ADDER 111111 'COMPLEX SIGN CHANGE

C(7)

Transform procedure. The fast Fourier transform first combines pairs of samples into two-point transforms, then turns these into four-point transforms, and so on, until asingle transform is obtained based on all the original samples.

Electronics April 15, 1968

125

Digging out buried signals

A small, two-year-old company in Palo Alto, Calif. --Time/Data Corp.--was the first to market a spe-
cial-purpose computer designed specifically for Fourier analyses. Just a few short months ago, Time/Data delivered its first three machines to the Environmental Sciences Service Administration, the
Air Force, and the University of California's Brain Research Institute.
Called the Time/Data 100, the computer's job is to find biochemical, radar, sonar, seismic, or other signals that are buried in noise--and to find them in real time. The computer does this by calculating the Fourier coefficients of the complex waveform in which the signals are buried. Other jobs the machine can perform are auto- and cross-correlation, auto- and cross-spectrum analysis convolution, and averaging functions.
Lost and found. In 1942, mathematicians G.C. Danielson and Cornelius Lanczos published an algorithm--a method of calculation--for arapid Fourier transform. But for some unknown reason the process was somehow "lost." Only when Cooley and Tukey revealed their own fast Fourier transform in 1965 was the older algorithm rediscovered.
The Cooley-Tukey algorithm set off a flurry of renewed interest in computer-assisted Fourier analysis. The Bell Telephone Laboratories' signal processor, designed by authors Klahn and Shively, also incorporates the algorithm [Electronics, Sept. 4,

1967, p. 40], and is being used for research. Bell Labs doesn't intend to market the machine.
Sylvania Electric Products Inc., developed asimilar machine for digitizing speech signals, and the International Business Machines Corp. is also working on one [Electronics, Oct. 30, 1967, p. 26].
Ten-year project. Time/Data's machine is the brainchild of mathematician Edwin Sloane, who got the idea while working on the distant-early-warning-
line (Dewline) project at the Massachusetts Institute of Technology's Lincoln Laboratory. Sloane spent 10 years developing the algorithm, which he calls the rapid Fourier transform--so-called to distinguish it from Cooley's and Tukey's fast Fourier transform. Sloane's algorithm is based on the Danielson-Lanc-
zos method. The rapid Fourier transform compares the input waveform with a series of sinusoidal "templates" of various frequencies previously wired into the machine.
Says Sloane: "The integral of the product of two sine waves in phase is larger than any other integral involving sine waves out of phase or of different frequencies."
The transform takes advantage of redundancies in the sine and cosine functions. Sloane and Martin Fletcher, Time/Data's vice president in charge of engineering, chose to take advantage of these redundancies to gain speed, by "pipeline" processing. This arithmetic technique uses several small fast

Excavator. Time/Data Corp.'s special-purpose Fourier analyzer extracts signals buried in noise. 126

Electronics IApril 15, 1968

adders or multipliers in series, each one working on

the result of the preceding unit. Thus, as the last

unit in the string starts work on its part of aprob-

lem, the first unit is several steps ahead of it.

Time/Data claims its method is simpler than

the Cooley-Tukey approach, which is based on a

set of nested multiplications.

Data by the block. The Time/Data machine can

accept analog data at frequencies up to 20 kilo-

hertz, which it promptly converts to eight-bit digital

words, or it can accept direct digital input at up to

200,000 words per second. The data is stored in

a core memory containing 4,096 18-bit words.

Time/Data's machine accepts data for one sec-

ond, provided neither channel takes in more than

1,000 samples. When data comes in faster than that,

only the first 1,000 samples are accepted before

the input is shut off; at the 200,000 bit/sec rate,

for example, the input is active for only 5 millisec-

onds and idle for 995 msec. But, in general, during

any one-second interval, the machine accepts one

block of data, processes the previous block, and

clears the block before that, in analog or digital

form. The Bell Labs' machine, on the other hand,

can accept up to 8,192 samples in as short an inter-

val as 8.2 msec; it could easily process 1,000 sam-

ples in 30 msec. There is a drawback, however:

the shorter the sampling interval, the poorer the

resolution of the output.

Sloane emphasizes that speed is not the only

important consideration. The Bell Labs' machine

must be used in conjunction with a computer that

actually collects the samples, perhaps multiplexed

from several sources. The computer requires apro-

gram to collect the data and transfer it to the proc-

essor, to fetch the Fourier coefficients after they have

been computed, and to transfer them to the outside

world. The Time/Data machine is a total system

that needs no computer, although it can be linked

to one if desired.

"We have a powerful analysis tool for signal

processing," says Sloane, "which can be used di-

rectly for awide variety of applications--biomedical

instrumentation, for example, or structural analysis,

antisubmarine warfare, acoustics, radio physics.

meteorology, and even astronomy."

A few extras. Outlook for the IBM development

is that it will follow the general approach of the

Bell Labs design, with perhaps a few added fea-

tures for speed. For example, the Bell Labs mul-

tiplier design, with a substantial addition of hard-

ware, could multiply two complex numbers almost

instantaneously. IBM's Federal Systems division is

working on a design in connection with a military

application; a commercial version may come later.

Sylvania's machine, like Bell Labs, is for research,

but the company may decide to market it later. It

was originally designed as a simulator to study ra-

dar signal processing and communication problems,

and is now being used to simulate modems (modu-

lators-demodulators) in military systems. In some

respects it resembles the Bell Labs machine, in the

techniques.it used to achieve high speed. But like

Time! Data's new computer, Sylvania's machine can

stand alone.

--Wallace B. Riley

Computers Editor

NUMBER OF OPERATIONS- MILLIONS

10 9 8 7 6 5 4 3 2

o
1 2 3 4 5 6 7 8 9 10 11
NUMBER OF SAMPLES-THOUSANDS
Startling improvement. Solid line shows number of operations required when computing with FFT, as compared with conventional form (dashed line).

efficient; stherefore takes on all values in the range 0 to N -- 1for each value of n, which also eventually covers the sanie range.
The coefficient of the first term is simply the average value of all the samples--their sum divided by N. Rather than omit the exponential multiplier, it is set to +1 by making n = 0. This is why nand s range from 0 to N -- 1 instead of from 1 to N. Equally important, this setting simplifies hardware implementation.
The process can be described as:

N-1

A(n)

=

1 N

f(s) exp (--j2rns)/N

Considering the workload
The computational effort depends on both the number of samples of the original function and the frequency spectrum that must be represented. Without the fast Fourier transform, these Fourier coefficients would have to be calculated for each frequency separately. Each coefficient would require the summation of N real and N imaginary quantities, each of which is the product of asample value and a trigonometric weight. In the case of a real function, only N/2 coefficients have to be calculated --those more than half the sampling frequency are complex conjugates of those below. Thus, a total of 2N .N/2 = N2 products would be required to compute the coefficients.
If a fine spectral resolution is required over a

Electronics lApril 15, 1968

127

large bandwidth, the number of computations could become very large. This is because the sampling frequency must be at least twice the highest fre-

even-numbered coefficients. Odd-numbered coefficients result from combining the coefficients of samples 1, 5, 9, 13, ...and 3, 7, 11, 15, ...

quency present in the signal, and the number of

Thus, each set of coefficients is the equivalent of

samples is proportional to the reciprocal of the fre- two subsets--derived from half the number of

quency resolution. Unless the sampling frequency samples. The ultimate subdivision of a single set restriction is adhered to, aspurious Fourier trans- of coefficients is N subsets, each containing only one

form will be derived from the samples, possibly coefficient that describes the waveform, but very leading to negative frequencies. This is illustrated poorly. These coefficients are none other than the

by stagecoach wheels in motion pictures which ap- original samples.

pear to move backward because the frame rate of

Reversing this process, then, the samples can

the film--the sampling frequency--is less than twice be combined into pairs, then quadruples, then

the frequency with which the wheel spokes pass a octets, and so on, until a single set of coefficients

given reference position. Their reverse motion cor- based on the entire set of samples is obtained. The

responds to anegative "spoke frequency."

procedure is iterative. The FFT'S speed comes from

Thus, to determine the power spectrum of asig- executing fewer operations, using this iterative

nal having abandwidth of 1,000 hertz with afre- procedure, on the sanie data that the conventional

quency resolution of 2hz, an analysis must have a Fourier transform uses.

sampling rate of at least 2,000 hz and a record

The process used to compute the nth Fourier co-

length of lh second, so that N = 1,000. For this efficient for aset of N samples is thus applied twice

case, the Fourier transformation requires the for- to alternate samples--once each to the odd-num-

mation and summation of amillion terms.

bered and the even-numbered samples. But this

Halving and doubling

time the multiplication is by exp( --j4rns)/N, instead of exp( --j2ens)/N, and the result for each

Basically, the FFT algorithm calls for combining half-set of samples is doubled. Then, multiplying

the Fourier coefficients for two interleaved sets of the half-result for the odd-numbered samples by

samples to yield the coefficients for the composite exp( --j2rn )/N, adding the even-numbered half-

set. Thus, the coefficients for the even-numbered result, and dividing by 2 gives the same result as

samples and those for the odd-numbered samples was originally obtained for the full set of samples, can produce asingle set of coefficients for all the for half the final set of Fourier coefficients. The

samples.

other half of the final set is obtained by subtracting

In the same way, coefficients derived from the odd half-result from the even half-result after

samples 0, 4, 8, 12, . .can be combined with coeffi- the multiplication.

cients from samples 2, 6, 10, 14 ...to produce the

These half-result operations are equivalent to a

X(0)

X 1)

X 2)

X(3)

X(4)

X(5)

X(6)

X(7)

FROM: A3(4)= A2(4)+A 2(5)W 1/8
SUBSTITUTING A1'S FOR A2'S A3(4).A1(4)tA1(6)W2431A1(5)+Ai (7)w 2,8]w 1,8

SUBSTITUTING X'S FOR AI'S

A3(4). X(0)- X(4)e8 +EX (2)- X(6)e81W2/8+ {X (II- X(5)1.7/0 1-[X(31-X (7)eqw2/13]w iíe

SINCE -MOW 0.X(K)W 8

AND weW bie

2,

3,

A3(4).X101W 8+x(11W8+X(21W' 8+X(31W·e+

X(4)W4/8+X(5)W5/8+X(6)08+X(7)V118

X(0)-X(4)W o, 13

X(11-X(51w 0,8

X(2)-X(6)W

Ai(4)

A1(5)

A1(6)

L

X(3)-X(7)e8 A1(7)

Lei Ai(4)i-Ai(6)W /8

Aii511-A i(7)W 2/8

A2 4)

A2(5)

Il t e-- W1',e

A3(4). A2(4)4-A 2(5)w 1/8
Working backward. Every sample is involved in the computation of any given output, yet without extensively duplicating the work. Equations at left outline the procedure and the substitutions that take place.

128

Electronics April 15, 1968

····4111 VI

single interleaved set, and can be expressed by
E N12-1
even: A.(11) = 2

For example, samples X(0) and X(4) are combined to get A1(0) and Ai(4):
Ai(0) =. X(0) + X(4)W°/8 = X(0) + X(4) A1(4) = X(0) -- X(4)W°/ 8 =: X(0) -- X(4)

The quantities A1(0) and A1(4) represent estimates

odd:

E N12-1

Al(n) = N

f(2s

1)W2"./N

of the d-c terna and first harmonic. The same mathematical procedure makes other estimates of the d-c and first harmonic from each pair of original sam-

8=0

ples, obtaining the four two-point transforms Ai(0)

These are for afixed value of n; the sample number s varies from 0 to N -- 1, and W stands for exp( --i2r). The magnitude of this expression is always equal to +1, but W is always raised to a fractional power, so that the multiplier is acomplex root of +1.
The two groups of Fourier coefficients are
A(n) = [A0(n) Ai(n)Wn/N]

through A1(7).
Pairs of two-point transforms are then combined to obtain four-point transforms A.(0) through
A.(7). Again, the arithmetic operations are similar, except that the spacing between pairs is halved, and different powers of W are used in the complex multiplications. The final step for an eight-point record determines the A3 terms that are the desired complex Fourier coefficients within a scale factor

A.(n -F --N2 = MA.(n) -- Ai(n)WoN]

of 1/8. Although the diagram shows only the real com-

where nvaries from 0to (N/2) -- 1. This process is repeated over and over for finer and finer interleaved sets until two sets are finally interleaved into asingle series.
This procedure is also applied to the half-sets of samples, by computing quarter-results on alternating quarter-sets. If N is apower of 2, this dissection process should occur logo N times, which would bring it down to the point where coefficients can be computed from individual samples of the original record.
Therefore, starting with N samples, each of which is a"series" with only one term, the equations are applied over and over again. Each iteration halves the number of series and doubles the number of ternis. This form of the algorithm is sometimes called decimation-in-time form. Other forms have been proposed--for example, one called decimationin-frequency.
An important consequence of this approach is that the results of each iteration can be stored in the same memory space from which the input to the iteration was taken--destroying the previous results. Another consequence: the final Fourier coeffi-

ponent computations, the imaginary components are computed concurrently with the saine procedure.
All of the eight-point Fourier coefficients may be obtained from this rather simple process, and the
components can be verified by working back through the process, as shown in the diagram on the opposite page. This computational procedure can be extended to transform data records of any length, provided the number of samples is a power of 2. For all cases, the calculations require logoN iterations. The first iteration uses W raised to the zero power, or simply +1, and later iterations use fractional powers of the coefficient. Each basic operation of the computation involves one complex multiplication, one sign change, and two complex additions. In general, for arecord length of N samples, each iteration requires N/2 basic operations. Thus, the entire process requires atotal of N/2 logoN basic operations, compared with N2 real multiplications when FFr isn't used. The graph on page 127 illustrates the dramatic effect FFT has on computational efficiency when N is large.

cients are not in consecutive order. The rearrange- The authors

ment of the coefficients, which follows a simple pattern, is nevertheless extremely difficult to program on ageneral-purpose computer. Indeed, half the execution time in atypical FFT program is spent

Richard Klahn, amember of the technical staff at Bell Labs,
has worked primarily on computer
organization and on antenna

on rearranging the final results, which involves

steering projects.

much manipulation and testing of index values.

Computing with FFT

A rather short record of only eight samples illustrates the principles of FFT. Because W represents
the complex exponential, it is found that W 0/8 .= +1 and W 4/8 = --1, and that Wom+ 0,8 -- W a/8 for any integer value of M.
The FFT computational procedure, one form of which is diagramed on page 125, first uses pairs of the original samples to obtain simple two-point transforms based on two of the original samples.

Richard R. Shively, also on the
technical staff, has been working on radar-signal processing and the
Nike X computer since 1963. He
has adoctorate from the University of Illinois, and was at IBM before joining Bell Laboratories.

Electronics April 15, 1968

129

Instrumentation
Making it in pictures

Electric field intensity can be mapped on presensitized Polaroid film; method is quicker, simpler, and more accurate than mechanical scanning

By Keigo lizuka
Harvard University, Cambridge, Mass.

The only way at present for engineers to map an electric field is to mechanically scan it, point by point, with a small probe. The technique has its drawbacks. It's time-consuming, recording isn't continuous, and the original field can be disturbed by the probe's lead wires and supports. Microwave holography would be asolution, but there's no convenient microwave analog to the photographic plate.
However, standard Polaroid film can do the job. This method, based on the temperature dependence of the developing process in uniformly exposed film, has proved to be inexpensive, accurate, and remarkably uncomplicated. A field's intensity can be mapped simply by holding the film in the field for less than aminute.
The Polaroid film is first presensitized by abrief exposure to uniform light. The developing process is started, and the film, still in its packet and shielded from light, is then placed in the microwave field.
The Polacolor Type 58 film employed here is normally used for taking 4-by-5-inch color pictures and consists of negative and positive layers and a developing reagent. The negative, the positive, and a pod of developer are pulled through the rollers of a Model 500 Polaroid 4x5 Land film holder. This breaks the pod and releases the viscous processing reagent in athin layer between the negative and positive.
The film starts to develop as soon as it comes into contact with the reagent. Immediately after the
The author
Keigo lizuka, now aresearch fellow and lecturer at Harvard's Gordon McKay Laboratory, holds an MSEE from Kyoto University. He also received amaster's degree in applied physics from Harvard in 1958, and aPh.D. from the same institution in 1961.

reagent is spread, the film is placed in the microwave field, where an image is formed on it.
The electric-field component in the plane of the film produces aheating effect in the exposed silverhalide grains by inducing acurrent in them. The temperature rises by an amount proportional to the square of the field intensity, and because of this, the thermal field produced in the film exactly represents the intensity distribution of the electromagnetic field. The localized heating in the grains leads to localized increases in the rate of diffusion of the developing reagent to the grain sites, thus speeding the chemical development in the heated portions of the film.
The developer is removed from the film before the normal developing time has elapsed. The film at that point holds avisible pattern corresponding to the field's intensity distribution.
The film's sensitivity to microwaves can be controlled in three ways. In the first, the pre-exposure temperature is brought down to a level ensuring
the maximum deposition of the silver-halide grains. Experimental results put this optimum temperature in the vicinity of 25° to 35°F.
To achieve this level, it's best to chill the film to the temperature of dry ice before inserting it into the microwave field, since the film is warmed by the ambient temperature during the exposure process. Care should be taken not to cool the reagent pod, however, because it solidifies at around 32°F.
Second, the color of the light to which the film is pre-exposed influences its sensitivity to microwaves. The film's emulsion-coated negative contains dyes of different colors in nine separate layers. The time required for the developer of one of these dyes to reach the surface of the negative depends on the distance between the dye and the surface.
If the negative is pre-exposed to light of awave-
length that allows only that dye lying closest to the surface to emerge, development time will be relatively short; light of a different wavelength, of

130

Electronics IApril 15, 1968

course, will cause alonger development time. Thus pre-exposure of the color film to cyan (blue)
light results in a longer development time than does pre-exposure through ayellow filter. In effect, the thickness of the diffusion layer can be controlled this way.
In practice, pre-exposure to yellow light would be used for stronger microwave fields, cyan-colored light for weaker.
A simple box camera can be used to pre-expose the film. The camera is aimed at asheet of white paper illuminated at 45° by two carbon arc lights (5,600° K); the incident illumination is measured
by Kodak Neutral Test Card. The intensity of light reflected from the card is about 50 foot-candles. To obtain the cyan color, the film is first exposed through a blue filter (47) for 1/10 second with a lens opening of F/9/5, and then through a green filter (61) for 1/5 second with the same lens opening as for the first step.
The third method of enhancing film sensitivity

is to place ametal reflector behind the film. This disturbs the original field, but the reflector permits maximum power dissipation of the microwaves in the filin by adjustment of the distance between it
and the film. Black-and-white Polaroid film Types 52, 57, 55
P/N, and 107 are also suitable, but their sensitivity isn't as high as the color type's. When only asmall area of measurement is needed; the eight-exposure color pack (3 1 /4 by 41/4 inches) is useful.
The method isn't limited to mapping electromagnetic fields. It should be applicable to the
recording of any physical phenomenon capable of generating athermal image. For example, the temperature distribution within the flame of acandle was successfully mapped by holding the film vertically in the flame. A distribution within the emulsion is generated, and this causes the film to form an "image" whose intensity is directly proportional to the flame's internal temperature dis-
tribution.

METAL CYLINDER

-.17mm FILM

Between the horns. The Young's fringe pattern launched from two horns at an angle of 90° to each other can be mapped on a film packet at 45° to each horn with respect to the incident waves.

Scattered field. Film is used here to record field from a metal cylinder 17 millimeters in diameter. The E field is polarized in the direction of the cylinder's axis.

HORN UNDER TEST,

-FILM

FILM

REFERENCE HORN
On the flank. Film is held against an edge of an Xband horn, parallel to the center axis, to map the horn's radiation pattern. The reference field is superimposed so that the distribution of the wave front can be observed.

L- BAND WAVEGUIDE
Covering the mouth. The field intensity distribution at the mouth of an open-ended L-band waveguide is recorded by placing a cooled film packet at that point.

Electronics April 15, 1968

131

this system saved one of our customers...

in nine * months

By the way, the average savings of all )ur customers is 8500.000. 670 Lofstrand Lane
Rockville, Ma-yland 20850 Tel. (391) 424-2900

132

Circle 132 on reader service card

model 130a automatic spectrum display & signal recognition system
Automatically scans and plots the 20 Hz to 1000 MHz spectrum in 18 bands in 2 minutes time--completely eliminating human error! la Automates entire interference sections of RFI/EMI specifications testing. · Accelerates electromagnetic site surveying; data completely reduced.
Permits fast scanning and plotting of attenuation measurements of filters, shielded enclosures and cases, and circuit cross-talk. If you want to save money also, ask for complete information on the Model 130A. Available for sale or rental. RFI/EMI technician accompanies all equipment shipped from WEI.
WHITE
ELECTROMAGNET/CS
INCORPORATED
Electronics April 15, 1968

Communications
Airborne military transceiver finds room in crowded spectrum

Through artful design that keeps intermodulation distortion extremely low, the ARC-104 transmits and receives high-frequency single sideband signals in 280,000 channels spaced only 100 hertz apart

By I.P. Magasiny
RCA Defense Communications Systems Division, Camden, N.J.

A newly developed high-frequency transceiver goes along way toward solving the critical problem of electromagnetic compatibility in airborne communications. It can send and receive 280,000 voice channels in the bandwidth older transceivers used for only 28,000.
Known as the AN /,`RC-104, and developed by RCA for the Naval Air Systems Command, the set can reject a signal as high as 120 decibels above that of the tuned signal and only 50 kilohertz away. These characteristics allow it to operate almost trouble-free in crowded communication areas where high-powered interfering signals are close by. Now in the production prototype stage, the
transceiver is still being improved. The ARC-104 can operate in asingle sideband,
frequency-shift-keying or amplitude-modulationequivalent mode, transmitting 400 watts at peakenvelope or continuous-wave power.
Such improvements are made possible by: ·Eliminating all variable tuning circuits ·Synthesizing all frequencies from stable, phase-
locked crystals ·Mixing with linear parametric amplifiers

The author

Irving Magasiny, manager of RCA's high frequency programs, has worked on the design of h-f single sideband equipment since 1965. He holds amaster's degree from the University of Pennsylvania and has worked with Teledynamics Inc., Philadelphia,
and with the Schaevitz Engineering Co., Pennsauken, N.J.

·Using the same mixer injection frequencies for both transmitter and receiver
·Gating out noise before it generates spurious signals.
The ARC-104's other features are also impressive. It tunes automatically to any of 280,000 channels in amaximum of one second, has amean time between failure of 7,500 hours, can be tested dynamically with built-in circuits, and can be taken apart and put back together in less than half an hour. Previous transceivers took as long as two minutes to tune, had mean times between failures ranging from 10 to 100 hours, and had no internal test
circuits.
A standard of excellence
One of the keys to the low intermodulation distortion and low spurious output in the ARC-104 is the extreme stability and accuracy of the synthesizer, which generates frequencies accurate to 1 part in 109 per day and 1part in 109 per month. This is achieved by using crystal oscillators and by phase-locking each to a single ultrastable crystal frequency standard. The synthesizer generates all frequencies either directly from the standard or from the oscillators.
Two types of circuits offered the high stability needed for the standard--either the Pierce or Meacham bridge oscillators. The former was picked because it did not require as close acontrol on the quartz crystal or as tight tolerances on circuit components. Because phase shifts within the oscillating circuit affect the oscillator's stability, components had to be carefully selected. To maintain stability in all weather and at all latitudes, the crystal is placed within asystem of double ovens. The inner

Electronics 'April 15, 1968

133

33 -38.9997 Mhz VARIABLE FREQUENCY OUTPUT [83-104.9997 Mhz

MIXER (-1

MIXER (-)

MIXER 1-i-)

MIXER (+I

MIXER 14-)

DIVIDER

DIVIDER .·10

10.3- 10.4 DIVIDER'710

MIXER (-I

FREQUENCY MULTIPLIER
IX 41
125 Khz SYNC. PULSE

MIXER (-)

MIXER 1-I-1

MIXER (+1

MIXER I- )

CRYSTAL OSC

44-54-64 Mhz

o --J

CC

Tyr o

CRYSTAL OSC 52.25-54.50 Mhz

CRYSTAL OSC 16.9-17.6 Mhz

CRYSTAL OSC 15.1-16.0 Mhz
M I7MIM.I.M

CRYSTAL OSC 13.7-14.6 Mhz

CRYSTAL OSC 16 0-16 9 Mhz
à1·«1111rall····\

10 Mhz

1 Khz

100 hz

oven keeps the crystal at atemperature that varies by no more than a few milli-degrees. The outer oven keeps the temperature surrounding the inner one constant. Amplifier feedback of 20 to 25 db was necessary for the stable gain needed to contról the oven temperatures. That feedback also insured immunity to noise within the amplifying loop and
A long time in port
Work on the ARC-104 goes back all the way to mid-1962 when RCA received a Navy research contract. In the following years, transceiver requirements and design approaches changed several times to take full advantage of the rapidly evolving technology. For instance, transistors were scrapped in favor of ic's and synthesizer requirements were upped from 1 khz to 100-hz frequency spacing.
Finally, RCA built several experimental models and tested them under the direction of the Naval Air Development Centér. Now RCA has started qualification tests of the production prototype.

protection against component variations. Temperature-compensated voltage-reference diodes are used throughout the amplifier, and d-c control is employed to avoid interference with synthesized frequencies.
The making of channels
Early versions of the ARC-104 synthesizer were digital, using bipolar or field effect transistors. Digital synthesizers lend themselves to circuit integration but at the frequencies required they weren't sufficiently reliable or stable resulting in jitter, microphonics, and spurious signals.
The synthesizer finally developed includes six decade oscillators; five of which have 10 crystals, and one has three. Decade oscillators correspond to the 100-hz, 1-khz, 10-khz, 100-khz, 1-Mhz and 10-Mhz digits of the 33 to 104.999-Mhz signal sent to the receiver and transmitter. A control signal from the tuning panel selects the appropriate frequency from each oscillator, which then locks on to the standard. Outputs arc incrementally mixed, repetitively divided or multiplied, then mixed.

134

Electronics 1April 15, 1968

Mhz corresponding to antenna frequencies from 2.0

21 Mhz

GEN 150 Mhz

3Mhz

280,000 oscillators. For high stability, the ARC-104 uses incremental synthesizer to generate all frequencies required for transmission and reception. The outputs of fixed-
frequency crystals, which are locked to the standard, are mixed, divided, and multiplied.

to 7.9 Mhz. Similarly, the -100-khz decade output mixes with the 10 Mhz-digit oscillator to ultimately produce outputs corresponding to antenna frequencies from 8to 29.9 Mhz.
To prevent spurious couplings in the mixers, oscillator frequencies were carefully selected in relation to each other and to the fixed frequencies generated by the synthesizer. Each decade oscillator operates in aslightly different frequency range
from the others. Despite precautions, the synthesizer's variable
frequency output is too high in spurious content and noise. Therefore, a phase locked oscillator in
the receiver section boosts signal-to-noise ratio and reduces all spurious frequencies more than 120

24 Mhz

CONTROL

I AME

1

db below the generated signals. Turned on

J1.75

Each crystal decade oscillator consists of the

( hi 12O Mhz 100 Khz SYNC PULSE

GEN 1.75 Mhz
73 25 Mhz

Mhz ·
73.25 --1Mhz

TO
TRANSMITTER AND RECEIVER

CONTROL

100 Khz RC SELF TEST

frequency selector, varactor controlled oscillator, sampling phase detector, and pulse shaper. Each section is designed to insure the highest accuracy and stability of synthesizer operation.
When afrequency is selected in the ARC-104, a
control signal is sent on the appropriate lead to one of 10 p-i-n diodes in each decade oscillator. This switches on the diode, placing the desired

crystal, bias network, and frequency-centering inductor in the circuit. Diode on-impedance is less

GEN 100 Khz 125 Khz

· 125 Kh

TO RECEIVER TO RECEIVER

than 10 ohms while its off-impedance is 10,000 ohms, thus insuring that all crystals except the one operating are completely out of the circuit.

The oscillator section includes two amplifier

stages with feedback. It functions only when alow

FIXED FREQUENCY REFERENCE SIGNAL GENERATORS
3 Mhz FROM STANDARD FREQUENCY
Both the receiver and transmitter in the ARC-104 use fixed frequencies of 1.75 and 29.25, and 73.25 Mhz for frequency translation, modulation, and demodulation. Crystal filters reduce spurious signals 120 db below these frequencies. The synthesizer itself uses internal local oscillator signals at 105 and 120, and 75 Mhz.
To generate decade frequencies, the synthesizer mixes the output of the 100-hz decade oscillator with the 120-Mhz signals then divides it by 10. The resulting 10.3 to 10.4-Mhz signal mixes with 105 Mhz, providing the local oscillator-injection signal for the 1-khz decade oscillator. Each successive divide-by-10 operation reduces the controlled frequency increments by 10. Crystal frequencies in the synthesizer are actually separated by 100 khz but frequency division by 1,000 (three divide-by10's )achieves the desired 100-hz frequency spacing

impedance is inserted in the emitter of the first stage. The inserted impedance consists of avaractor diode in series with the p-i-n diode, the crystal, and the center-frequency inductor. Thus, the emitter impedance is low only at the series-resonant point of the selected crystal. The varactor acts as
the control in the loop, locking the crystal to its
correct frequency. At the same time that the control signal is sent
to acrystal, asynchronizing pulse derived from the frequency standard and the pulse generator is transmitted to a blocking-oscillator, which shortens the pulse and sharpens its edges. -
Finally, the shaped pulse closes a switch in the sampling phase-detector section of the oscil-
lator, thereby connecting the oscillator output of the selected crystal frequency to acapacitor. The voltage is stored on the capacitor until the next pulse, and is also delivered to the varactor, which controls the crystal oscillator frequency. Varactor frequency control simplifies filter design, increases the ratio of capture to lock-range, and reduces the frequency modulation caused by ripple.

required in the transceiver. The output signal of the 100-khz decade oscillator
mixes with 1-Mhz increments derived in a similar manner from the 1-Mhz digit crystal oscillator, producing alow-band synthesizer output of 33 to 38.9

Receiver dynamics
The ARC-104 owes its ability to detect both strong and weak signals--even when high-power interfering signals are close by--to the high linearity

Electronics April 15, 1968

135

HIGH TEMP FREQUENCY COMPENSATION

INNER OVEN
-OH RYSTAli

HTR SENSOR

INNER OVEN
PROPORTIONAL CONTROL AMPLIFIER

OSCILLATOR

AMPLIFIER

REGULATED 25v TO INNER OVEN AND ALL CIRCUITS

VOLTAGE REGULATOR

30 v

TO OUTER OVEN

DIVIDER

AGC
OUTER OVEN PROPORTIONAL CONTROL AMPLIFIER

-1-,1 CRYSTAL
Fl LTER

gir
AMPLIFIER FILTER
a PRESENCE
DETECTOR

OUTPUT
--m. 3 Mhz TO SYNTHESIZER

--o.

BUILT-IN TEST
DETECTOR OUTPUT

-- NVV-- SENSOR

HEATER

OUTER OVEN

Stable generation. Frequency standard controlled by dual oven system is one key to ARC-104 linearity.

of its front end. A double-superheterodyne detection technique makes use of parametric amplifiers to convert r-f signals to higher intermediate fre-
quencies. I-f signals are then passed through highly selective crystal filters to bring spurious signals down at least 120 db below tuned signals.
A varactor parametric up-converter is the only device now made with the linearity and noise figure

needed for the first mixer in the ARC-104 receiver. Because the voltage versus charge relations of the
varactor diode is an almost perfect square-law function, input and injection signals produce only d-c, the fundamental input frequency, sum and
difference frequencies, and second harmonics. Other mixer products are virtually nonexistent. Dynamic range is also helped by the varactor's

FILTER
FILTER ANTENNA
FILTER
FILTER
FILTER FILTER

HIGH BAND PARAMETRIC AMPLIFIER 8-30 Mhz
PUMP AMPL 83-105 Mhz
PUMP AMPL 33-39 Mhz

CRYSTAL FILTER 75 Mhz
FILTER FILTER

LOW BAND PARA
AMPL 2-8 Mhz

CRYSTAL FILTER 31 Mhz

75 Mhz I-F

MIXER

73.25 Mhz

IN FROM

SYNTHESIZER

1 NOISE

**- NOISE BLANKER

BLANKER J

GATE

FCIRLYTSETRAL I.75Mhz

·11.·11111,
1.75 Mhz I-F AMPL

29.25 Mhz IN FROMoSYNTHESIZER

31Mhz I-F

MIXER

1.75 Mhz IN FROM o SYNTHESIZER

I&SIANMGLPELISTIUDDEEBAND MODULATED EQUIVALENT
DETECTOR

AGC

PUMP LEVEL CONTROL

HIGH BAND 4
VCO
LOW BAND -VCO

PHASE DET

AMP a
FILTER

AUDIO OUT

HI LO

INPUT FROM SYNTHESIZER 33-39 Mhz; 83-105 Mhz

SWEEP CIRCUIT

Receiver combination. Parametric up-converters and noise-blanking techniques keep spurious signals down.

136

Electronics IApril 15, 1968

ability to handle strong signals without breakdown and low signals without adding appreciable noise
or attenuation. A low noise amplifier pumps the varactors in the
parametric device with amaximum 2-watt injection signal. Pump control is derived from an automatic level control circuit and automatic gain control detector (age). The automatic level-control circuit
reduces the pump signal power if it exceeds the maximum required level while the age detector reduces the power if the intermediate frequency signal level increases. The i-f rejection filters eliminate pump noise amplified at 31-Mhz or 75-Mhz.
Input signals to the receiver section of the ARC104 are selected with the help of eight bandpass filters, which eliminate the need for electrically

sistor oscillators (one for the low band, the other for the high band), a phase detector, a directcoupled amplifier, acompensating network, alowfrequency sweep generator, and a sweep-inhibit and gate circuit. The sweep circuit tunes the oscillator so that it sweeps past and locks on to the synthesizer signal. The sweep-inhibit-and-gate cir-
cuit isolates the oscillator from interference. In the first i-f section of the receiver, low band
signals (2 to 7.9 Mhz) are converted to 31 Mhz, high band signals (8 to 29.9 Mhz) to 75 Mhz. Signals in either band are then converted to asecond i-f frequency of 1.75 Mhz, and passed through a
noise-blanker gate and crystal filter. The noise-blanking circuit, together with the
parametric mixer, contributes in large ixtrt to the

FVTOSEIKSCTE CONTROL AMPL MBOADLJALNACTEODR ICFRIYLSTTEARL SSB GENERATOR TCHLIRPESHOAL'D

CFRIYLSTETRAL

175 Mhz 'COGANAMTTEREOL PFLAACORUEOMWOTVNPEMOETLRtMLRAOTALIMCPL AMPL

GPSGAOIATDWTEEEERCT4OONNATEMRPOLL FROM e-TSRIOEDNCEEEIVTEOR

1BMIAXL2EA9RN.42C5EDMhz . . .1BMIAL7XL3E.A2RN5CEMDhz

AMPL FREQUENCY

S1Y3CF.N1IR7T5LYMHTS4MhEEThzSRAzILZER

MIXER 33.39 83-105

FREQUENCY TRANSLATOR

MMhhzzCONTROL

LOW BANDMhz 2-7.9999 HIGH BANDMhz 8-29.9999

AMPL r AT24TSOEMEW3SLP0PTFLOPMWEhPEzR INTERMEDIATE POWER AMPLIFIER

The way out. Transmitter exciter is broadband, untuned, low-noise, and low spurious signal circuit.

or mechanically tuned tracking circuits and also simplify remote control. The filters are designed so that the ratio of maximum- to minimum-passband frequencies is limited to 11/ 2 :1, thereby keeping the second harmonic at least 120 db below that of the input signal. The injection signals are far enough away from the passband frequencies so that they're sufficiently attenuated. After the appropriate band has been selected, signals can be tuned in precise 100-hz increments merely by
changing the first injection signal. Before mixing with the received signals, the
variable frequency injection signals are processed in abuffer circuit, which improves their signal to noise ratio to greater than 40 db. This "clean up" circuit is composed of two voltage-controlled tran-

ARC-104's ability to operate in areas of high manmade and natural noise. The spectrally pure injection signals also minimize spurious output from the transmitter. The noise blanker recognizes impulse noise and gates it out of the circuit for about 800 microseconds. This prevents transients from ringing the 1.75-Mhz crystal filter.
The pulse-detection circuit bypasses the first
i-f filter and has much greater bandwidth. It recognizes impulse noise varying in intensity from 100 microvolts to 1volt. An lc, logarithmic amplifier with 70-db gain at 1Mhz enables weak pulses to be detected. Once the pulse is detected, it triggers a flip-flop that generates an 800-1£pulse, tuning off the diode gate preceding the 1.75-Mhz filter.
Because the logarithmic amplifier is broadband,

Electronics April 15, 1968

137

Report in 4 Seconds
Because the ARC-104 is designed to operate in aircraft, it's also designed to diagnose its own troubles, simplifying maintenance. Aided by detectors and indicators in each functional module, a test module consisting of 75 integrated circuit flatpacks allows an operator to quiz the set on its performance and get a report in four seconds. The module sets a magnetic latch indicator on the control panel if there's trouble and pinpoints the fault by also setting an indicator on the defective module.
Dynamic tests at any channel frequency in 100kilohertz increments and in any operating mode are made on all parts of the transceiver. Fault indicators stay set even with power removed, requiring no current. They can be reset only by taking out the defective module. However, they don't have to be reset for the transceiver to continue operating.
During the tests, a1,500-hertz signal applied to the exciter input produces a400-watt peak envelope power signal that is dissipated in an internal 50-ohm carbon-resistor load. Output of the intermediate power amplifier, power amplifier, and power supply are checked by comparison with reference voltages.
While the exciter is being tested, its modulated 1.75-Mhz i-f output is used to check the receiver's second i-f and audio circuits. And an amplitude modulated r-f signal derived from the synthesizer's 100khz generation and the 1,500-hz test signal connects to the receiver input. The receiver functional assembly has three fault indicators: for the synthesizer clean-up circuit, the front end, and the second i-f and audio circuits. Additional fault isolation down to individual circuit boards can be made.
it is vulnerable to jamming. To prevent unwanted noise blanking, the pulses generated by the flipflop are counted and if they occur more than 75 times asecond, aSchmitt-trigger circuit prevents them from reaching the diode gate. The Schmitt circuit doesn't allow the gate to open the signal circuit for more than 10% of the time.
Message center
Like the receiver, the ARC-104's transmitter exciter is abroadband, untuned, low-noise and lowspurious signal circuit. It accepts data or voice signals either from microphones or from military intercommunications sets such as the AN/AIC-14 or AN/AIC-25, producing either asingle sideband, amplitude modulated equivalent, or frequencyshift-keyed signal of 2-watts-peak envelope power. Making up the exciter are a single sideband generator, frequency translator, and intermediatepower amplifier.
In the single sideband generator, voice, fsk, or test signals are gated through acircuit with ±-.10 db of adjustable gain. Then the signals are amplified and modulated onto a 1.75-Mhz carrier with the carrier sideband removed. If amplitude-modulated equivalent transmission is used, the carrier is reinserted.
Part of the i-f signal goes to an antomatic level

control amplifier and then to the frequency translator; part is gated off by adiode and is sent to the receiver i-f as a side tone that tells the operator whether the transmitter is operating properly.
In the translator, the modulated 1.75-Mhz carrier mixes with either a29.25-Mhz injection signal (for transmission in the 2- to 7.9-Mhz band) or a73.25Mhz signal (for transmission in the 8- to 29.9-Mhz band). The low band i-f, 31 Mhz, and the high band i-f, 75 Mhz signals, are then filtered, mixed with the selected injection frequency that assigns them to achannel, amplified, and sent through abandselector gate to the intermediate-power amplifier. Using the same injection, frequencies in both receiver and exciter minimizes coupling and spurious signal generation.
In the exciter's final section, the intermediatepower amplifier boosts all signals to a2-watt-peak envelope power level. Linear broadband amplification over the 2- to 30-Mhz band is attained in three stages by using negative feedback and broadband transformers that match impedance and couple the stages. The first two stages use ahigh-frequency overlay silicon power transistor (2N3375) and the third stage uses asimilar transistor (2N2876).
Getting on and off the air
The last link in the ARC-104 is abroadband untuned, linear power amplifier that delivers 400watt-peak envelope or c-w power with only 35 db intermodulation distortion. Spurious signals and noise are down 90 db. This is achieved by using broadband-output coupling transformers, a single 750-watt linear output tube, and an antenna filter. The tube was designed for high transconductance, low input capacity, and low peak grid-drive level requirements. It has ahigh thermal conduction anode that forms alow-resistance path to the amplifier's heat exchanger. The base plate supports the amplifier and serves as aheat sink.
There are eight broadband output transformers, one of which is automatically selected by arotating bandswitch operated from the transceiver control panel. The transformer output then passes through a low-pass filter before transmission to remove spurious as well as second and higher harmonics. Power output is limited by the exciter's automaticlevel-control amplifier, which is controlled by the transmitter output detector and adjustable threshold circuit.
Mounted with ablower, the ARC-104 set meets military Class 1A requirements--it can operate up to 35,000 feet altitude over atemperature range of --55°C to +55°C. Mounted without blower and cooled from an external system, the set meets Class II specifications--it can operate up to 70,000 feet altitude over arange of --55°C to +71°C.
RCA has taken steps to obtain an output of 1-kilowatt-peak envelope power and c-w using a single tube. Another version of the transceiver permits twin and independent sideband operation with fsk or phase-shift keying multitone data as well as voice.

138

Electronics April 15, 1968

Go ahead. Take hold of

the newest woo pf hvoltage

vacuum fixed cap

for

induction heatm

This is the actual size (6 1/2 x31/4 )of the largest of two new unique vacuum fixed capacitor series from ITT Jennings. They were spe-
cifically designed for use in induction and dielectric heating equipment operating from low frequency
through high frequency. Especially benefitted will be, such applications as crystal growing, zone prccessing,
rf sputtering, plastic sealing plastic preforms, and glue-line drying.
The result is the most outstanding combination of
capacity, voltage and size ever created, and the greatest dollar value per KVA for plate blocking and tank circuit use.
This new CFSB series is characterized by high

th ,·eramic and

Capacity

construe:ion, very low s, and low internal inductanze. Pertinent specifications include:
5000 or 10,000 pf

Peak test voltage (60 Hz)

10, 15 kv

Current rating (16 MHz)

95 amps rms

(1 MHz)

200 amps rms

Dissipation

Ls than 10 x

Internal inductance

Less than 10 nanohenries

You can find capacitors much bigger, but none

better; the potentialities ir both replacement and new

design are obvious. For detailed information, write for

Catalog No. 101. ITT Jennings, a division of Inter-

national Telephone and Telegraph Coiporation, 970

McLauchlin Avenue, San Jose, California 95108.

ITT JENNINGS

Electronics lApril 15, 1968

Ci -cle 139 on reacer service card

139

Our story starts with avery superior polyester film.

To which we add exceptional dimensional stability.

The best dimensional stability of any polyester film. An independent testing lab,
DeBell &Richardson, Inc., tested calibrated lengths of Celanar and other polyester films at temperatures from 73F to 120F for over 24 hours. When measured, other films showed up to 77% greater thermal
expansion than Celanar film.

140

Electronics IApril 15, 1968

And greater strength.
Celanar is the strongest balanced biaxially oriented plastic film commercially available.

And insulation resistance.
An outstanding property of Celanar film is its high insulation resistance over awide range of temperatures. Celanar has superior electrical properties, including excellent dielectric strength, dielectric constant and dissipation factor. Good reasons why Celanar is widely used as an insulating material in electrical insulation applications.

To bring you Celanar Film with a combination of properties unsurpassed for electrical uses.
Celanar polyester film offers abalance of electrical, mechanical, thermal and chemical properties that make it your best choice for applications from flexible circuits to wirewrap.Want proof? Just mail the coupon.

Celanese Plastics Company Dept. 133-D, P.O. Box 629 Linden, N.J. 07036
Yes, Iwant all the facts about Celanar film for electrical applications. And send me a FREE set of gratings printed on Celanar. (Laying one on top of the other produces Moiré patterns that confound the eye.)

Name Company Address City

Title

State

Zip

Electronics IApril 15, 1968

CELANESE
PLASTICS COMPANY Celanese@ Celanar®
LCelanese Plastics Company is adivision of Celanese Corporation.

Circle 141 on reader service card

141

NEW CORNING C3 Resistor.

Small.
RN 50/RCO5 size. Clean lead length .150". Diameter 0.066" maximum. Put more per board. Stable.
The proven, long-term stability of CORNING Glass Tin Oxide Film Construction. Rugged.
Leads are beefy .020" dia. Eliminate handling and automatic insertion problems.

Terminated.
With reliable cap construction, not just soldered. Performs.
Power ratings to 1/8 watt, 70°C. T.C.'s of 100 and 200 ppm. Values from 10 ohms to 150 K. Tolerances of 1, 2, 5and 10%. Handy.
Leads are 1,2" for easier handling. Reeling is available.

Corning Glass Works
Electronic Products Division Corning, N.Y. 14830

Centlemen: D. Please forward data on new C3 Resistor. LI Please send samples of new C3 Resistor.

Name Title Firm Address City--

State--

CORNING
ELLCTkONICS

Circle 143 on reE...d.:e service card

Bounceproof... Chatterproof... Tamperproof... Dustproof... Moistureproof...
our mercury-wetted relays are even goofproof!

Magnecraft mercury-wetted reed relays completely avoid contact erosion, bounce and chatter. That's because pre-adjusted contacts and a pool of mercury are hermetically sealed within an atmosphere of high pressure hydrogen in a glass capsule. Hermetic sealing also provides protection against dust, corrosive fumes, moisture and tampering. And, there's no maintenance. You can even store them indefinitely without deterioration.
There are 195 stock Magnecraft mercury-wetted and dry reed relays available in many styles as well as in the MPC Modular Package shown.
You can rely on Magnecraft to fill all your relay needs from our vast supply of 444 different stock relays including general purpose, telephone and power relays. All quickly delivered and at competitive cost. Just ask our customers.

,\. or REED AND NMERCURY WETTED CONTACT MAU
FREE! Designers'
Reed Relay Handbook Yours for the asking.

Manufacturing Stock Relays for Custom Applications
Magneurfall(rt ELECTRIC COMPANY

5575 NORTH LYNCH AVENUE · CHICAGO, ILLINOIS 60630 · 312 · 282-5500 · TWX-910-221-5221

144

Circle 144 on reader service card

Circle 145 on reader service card-3-

As a result of new electrolytes and improved oxide film forming techniques, Extended Temperature Range Aluminum Electrolytic Capacitors are now available from CDE.

They feature Capacitance and DF stability, low CC leakage currents, high ripple current ca-
pability, and rugged design for
stringent vibration and shock endurance.
Five types are now available (and moretocome): UHT ... (-55 to +150° C), UHL...( --55 to

+125°C) UHR...(-55b+105° C) HNLH...(-80 to +110e C), and UFH ... (-55 to +105" C).
CORNELLDUBILIER
50 Paris Street, Newark, N. J.

For units available foryturdesign considerations, see following pa ge.

To 150°C
Featuring the exclusive CDE continuous cold weld connection of section to rod...insuring superior mechanical and electrical reliability. With far superior ESR to Temperature characteristics.

And with high ripple current capability, low DC leakage,Capacitanceand DF stability, Low impedance, rugged design for vibration and shock endurance.

EFFECTIVE SERIES RESISTANCE (ohms)

TYPICAL EFFECTIVE SERIES RESISTANCE (ESR) VS. TEMPERATURE FOR A 150MFD-25VDC CAPACITOR

10 9 8 7 6

4

3

..--

2

CONVENTIONAL ALUMINUM ELECTROLYTIC CAPACITOR

NEW HIGH TEMPERATURE CDE TYPES UHT AND UHL ALUMINUM ELECTROLYTIC CAPACITORS

NEW EXTENDED TEMPERATURE CDE TYPE HNLH ALUMINUM ELECTROLYTIC CAPACITORS

p

UHT 150 Ç UHL 125 C

O --80 --60 --40 --20

0 20 40 60 80 100 120 140 160

TEMPERATURE (centigrade)

These units are now available for your design consideration:

UHT

Miniature Axial Lead Case Sizes: 3/8 x
1516 to % x 211/18". Ratings: 3 mfd to 100 mfd, from 3 VDC to 100 VDC.

--55 to +150' C OPERATION

UHL UHR

Miniature Axial Lead Case Sizes: 9/32 x 15/16 to % x 211/18". Ratings: 3.3 mfd to 1000 mfd, from 5 VDC to 200 VDC, designed to meet and exceed Mil C-39018/1. (Already stock standards on our Distributor's shelves.)
Large Axial Lead Case Sizes: % x 11/8 to 1" x 3%". Ratings: 10 mfd to 12,000 mfd, from 5VDC to 200 VDC, designed to meet and exceed MIL C-39018/3. (Also available in --55 to +85 ° C specifications).

--55 to + 125° C OPERATION --55 to + 105° C OPERATION

HNLH

Miniature Axial Lead Case Sizes: 1/4 x % to % x 11/2". Ratings: 1 mfd to 600 mfd, from 3 VDC to 150 VDC. (Already stock standards on our Distributor's shelves.)

--80 to +110' C OPERATION

UFH

Computor Grade Case Sizes: 1% x 21/8 to 3" x 8%". Ratings: 5500 mfd to 300,000 mfd at 5 VDC 240 mfd to 9000 mfd at 150 VDC.

--55 to + 105° C OPERATION

For your design considerations, ask for details from your local CDE Sales Engineering Office. Or write:

CDE

cDouRBNILEILELR-

50 Paris Street, Newark, N.J.

In hope of doing each other some good

CO 2 laser windows
This Brewster-angle window in this CO., laser we own is made of KODAK

IRTRAN 4Optical Material. So are many other people's CO., laser windows. There are also some CO2 laser windows
made of IRTRAN 2 Optical Material. That's cheaper but absorbs a bit more at 10.6u. Many such windows are made of optical materials which are still cheaper and can remain as clear as IRTRAN 4Material. One of those needs only awindow-cooling system to keep
the absorbance down, but that can complicate design. The others likewise absorb no more than our stuff does and require no cooling either. Unlike ours,
they can deteriorate by absorbing moisture from the air.
What's picked depends on what's important.

This particular window shows no damage after passing 100 watts/cm2 over a 1cm free aperture for 20 minutes of continuous-mode operation. We suspect that's peanuts compared with the energy that others are pushing through their Irtran windows. If so, they are not likely to tell us their purposes, but if they didn't need Irtran material they wouldn't use it, and if they weren't getting their money's worth they surely wouldn't keep that asecret from us.
To ask questions about KODAK IRTRAN® Optical Materials, phone 716-325-2000, ext. 5166, or write Eastman Kodak Company, Apparatus Division, Special Products Sales, Rochester, N.Y. 14650.

More than taking apicture
There is considerable difference between taking apicture and using photographic instrumentation to extend the observer's senses and perceptions. Except for certain special cases such as sports photography and the photographic part of lunar orbiters, we have chosen to leave the instrumentation manufacture to others. We make the film. Mostly this means 16mm, 35mm, or 70mm film. (Aerial cameras are something else again. Some of them run on 70mm film, but generally they want something wider.)
A certain amount of instrumentation photography still aims at a pleas-
ing picture, it must be admitted. The rest of it just operates with the concepts that grew up around that aim.

The skilled practitioner in photograph-
ic instrumentation is assumed, how-
ever, to have learned more than what's covered in the basic photographic
theory course. And we make him some films based on that assumption--three rather new ones, in particular. They are fast films.
Processed for normal pictorial photography, they provide a choice of gamma--the classical measure of pho-
tographic contrast--of 0.65, 0.70, or 0.85, with a speed of ASA 1000 or slightly higher. Unlike the films of yes-
teryear, these are designed to do more than simply increase contrast with more development. In these the speed can
also be raised. In one of them it can be raised all the way to 8000 if the sub-
ject can stand agamma as high as 1.7.

Mind, we are speaking here not of just taking a picture at Exposure Index 8000 but of data captured by the hundreds or thousands of feet at E.I. 8000.
Whoever can figure out in advance whether his subject can stand agamma of 1.7 is entitled to regard himself as pretty hot in photographic instrumentation. He far more than qualifies to receive our chart that shows which films can be adjusted to which speeds and which gammas and how. He has hut to make his wishes known to Eastman Kodak Company, Instrumentation Products, Rochester, N.Y. 14650.
He might also wish to request Pamphlet P-29. It describes many other 16mm, 35mm, and 70mm black-and-white and color films and their various spooling specifications. Its chief attraction is not completeness (an unrealistic goal) but that it is mercifully thin.

Hard, shining mask
Your v, lie may think it odd that your company bought you this little mirror in amolded plastic case and paid more than she paid for the compact she carries in her purse.
And why are you washing it? -<--Circle 146 on reader service card

You wish to remove an accidental thumbprint. The thumbprint is on a
surface of chromium 0.06 ± 0.01 micron thick. Soap and water clean this chromium. Neither washing nor thumbs abrade it. On each and every one of these plates an attempt is made in our
factory to abrade it intentionally. If you are going to abrade it when using
it as a photomask for IC's, MSI's, or LSI's, we might as well abrade it first. Nothing happens, except that hidden
defects may show up. If more than ten defects show up over the 13/4 -inch
square central area of a2" x 2" plate, it doesn't leave our door. Actually no more than 5% of those we release have more than six defects, and half have none at all.
This new KODAK Metal-Clad Plate
C also comes in 21/2 "x 21/2 ", 3" x 3",

and 4" x5". To find out about our defect tolerances for those sizes, just ask. We don't find it necessary to pack in inert gas. We can find no effect on etch time after one year of storage in atmosphere.
For etchants and apositive-working
photoresist to put on this plate, you are on your own. You'll hear from us when we have something better to offer along those lines than what is currently on
the market. It is in that little mirror that we shine right now. Even for lines and spaces down to one micron, de-
pend on our dull, laborious dedication to quality. It pays off.
Details from Industrial Photo Methods, Eastman Kodak Company, Rochester, N.Y. 14650. Ask about KODAK MetalClad Plate N if you need that same quality with a negative-working photoresist over the chromiunz.

EASTMAN KODAK COMPANY An equal-opportunity employer

147

Chart yourself a foolproof le shield:

If you want to shield...

Fuse

Metex Porcupine Metalastic.' Its many contact points make this an ideal gasket for RFI/ EMI. Silicone rubber
provides a pressure and moisture barrier.

Metal boxes
with flat mounting surfaces (no sealing
problem)

Metex double round, single fin mesh strip. This is provided in many different metals · and sizes.

use

Metex Feltex material. Designed for wave guides, specifically provided for either pressurized or
non-pressurized systems.

Electronic equipment
(and cool it, too) /·····

Fuse

Metex Cool-Shield honeycomb panels. It's designed to meet specific attenuation requirements over specified frequency ranges. Many standard sizes and materials are available.

QUICKLY

call

(201) 287-0800 for 48-hour premium service (for your rush rush requirements)

148

For Free Samples, Prices and Literature on any or all of these RFI shielding materials--or for technical assistance on your particular requirements--write:
Circle 148 on reader service card

METEX Corporation
970 New Durham Road, Edison, N. J. 08817 (201) 287-0800 ·TVVX 710-998-0578
West Coast ·Cal Metex Corp., 509 Hindry Ave ,Inglewood, Calif
Circle 149 on reader service card-->-

lets you specify some great shapes in etched flexible flat cable...

-.4111111

alle""> ,r,eterne
-44411
--41111.11htibe

...4111116m>e

2eegge eZer·

4Peeee

ee-Nor-

and helps you put some new twists in the continuous kind

When your conductor system requires acircuit with

demanding electronic systems. And termination poses

three dimensional routing in a flat medium, or when

no problems. The flat cable conductor itself can be used

your point-to-point wiring must exhibit simple or com- as the mating element, or the conductor may be mated

plex flexibility in aflat plane, or both --specify Hughes

with almost all existing circula- or rectangular electrical

Contour"' Cable for the most advanced electrical inter- connectors. ·Regardless of your circuit problems, our

connection systems available. ·Hughes flexible etched
e flat cable designs and flexible flat continuous cable con-
figurations are practically endless. They give you

application engineers can help you with specialized complete wiring interconnection systems for all military,
industrial, or commercial applications. For engi-

adesign freedom and reliability unequalled in

neering help or information contact Hughes Air-

the industry, as well as answering all re- r

, craft Company, Connecting Devices, 500

quirements of light weight, cense wiring sys-

HUGHES

; Superior Ave., Newport Beach, Calif. 92663.

tems and exact reproducibility in the most L_

J Phone 714-548-0671, TWX 714-642-1353.

1111(1.11 , Alf!CRAI I C , MPANY

HUGHES CONNECTING DEVICES

HUGHES CIRCUIT lECHNOLOGIES - Connecvir Devices · Contour Cable" · Semiconductors · Flip Chips/Equipment · Frequency Control Devices · Microelectronic Circuits · MOSFETs

COMPONENT CAPSULES

General Electric VTM's develop over 500 watts to give you abetter
ECM device

Highest volumetric
efficiency at half the size--with GE
wet slug capacitors

Alnico 5-7 magnetic material--a great improvement over
Alnico 5

Specify Volt-Pae variable transformers for maximum life,
minimum maintenance

Bonded heater version of popular 7077/7486 tube now available

No other electronically GE 69F900 wet slugs meet

tuned device on the mar- high-density application

ket today can match GE needs with highest volu-

Voltage Tunable Mag- metric efficiency of any

netrons for power output capacitor. We halved the

(over 500W) and conver- military (CL64) wet slug

sion efficiency (to over size, and essentially kept

70%).

its electrical and per-

Magnetic shielding vir- formance traits.

tually ends degaussing

The 69F900 has excellent

effects in GE VTM's. capacitance retention at

Tube/equipment inter - low temps .. .can be

GE Alnico 5-7 improves or equals performance of conventional Alnico-5 --with reduced magnet length, smaller cross-section.
Alnico 5-7 has great advantage where space and weight must be minimal, and high demagnetization resistance is required.

Construction is the key The new GE16411 may

to Volt-Pac's optimum solve your most perplex-

performance. Here's why. ing oscillator problem.

A spring-loaded, grain - This small planar triode

oriented carbon brush provides low levels of os-

means even contact, re- cillator side-band noise.

duced wear. Self-lubri- A bonded heater addi-

cating nylon bearing les- tion makes the GE16411

sens voltage selector fric- useful under high shock,

tion.

vibration conditions.

Here are more fea-

GE16411 recently made

tures--Polyesterimide in - possible significant im-

Manual uncased unit, exposed terminals

Actual size

EOC
303 .po
100

EFFICENCY--· OvIc= EWE,.
--E51.1

-- i71;07111 --COY ESPICIIIIICE

--4000

man POIECI1,71· OPECATICII ELEE TECIE·OECT OECIo0100.

5

0 /100

% CO 3100

Sam

3300

o Ceti

face problems are minimal--each VTM can have an integral isolator designed for your system.
Airborne application features are: linear electron ic tu ning, rapid mod ulation, minimal power variation over the band, temperature compensation, and light, compact packaging.
GE VTM's are offered in low-, intermediate-, and high-power configurations for other microwave applications. Circle Number 231 for more details.

stored to --65C. Operating range is --55C to +85C. It's tough too-- withstands vibration to 2000Hz; 15G acceleration!
GE's new capacitor is fully insulated; has low, stable leakage current. Ratings areavailable from 6to 60 volts; capacitance ranges from 0.5 to 450

RATING

CASE SIZE

UME

50V, 30pf

solid (C512)

.341 X.750 100%

wet slug (CL64).281X.681 58%

69F900

.145X.600 15%

15V, 80µ1

solid (C512)

.341X.750 100%

wet slug (CL64).281X.681 58%

69F900

.145X.6150 15%

6V, 1801rf

solid (C512)

.279X.650 100%

wet slug (CL64).281X.641 100%

69F900

.145X.600 25%

* Recent developmental model

Circle Number 232 for more data.

· zR
sz,,

KO

ECO

NC

COO

PE CIACIECTICING

W esel, OE/

e

Demagnetization vs energy output, Alnico 5-7

Typical applications for Alnico 5-7 are high-density meter movements; electron tube devices; compact loud speakers; motors and generators.
Let our engineers work with you to design a Cast Alnico 5-7 magnet for your application. Circle Number 233 for technical and ordering information.

sulation of coil windings gives extra reliability. Aluminum radiator and base evenly dissipate heat, extend life. Goldplated track reduces possible heat build-up at brush contact, minimizes burn-out risks.
A-c voltage range of these autotransformers is zero to 100%, or 117% of fixed-input voltage without waveform distortion.
Manual or motor-operated Volt-Pacs can be ordered with or without enclosures, and with exposed or covered terminals. For more Volt-Pac facts, Circle Number 234.

provement in short-term, long-term stability characteristics in aspectrum analyzer design.
It also provides direct retrofit fast warm-up capability for the 7077/7486 family--about 3 seconds to 90% of steady-state plate current.
The new triode is another example of how GE product improvements can aid you in designing reliable, top performing equipment. Circle Number 235 for more information.

A TECHNICAL DIGEST FOR INNOVATORS OF ELECTRONIC EQUIPMENT

High performance d-c motors for computer and peripheral jobs

Don't miss this one-- Check these

smallest 50 mW, 2-amp Darlington amplifiers

relay on the market

for high gain

Nickel-cadmium batteries are reckargeable--last hundreds of times longer

New catalog has full information on GE panel instruments

New Hyper-Servo* d-c motors meet needs of single-capstan tape transports, disc packs, highspeed printers, card sorters and similar equipment.
Hyper-Servo motors offer instant response--to one millisecone up to 50 times more frequency response (band width)
*Trademark of General Electric Co.

It just taKes 50 milliwatts to operate this extra small, 2-pole, 2-amp relay.
Size-wise, this newest GE 150-grid relay is only 0.32" high, 0.31" wide, 0.61" long. And, it meets or exceeds MIL SPEC environmental, electrical req uirements.
Micro-electronic circuit

GE D16P monolithic Darlington amplifiers (D16P1, 2, 2N5305-8) with current gains as high as 70,000 are available in 2 housings. They offer dissipation capability of 400 mW or (with heatsink package) 900 mW.
D16P's high gain is ideal for preamplifier input stages requiring input

Get lasting battery power and versatility suitable for many commercial and consumer applications. Types include sealed, pressure-relieved, and vented cells. Custom designs to your specifications are also available.
Nominal ratings range from 0.1 amp-hours to 4.0 amp-hours in sealed

What's your special requirement for panel instruments? Taut band suspension, special scales or colors, one percent accuracy?
Check General Electric --we're now offering the biggest selection of sizes, ratings, and models ever!
The new GE catalog, GEC-1 076, gives you

D28C dB.

Model 5131.G32H (3.4" dia, 4.28" long)

Actual size

016P

than standard d-c indus- applications are ideal for

trial motors.

this rillay because of its

Fast, repeatable ac- low ojoerate power and

celeration is easy with: compatible size.

low rotor inertia, arma-

Like all GE 150-grid

ture circuit inductance, relays jthis 50 mW version

resistance; high torque - is available with options.

to-inertia ratio, constant You clan choose coil rat-

torque-per-ampere rela- ings for a wide range of

tionship, voltage con- system voltages, plus

stant. Circle Number 236. popular mounting forms

and heacer types.

Model 5BLG32HAl

Want n-ore facts? Circle

Rated Armature Voltage

12 volts

Number 237.

Current

8 amps

Rated Torque

32 oz-in.

Rated Speed

2700 rpm

Rated Output

64 watts

Shunt Field

PM shunt

Arm. Circuit

Inductance

82 µH

Resistance

.43 ohms

V Constant

.0291 V Sec/Rad

Torque Constant 4.0 oz-in./amp

Arm. Inertia

.0028 oz-in. Sec,

50 Milliseconds

Pulse Torque

320 oz-in.

Pulse Current

80 amps

Time Constant

Inertial

9.0 ms

Inductive

.19 ms

Torque/Inertia

(a) Rated V 40,000 Rad/ Sec,

Continuous RMS

Current Rating

8 amps

impedances of several megohms.
GE's D28C monolithic power Darlington also offers very high gain (60,000 typical at 200 mA) with higher power and current ratings. Dissipation is 1.2W in free air and 4.0W at 70C case. Continuous IC is 500 mA.
The high gain affords virtually unlimited applications including: power transistor drivers, touch switches, oscillators, amplifiers and buffers, plus audio output stages for TV, radio, and other audio equipment. Circle Number 238.

cells and up to 160 amp - prices, technical and or-

hours in vented types dering information on

at the one-hour rate.

the full line of General

GE nickel-cadmium Electric panel meters,

cells feature unique con- meter relays, controlling

struction providing avery pyrometers and other re-

high discharge rate ca- lated components. It also

pability. To find out more, describes a sales and

Circle Number 239.

service army that backs

up all your SPECIAL re-

quirements. To order your

free copy, Circle Number

240.

FOR THE NEW IDEAS IN ELECTRONICS, look to General Electric-- your best single source for electronic components
ELECTRONIC COMPONENTS SALES OPERATION

GENERAL

ELECTRIC 285-38

This page could hold 6,914,128,443.75 round dots one micron in diameter

ENLARGED 76,200 TIMES

.00003937"

We etch metal to micron tolerances every day

Ultra-precise photomechanical reproduction of metal and glass parts is our business. We're very good at it. We've been precision etching on aquantity production basis since we made fire control reticles and other parts for the military in World War Il. Now, with equipment like our new BMAPS computer-plotter system, we do it better and faster.
We picture amicron dot because we do work regularly to tolerances of microns, or even millionths of inches. As an example, with BuckbeeMears electroforming we produce standard stock sieves down to 5 micron hole sizes, guaranteed accurate within ±-2 microns. These are shelf
items, quantity produced. On hand-picked spe-

cials we can do better. If you need a little less precision--for fewer
dollars, of course--check our prices and delivery times for more routine etched metal or glass parts. We can make virtually any part that can be drawn on paper. Our prices are fair, and we think 10 days is long delivery.
Ask us about your requirements. We look upon ourselves as professional problem solvers. We have an impressive list of companies we have helped, and we'd like to add your name to the list. Call or write us today. The first man to talk to is Bill Amundson, our industrial sales manager.

E3 TJ l< E3 EE-ME

S CO.

152

Circle 152 on reader service card

245 E. 6th St., St. Paul, Minnesota 55101 /(612) 227-6371 The world leader in precision photomechanical reproduction
Electronics IApril 15, 1968

New Tally HR 150 perforated tape readers run for reliability. With zero preventive maintenance, the reader is designed for aminimum life of 10,000 hours. Intypical reader applications, minor failures would be experienced less than once ayear. Day after day, month in, month out, these new readers will give you "full bore" performance without costly downtime.
These remarkable "state of the art" readers operate asynelr:onously

and bidirectionally at 150 -- characters per second and feature a compact. self-contained design, low noise level and essentially zero preventative maintenance. Heart of the new reader is anew stepping motor technique which permits true pulse by pulse operation and avoids the wear and tear caused by continuously moving parts.
Tape loading is easy and fast. Reeling tension arms can be locked upright for convenient tape threading. Rewind is bidirectional at 40

inches per second. For full price,
delivery, and technical information, please write Torn Tracy, Tally Corporation, 1310 Mercer Street. Seattle, Washington 98109. Phone: (206) MA 4-0760. In Europe and the U.K., address Tally, Ltd., 6a George Street, Croydon, Surrey, England. Phone: MUN 6838.
Circle 153 on reade7 service. card

LI\R
PRODUCTION INTERFEROMETRY

...a new approach to linear
measurement provides
high-precision production floor inspection with
speed and economy

4111111·111111
inggingi

New compact optics puts interferometer in 31 /2 -in, diameter tube, revolutionizes absolute long-length measurement on production work. Model 121, in a 16 in. long tube, is double-path interferometer with self-contained laser and power supply, designed for N/C machine tool calibration. Model 127, in 8-in, long tube, is single-path interferometer, operates with external single-mode helium-neon laser, designed for measuring machines or permanent installatien on machine tools, for two-axis monitoring with single laser.
New portability--all components small enough to fit into an overnight case.
New high-speed counters designed and built by DoALL with microminiature integrated circuits. Bidirectional counters handle counting speeds to 10 Megahertz, ideally suited for fast target travel such as N/C machine rapid traverse. High-counting capability eliminates effect of shock or vibration.
New modulai flexibility--extra modules extend the capability to suit job requirements. A plug-in computer conversion board changes the visual nixie tube display from ambient fringe count to direct readout in inches or centimeters. Also, modules are available to compensate for temperature and pressure variations in the operating environment.
New distance capability--the helium-neon laser handles measurements up to 100 ft. w.thout repositioning.
New practical price--less than other instruments presently available to do the same work.
Find out for yourself what this new long-distance measurement system can do to cut the cost of quality control on production work. Call the nearest DoALL store. Ask for ademonstration in your plant on your work.

GB67-2R

154

Circle 154 on reader service card

DoALL Company, Des Plaines, Ill. U.S.A., 60016 (in greater Chicago area)
Go with DV L... the Productivity People
Electronics lApril 15, 1958

·Ale

zx

eleter · ·

s'isttexs

atIVOZ

. -

ect coeitetts atà %streeet.sreeîd tor ire) systens can be tee- s-

consum\ng· bus\ness.

`Jou afe

\OP doÀt-loutse se`ber`

Ge1ctPtoe:rmnegpertehneeenrtse\ervneee\et\enneroctosmtpaonndCeaanrndtsrPeyeWoçnuee`t,IeeurecotMbp\os·nents. eVaerç\atbo\deeainsdtprroesct\s\on

attenuates, waverneters, etted \\nes, ease steers, tern\nat\ons, antennas --

whatever your system reeres \r` the 12.4 to 220G\e`irang,e,IftG, can supp\y \t.

\ble efe e\se un\c\ueW nueed dese sPec\e\ ceeeets, esseeee

11:G Sees

Precien

systems to your spec\i\cabons. for west cho\ce -- and uncornpren\s\ng

Deect Fteaffinf. Attenuate, a

·

t

eoet

cateog to 1\le

ow\en, cormo` °e-a ce.e-`cell 4°4 de rcboaota:aIvnlrerdyesavyottaepnnineoejaiptrtreei>e`eeg*.sl,aae,tev,etee-efnWnneu.upo1iae%etdaeetet?,,acCerC , q muaestsiaclusetts 0212s. leeseone 617 ..569.2.110.

I

daeSi.tseeiSilencaird

Circ le 1S:l3eleitree

Tektronix 50-MHz dual-beam oscilloscope

The Tektronix Type 556 Dual-Beam Oscilloscope features
50-MHz bandwidth, calibrated sweep delay, 6x10 cm scan per beam and dual plug-in flexibility. Using two plug-ins at a time, the Type 556 offers many display combinations, including: dual-beam single-shot; multiple-trace; sampling and real-time; frequency and time; delaying and delayed sweep.

The two independent horizontal deflection systems provide full bandwidth triggering and calibrated sweep speeds from 5 s/cm to 100 ns/cm, extending to 10 ns/cm with the X10 magnifier. The calibrated sweep delay range is from 100 ns to 50 seconds.

The Type 556 with the Type 1A4 Four-Channel Plug-in and the Type.1A2 Dual-Channel Plug-in provides up to six chan-
nels, each with 7-ns risetime and DC-to-50 MHz bandwidth. (Up to eight traces with two Type 1A4 Plug-ins.) You can also
select from differential plug-ins with bandwidths to 50 MHz, TDR and sampling plug-ins with 90-ps risetime, and spectrum analyzer plug-ins that cover the spectrum from 50 Hz to 10.5 GHz.

For a demonstration, contact your nearby Tektronix field engineer or write: Tektronix, Inc., P. O. Box 500, Beaverton, Oregon 97005.

Type 556 Dual-Beam Oscilloscope TTyyppee 11AA24 FDouuarl--TCrhaacnenePlluPgl-uign-in
Type 205-2 Scope-Mobile Cart
U.S. Sales Prices FOB Beaverton, Oregon

$$$3372845000 $ 135

Multi-trace, differential, sampling and spectrum analysis

156

Circle 156 on reader service card

Multi-Trace
The six waveforms are time related digital pulses. The upper four displays are A Sweep (2 Ms/cm) with the Type 1A4 Four-Channel Plug-in. The lower two displays are B Sweep Delayed (100 ns cm) with the Type 1A2 DualTrace Plug-in.
Sampling and Real-Time
The upper beam shows asquare wave at 2 ps 'cm as applied to a Type 1A2 Dual-Trace Plug-in. The lower beam shows the risetime of the same pulse with the Type 1S1 Sampling Plug-in at 1 ns, cm.
Frequency and Time
The upper beam shows the spectral output of a 200 MHz gated oscillator applied to the Type 1L20 Spectrum Analyzer; calibrated dispersion is 1 MHz/cm. The lower beam shows arealtime display of the 2.5 ps gating pulse.
... in all Tektronix 530-540-550-series plug-in oscilloscopes
Electronics ;April 15, 1968

Probing the News

Systems engineering
Electronic traffic control: can it make the grade?

Most engineers are optimistic, but unreliable hardware and high costs are creating many problems for the cities

By Howard VVolff
New York bureau manager

Inside every traffic engineer there's asystems designer screaming to get
out. His frustration comes from looking at the infuriating tableaux that have become commonplace in American cities:
·A line of autos waits at acor-
ner for the light to change even though nothing is moving through
the intersection from the other direction.
·A string of signals along a broad, one-way avenue is set to keep things moving at 25 mph during the 5o'clock crush when actual speed is 5mph.
·Cars are backed up diffidently on afreeway entrance ramp as traffic on the freeway itself swooshes by at 60 mph.
Everyone agrees that there must be abetter way. Virtually everyone agrees that electronic traffic con-
trol is the answer. But almost no two authorities agree on just what mix of available hardware--sensors, detectors, controllers, computers-- can do the job best.
Better mousetraps. The people who design the equipment and those who buy it tend to operate on different wavelengths. The electronics engineers, in the words of one disgusted civil servant, "are obsessed with state of the art, with super-sensitive devices that can't be repaired by anyone who didn't go to mrr, and with the notion that
money is no object." Adds another:

Eye of the storm. Bill Gemell of the Long Beach, Calif., traffic department checks one of city's four eight-year-old computers.

"They seem to consider traffic control anice little market for stuff that
was designed to find out if there's life on Mars."
In fairness to the EE's, though, it's a rare traffic man who knows what's available and what he wants. One of those rare ones is Henry A. Barnes, New York's outspoken traffic commissioner. Not only does he know what's available and how it's

being used around the world, but he also likes to talk about it.
"What the elect:onics industry needs," says Barnes, "is a system permitting cities to use their present street-corner controllers. Such asystem should be modular, in increments of 100 intersections, to get the cost down to where smaller cities could afford the investment." And Barnes, still feisty after his un-

Electronics IApril 15, 1968

157

II. Keeping the motor running

Man in the street. Long Beach's Don Riedel, traffic signal foreman, works on Eagle signal controller on Pacific Coast Highway.

happy, and much-headlined, threeyear experience with the Sperry Rand Corp.'s Gyroscope division, is about to put his money where his mouth is: New York City plans to try out an International Business Machines Corp. system that incorporates controllers already installed on the city's corners.
I. Bumpy road
The Barnes-Sperry contretemps could yell serve as the first chapter of atextbook on how not to do business with amunicipal government. The $5.4 million contract, awarded in 1965 and canceled last January, was to be Sperry's entree into the traffic field; in fact, the company is believed to have underbid experienced competitors by more than $1 million because New York intended eventually. to spend $100 million on traffic control. The key to the situation appears to be changes made by Sperry in the original specifications, changes Barnes feared would leave the city open to lawsuits from the unsuccessful bidders. Not only that, but delivery of hardware was running more than two years late. "They just couldn't get the stuff to work," says Barnes. He also insists some equipment that was delivered was shoddily made. He says that on one controller shown to him by Sperry, he was able to loosen 23 screws with his thumbnail.
A considerable amount of hardware was called for. There were 1,052 detectors (which determine the presence of a vehicle); 1,397

sensors (which determine vehicle speed and direction); 2,693 controllers; 10 zone computers; and one central computer. It all would have been used to control 2,693 intersections, or less than 400 of the city's 6,000 miles of street. The sensors were to have been doppler-radar affairs mounted 17 feet above the pavement and operating in the Sband at 2,455 megahertz. But none was ever delivered; Barnes says Sperry couldn't get them to measure speed properly. All of the 58 controllers delivered failed. "The company then said it couldn't service them," adds Barnes. The computers were to have been digital Univac 413's; these machines are modifications of the 418.
Stuck in traffic. Sperry Gyroscope spokesmen refuse to talk. Barnes is more than willing. He says that Sperry considered the order peanuts when stacked beside giant Federal contracts, and tended to take engineers off the New York
job for reassignment to those more lucrative projects. Furthermore, Barnes maintains, the company's lack of experience in the traffic field stuck out like ared light and "top management" failed to exercise proper supervision. Even an 11th hour management shuffle failed to save the contract.
In the words of one man close to the situation, "What Barnes says is pretty much the way it was. It would be kind to say anice word
about Sperry's role, but it's difficult to think of one."

Meanwhile, um, one of the unsuccessful bidders for the New York
contract, kept working quietly on a traffic control system of its own. \Vhat has emerged is a picture of simplicity and economy: an off-theshelf model 1800 computer that interfaces with existing street-corner controllers.
Go west. IBM got its feet wet in San Jose, Calif., [Electronics, Nov. 14, 1966, p. 221]. The system was installed in 1965 using a model 1710 computer contributed by the company, but the city has since purchased a faster 1800 for $200,000. Induction-loop sensors are imbedded in the pavement, setting up
magnetic fields that are interrupted every time something metallic enters. Some of the loops are made by the Link group of the General Precision Systems Corp., some by RCA, and still others are homemade.
The computer, which can implement 128 timing patterns at each intersection, makes a total of six measurements.
Mecca. San Jose has become something of astar in the west for U.S. traffic men. They flock there to examine the traffic-control system in action and generally agree it's potentially one of the best around. Yet, many leave shaking their heads. The reason, in the words of one visitor: "Why don't they use the darned thing to control traffic? They kept showing me reams of statistics--numbers, numbers, numbers collected by the computer. They're so interested in proving that they saved the local drivers 1,500 seconds yesterday that they're ignoring the real reason the whole shebang exists."
The 1800 is so loaded down with engineering and statistical tasks that it's available for actual traffic control only a few hours a day. There appears to be disagreement within the traffic department on whether to control traffic or do research on traffic control.
In or over. The use in San Jose of buried loop detectors has contributed to an intrafraternity disagreement along the lines of buried vs. pole-mounted detectors. Backers of buried-loop devices say they're less likely to provide false measurements, are immune to weather, and are less expensive. The pole sitters

158

Electronics IApril 15, 1968

insist that such devices--ultrasonic or radar--are easier to install and maintain, don't interfere with buried cables and lines, and are capable of wider coverage. New York's Barnes points out that most of his streets have no foundations and therefore shift constantly, and that it's ridiculous to tie up traffic \Ail(' burying the loop inductors or digging them up later for repairs.
Still, the majority appears to favor the loop. The Philco-Ford
Corp.'s wm, division in Palo Alto Calif., is believed ready this summer to start selling a solid statu loop, using metal oxide silicon integrated circuits. It's now being
tested in Palo Alto and Oakland. Calif. However, Howard W. Carmack, assistant superintendent of Oakland's electrical department, feels that ic's are unnecessarily so-
phisticated for traffic controllers. Relays, he says, operate fast enough and aren't apt to go off half-cocked because of environmental noise.
The source. One can even get an argument that it's the computer,
not the sensors and detectors, that counts in electronic traffic control.
The man behind that argument. Oser I. Bermant of IBM, was also one of the men behind the San Jose
installation. His thesis is that problems arise
when analog computers are used. Such machines, he maintains, can't tell when asensor has gone wrong. Digital computers, on the other hand, can be programed to check each detector or sensor continu-
ously; when a failure is noted the computer can correct it or signal for repairs. "Digital computers have
changed the game," says Bermant. "They can offer flexibility, analysis.
and economy." While Bermant's view could Ix»
called part of his job, the rate at which 113M is convincing cities that
the digital route is the way to go lends extra weight. Wichita Falls, Texas, has 57 intersections under 1800 control; Portland, Ore., will link 85 intersections with an 1800
later this year; and Austin. Texas. will hook np 48 intersections, to be expanded to 200, with an 1800 in the fall. And, adds Bermant. IBM is going after "quite afew" additional contracts.
The other fork. Despite IBM'S success, many cities are skeptical about the efficacy of computers in
Electronics April 15, 1968

What the auto makers say
Car makers have not only thought about electronic vehicle controls, they have pioneered in them, in li::e with the industry philosophy that in order to remain competitive, it is necessary to have as much advance knowledge of market conditions as possible. In the case of science and technology, this means wading right in at the research stage.
General Motors. GM 's Research Laboratories have had programs on development of "automatic highways" since 1956. Included in cm's 1965 experimental Firebird III prototype car was an electronic steering system. Called Autoguide, the system included two pickup coils suspended beneath the forward end. They picked up signals from a cable imbedded in the road. The signals were ciphered by a small inboard computer and the car's steering system was automatically actuated to keep it on course.
Gm also has constructed and tested in miniature an automobile control system. Utilizing sunken highway cable, the system allows for ;automatic vehicle spacing, steering, and collision prevention--by slowing and, if necessary, stopping a car when it gets too close to one in front of it.
Gm had an extensive program with RCA in 1959, which culminated in the construction of an experimental automatic highway system at the acn. labs in Princeton, N.J.
Last July, General Motors Research Laboratories received a $493,000
Follow me. Experimental Route Guidance System provides head -up display mounted on dashboard to give directions.
Federal contract to develop hardware for and evaluate a kghway route guidance system. The contract called for:
· Experiments and instrumentation needed for an objective evaluation of route guidance.
· Practical hardware to investigate the feasibility and cost of anational routing system.
In line with the contract, cm has submitted plans for the hardware, supposed to be ready this June. The guidance system will work this way:
At the start of a trip, the driver dials his destination code into route guidance equipment inside the car. The vehicle automatically transmits the code to roadside equipment at key points enroute. After processing the code, the roadside equipment signals the driver by visual display or electronic voice inside the car, and gives him proper routing instructions.
Ford. A recently established Department of Transportation Research and Planning at the company will study all phases of vehicular activity ;is it relates to the over-all environment.
Foster Weldon, who heads the department, says Ford's programs are built around video readout computer simulation techniques using mathematical models of the various factors that make up urban areas-- physical, social, political, and economic.
A complete specification of the components--decision options--of a transportation system is fed into a series of computerized models that calculate transportation supply and demand relationships, interpret pricing, and predict effects of the system on growth and form of the region. Among the transportation systems under study is automatic vehicle control.--Vince Courtenay
159

... but the City of Angels gave up, went back to the old timeclocks

(with three new, forward-looking
unitized DVMs)
Trymetrics' new 4243 Digital Multimeter with AC, DC and OHM readings--auto
polarity -- full tour digit -- .01% ($850) ... atremendous step backwards. And so
are the 4240 DVM ($695) and 4230 DVM ($595).
We started with our Model 4100: stored display--precision .01%, four-digit DVM and its full range of plug-ins for the price of an ordinary 3-digit job--just $740 with
the --zl9.999v DC head; $1045 with acomplete multimeter head; and eight other plug-ins to choose from. For an encore, the only way to go was down.
Down $195 to $850 for the versatile 4243 Digital Multimeter: DC-AC-OHMS .01% -- auto polarity -±999.9mv to ±999.9v. Same 4-digit stored display--no plug-ins. Sorry--unless you don't need
plug-ins. Down again, $155, to $695, for the 4240
DVM. Same high accuracy, same stored display, same --t-999.9mv DC to ±-999.9v
DC 4-digit measurements. But, no AC or OHMS--unless, of course you don't need
AC or OHMS. Once more, down, to $595 for the
Trymetrics 4230 DVM. Still the same precise 4-digit unit with readings +9.999v DC to -±999.9v DC. Don't buy this one if you need to measure in the low millivolts.
You don't need true 4-digit readout with .01% accuracy at a 3-digit, .05% price? Sorry--but we can't keep backtracking forever. May we send you our new catalog that shows ALL our models, all our plug-in versatility, all our reasons for going backwards?

TRYMETRICS Corporation

204 Babylon Tpke.. Roosevelt, L.I., N.Y.

Phone 516-378- 2800

11575

160

Circle 160 on reader service card

general and digital equipment in
particular. One is Seattle. Robert Warr, senior traffic engineer for
signal systems there, says: "The electronics industry has offered a lot of fancy systems no one knows how to run. Computers have their place, but sometimes using acomputer to control traffic is like using ashotgun to kill afly."
All the same, Seattle is spending about $100,000 a year on control equipment, the biggest project being conversion of 150 intersections in the central business district. That five-year program will be completed this year, with Automatic Signal, adivision of Labora-
tory for Electronics Inc., the big supplier. Interestingly enough, Se-
attle's "shotgun" will be an analog machine.
Dallas Cooper, division superintendent of the Long Beach, Calif., Public Service department, has still another formula for success. "We've gotten pretty good results," he says, "because we've stayed with aproven system." That system includes four eight-year-old variablefrequency Eagle computers stuffed with vacuum tubes and loop detectors. There are four grids--the biggest involving 90 downtown signals--representing an investment of almost $500,000.
Land of Lincoln. Illinois is fund-
ing, designing, and installing systems on main expressways surrounding Chicago with 90% of the money coming from Washington.
The original test was on Chicago's Eisenhower Expressway in
April, 1961, and it was considered operational in November 1967
when Illinois installed control equipment on Chicago's Dan Ryan Expressway.
The system in Chicago is controlled by a General Electric PE/ PAC model 4040 process computer, amachine that was originally sold as a data logger.
Chicago's system uses loop sensors to count the traffic, converting the count into traffic density, and uses traffic densities to control signal lights that regulate traffic flowing clown entrance ramps into the expressway.

Comprehensive. Perhaps the most completely computerized traffic control is in Baltimore. The system, installed by Henry Barnes when he was traffic commissioner there, is now 10 years old and involves around 850 intersections-- some outside the city. Seven Automatic Signal tube-driven analog computers do the controlling, and avariety of detectors--radar, loop, pressure, and sonic--are on the job. Norbert Nitsch, assistant commissioner in charge of signal engineering, says the system works "exceptionally well." Evidence of this is the fact that the U. S. Bureau of Public Roads says the system moves traffic so well that an expressway isn't needed by the city.
Ill. Red light
In one large city, all signals for electronic traffic control aren't go. Los Angeles is unconvinced.
Los Angeles' attitude is particularly surprising in view of its almost total dependence on the automobile. But a28-signal system on Sunset Blvd. was switched back to timeclocks after two years, and the same thing was clone after twoyear trials on three principal eastwest arteries--Wilshire Blvd., Olympic Blvd., and Sixth St. Says William Hutchinson, assistant city traffic engineer: "Recordings of traffic patterns at peak hours on those streets indicated they were predictable to the extent that we could rely on timeclocics."
Los Angeles used a mw computer and peripheral sensing equipment. "The difficulty with the computer," says Hutchinson, "was that it would change the operational mode (signal patterns for the main artery as well as all cross streets) on the basis of what we would consider insufficient evidence. For example, during peak conditions the timing could be changed as often as every four or five minutes merely because adisproportionate amount of vehicles passed a particular point at aparticular time."
IV. The searchers
Past, as historians like to point out, is prologue; no one knows this

Electronics lApril 15, 1968

·

better than engineers--traffic and electronic. So even as they argue gently about sensors, computers, and timeclocks, they arc driving hard at test tracks and laboratories to make the future safer for mind and body of the Average American Motorist in his 400-horsepower Gaseater with the padded dashboard.
Detroit is the home of the National Proving Ground for Freeway Surveillance Control and Electronic Traffic Aids, which has tested various electronic traffic apparatus and systems since 1962.
The testing ground, asection of the John Lodge Freeway, is supported by the state of Michigan, Wayne County, city of Detroit, U.S. Bureau of Public Roads, and 13 other states.
Not here. In the 3.2-mile test stretch, traffic is directed by indicators above lanes that tell whether or not the lane should be used with either ared X or agreen arrow. In conjunction with the lane signals, there is an electric signal board that indicates vehicular speed requirements for optimum traffic flow and safety.
Input data is gathered by closed circuit television cameras and ultrasonic sensors mounted on 14 freeway overpass bridges. The cameras provide ramp-to-ramp surveillance, and feed into aconsole bank of receivers at Proving Ground headquarters. All cameras are General Electric TE9 systems that span 30° left and right, have full tilt arc, and telephoto lens. Cost, including installation, came to $10,000 per camera.
The sensors, made by the General Signal Co., bounce a pulse from the freeway. The return pulse is picked up and transmitted to a Control Data Corp. 8090 computer, which can assess vehicle count and speed with an accuracy of ±-20%.
Proving Ground engineers seek better detectors that will provide finer vehicle speed and count data. They suggest that doppler radar or light scan systems could be developed.
Reporting for this article was provided by Walter Barney and Peter Vogel in San Francisco, Bill Bell in Los Angeles, Ray Bloomberg in Seattle, Robin Carlson in Boston, Vince Courtenay in Detroit, Bruce Cross in Chicago, Barbara Koval in Pittsburgh, Bob Skole in Washington, and Mike Payne in London.
Electronics IApril 15, 1968

infqruiaanrrcethde:orf 50

Order your samples now of this newest General Electric solid state lamp.
This new action-triggering device is called the SSL-4. It's a gallium arsenide solid state infrared lamp. A bit less than aquarter inch long (excluding leads), you can fit it almost anywhere. Use it in card readers and photo-electric applications. Also in counting devices, machine controls, safety and inspection devices and tape readers.
SSL-4 will withstand severe shock and vibration far better than any filament lamp. And it can be operated at up to one million cycles per second. So it's sure to play an important part in future computer design. And a look at the diagram below shows how it'll work With Semiconductor Product Dept 's Photo-Darlington amplifier (L14B).
This is the third lamp in General Electric's growing SSL family. The others, SSL-1 and SSL-6, are 2-5 volt visible light sources operable to 10,000 cps. SSL-1, with a60° viewing angle, is aperfect photocell driver. SSL-6 has a 180° viewing angle, ideal for indicating jobs.
Order Your Samples Now! You can use all three SSL lamps to save space, improve performance and reduce maintenance costs in your product. Find out how. Enclose your check, money order or purchase order for $9.50 each with the coupon below. And do it now. Sample offer on all SSL's ends June 30.
For more information, send for free technical bulletins: #3-7384 (SSL-4), #3-8011 (SSL-1 and SSL-6).
Miniature Lamp Department

GENERAL

ELECTRIC

TO: General Electric Company Miniature Lamp Department
P.O. Box 2422, Nela Park, Cleveland, Ohio 44112

Attn: J. D. McMullin

Please send me Please send me Please send me

new GE SSL-4 lamp(s) at $9.50 each new GE SSL-1 lamp(s) at $9.50 each new GE SSL-6 lamp(s) at $9.50 each

Name Company

Addresq City

Suite

Zip
--J

Circle 161 on reader service card

161

Soon 010 landings (ceiling :0/horizontal visibility: 0) through use of the new I.L.S. auto-
matic landing system. Safety will now be
determined by the precision of I.L.S. equipment. In order to test unquestionably its perfection, we have designed the most exceptional generator (Phase 3). This infallible instrument is a must in guaranteeing the workability of your
I.L.S. system.

Immediately available: Type 310 -Phase 3-I.L.S. generator.

Amplitude balance 90/150 Hz

Accuracy :
Frequency 0.1 % Better than 0.02 dB (0,5 pA)
Usually -0.01 dB.

Stability: Frequency 5x10-" Balance 0,1 u.A
Performance : Constant sum attenuator (90 or 150 Hz)
0 to 20 dB continuously (scale to every 0,01 dB). -Continuous frequencies variation ±"3 %
Continuous variable phase From sinus to cosinus.

ARIOS ELECTRONIQUE 25, rue Ganneron -Paris 18. -France !V.H.F. -U.H.F. -V.O.R. -I.L.S. Generators Fifteen years experience of eervIce to aerial navigation. (Agents in great demand In every country)

Avionics
Simulators go to the head of the class

Airlines find electronic teachers cheaper, safer, and better than flight training, and will need more as new planes arrive

By Paul A. Dickson
Washington regional editor

During recent weeks, air carriers have been making what amount to
mass purchases of the airbuses to be built by the Lockheed Aircraft Corp. and the McDonnell Douglas Corp. Eastern, Trans World Airlines, Delta, Northeast, and Great Britain's Airholding Ltd. have all signed up for L1011's or DC-10's.
But Lockheed and McDonnell
Douglas aren't alone in their good fortune; producers of electronic simulators and visual aids also stand to benefit. For airlines are increasingly anxious to bring their flight-crew training down to earth.
For one thing, the skies are getting more crowded. For another, even more complex aircraft like the supersonic transport and the Boeing 747 are on the horizon. As a result, 'airlines are becoming more concerned about how to train their crews safely. Many now consider
electronic simulators with realistic visual displays the most practical
solution.
I. Safer, cheaper, and better
At a recent meeting of airline training officers in Washington, simulators versus in-flight training
was a hot topic. Officials from a dozen or so carriers agreed that safety was the main argument for simulators, but the machines have
lots of other advantages: ·Economy. The estimated cost
of an hour's training in a 747 is more than $2,000. An hour in a
simulator costs only a small fraction of this and doesn't result in loss of passenger revenues.
·Results. "We can let aman do and learn things on the ground that he could never try in the air," says one official. And Frank Petee, the training manager at Allegheny Airlines, says, "In the case of a

Stand-ins
While airlines are getting ready to buy computer-controlled simulators, a complementary airborne scheme is also attracting attention.
The so-called stand-in simulator is a smaller aircraft rigged up to act like a larger one. Cornell Aeronautical Laboratories Inc., working under an Air Force contract, is modifying aConvair C-131 to give it the flight characteristics of much larger planes like the giant C-5A or the supersonic transport.
In the Cornell program, dubbed TIFS for total in-flight simulator, an extra cockpit is installed in the front of the Convair for the trainees. The existing cockpit is manned by two "safety pilots" who will take control in an emergency. An airborne computer, programed with the characteristics of the larger aircraft, figures out how the smaller craft should act. Servos then drive flaps and other control surfaces to give the effect of the larger plane.
Cornell recently agreed to give commercial rights to the TIFS system to Aero Spacelines, a subsidiary of Unexcelled Inc. A spokesman for the company predicts sales of about 20 TiFs-type aircraft by 1972.

carrier like ours it isn't necessarily
cheaper to use asimulator, but we rule out this factor because we feel they do abetter job."
·Convenience. Flight crews can be ushered in and out of simu-
lators around the clock without the red tape of flight clearances and other airport procedures.
Airlines are willing to pick up
the first-class fares electronic firms
are asking for sophisticated training devices. Over-all, U. S. airlines now have 56 simulators representing an investment of $65 million to $70 million. Most of these machines have been installed in the
past five years. Before 1970, the carriers are expected to double their total investment by buying another 35 simulators. The new
units will cost an average of $2.5
million. General-aviation customers and overseas carriers will push the total market close to $100 mil-
lion. Value added. Furthermore, the

advanced simulators will channel more money into other electronic training aids. For example, Pan
American World Airways is thinking about using relatively simple
procedural trainers controlled by a computer. The system would be used to prepare crews for aBoeing
747 simulator. Although there are no projec-
tions for after 1970, ihere is every
reason to believe that the market will continue to expand. A spokesman for the Air Transport Associ-
ation sees two factors bolstering the upward trend: -The airlines are now becoming more and more dependent on simulators, and sales are tied to aircraft purchases,
which are rising." One manufacturer points out that
in 1960 airlines might have had only one simulator apiece but are now averaging one for every 15 to 20 aircraft. The number of simulators could rise to one for every 10
to 15 aircraft when the 747 goes

-E--Circle 162 on reader service card

163

NEW MAGNETIC RELAY plugs into your PC board!
NO Springs, NO Wiring, NO Sockets, NO Soldering,
NO Mechanical Linkage
PRlend® Standard Series G Latching Series LS/LD

(actual size)
Plated Conductors on Your PC Board are the Fixed Contacts
Save SPACE, MONEY and MANIIOURS with these new small, lightweight, highly reliable Standard and Latching PRINTACT Relays. Available with Bifurcated Palladium or Gold Alloy contacts for more than 10 million cycle 2to 40 pole switching. Handles up to 2amp. res. loads. Coils for 6, 12, 24 and 48 vdc at 500 mw. Operating temperature --30°C to +95°C. Operate time 7ms. The little gem is an 0.8 oz. 7/8" cube. Quality features include: double-break contacts; balanced armature, enclosed housing, plug-in application; encapsulated coil; self-wiping contacts and inherent snap-action -- saves sockets soldering, and wiring and the cost is lower than you think! *Switches up to 4form Aplus B, or 4 form C.
For data and prices write or call: 212-EX2-4800

PRINTACT RELAY DIVISION
47-37 Austell Place Long Island City, N.Y. 11101

164

Circle 164 on reader service card

ieb$1111,*1-14.
;1_rtnda
be

Truth in landing. The scale model of an airport runway looks like the real thing when viewed by TWA flight crews duplicating landings and
takeoffs in simulator. Carriers are pushing for even better displays.

into full service. United Air Lines'
experience at its flight training center in Denver typifies the carriers' new dependence on simulators. United, which now has 17 simulators, will receive another this month and has five on order: a Boeing 747 unit from the Link Group of the General Precision Equipment Corp. (with an option for another), two 747 simulators, a DC-8 machine, and a Boeing 727 unit from the Conductron Corp.

Within amonth United will select a visual system for the 747 machines from one of six competing firms. Herb Monroe, director of United's simulator division, says,
"The visual system may be used with two or three existing simulators like the 727 or DC-8 units."
Monroe notes that the Denver center has already made room for aConcorde ser simulator and that by the end of the year contract requirements will have been defined.

Electronics IApril 15, 1968

Overtime. The center is using its simulators from 6:00 a.m. to midnight; the wee hours are reserved for maintenance. A United pilot now gets about 80% of his training in simulators.
The story is much the same at Pan Am. The line now has eight simulators at three training sites and will soon add a747 simulator from Conductron to its facility at Kennedy International Airport in New York. Pan Am is now shopping for avisual system to supplement the 747 unit, and is considering adding visual aids to its older simulators. William Angleman, senior flight instructor, says the company is using its facility seven days aweek, with only afew hours out for maintenance. Similar conditions prevail at other airlines.
II. Sight unseen
Although the market for simulators is maturing, the airlines are also getting more demanding. They're seeking more realism in the simulator cockpit and in the sound systems. However, the consensus is that the most pressing need is for better visual systems.
The airlines want improved visual training aids and have banded together to present their demands. Under the aegis of the ATA, eight lines have set up acommittee and compiled a list of requirements for today's simulators and those to be developed for the SST and other advanced aircraft. Among the needs cited in areport issued earlier this year were visual representation of yaw and pitch and depiction of landing variables, such as engine reversing and braking. The committee would also like depiction of such operations as taxiing, docking, and circling.
The group requires a minimum field of view of 60° and has established specifications for resolution of the display.
Critics. The chairman of the ATA'S training committee, John A. Walker, aPan Am pilot, says: "Our
ultimate goal is to do all flight training in simulators." However, there are only six visual systems for the 56 simulators now owned by the airlines.
Walter A. Moran, director of flight training at American Airlines, says existing visual simulators are "quite limited in terms of replac-
Electronics IApril 15, 1968

VICTOREEN METAL OXIDE GLAZE RESISTORS
the perfect high voltage resistor?

you be the judge!

HIGH OHMIC VALUES 00 Kohms to 500 Megohms)

HIGH STABILITY
Less than 1% full-load drift in 2000 hours; shelf life drift less than D.1%/year)

HIGH PRECISION
(Tolerance of 1% and 2% all values; 0.5% in limited values)

HIGH VOLTAGE
(Voltages to 15 Kv with power ratings to 5watts 0/ 70°C)

Victoreen's new MOX Series is anew generation of metal oxide

glaze resistors. If they're not actually "perfect," at least they're ideal

-- for meter multipliers ... high-voltage dividers and bleeders...

high-voltage probes ... electrostatic paint spray equipment . .pulse

forming networks, etc. Why fight it? You can't beat a metal oxide

glaze resistor--now that you can get Victoreen MOX resistors

with values to 500 Megohms.

A-1110

VICTOREEN INSTRUMENT DIVISION
10101 WOODLAND AVENUE ·CLEVELAND, OHIO 44104
IN EUROPE: GROVE ROUSE, LONDON RD., ISLEINORTHL MIDDLESEX, ENGLAND

VICTOREEN

Circle 165 on reader service card

165

what's the winning combination?
Bell & Howell's matchless pair:
007 and 008
OPtima1 OP AMPs
(ACTUAL SIZE)

TYPE 20-007 general purpose Optimal op amp
TYPE 20-008 FET input Optimal op amp
They can't be matched in performance, size, and price. And paired, they make the winning combination for universal use. They are identical in package and lead configuration: check the specifications given below for performance and quality. Both have these internal features: voltage offset trim, frequency compensation, and input-output protection.
NOTE: Our quantity prices are based on the total number of units ordered, in any mix. Compared with other op amps of this size and high performance, the matchless pair is your best buy.

20-007 20-008

Price (in quantities of 100, any mix) $16.50

Voltage offset

200 ,,V

Input bias current 150 nA

Common mode rejection

100 db

Gain band width (at 10 kHz)

20,000,000

Output current

5 mA

$26 200 ,,V 10 pA
76 db
20,000,000 5 mA

COÍITROL PRODUCTS Division

CI BELL HOWELL
Write or telephone. 706 Bostwick Avenue, Bridgeport, Connecticut 06605. Telephone: (203) 368-6751. Ask for Mr. lsdale.

166

Circle 166 on reader service card

ing the real world."

Deficiencies of the visual simulators are, then, the real stumbling

block in making the simulator a

total trainer for the airlines. And

the problems are compounded by

the lines' refusal to underwrite re-

search and development in this

area. Says one airline official, "An

airline R&D program is called a purchase order."

Side order. About half a dozen

firms are making visual systems, usually sold independently of the

simulator. Systems cost from $250,000 to more than $800,000; the most expensive comes from the Dalto Electronics Corp. The com-

Tilt. New generation of simulators
like this one from Link have double the number of axes of motion freedom.

pany's equipment is currently the only visual system being ordered by an airline; TWA has contracted for amodel 4000 wide-angle visual flight simulator.
Dalto has supplied visual simu-
lation gear for such customers as Lockheed, NASA, the General Dynamics Corp., the Air Force, and the Navy. Robert Friedman, vice president and general manager, predicts amarket for 40 visual systems among five major airlines alone during the next two years. These would be for existing and new simulators. Friedman says he expects Eastern, American, and Pan Am to announce purchases of Dalto equipment soon.
With interest now centering on visual simulation, several types of systems are competing:
·Dalto's DEC 4000. A highresolution, closed-circuit, color television system whose camera follows the pilot's maneuvers as its scans a terrain model of a typical
airport and its surroundings. The camera has a single wide-angle

pilots in takeoffs and landings under limited visibility. The film is made in the course of flying an ideal pattern. 'Desired visibility conditions are added during processing. The system uses an anamorphic lens--one with greater magnification in one axis than in another--driven by aservo attached to the student's controls. If the student veers to the right of the proper landing path, the view of the runway appears as it would if he had made the error in flight. The Air Force will buy the first VANIP for use with an F4F simulator. Link offers the system as an option with its simulators for $265,000.
·Conductron has a wide-angle optical system with map models of
the ground or airport terrain made of photographic transparencies. The transparencies are spliced together in continuous belts approximately 12 feet wide by 52 feet long. Altitude changes are depicted by use of azoom lens.
Ill. Dynamic Duo

lens that picks up the image from the terrain model. The image is relayed into four identical window channels via abeam splitter in the camera. Each channel contains an image corresponding to the perspective that would be seen from
a cockpit. Four high-resolution orthicon cameras scan the images to provide afour-window display in the simulator cockpit. The system presents such variables as takeoff, approach, landing, taxiing, circling, and terminal parking.
·Link's variable anamorphic motion picture (vAmr) system. It uses 70-millimeter Todd-AO color
motion picture film for training

There are more than a score of firms in the simulator business. But the commercial airline aircraft sector is still dominated by Link, which supplied 36 of the 56 machines now in service. The runnerup, the Curtiss-Wright Corp., has provided nine analog systems. Of
the dozen simulators now on order by the airlines, about half will come from Link and the rest from Conductron.
Both companies are now using general-purpose rather than special-purpose computers in their
simulators because their assignments are getting so complex. In the 727 units, 120 discrete and 40

Electronics IApril 15, 1968

Precision engineered for airborne systems.

When you need precision --notors and gearmotors, call on Globe. Most experienced designers do. Globe motors are designed and engineered for demanding applications. And the selection is unusually b-oad.
We will help analyze your system problem and recommen the optimum motor/gear train combination,
Electronics IApril 15, 1968

and eN.en help you develop the next assembly (actuator, blower, pump, black box). Globe can suggest many methods to save power, space, weight in system design. Our specialty lies in
amboltyorusndaenrdaldlevMiIcLescotnhdaittiocpnes.rate re
Whatever your airborne motor system need, call on Globe.

For detailed information on Globe capabilit es and products, contact Globe Industries Division of TRW Inc. 2275 Stanley Avenue, Dayton, Ohio 45404. Phone (513) 222-3741.

Circle 167 cn reader service card

167

r.

· ."

"I ·

···

·

`I ·

0 R. T H AT I-AN Tic ·-Nc) R, Tim AT 1_,ANTIC

·TI_JANTIO" ·NORTH AT

·1\1. R, T

R, la AT

'T'

·NORT1-1 AT

·'I' I_,A -r·T

H ATLANTIC. NO T

0 R., ·T1_,
0 12, ·TIA

·1\1- R, TH AT L.,A. 1\7" rI" I TI_,ANTI C .·NOR, T
R.TH AT 1_, ANTI TIC ·NOR rf o

0 R.' · T

IT·I\T

1\1" rr I R,

· T

41\T T

·TI

I ·

' I · T

'T0L_,

I 4.

0 R..,

.1:1 I ID

·MLA..

O'·INTO

7' I

0 R. '1

R.TH AT LAN TI

· T

ATL,ANTIC. NOR, T

0

ANTIC ·NORTH AT 1_,AN T I ·

· T

NO T

A= L., A. iv IO" ·NORT

R.TH .AT

1\1-T I0' ·NORTH AT 1_, ANTI·

4T1_,ANTIO- ·NORTH ATLANTIC ·NORM

0 R. T H PT

NTIC ·-1\1-0 R. T H AT LAN T

·TL,A_NTIC ·N 411,

.41.

4

IL

·

IM

--

digital to

resolver/synchro

converters ... here's

the next generation!

North Atlantic now brings you a new generation of solid-state digital-to-analog converters. They offer major advances in resolver/synchro conversion accuracy along with drift-free and stable performance unobtainable with currently available resistor/amplifier devices.
Typical of these new instruments are the Model 536 D/R and Model 537 D/S "shoebox" converters (11-13 bit) and the Model 538 D/R-S converter (14-17 bit). Both models use solid-state switched trigonometric transformers and feature input data storage registers thereby saving computer time. Conversion speed exceeds 10 microseconds. Built-in overload and short circuit protection assures trouble-free system integration and reliable on-line performance.
Your North Atlantic representative (see EEM) has complete specifications and application information. He'll be glad to show you how these new converters can be the answer to critical interface problems.

AT

industries, inc.

TERMINAL DRIVE, PLAINVIEW, NEW YORK 11803 ·516 - 681 -8600

168

Circle 168 on reader service card

variable failures had to be programed; the 747 simulators will have about 1,000 programed malfunctions.
Link is using Scientific Data Systems Inc.'s Sigma 5 computer in the 747 simulators and Conductron is using Honeywell Inc.'s DDP-324 machine for its 747 orders. Thomas R. Bristow, assistant director of advanced trainers and simulators of Conductron's Missouri division, points out that the switch to a general-purpose computer allows a company to specify the best machines available and use manufacturer-supplied software. Software includes assembly programs and debugging routines as well as Fortran programs for updating the simulation program.
Link and Conductron are providing six axes in their 747 simulators double those of their 707 and DC-8 units. The gain will permit aircraft motion to be simulated with greater realism.
The greater complexity of the 747 and the SST will arise from more control surfaces, for example, as well as more radio and navigation aids. All this requires not only greater computer capacity but also more interfacing circuitry and subsystems.
Customer's men. Both Link and Conductron would like to massproduce simulators. But they find that it's impossible because of the equipment differences from airline to airline. Each carrier will wind up with a custom-designed unit. The same is true for visual attachments. Dalto's Friedman notes, "Everybody is asking for something entirely different, but that's the nature of this business and it will probably never change."
Monitor. The Federal Aviation Administration, which must qualify simulators to replace in-flight training, is all for the greater use of such systems. "We believe in them and encourage their maximum use," says Ralph Noltemeier, chief of the agency's flight technical program in the flight standards division. "Theoretically, it's possible to achieve a one-to-one transfer between the real world and the world of the simulator." But he points out that this depends on the development of motion cues in the simulator and on the visual attachments.
Electronics IApril 15, 1968

Electronics April 15, :968

Vote ITT for the largest, longest, promptest Teflon* insulated cable from Maine to California.
When you vote ITT, you're backing a machine that turns out Teflon insulated cable instead of political prose. Our new TFE extruder, largest in operation, makes longer lengths and larger gauges--up to 4/0--than any other. Of uniform quality, too. Lengths and sizes of TFE insulated cable that no one else can give you. In fact, the lengths are governed only by reel sizes.
ITT went to great lengths to get this machine. We think it's worth it because it helps us to provide uniform wire and cable in lengths and sizes that reduce your installation costs. Cast your vote where it counts.
Let us help solve your TFE insulated cable problems. ITT Wire and Cable Division, International Telephone and Telegraph Corporation, Clinton, Mass., 01510. In Europe: ITT Wire and Cable Division, Lister Road, Basingstoke, Hants, England.
*Dupont Trademark

ITT WIRE AND CABLE

Circle 169 on reader service card

169

WE'RE HANDING YOU A LINE...

ELEVEN NEW GUARDIANP. TUBULAR SOLENOIDS TO FIT EVERY APPLICATION From the tiny 7/16" diameter 13.5 to the jumbo 2" diameter T16, the Guardian tubular solenoid line answers every call for close-fit, easy-to-install, high performance solenoids. Clean design allows sideby-side mounting. Guardian tubular solenoids practically install themselves. Just insert threaded bushing through installation hole and tighten the furnished nut.
Available 6, 12, 24 and 115 VDC with pull-type operation ranging from 1 oz. to 30 lbs. capacity. Push-type also available. Life expectancy at rated load is 10' cycles minimum.
Drop a line for full specifications including pullstroke graphs. Ask for Catalog TS.

GUARDIAN

ELECTRIC

GUARDIAN ELECTRIC MANUFACTURING COMPANY 1550 W. Carroll Avenue, Chicago, Illinois 60607

Military electronics
Navy drafts standard hardware

Service is using uniform electronic modules for fire-control system of Poseidon missile to relieve maintenance and logistics problems

Military commanders in the field-- engineer at the Special Projects

beset by the logistics and mainte- Office. "All we want to specify is

nance problems involved in using what the module must do and how

electronic equipment of varying it fits into the system."

age, condition, and complexity--

In addition to keeping weapons

pray often for standardization. systems up to date technically, the

However, designers are apostles of principal advantage of the standard

change, anxious to usher in im- hardware program is ease of main-

provements as quickly as they clear the laboratory.
In an effort to reconcile the di-

tenance. In most cases defective modules will simply be replaced by plug-in units that are physically

vergent and parochial interests of identical.

both groups as efficiently as possi-

Complications. Feathering the

ble, the Navy's Special Projects Navy's nest is proving to be acom-

Office is going at flank speed on a standard hardware program (srip).

plex task for vendors. Notwithstanding the Special Project Office's

Number one. The Poseidon mis- boast about dealers' choice on cir-

sile will be the first major project cuitry, the rigid reliability require-

affected [Electronics, May 1, 1967, ments effectively dictate that ad-

p. 35]. Initially, the program which vanced solid state technology be

is designed to standardize modular

building blocks without sacrificing

flexibility in circuit design will zero

in on the missile's Mark 88 fire-con-

trol system. The General Electric Co.'s Ord-

nance department at Pittsfield,

Mass., is building the Mark 88 for

the 31 submarines that will carry

the Poseidon. The fire-control sys-

tem on each craft will have about

16,000 electronics modules, some

5,000 of which will be made to sill,

specifications. If all goes well, many

other Navy projects will eventually

adopt standard hardware.

applied. So far, most of the modules have been hybrid arrangements with both integrated circuits and discrete devices.
In developing the standard hardware program, the Navy has selected 136 electronic functions it considers widely applicable. Another 16 are under study and may well wind up in the Mark 88. An
estimated two-thirds of the selected functions could be applied in other
systems. An electronic function is Navy
jargon for a module's job assignment within the system. The possible variations are virtually limitless. Among other items in the Mark 88, there are: an isolation module with 19 direct-through connections; a15-

I. Means to an end

What the Navy hopes to have when the Mark 88 goes operational
in the early 1970's is a design so versatile that technological innovations can be incorporated at any point in the system's life. To achieve this, the physical and functional characteristics of the modules are standardized. However, the circuitry can evolve right along with technological developments. "I don't care whether vendors stuff a vacuum tube or alarge-scale array
inside, so long as the package does what it's supposed to," says astaff

The long and the short of it. Poseidon missile at right is slated to replace the Polaris in 31 of the Navy's submarines. System will have Mark 88 fire-control gear incorporating 5,000 standard hardware modules.

-+-Circle 170 on reader service card

171

A- to -D Converters
... up to 12 bits
...loaded with options

... big orders should lure more bids from industry.
volt capacitor module; and atransformer module.

41 /2 "x29A6" xY4"
·High-frequency FET input amplifier.
·Bipolar or unipolar input signals of varying ranges.
·Parallel and serial outputs of binary or BCD codes.
·TTL logic for high speed and fanout drive capability.
·Resolution up to one part in 4096 (12 bits)
·Extended temperature capability.
Get any of these options easily in the Pastoriza Model ADC-121c analog-to-digital converter -- without the usual delays and extra cost that "specials" always involve.
The 12-bit Model ADC-12,, is a single-card, general purpose, integrated circuit A-to-D converter that accepts input voltages on command and converts them to a 12-digit binary code in 25 microseconds. The single card contains an input amplifier, precision reference supply, logic, weighing network, switching, comparison, and internal clock. Only external DC power is needed.
The Model ADC-12,c 12-bit converter is just one of Pastoriza's many competitively priced A-to-D and D-to-A converters. All are available with avariety of different input options, resolutions, and output codes.
Write or call for more information on ADC TTL Series.
PASTORIZA
ELECTRONICS, INC. 385 Elliot St., Newton, Mass. 02164 · 617-332-2131

IL Second sources Because of the volume lots in-
volved, an ancillary advantage of standard hardware is that the Navy gets bids on modules from more vendors than usual. At the moment, 19 firms that are across-section of the electronic industry are qualified to build modules for the Mark 88. Thus, the isolation module that was developed by the Control Data Corp., Minneapolis, Minn., is also supplied by CE. Similarly, a diode unit developed by CE is also turned out by Globe-Union Inc., Milwaukee, Wisc., and Texas Instruments Incorporated, Dallas, Texas.
To become qualified to participate in the program, a company must first bid for aparticular contract. Under such agreements, the firm is given afree hand on internal design. Reliability, performance, and packaging specifications are the only constraints.
Suppliers do a lot of reliability testing, including burn-in, on their own. After production, anumber of units are picked at random for shipment to the Naval Ammunition Depot in Crane, Ind. Here, they are subjected to exhaustive environmental checks. Suppliers whose output passes these tests automatically become qualified bidders. However, should a spot check reveal deficiencies at any time, ven-
EXTRACTIOU FIfl
-- KEYING PIN
-- MODULE CONTACT PIN
Starting point. The basic module in the Navy's standard hardware program measures 2.62 by 1.95 by .29 inches.

HOW SYNCHRON'MOTORS
control this specialized
TIME-DELAY RELAY
In this special design timer aHansen SYNCHRON Motor drives the camtype sequence timer for an electronic time-delay relay. When power is applied, SYNCHRON runs through the first three sequences; starts the timedelay relay, then stops. Relay performs a panel-adjustable delay period of 180-240 seconds, then returns power to the motor to complete the sequence. Special applications are easy to design, using SYNCHRON Motors. How about yours? Call or write Hansen, or your SYNCHRON representative, for brochure and all the facts.
SYNCHRON timing and control motors; 168 different speeds. Right, left or reversible rotations. 8, 20 or 30 oz.-in. torques; 220, 110 or 24 volts; 60, 50 or 25 cycles.
Visit Booth No.1919, Design Engineering Show.
RI HANSEN
Manufacturing Co., Inc.,Princeton,Ind.47570
HANSEN REPRESENTATIVES: CAREY & ASSOCIATES, Houston and Dallas, Texas; R. S. HOPKINS CO., Sherman Oaks, Calif.; MELCHIOR ASSOCIATES, INC., San Carlos, Calif.; THE FROMM CO., Elmwood Park, III.; JOHN ORR ASSOCIATES, Grand Rapids, Mich.; H. C. JOHNSON AGENCY, INC., Rochester, N.Y.; WINSLOW ELECTRIC CO., Essex, Conn., Narberth, Po., and New York, N.Y. EXPORT DEPARTMENT: 64-14 Woodside Ave., Woodside, N.Y.

172

Circle 172 on reader service card

Circle 50 on reader service card

dors are knocked off the list. Getting back on involves repeating the original routine.
Double standard. In an effort to cut paperwork, the Navy decided to set only two environmental standards for modules. Class 1covers temperatures from 0° to 60° C; in Class 2, the range is from --40° to 100° C. Modules are judged on their capacity to stand up under varying conditions of temperature, humidity, shock and vibration. For example, modules in both classes must be able to withstand ahigh degree of relative humidity at 44° C for 96 hours. Likewise, units must be able to take one-half sine pulse of shock for 11 milliseconds at 50 G's.
The Navy expects that competition will reduce the price of modules. So far, however, this has not been so. One standard logic module, for example, is now going for $50 a shot. Officials hope an "acceptable" level will be reached this year when bids for the production contract are received. While they're not talking about what they consider acceptable--for fear of influencing prospective bidders--a $5 price tag would appear to be in the ball park.
Commenting on the standard hardware program, an industry spokesman says: "Most companies will go for the concept but not without some reservations and nervousness. The idea is still new to them, and while it sounds good, there's a lot of skepticism." This source notes that electronic outfits realize that maintenance and logistics as well as responsiveness to changes in the state of the art are increasingly crucial concerns of the military services. He speculates that with the Pentagon enforcing functional modularity, it will eventually prove advantageous to apply such techniques in commercial hardware.
But not everyone views the standard hardware program as amillenium. "It sounds rather like the Navy's trying to make the industry into ajob shop," says asource at a subcontractor on the Poseidon program.
Eventually, the Navy should be able to reach its low-cost goals because--in theory at least--vendors turning out standard hardware should be able to keep their lines open for longer runs. This factor
Electronics lApril 15, 1968

smaller-than-ever power modules!

Of particular interest for up-to-the-minute computer and systems applications, Technipower's 1968 lines feature modules up to one half the size of standard competitive equivalents, as a result of unique design concepts. Three new series of ultra-compact, highly efficient modules are available now!
PL-80 Series -- Regulated AC-DC Supplies
3.0 to 152 VDC, to 75 watts -- Temperature rating 80*C 432 models, featuring 0.05% line and load regulation, 0.002% ripple, up to 20% output adjustment range. Designed to meet MIL environmental specifications.
HF-80 Series -- Regulated AC-DC Supplies
2.8 to 1000 VDC, to 375 watts -- Temperature rating 80°C 75 models (including models capable of 5 volts (n) 50 amperes output), regulation, by high frequency transformation methods, -±(0.05% ± 5 mv) line, ±(0.10% + 10 mv) load, 2:1 output adjustment range, series operation permissible. Incorporated EMI suppression components designed to meet MIL-I-6181D.
CD-95 Ser es -- Regulated DC-DC Converters
2.8 to 1000 VDC, to 250 watts -- Temperature rating 95°C 84 true converter models, full isolation between input and output for local regulated DC power. Regulation -_L-(0.05% ± 5 mv) line, -±(0.10% ± 10 mv) load, ripple 0.2% ± 10 mv 2:1 output adjustment range, series operation pennissible. Incorporated EMI suppression components designed to meet MIL-I-6181D. Fully encapsulated, meets MIL environmental requirements.
Write for fully descriptive literature, which includes nstallation
data and prices.
TECHÍTIPOWER

A BEr1R-IS SJIDsidiary Benrus Center, Ridgefield, Connecticut 06877 Phone: (203) 438-0333 TWX: 7'0-450-3631
Circle 173 on reader service card

173

Evaluate these new Babcock Relays in your system. You'll find them "ON THE SHELF" at these distributors!
AVNET ELECTRONICS CORPORATION 10916 Washington Boulevard Culver City, California Phone: (213) 8704111, (213) 8704141 TLX 674-354 344 Middlefield Road Mountain View, California 94041 Phone: (415) 961.7700; TLX 34-8441 First National Bank Building. East 5301 Central Avenue Ni., Suite 1400E Albuquerque, New Mexico 87108 Phone: (505) 265-7926; TLX 74-6459 2318 6th Avenue Seattle, Washington 98121 Phone: (206) 623-8824; TLX 32-249 1729 North 28th Avenue Phoenix, Arizona 85009 Phone: (602) 272-6921; TLX 66-750 1020 W. Ellsworth Avenue Denver, Colorado 80223 Phone: (303) 623-6255; TLX 45487 207 Cambridge Street Burlington, Massachusetts 02103 Phone: (617) 272-3060 3901 Pace Court Schiller Park. Illinois 60176 Phone: (312) 678-6310: TWO 312-678-2522 70 State Street Westbury. L.I., New York 11590 Phone: (5(6) 333-8650: TLX 12-5928 4940 Viking Drive, Suite 208 Minneapolis, Minnesota 55435 Phone: (612) 920-5866; TWO 910-576.2784, TLX 029-5250 87 Wingold Avenue Toronto 19, Ontario, Canada Phone: (416) 789-1838; TLX 02-29195 1505 Louvain Street West Montreal II, Quebec. Canada Phone: (514) 0381-9127; TLX 01.20678 P. 0. 0. ELECTRONICS CORPORATION 9559 lrondale Avenue Chatsworth. California 91311 Phone: (213) 882-0500; TWO 910-494-1235 POWELL ELECTRONICS, INC. S. Island Road, P. O. Box 18765 Philadelphia, Pennsylvania 19101 Phone: (215) 724-1900; TWX 710-6704465 10728 Hanna Street Beltsville, Maryland 20705 Phone: (301) 474-1030; TWO 710-828-9710 P. 0. Box 488 Fayetteville. Tennessee 37334 Phone: (615) 4334737; TWO 810-380-3890 2049 W. Central Boulevard Orlando, Florida 32805 Phone: (305) 42343586; TWO 810-850-0155
Foreign Representation:
SWEDISH ELEKTROLINK AB Stora Nygatan 39 Stockholm C. Sweden Phone 114595; Cable Telelink A.E.M.C.P. 115 Avenue 1. B. Clement Boulogne srSeine, France Phone 825.96-20: Telex 842.27985 BODATAER CATON 8022 Grunwald Ber Munchen Iteltenstr. 2a, West Germany Phone 471862
For price, delivery and application data call Babcock collect. Be sure to ask for Ext. 1000 when placing your call.
BABCOCK RELAYS

... the Navy wants to increase the number of throwaway modules. .

should reduce outlays for tooling, training, and related items. However, much will depend on just how
many big programs are brought under the standard umbrella as well as on how much interchange proves practicable.
New home. Engineers at the Special Projects Office are optimistic
about expanding the number of applications for standard hardware.
And they are specifying that modules be used in several of the Poseidon's automatic fault-finding equipment and test sets to reduce the
logistics base still further.

Officials in charge of two other big Navy programs plan to incorporate standard hardware modules. These programs are the Walleye air-to-ground missile system and the AN/mg-13 Sonar. Other designers, particularly those working on avionics and astronautics projects, are considered likely converts.
Ill. Missionary work
Navy engineers are confident other systems designers will be enlisted, citing these attractive advantages of standard hardware:
·Because of Navy assistance and

"11me

····MMe

Third-generation fire control
The Mark 88 fire-control system has many complex assignments. It keeps the 16 Poseidon missiles carried by the submarine ready for launch, and stands by to feed in up-to-the-minute target data. Complicating the system's mission is the fact that each missile has a number--probably eight --of independently targetable nuclear warheads with total firepower equivalent to 20 million tons of TNT for lift off to treas as far as 5,000 miles away. In addition, the system must be failsafe and so encoded that it can be actuated only on the direct orders of the President. Finally, the Mark 88 must operate reliably in the hostile environment of the oceans' depths.
The Poseidon's Mark 88 fire-control system is being built by the General Electric Co.'s Ordnance department under a subcontract from the Lockheed Missile and Space Co., the prime contractor.
Number three. The Mark 88 is a third-generation fleet ballistic missile fire-control system. General Electric also built the Mark 80 for the early Polaris subs. The design of this equipment was an analog/digital arrangement and the gear was used in only 10 subs. The Mark 84, also made by CE, came next. It is basically adigital system.
The Mark 88, now in advanced design phase, will first be installed on the USS James Madison in 1969. Then 30 more of the subs now carrying the Polaris will be equipped with the Poseidon and will have Mark 88's installed (hiring regular shipyard visits.
The entire Poseidon program is costing the Navy more than $2 billion. In addition to the improved missile and the Mark 88, the system will carry new navigation gear.
In addition to its primary duties, the Mark 88 will compute missile motion at the time of launching, translate all data inputs to the missile, align the guidance system in azimuth, and set the missile's guidance timing.
Versatile. The multiple-targeting capability is the main operating distinction between the Mark 84 and the Mark 88. This capacity requires higher speed and accuracy in the digital geoballistic computer for targeting and target flexibility. This is provided by the rapid insertion of new target data and assignments into the guidance computer.
A fully automatic control system will prepare the missile for launching. The firing console will contain logic circuits that will initiate each launch step in sequence after the "Go Code" is fed in.
The entire firing sequence can be activated by pushing abutton. During the firing sequence the control system will automatically check each missile's readiness. If amissile is faulty, it will be bypassed and the sequence continued. The operator can intervene manually at any point in the automatic sequence.

174

Circle 174 on reader service card

Circle 175 on reader service card-->-

Four New Babcock Relays

BR42
·Welded Crystal Can ·2Amp.--DPDT ·Single-Coil ·Universal Contacts ·To MIL-R-5757

BR30
·One-Inch Ci.be ·t· PDT-1C Amp. ·Single-Coi ·All-Welded ·To MIL-R-6106

BR24
·Welded, Low Profile 10 Amp.--DPDT
·Single Coil ·Universal Contacts
To MIL-R-5757

BR26
·We dedHalf-Size ·2Amp.--DIDDT
·Single-Coil ·Uriversal Contacts ·To MIL-R-5757

BABCOCK RELAYS
Babcock Electronics Corp. 3501 Harbor Blvd. Costa Mesa, Calif. 92626 Telephore: (714) 540-1234

New: £t significantly lower prices! Still the same: Babcock qualit
Where: At your Babcock distributor When: _\

Need thirty different photocells? Or thousands exactly alike?

In either case, specify "Raytheon." Raytheon now offers standard and special types with cadmium sulfide or selenide sensors, TO-5 case or glass vial packaging, and a wide range of operating characteristics. These photocells are interchangeable with competitive types, available to MIL specifications, priced from 90e to $1.60 in production quantities.
All Raytheon photocells feature: rugged mechanical construction, small size, light weight. Low noise, completely ohmic light-dependent vari-

able resistors, their characteristics and high voltage capabilities ensure fast switching, temperature stability and linear response to illumination.
Wide range of characteristics. Our CK1201, for example, features 150 ohms resistance at 100 ft. candles, rise-fall time of 3 and 60 ms, 75 mw power dissipation (maximum). And our CK1266 features 2500 ohms resistance at 100 ft. candles, risefall time of 1.5 and .6 seconds, and power dissipation of 100 mw maximum.

Send reader service card for data on the complete line of standard Raytheon photocells. Or tell us about your special requirements. Raytheon Company, Components Division, Quincy, Mass. 02169.

RAYTHEON

Industrial Components Operation -- A single source for Circuit Modules/Control Knobs/Display Oevices/Filters/Hybrid Thick-Film Circuits/Industrial Tubes/Optoelectronic Devices/Panel Hardware

176

Circle 176 on reader service card

the single-minded nature of the
modules, development costs are relatively low.
·Design and test documentation are uniform; mechanical and electrical interfaces are standard.
·Potentially, there are broad applications for most modules.
Throwaways. Navy engineers are preoccupied with upping the number of modules that can be jettisoned rather than repaired when they fail. To this end, the Special Projects Office worked closely with the Naval Avionics Facility in Indianapolis, Ind., to determine which electronic functions lent themselves to broad applications--and hence standardization.
Only modules that can be specified by function are taken into the standard hardware program. Units thus chosen are generally considered nonrepairable. In cases where a custom module is required, it is thrown into adesign-disclosed category. When this happens, the supplier must furnish detailed information on all components so the module can be repaired should the need arise. The Navy has also established aspecial category for modules equivalent to the standard throwaways but lacking applications outside the system for which they are designed. Depending on cost data that remain to be developed, such units may or may not be thrown away when they fail.
An important element in standard hardware's versatility is the design of the module. After a great deal of study, the Navy decided on abasic size: 2.62 inches wide, 1.95 inches high, and .29 inches thick. Height is not avariable, but width and thickness can be increased in increments of 3.0 and .3 inches, respectively.
Components like transformers for power-supply modules sometimes lead to deviations from the basic configuration. In such cases, design waivers are granted for thickness.
Lockout. Avariety of key pins are used to prevent a module's being plugged into the wrong spot. For example, adelta arrangement would effectively preclude aunit's being jammed into a female receptacle with half delta guides.
A basic module width has 40 male contacts arranged in two rows. Contacts are spaced one-tenth of an inch apart in the grid pattern.
Circle 177 on reader service card-->

We guarantee

performance of

our vacuum

production

equipment. We make systems for thin film deposition,

Cold weld, encapsulation system built or Western Electric, seals 1000 crystals in every 8-hour shift; pumpdown, 37 sec. to 10 -7 Torr; full cycle <75 sec.

for coating, and for encapsulation.

When yo Jbuy asystem from us,

you get aturnkey operation; you get

ateam cf design engineers who

specialize in vacuum technology;

you ge: fixtures and components

to suit your specific processes. And

you get the reputation of amajor

corporation that assures backup

service long after the system

is Vistalied.

If your production plans include

processing in vacuum, call on us:

Varian Vacuum Division, Palo Alto,

California; Zug, Switzerland;

Georgetown, Ontario.

Varian Vacuum has the

resources and

experience to

tackle tough

vacJurr, processing jobs!

varian
vacuum divisityl

When you hit the button, everything in the vacuum
processing system works.

At last ...VERSATILITY in a reed relay

The Series 3500 terminals...

has printed circuit board mounting on 1 inch x .100 inch centers.

... or, when we slide a plate into our bobbin mold, circuit board mounting pins on 1 inch x .150 inch centers and is called Series 3600...

it has printed

Both versions use our new assembly without requiring strip and its extra welds.. .

Flextop terminal to give stress-free reed an intermediate nickel "ribbon"

But, when you need a relay that plugs in and out without fuss, or just want an independent source for Berg Pin mounted relays, we add adapter blocks ... and fill all your needs from stock!

Either way you get a big bore bobbin that holds even the largest "miniature"

reeds without sacrificing its unique fully recessed coil exposed magnet wire and

low .350 inch profile, and terminals that eliminate intermediate coil leads.

Hi

Call, write or check the reader service card for your copy of HI -G bulletin .160. If you need application engineering assistance, an experienced Hi-G representative awaits your call. Telephone: 203-623-2481.
SPRING STREET & ROUTE 75 / WINDSOR LOCKS, CONNECTICUT 06096

178

Circle 178 on reader service card

Circle 179 on reader service card -÷

That's right. It's a commercial connector. Our Molex Standard. Millions are finding their way into some of the most exciting circuitry man can imagine. For that's our business: creating connectors that simplify wiring. Speed production. Assembly. Installation. Servicing. For the men who are looking for new ideas and ways to cut ccsts. in the area of one circuit to sixty connections or more, Molex has the Droduct And the design and engineering impabilities to solve the most complex wiring z.nd production problems ... fast! We'd like to talk to you about it. If you would like a free sample of our Molex connector, please write or phone (31.2) .E9-455C. You
molex can make con-
nections at ...
MC VEX PRODUCTS COMPANY Downers Grove, Ill. 50615

Vital. High Reliability.

In the bone-snapping cold of outer space electronic components are on their own... they must perform reliably. Increasingly stringent demands mean push-
ing technology to its limit. McCoy has traditionally been aforemost manufacturer and supplier of the
highest quality crystals, filters and oscillators for NASA and U.S. military services. To maintain this position has required constant advances in tech-
nology. Our new research and development laboratory (with White Room facilities)
is being built now to help McCoy meet the demand for even better products in the future. Coordination of engineering, manufacturing, quality control and management will keep us in the forefront in providing reliable products
to meet customer specifications. When high reliability components are needed, turn to the leader... McCoy.
Engineering assistance is available of course. Write now for our new High
Reliability literature.

OSCILLATORS CRYSTALS

FILTERS

McC0Y ELECTRONICS COMPANY

MT. HOLLY SPRINGS, PENNSYLVANIA 17065

Tel. 717-4E16-3411

TWX: 510-650-35413

a subsidiary of OAK ELECTRO/NETICS --cireaTe

180

Circle 180 on reader service card

Circle 181 on reader service card-*

T2L
RAYTHEON
T2L
RAYTHEON

TRAYT2HELON TRAYT2HELON

T2L RAYTHEON T2L RAYTHEON

T L 2 RAYTHEON

T2L

RAYTHEON

T RAY2 THEL ON

r.L RAYTHEON

PL

T L 2

RAYTHEON

RAYTHEON T2L

PL

RAYTHEON
PL
RAYTHEON
T2L

T 2L RAYTHEON

RAYTHEON
T2L

T 2L RAYTHEON

RAYTHEON

T2L

RAYTHEON

T2L

RAYTHEON

llfeatures off-the-shelf availability

it's only logical!

All RAY Iand RAY II types are available, including dual J-i< fl p-flcps (RF 100, RF 110, RF 120, F.F 130
Series), single J-K flip-flops (RF 200, RF 20, RF 250, RF 260 Series), gates aid drivers.
Our T2L inteciratec circuits match up to the toughest electrical test limits in the industry. They feature our exclusive high alumina glass to Kovar seal (guaranteed to 5x 10 -8 cc/sec Helium). And they're available in quantity now. Order you's from your local Raytheon
Distributor. It's only logical! Raytheon Company, Semiconductor Operation, 350 Ellis Street,
Mountain View California 94040 (415) 968-9211
RAYTHEON

Will Scotchpai win the Ester award for the best film of the year?
Based on the quality of polyester films, 3M's SCOTCHPAR should win at least as many votes among electrical manufacturers as the "big name" film. There's nothing better than SCOTCHPAR for capacitors. And there's nothing better than SCOTCHPAR as insulation for transformers, motors, wire and cable. We have it in thin films and thick films. SCOTCHPAR has high dielectric strength, great temperature stability, resistance to moisture and solvents. It's thin, tough, flexible and durable. If you're going to use polyester film instead of aconventional insulation--and you should, to cut costs, save space, and improve product performance--vote for SCOTCHPAR. If you want SCOTCHPAR that's heat sealable, the name is SCOTCHPAK.® Avote for SCOTCHPAR is avote for quality and adaptability. 3M Company, Film & Allied Products Division, 3M Center, St. Paul, Minnesota
"1°1Scotchpaè 301

182

Circle 182 on reader service card

Electronics April 15, 1968

These are specialized TRACOR instruments designed for gour specific needs.
FREOUENCY STANDARDS

RUBIDIUM FREQUENCY STANDARD 1 x 10 -1 °freq 2x10 -" stnd dev/yr
use Reader Service #315.
ULTRASTABLE CLOCKS AND DIVIDERS

CRYSTAL STANDARDS

5x10 -"/24 hours

1x 10 9/24hours

5to 0.1 MHz

LOW COST HOUSE STANDARD

use Reader Service #316.

use Reader Service #317.

VLF RECEIVERS--FREQUENCY/PHASE COMPARATORS
If

JA I

VLF TRACKING RECEIVER/COMPARATORS Continuous tuning 3.00 to 99.5 kHz
use Reader Service #321.
NOISE ANALYSIS

LINEAR PHASE/TIME COMPARATOR 1nanosecond time resolution 0.01 cycle phase resolution
use Reader Service #322.

FREQUENCY DIFFERENCE METER difference to 1x10", error multiplied by 10 4.
use Reader Service #323.
OMEGA NAV SYSTEMS

CONTINUOUSLY- VARIABLE PASSIVE FILTERS 15 Hz-672 kHz
use Reader Service #324.
NORTHERN SCIENTIFIC. INC.

A EQUALIZERS/SPECTRUM GENERATORS
Up to 40 73-octave increments
use Reader Service #325.
ASTRO -SCIENCE CORP.

VLF/ OMEGA NAVIGATIONAL SYSTEMS For broad-area navigation
use Reader Sery ce #326.
WESTRONICS INC.

,i.ezerkile.,

_

DIGITAL

CZ 1 ·te .-*-« . MEMORY

.

·...·,,, L,,AaOnnSadClIyPzLuelLrsOseSHCeOiPghEtS

use Reader Service #327.

ASTRO -SCIENCE MULTI-CHANNEL AIRBORNE INSTRUMENTATION TAPE RECORDER/REPRODUCERS
use Reader Service #328.

, '
MULTIPOINT AND CONTINUOUS PEN CHART RECORDERS
use Reader Sers ce #329.

For a short-form catalog of TRACOR instruments, please use Reader Service #330.

Industrial Instruments Division

IA-1078
Electronics April 15, 1968

6500 TRACOR LANE. AUSTIN, TEXAS 78721 (512) 926-2800

183

New! Solid state voltage sensors protect processes and equipment.

Positive response...plug-in convenience. P8A3 quality, too!

613
-
Adjustable Pick-up and Drop-out

Sound an alarm, start or stop a motor, activate or cut off a system automatically. with P&B's new series of voltage sensors. A sensitive solid state circuit« "reads" changes in voltage. Over or under voltage deviations greater than predetermined levels cause an internal relay to operate ...in 25 ms or less. Dropout or pick-up is positive, and loads of 3amperes at 120V AC resistive can be switched.
Three types are available: one with adjustable pickup and drop-out; one with fixed pick-up and adjustable drop-out; one with fixed settings for both pickup and drop-out. All models are available for either AC or DC operation. All have octal plugs.
Single lot prices for standard models, available from leading electronic parts distributors, range from $22.70 to $32.50. Today, call your P&B representative for complete information.
Specifications Sensing Current Drain: Maximum of 3ma.
Maximum Current Drain: After sensing: 30 ma.
Accuracy of Set Point: 1% after initial setting.
Reverse Polarity Protection: Yes, on DC types.
Operating Temperature:-40°C to +55°C. Load Switching Relay Contacts:
2Form C (DPDT). Rating: 3amps 28V DC
resistive; 120V AC resistive.
Mechanical Life: 10,000,000 operations.

CS 38 Series

184

Circle 184 on reader service card

Fixed Pick-up and Adjustable Drop-out
POTTER s. BRUMFIELD
Division of American Machine & Foundry Co., Princeton, Ind. 47570 Export: AMF International, 261 Madison Ave., New York, N.Y. 10016
Circle 185 on reader service card--->-

Get ideas here on flexible cables.

CERRO WIRE & CABLE CO.
i· .v.5.o.0 0 0 IGERRO CORPORATION

CERRO Fl EX . E goDuers

TECHNICAL SERVICE
DEPARTMENT

330 eosToni POST RD.
OLD SAYBROOK. CONN. (203) 388 4676

Get help here when you need it.

Our catalog on flat flexible cables and printed wiring will show you how to cut the cost, size and weight of your products. It will stimulate your thinking about this modern way to package electronic circuitry. A Cerro-Flex® Technical Man can help you design your flexible circuit and fulfill your needs from our modern plant. Send today for acopy of the Cerro-Flex Flat Cables and Circuits Catalog.
Cerro-Flex Products, Cerro Wire & Cable Co. 330 Boston Post Road, Old Saybrook, Conn. 06475
Gentlemen: El Please send me a copy of "Cerro-Flex Flat Cables and Circuits." [] Please have a Cerro-Flex Technical Man call.
Name Title Company Address
CERRO
WIRE & CABLE

The

Wait

ACTIVE FILTER

Reducers! ···

New

5X15-BPIP5R00

Active Filters from

BURR-BROWN ACTIVE FILTER

BURR-BROWN

5715-BPIP-5R00

At Burr-Brown, computer-aided design and new modu-
lar assembly techniques combine to give you faster delivery of active filters ...in most cases within two weeks of your order. And, you specify the exact performance you want from Burr-Brown's new line of 5 Hz to 20 kHz units. Custom units are available with frequen-
cies as low as 0.1 Hz and as high as 100 kHz.

A variety of active filter types and response characteristics are available including:

TYPES
D low-pass D high-pass D band-pass D band-rejection

CHARACTERISTICS
D Butterworth Tchebyscheff
D Bessel (linear phase)

Since the heart of the filter is the amplifier, Burr-Brown has the very finest building blocks, including its own IC op amp (patent pending). Because of the outstanding performance of Burr-Brown op amps you get active filters with superior characteristics at the lowest possible prices.

You also benefit from Burr-Brown's industry-leading technical staff. For the same experts who authored the Active RC Network Handbook, the basic industry reference on the use of operational amplifiers in filtering applications, supervise Burr-Brown's active filter facilities.
So, if you use active filters and you want afast, dependable source of supply, call on Burr-Brown. You'll find Burr-Brown knows a little more and does a little more, because Burr-Brown has more to work with.
NEW 12-PAGE ACTIVE FILTER CATALOG
For your copy of the new applications-oriented Burr-Brown Active Filter Product Bulletin, contact your local Engineering Representative or use this publication's reader-service card. For Immediate Applications As sistance: simply phone (602) 294-1431 and ask to talk to your Burr-Brown Applications Engineer.

BURR-BROWN
RESEARCH CORPORATION
International Airport Industrial Park · Tucson, Arizona 85706 TELEPHONE: 602-294-1431 · TWX: 910-952-1111 · CABLE: BBRCORP

BB

Operational Amplifiers Instrumentation Amplifiers
Function Modules Active Filters Analog Simulators Geophysical Instruments

ENGINEERING REPRESENTATIVES: ALABAMA, HUNTSVILLE (205) 534-1648 /ARIZONA, PHOENIX
(602) 254-6085 / CALIF., LOS ANGELES (213) 665-5181, SAN FRANCISCO (408) 244-1505 / COLS., DENVER (303) 388-4391 /CONN., EAST HARTFORD (203) 874-9222 / D.C., WASHINGTON (SEE MARYLAND) / FLORIDA, ORLANDO (305) 425-2764 / ILLINOIS, CHICAGO (312) 286-6824 / LA., NEW ORLEANS (504) 888-2266 / MD., SILVER SPRING (301) 588-8134 / MASS., BOSTON (617) 245-4870 /MICH., DETROIT (313) 358-3333 /MINN., MINNEAPOLIS (612) 781-1611 /MO, ST. LOUIS (314) 524-4800 /N.C., GREENSBORO (919) 273-1918 / N.J., CAMDEN (215) 925-8711

/ N.M., ALBUQUERQUE (505) 255-1638 / N.Y., ALBANY (518) 436-9649, BINGHAMTON (607) 723-9661, MT. VERNON (914) 968-2200, NEW HARTFORD (315) 732-3775, ROCHESTER ((716) 473-2115 / OHIO, CINCINNATI (513) 761-5432, CLEVELAND (216) 237-9145, DAYTON (513)
277-8911 / PENN., PHILADELPHIA (SEE CAMDEN, N.J.), PITTSBURGH (412) 243-6655 / TEXAS, DALLAS (214) 357-6451, HOUSTON (713) 774-2568 / UTAH, SALT LAKE CITY (801) 466-8709 / VIRGINIA, (SEE MARYLAND) / WASH., SEATTLE (206) 767-4260 / CANADA, DOWNSVIEW, ONT.,
(416) 636-4910 -- MONTREAL, QUE., (514) 739-6776 -- OTTAWA, ONT., (613) 725-1288 --
VANCOUVER, B.C., (604) 298-6242

186

Circle 186 on reader service card

Electronics April 15, 1968

Military and aerospace equipment demands proven
reliability. That's why. Dytronics specifies capacitors

of MYLAR

I)vt ronics Co.. Inc.. of Columbus. components we sel ecl Ilundreds

Ohio. ulakes Primary Phase Angle

of our Primary Phase Angle Standards

Standards Ihat are HMI(' all 0 er the

are ill military usage. and ve are not

wield in all temperature extremes.

.iware of asingle failure of capacitors

Each precision unit uses 70

of MYLAR...we lei!! that this is

capacitors of NIY

'

evidence of both the reliability

polyester film. Why MUM« Here's what Paul

AIL

·

t #

`(lid performance of NIYI.AR

.1nd

find that capacitors of

Ryan, President. had to say: "Military and major

14440,.

NIYI.:\ I: cost about the same as those made of paper."

aerospace facilities cannot

IMI.:\Roffers thermal

afford equipment failure.

4.

stability from --70 ° W +150 C.

and we must be sure of the

plus excellent resistance to

most chemicals and moisture.

MYLAR has high tensile and dielectric strength. Its unexcelled thinness has enabled manufacturers to reduce size and weight in capacitors.
Isn't that reason erough for you to consider capacitors of NiYIAR in your designs? For additbnal information write to Du Pont, which offers the thinnest, most versatile range of capacitor dielectric materials available. Address: Du Pont Co., Room 5852B, Wi Iuni ngton. Delaware 19898.
o1J P110' MYLAR·

Electronics April 15, 1968

A typical part of the Primary Phase Angle Standard shown above with four capacitors .)f MYLAR (green).

Circle 187 on reader service card

187

NOW plug in up to 2048 bits, at aspeed of
MHz for less than 50 per bit, with built-in TTL interface.

New Low Cost CORNING Digital Glass Memory Modules.

Fast
Available Frequencies
4 MHz 8 MHz

Available Delay Time

64 iisec.

128 ttsec.

256 Bits 512 Bits

512 Bits 1024 Bits

256 /sec.
1024 Bits 2048 Bits

These are standard. Custom modules available up to 4096 bits and up to 16 MHz.

Easy. Just plug one in and you have serial storage. All the circuitry to interface with TT Logic is built in. You need no special power supplies, no voltage level shifters.
Low Cost. In the 1000 module bracket, for 2048 @ 8MHz,

each bit costs less than a nickel. More modules--less cost. Even in 100 piece quantity, each bit costs less than a dime. And it's your only cost.
Stable. The medium is proven CORNING Zero-TC glass.
Here now. These are performing products, not promised potential. Write for full data sheets, or to see our man with samples. Corning Glass Works, Electronic Products Div., Advanced Products Dept., Raleigh, N.C. 27602. Telephone (919) 828-0511, Ext. 262.
CORNING
ELECTRONICS

188

Circle 188 on reader service card

Electronics April 15, 1968

coHmopawndieosmmoostve alightning-fast, long-memory, high-capacity computer?

They choose an on-time, precision-planning,
big-capacity van line. Allied Van Lines safely moves more
computers (with long memones) than any other mover.
Call the confident Allied Agent in your area.

Circle 189 on reader service card

ALLIED VAN LINES

VOL. I ISSUE XVI

Ze2

t;n1tetin WHETHER or not you use Designer's Choice Logic, you have to admit that Signetics' idea of guaranteeing cross-

family compatibility in

integrated circuits can

PUBLISHED BY SIGNETICS:

Gil THE RESPONSE/ABILITY COMPANY

save you time and money in design.

NEW IC NIXIE DRIVER GETS UNGLOWING REPORT

Guaranteed 67V Breakdown

Signetics Corporation today announced the first monolithic IC Nixie
Driver that permits Nixie* tube operation without excessive background glow and does not require any discrete external components for interfacing. "We've whipped the problem of getting astate-of-the-art 2.5-ohm centimeter
process into production, so we can

Pre-bias Voltage vs. Current Characteristics of atypical NIXIE Tube.
guarantee a67V breakdown," acompany spokesman said.

Officials also said that the new device, designated 8T01 Nixie Decoder/ Driver, is the only one of its kind that will interface directly with all commonly used DTL and TTL circuits and drive Nixies directly. The new member of Signetics DCL family is offered in a 16-pin silicone DIP.
When told of this new device from Signetics, acompetitive manufacturer stated, "Dammit."
*Nixie is aregistered trade mark of the Burroughs Corp.

Big shift to new Shift Register
Unique Device Announced
"Your new shift register is the answer to my prayers."
That quote, from aDallas designer, is typical of the response to Signetics' introduction of anew 4-Bit Shift Register in the DCL line, according to Bill Slaymaker, a Signetics Product Marketer.

"This device has aunique organiza-

tion and functional capability," Slaymaker commented.
The new 8270/8271 4-Bit Shift

Signetics announces new publication

Register is fully synchronous and offers parallel or serial input and output. The

Signetics launched a new publication today, the DCL Bulletin. As you can

device operates at clock rates up to 20 MHz and has amass reset line (in the 8271, a 16-pin configuration) that is independent of the clock. A unique feature is separate load and shift con-

see in the masthead the first issue is
the 16th issue, the first fifteen issues
having never been published. DCL has been famous and well-loved since
1966, so it would be just plain silly to call the first issue the first issue.

trols that make it unnecessary to gate

the clock to inhibit the shift, thus elim-

inating clock skew problems. Power consumption is 40mW per binary.

TODAY'S BUZZ WORD

The 8270/8271 is supplied in 14 lead flat pak, and 14 or 16 lead silicone DIP in both full MIL and industrial

"Designer's Choice Logic" You didn't expect it to he "Fairchild"?

temperature ranges.
vt

FOR SPEC SHEETS

1511271 ONLY)
eLoacip

DC

Do

Specifications on our new Nixie Driver and Shift Register are now available.
Send for information on our complete DCL line. Write: Signetics, 811 East Argues Ave., Sunnyvale, Calif. 94086.

Signetics new 8270/8271 4-bit shift register. Comes in 14 lead flat pack or DIP and 16 lead DIP.

ioy1 (1271 ONLY)

SIGNETICS SALES OFFICES: Fort Lee, New jersey (201) 947.9870; Syracuse. New York (3)5) 469-1072: Richardson, Texas (214) 231.6344; Beverly Hills, California (213) 272-9421; Garden Grove, California (714) 636-4260: Wakefield, Massachusetts (6)7) 245.8200; Silver Springs, Maryland (30)) 946 6030; Collingswood, New Jersey (609) 852T7864; Clearwater, Florida (813) 726.3734; Rolling Meadows, Illinois (312) 259.8300; Sunnyvale, Cali. turnia (408) 738.2710.
DISTRIBUTORS: Compar at all locations listed below. Semiconductor Specialists. Inc. (312) 279.1000; Terminal Hudson Electronics (212) 243.5200: Wesco Electronics (213) 684.0880; Wesco Electronics (405) 968.3475; Hammond Electronics (305) 241.6601; Aune) Electronics Corp. of Massachusetts (6)7) 272-3060; Pioneer Standard Electronics Inc. (301) 427-3300; Kierululf Electronics (206) RO 3.5510; G. S. Marshall (213) 684.1530.
DOMESTIC REPRESENTATIVES: Jack Pyle Company (415) 349.1266. Compar Corporation at the following locations: Alabama (205) 539-8476: Arizona (602) 9474336; California (213) 245.1172; California (415) 697.6244; Colorado (303) 781.0912; Connecticut (203) 288.9276; Florida (305) 855.3964; Illinois (312) 6924)25; Maryland (30)) 484.5400; Massachusetts (617) 969 7140; Michigan (313) 35/.5369; Minnesota (612) 922.7011: Missouri (314) 542.3399; New Jersey (609) 429.1526; New Mexico (505) 265.1020; New York 1518) 436.8536; New York (6071 723 8743; New York (516) 92).9393; North Carolina (919) 724.0750; Ohio (216) 333.4120; Ohio (513) 878.2631; Texas (2)4) EM 3.1526; Texas (7)3) 667.3420: Washington (206) 763.1711.
INTERNATIONAL SALES: France, Germany, Italy, Belgium, Holland. Iuxemburg. Spain- Sovcor Electronique, It. Chemin de Ronde. le Vesinet. (S. 0-0.1 France. United Kingdom. Ireland. Sweden, Denmark. Norway, Switzerland, Austria, Portugal -Electrosil Ltd., Lakeside Estate. Colnbrook.By.Pass Slough. Buckinghamshire, Great Britain. Australia --Corning, 110? Plaza Building, Austialia Square, Sydney, N.S.W. 27.4318. Canada -Corning Glass Works ol Canada, Ltd., Leaside Plant. Ontario. Canada (416) 421.1500. ISrael-Optronix, P.O. Box 195, Ramat Gan, Israel 714 437. tapan ASAHI Glass Co., Ltd., Corning Products Sales Leg No. 2. 3-Chome Marunouchi. Chiyoda.ku. Tokyo, Japan.

190

Circle 190 on reader service card

Electronics ,April 15, 1968

Amphenol just joined the 50 billion mile club

Sonic 54,000,000,000 miles ago Amphenol connectors
started flying with the first commercial jet airliners. This experience helps us improve our connectors to meet rigid specifications on the new jets.
Our report on the Boeing 727 is available now. It documents reliability of MIL-C-5015, MIL-C-26500, MIL-C-26482, coaxial and rack and panel type con-

nectors. Our report gives performance data on these connectors and establishes various failure modes.
For a free copy, please request our report "Jet Aircraft Connector Field Failure Data" on your
company letterhead. Amphenol Connector Division, Amphenol Corporation, 2801 South 25th Avenue, Broadview, Illinois 60153.

Circle 191 on reader service card

AMPHENOL

Barnstead elephant-sized demineralizers work for peanuts
Barnstead industrial demineralizers give you large quantities of process water at unusually low cost. Take this Barnstead Two-Bed model used by a major metals producer. It removes heavy concentrations of calcium and other troublesome impurities from 2,000 gallons of water per hour -- at an operating cost of only afraction of acent per gallon. (Excluding
initial demineralizer cost.) Operation, particularly regeneration, is easy and economical. A simple one-handle valve for all steps and a visible waste trough help prevent resinwasting mistakes. An automatic purity controller assures water quality and tells when it's time to regenerate. Do you have a big demineralizing job to do? Write for the Barnstead Catalog 160 describing demineralizers from 5to 3,000 gph.
Marristead
A DIVISION OF RITTER PFAUDLER CORPORATION
225 Rivermoor Street Boston, Massachusetts 02132

192

Circle 192 on reader service card

Electronics April 15, 1968

April 15, 1968
New Products

Corn puters
Punched cards on the ropes?

Fast, compact machines can transcribe data directly onto tape; optical character and magnetic readers are also in contention

By Wallace B. Riley
Computer editor

The admonition, "Do not bend, fold, staple or mutilate this card,"
may eventually take its place alongskie such expressions as "Twentythree skiddoo," and "All the Way
With LBJ." And "eventually" may be just around the corner. Ses'-
eral recent developments indicate
that the days of the punched card as a computer input medium may be numbered. Two machines, now on the market, can transcribe data directly from a keyboard to magnetic tape; an experimental mag-
netic-card system was recently announced, and cathode-ray tube units and optical character readers
are arousing more and more interest in the computer industry.
Long run. The punched card as a medium for moving data in and out
of automatic equipment is 81 years old. The present standard format-
80 columns and 12 rows of positions for rectangular holes in a 0.007-inch-thick card 7% by 31 /4
inches--has remained unchanged
since 1928. With this kind of longevity, the
punched card isn't likely to disap-
pear completely for many years. In fact, the number of punched cards used each year has been increasing an average 11% since 1962, almost
entirely because of the explosive growth of the computer industry.

For one thing, 80% to 90% of the
field relies on punched cards for input. For another, the cards cost
only about a tenth of a cent But the growth is expected to taper off to perhaps as little as 2% a year
within five years because new kinds of machines are 'appearing, and in-
terest is growing in other media such as disk packs--removable magnetic disks that share the bulkstorage advantages of magnetic tape but have the random-access characteristics of large disk files. Such developments are reducing
the number of cards consumed per user. But for the moment, this at-

trition is more than offset by the increase in the number of users.
I. Bill of particulars
Interest in alternatives to the punched card is heightened by its numerous disadvantages, some of which are critical now that faster and faster computers are being produced. Among the drawbacks:
One shot. A card can be punched only once. If akeypunch operator makes a mistake, he has to start over on anew one.
Cozy. One card contains amaximum of 80 characters of data, except when unusual special codes

ABCDEFGHIJKLmNOPORS7UV'AU 111111111
111111111

0123456789

(%**.S./-0

1

1 1

III

mCCRAw-HILL. INC.

II 1 II

1 11

11111 I

II llllllll 10)000010111111118010110000000010000A001001C0801 10000 1 00011 1 000000080

I, 14

1

·

, rue, wums enw uvuo

., · .1.

221272/222212222222127222222223322122222222222223212232222 22 :222222222032223222 31313333000113330033101300030000101133330030030101111 130001 :1 331 :: 333 111 333 11 0333

44141

1

1

1

IIi 4Lll 4

i 3 I 1 ll 44 4ll4l4 44 44l 1144

555$51555555551S$55555155555555555555155SS555555555555535 5 555555555,555 155 $555

Ii66611601661811616iiiiiiiiii66116161%iiiii66611566666iiii1 66666 Siiiiiiiii

7111117117/1111117/117771117/71111111 1 11111117111/7111311/1 10 1 11171111117171 /117

111566111

I

11111111611111166musiiiistsillis

llllll 1111,911111,191111MIMMIMIII411,91 , 19 9 119 ,9 lllll 4991919 , 1911919M

Code. In aconventional 80-column, 12-row punched card, asingle punch in
one of the nine numeric rows or zero zone represents one of 10 decimal
digits. Numeric plus zone punches represent alphabet letters. Other combinations stand for avariety of special symbols.

Electronics IApril 15, 1968

193

In and out. The removable magnetic tape cartridge in Communitype's data communication system has capacity of 180,000 characters or 30,00C words.
Quick trick. With Honeywell's Keytape, data can be transcribed directly orto computer-ready magnetic tape through akeyboard. 194

are used. When record lengths require more than 80 characters, additional cards are necessary. However, only 60 to 70 characters can be used per card; the rest of the space is needed for codes that identify cards containing parts of asingle record.
Inefficient. The 12-row Hollerith code used on most punched cards is highly redundant; only 64 characters are defined, out of apossible 4,096--an efficiency of about Wz%.
Slowpoke. Most card readers used as input devices with computers have a maximum speed of 400 to 800 cards per minute; afew can get up to 2,000 cpm. Even with every card packed full of data, the maximum possible input is only 2,667 characters per second--at least 40 times fewer than today's standard magnetic tapes. As aresult, large-scale systems usually include one or more small peripheral computers that transcribe card data onto tape in a separate process. This lets the central processor work directly with magnetic tape.
Closet case. Any significant amount of data kept on punched cards for future use takes up alot of storage space and is heavy.
Slow shuffle. Dropping adeck of cards may require a complete resorting--this means lost time, extra handling, and the possibility of damage or contamination of the cards.
Fallout. Cards tend to generate dust and lint in the machines that handle them. Specifications can minimize but not eliminate such difficulties.
Down time. A damaged or wornout card can jam the machine processing it; the process must be stopped and a new card punched and inserted in its proper place before the job can be resumed.
Redeeming virtues. Of course, the punched card does have its good points. It can carry any kind of information, and the punches can be read visually if one knows the code. It can be read into the machine with only a simple computer program. What's more, the punched card has some actual advantages over other media. It can be separated from the file, mailed, or otherwise handled individually, and restored to the file at any time.
And in many applications cards can be economically processed only
Electronics IApril 15, 1968

Punched cards then and now
During the 1880's the records of the Census Bureau were still being compiled by hand. But the growth of the U.S. made it apparent that existing techniques wouldn't provide thé results of the 1890 census until yell after 1900. As a result, a bureau statistician named Herman Hollerith set out to develop a mechanized tabulating system. His machines, first tested in 1887, were controlled by cards with three rows of 32 punch positions along the top edge, and three more rows along the bottom--a total of 192 possible positions for holes.
Stepping stone. The processing of the 1890 census with Hollerith's machines was so successful that he founded the Tabulating Machines Co. to develop and market the machines commercially. About 20 years later Hollerith's firm merged with the Computing Scale Co., amaker of butcher scales, and the Time Recorder Co., which produced time clocks for factories. The corporation was named the Computing, Tabulating, and Record-
ing Co. The merger wasn't particularly successful, and in 1912 anew president
was brought in. He was 40-year-old Thomas J. Watson Sr., who had just left his job as sales manager at the National Cash Register Co. after a falling out with the chairman of the board. Watson succeeded in improving the company's fortunes and it prospered; in 1923 it changed its name to the
International Business Machines Corp. Solo. Then and for many years thereafter, IBM was the only company
making card-controlled electric accounting machine. In addition, its name continues to be synonymous with punched cards. The company made the switch to electronic computers in the early 1950's over the objections of the elder Watson, who kept effective control of the concern until shortly before his death in 1956. Nevertheless, the company continued to turn out electric accounting machines, which still account for a substantial part of sales, although they have been largely eclipsed by computers.

once and then discarded.
II. No bargain either
The key punch, amachine used to transfer data manually from source documents to punched cards, also has drawbacks. It's a mechanical device subject to breakdowns and is very noisy and tiring to operate. The machine can't check the punched data; a separate verifier machine, usually requiring an additional operator, is necessary to ensure accuracy. Physically, the verifier is almost identical to the key punch, but has mechanical "feelers" instead of punches.
Only the International Business Machines Corp. makes key punches. A 1956 consent decree with the Justice Department requires ism to make its design specifications available to anyone who wants, to build equipment to interface with ism computers, but no one had taken advantage of this opportunity. However, several companies make other kinds of equipment that's compatible with IBM gear.
Lilliputians. The company insists that it has competition in this area. But only a half dozen or so firms make equipment for punching holes in cards, and such products--

with one exception--are all portable, hand-operated devices that wouldn't be suitable for volume production. For example, Taller and Cooper Inc., Brooklyn, makes a portable printing punch that works like a toy typewriter. A dial turns
to the character to be punched, and abar simultaneously drives the corresponding punch knives through the card and prints the character at the top of the card just like IBM'S key punch does. The Taller and Cooper machine even has atabulator that permits skipping over several columns at once.
The printing punch is marketed by Taller and Cooper and by the Wright Line division of the BarryWright Corp.; an agreement with the National Cash Register Co. is being negotiated. Taller and Cooper
is also developing the only machine that has anything like the capability
of an ism key punch; it looks and works like a typewriter. The machine, an electrified version of the portable printing punch, is being developed under acontract with the U.S. Navy, which needs acompact and versatile unit to use in submarines and destroyers. It will be commercially available for about $2,500 in about six months.

Electronics April 15, 1968

this is an antenna!
That's right! Concealed within this rugged rear view muror is an omnidirectional V.H. F. antenna for the 148-174 Mc band. The Sinclair Mobile Mirror Antenna defies detection ...prevents vandalism... eliminates special antenna mounting. Independent tests prove efficiency equal to -- or better than a1/4 wave whip. V. S.W.R. is less than 1.5 to 1 at design frequency. Clip the coupon for FREE literature, including test data and prices.
SO'S this
It looks--and mounts--like a standard car radio antenna. Yet it conceals aragged V.H.F. two-way radio antenna for the 148-174 Mc band. Each Sinclair Disguised Whip Antenna is perfectly "matched" to your specific frequency. This exact matching, combined with a2.5 db gain, insures greater efficiency than any other disguised antenna now on the market. Clip the coupon for FREE literature, test data and prices.
sincLair ramo LaBoraTorues

FREE LITERATURE

TO: SINCLAIR RADIO LABORATORIES, INC. 676 Ensminger Rd., P.O. Box 23 Tonawanda, New York 14150

Name .

Title*

Company .

Address .

City*

State .

Zip*

Circle 195 on reader service card

195

ONLY 0.8 dB INSERTION LOSS
FROM ONLY 0.1 CUBIC INCHES OF
Telonic's new Miniature Bandpass Filters offer two prime advantages to the designer--small volume and large performance. The 'scope trace above shows the actual bandpass of a Model TSA Filter that occupies .2 cu. inches, weighs less than 1 /2 ounce, and can out-filter units 10 times its size. Insertion loss is only .8 dB, 30 dB form factor is 4.2, and the 3dB bandwidth is 45 MHz wide.
SERIES TSA--CENTER FREQUENCIES 200 MHz to 600 MHz
A coupled resonator type using .01 dB Chebyschev distribution. 3 dB bandwidths may be specified from 1 to 15%. Insertion loss is minimal at any frequency. Dimensions: 1 / 4 "x9/16" x 11 /2 "-3½".
SERIES TBS--CENTER FREQUENCIES 200 MHz to 2300 MHz
A tubular type filter with 2 ----liFfeeereime to 8 sections providing 3dB bandwidths from 1.5 to 20%. Low insertion loss and VSWR in the passband. Dimensions: 1 /4 "diam. x 11/ 2 "-5".
COMPLETE SPECIFICATIONS ON BOTH SERIES INCLUDED IN CATALOG 101A--
SEND FOR YOUR COPY.

.4.-
eeENGINEERING CO. TAELDOIVNIIScI01 NND4t3.1FSTRIES, INC.
BOX 277 · LAGUNA BEACH, CALIF. 92652 · TEL.: 714 -494-9401 · TWX: 910 -5964320

196

Circle 196 on reader service card

.not even Univac
builds key punches...
IBM's electrically driven key punch is a sophisticated device; it feeds cards automatically and is capable of skipping and duplicating under control of a program drum that can be set up for any data format. The company's design and service have proved so good that no one has seen any percentage in taking on the giant in this area. And with the advent of machines that bypass punched cards and the prospect of adeclining market, it's unlikely that anyone will want to develop anything in the future.
Dead issue. Not even the Univac division of the Sperry Rand Corp. builds key punches. Some years back, however, it did turn out machines that punched round holes in 90-column cards used in electric accounting machines and computers like the 1004 and 1050. But now that Univac's 9000 series of processors uses 80-column, mm-format punched cards, the company has left the key punch field altogether.
III. New directions
Three years ago, a small company in upstate New York, the Mohawk Data Sciences Corp., making the first real effort to overcome the disadvantages of punched cards, brought out its data recorder, amachine with akeyboard almost identical to that of the key punch.
The operator keys in data as he would with a key punch, but the data is stored in acore memory until the record is completed. The data is then written at 200 bits per inch on astrip of seven-track magnetic tape that can be processed directly on acomputer. The record can be verified on the same machine immediately after writing or later; errors can be corrected immediately without starting the record over. One reel of rolled-up tape, 2,400 feet long, taking up about a tenth of a cubic foot of storage space, can hold as much data as about 36,000 cards requiring more than 40 times the storage space. (This holds true if the data is recorded on the tape in essentially the same format as on the cards.) More sophisticated techniques can greatly increase the amount of data stored on the tape. And the tape
Electronics IApril 15, 1968

HERE'S HOW...
THE ELECTRONIC INDUSTRY IS USING THESE FAMOUS ULANO FILMS IN ULTRAMINIATURE MASK TECHNOLOGY AND COMPLEX PRINTED CIRCUITRY

Cut a piece of the desired film large enough to cover area to be masked. Tape it down firmly at the top with dull-side up.

r

With sharp blade, outline the areas to be masked. Do not cut through the backing sheet. The Ulano Swivel Knife does the jab quickly, easily.

Using the tip of the blade, lift up a corner of the film thus separating it from the backing sheet.

RU BYLITH'TM' AMBERLITH'
HAND CUT MASKING FILMS FOR THE GRAPHIC ARTS
ULANO RUBYLITH ... a revolutiona:y knife cut red film is laminated to a stable transparent plastic backing sheet. The red film is "light safe" so that when contacted to a sensitized emulsion and exposed to asuitable light source, light passes through the cut-out portions only ...not through the red film. · The polyester backing is absolutely stable ...insures perfect register. U Special effects such as crayon tones, paste ups, berday sheets, and opaquing are easily combined with versatile ULANO RUBYLITH.
ULANO AMBERLITH . . .a companion to Rubylith serves as a color separation mecium used as the master on camera copy board to secure negatives or positives. A wide variety of Ulan films--
in rolls and sheets--is readily available
(Designed
FOR YOUR PARTICULAR NEEDS
Ulano offers the most versatile line of hand-cut
masking films, including:
.0075--RUBYLITH 75 DR* .005--RUBYLITH 5DRt
.005--AMBERLITH 5DAt
Where exact register assures a critical importance, you will find these new, thick, polyesmer based films the positive answer. *Available in sheets only, cut to your specifications tAvailable in rolls and sheets

Now carefully peel off the film as outlined leaving acompleted mask, positive or negative, that corresponds exactly to the desired pattern.
"Ulano"-"Ilubylith"-"Amberlith" are registered trade marks of the Ulano Companies.

WRITE TODAY on your letterhead for free
special sample kit, 174s

ulanc>
Electronics April 15, 1968

610 DEAN STREET, BROOKLYN, N.Y. 11238
In Europe: ULANO A.G., untere, Heslibachstrasse No. 22, Kusnacht, Zurich, Switzerland

Circle 197 on reader service card

197

Sea duty. Navy will post this electric keypunch setup being built by Taller and Cooper to sub and destroyer fleet.

big inch!

New BIG INCH - Synchronous Integrating Motors
Like peas in a pod but available in different speeds and voltage ratings. The HSI Series 33000 is approximately 1" x 1" small, yet unmatched for its size in precision, power, efficiency and low cost. It's the ideal drive for elapsed time indicators, stop cloc ks, pulsers, interrupters ,.timing devices, chart drives -- and many other applications. Outstanding features include...
Fast Start/Stop: From dead stop to full speed in 1/100 sec., stops instantly without coast.
High Torque: Higher than many motors twice its size. Low Wattage: Only 1watt input at rated voltages. Sealed Gears: Permanently lubricated for long life. Low Cost: Tooled for mass production.
Available in speeds of 360, 300, 60 and 3.6 RPM, 20V and 115V 60Hz.
SEND FOR NEW BULLETIN NO. 33-1

HAYDON SWITCH 86 INSTRUMENT, INC.
Where Optimum Performance is Standard
1500 Meriden Road, Waterbury, Conn. 06720 / Area Code (203) 756-7441

198

Circle 198 on reader service card

can be reused after the data is discarded.
Newcomers. The original model 1101 data recorder, first produced in 1965, has since been joined by a line of machines that provide: pooling of data from several keyboards onto one tape; data communications capability; and input from paper tape, punched cards, or a typewriter keyboard. Other models put longer records at higher density on nine tracks for compatibility with the newest computers. The machines are sold directly by the Mohawk Co. and, under aprivate-label arrangement, by National Cash Register.
The Mohawk machines, although pioneers, weren't the first of their kind. During the early 1950's Univac (then part of Remington Rand Inc.) marketed the Unityper, which recorded individual characters from a typewriter at low density on a metallic tape. Mechanical difficulties with the incremental drive and the difficulty of verifying the recorded data and correcting errors led Univac to withdraw the machine from the market.
Bigger buffers. Mohawk has recently been joined by Honeywell Inc., which introduced its Keytape machine this January. Keytape is the functional equivalent of the data recorder, but Honeywell claims a faster speed and the capacity to record at higher densities on seventrack tape. Honeywell's machine is essentially a standard tape drive like those used on computers, winding tape from reel to reel. The company says this is superior to Mohawk's technique in which the tape is unreeled as it is written, dumped loosely into a bin, and wound at the end of the job.
Both Mohawk and Honeywell depend on the 80-character record
length, just as punched cards do.
Circle 199 on reader service card-->-

íï
Sy vanians do as they're told.

Our living depends on it. We turn out 50 million customfabricated parts aday. To exact specifications. Including precision stamping of hightolerance, miniature metal shapes. Precision molding of intricate plastics parts. Precision forming of wire for critical electronics. Combining metals, plastics and wire into precision-built assemblies. We live by our accuracy. After all, if we don't do what we're told, you

may not tell us anymore. We've been doing it for over 17
years. On transistor leads, computer memory core frames, connectors, oen caps, aerosol spray tips, razor blade dispensers, integrated circuit frames.You name it.
We've got nine plants, the most advanced equipment, and the best engineers and die makers around to do it.
And we'll even help you design the part. Then we'll build the dies, produce the parts, and do the assembly. Exactly as we're told.

That means you get the parts you want, the way you want them, when you want them--probably at less cost than you could do it for yourself.
So the next time you need acustom fabricated part, call aSylvanian and tell him what to do.
Sylvania Metals &Chemicals, Parts Division, Warren, Pa. 16365.
CUSTOM PARTS BY
SYLVAN IA
GENERAL TELEPHONE &ELECTRONICS

EPETERFORMANCE
REQUIREMENTS
le USING HAIVIIeN PRECISION STRIP AND FOIL
The most critical performance iuquirements for thin metals can be met by Hamilton strip and foil. Regardless of these requirements of your thin metal application-- strength, hardness, surface finish, optimum magnetic permeability or dimensional accuracy--you can get them all from Hamilton Precision Metals.
Every lot of Hamilton strip and foil is produced under rigid control of mechanical properties through alloy analysis, annealing and heat-treating; the closest dimensional control by means of X-Ray and Beta-Ray gages; superior surface finish through the use of diamond lapped work rolls and process cleanliness.
This same technical "know-how" goes into the processing of every one of our 7 proprietary metals, 12 pure metals and 112 commercial alloys rolled in thicknesses from 0.060" down to 0.000070" in widths up to 12" and continuous coils to 1000 lbs. Write, wire or phone giving us the material you desire and the properties you need. We'll tell you how fast we can get it to you--in quantity! Or, write for our latest catalog containing our capabilities and engineering data on all our materials.

However, the machines can extend the record simply by increasing the size of the buffer memory. Honeywell intends to compete with Mohawk in replacing keypunches.
Another one. Sangamo Electric Co., of Springfield, Ill., is preparing aunit similar to the Mohawk and Honeywell machines for introduction later this spring along with related equipment for data communication applications. Sangamo recently acquired a California outfit--a move that attests to its height-
ened interest in data recording and related activities.
IV. Communications link
A magnetic recording device similar in several respects to the data recorder and the Keytape was introduced last fall by a New York firm, the Communitype Corp. The machine transcribes data from a typewriter keyboard onto magnetic tape in asmall cartridge and simultaneously makes a hard copy on the typewriter. If the typist makes an error, the typewriter and the tape can be back-spaced to correct it. The recorded data can be speedily transmitted over a telephone line, re-recorded on computer-compatible tape in a separate converting machine, or automatically recopied on the typewriter. An optional addressable memory unit, actually another piece of tape in a small desk-top housing, stores frequently used information; the data can be transcribed onto the cartridge tape without being repeatedly entered from the keyboard.
The Communitype device is similar to the others in that it makes card punching unnecessary. But it is primarily a data communica-

HAMILTON PRECISION METALS

Division of Hamilton Watch Company, Lancaster, Pa. 17604 Telephone 717-394-7161 TWX 717-560-4417

200

Circle 200 on reader service card

No toy. Taller and Cooper produces a portable unit that prints characters and makes punches just like IBM gear.
Electronics April 15, 1968

You simplify your RG Cable problems if you know in connector at. (That's another thing -- are you sure your

advance everytning you should--like bend radius, VSWR, power handling capability, phase temperature, coefficients,

present connectors will give you the assembly characteristics you're looking for?) Our current stock is the largest and

dimensional stability and transmission unbalance, lust to most vareo in the business. Cur Weekly Inventory Report

begin with. But if you're shy an answer or twc, or you is famous -- and we'll be glad to put you on the mailing list.

aren't sure of all the questions you should be asking, give Our capability for specials is :endless. And our knowledge

our Engineering Service Department acall. Over the years we've developed astaff that knows Cl

and experience are at your disposal. So get in touch with Times on your RG questions.

little more, digs alittle deeper , asd has the answers to every Tnat way you'll know us--as well os what we know.

RG cable question they hove ever been asked. We've For our lates cable catalog, tech memos and stock

ith RG Cable, made more than 1000 different types of flexible and RG
Cable. We've accomplished more econom ica ltrade-offs than you can shake

list, write- Times Wire & Cable/a division of The International Silver Company, Wallingford, Conn or phone (203) 269-3381 .

it isn't who you know,

it's what you know.

Ross Strait, Jr. B.A., Physics

Jack Arbuthlo -t IS., Electrical Engireering

Russ Edmond B.S. and M.S., Mechanical Engineering

Dave Peterson B.S., Mathematics

Al Kushner B.S.,
Mechanical Engineering
M.S., Electrical Engineering

Fred Baughman Ph.D.,
Chemical Engineering
Newell McDonald / B.S., Mechan .cal Engineering

TIMES
WIRE f!
Circle 201 on reader service card

... some machines read only single lines...

...with one of HYSOL's seven printed circuit coatings by Spray, Dip or Brush

HYSOL, the most experienced producer of printed circuit coatings, offers the widest range of coatings for commercial and military uses. HYSOL epoxy coatings PC12-007-M, PC16-M, PC23-M and PC26-M meet the rigid MIL-I-46058B requirements, and urethane coating PC22 meets NASA MSFC-SPEC-393 specification requirements. Testing in a complete electronic testing laboratory insures precise quality control. HYSOL epoxy and urethane coatings are in use protecting circuits on military and commercial jet aircraft, aerospace vehicles, control, communication and EDP equipment. All HYSOL coatings are proven fungus resistant (MIL-E-5272) and all are transparent. Write, wire or phone HYSOL, Dept. EM-48, Olean, New York 14760, for application engineering assistance. Ask for Printed Circuit literature.

H y scaL HYSOL DIVISION

THE DEXTER CORPORATION

See us ut the Show

Booth No 64

202 Circle 202 on reader service card

tion device. Since its tape isn't computer-compatible, there must be an extra operation--over atelephone line or locally--to put the data into a form directly acceptable to acomputer.
Cousin. A related device, primarily for communications but also applicable to computer inputs, is Digital Devices Inc.'s new buffer (see page 218), which uses amagnetostrictive delay line instead of apiece of magnetic tape as atemporary storage.
Univac recently developed anew kind of unit record that has many of the advantages of punched cards and few of the disadvantages [Electronics, March 18, p. 48]. It's a plastic card, able to store up to 100 times as much data, that's recorded magnetically like astandard punched card. The data can be erased and the card reused indefinitely. And the cards can be individually handled.
V. Look-see
Other potential threats to punched cards are optical character readers and magnetic-ink character readers. The latter form of recording is already used by most commercial banks for checks.
Optical character readers are made by several companies, including the Optical Scanning Corp., National Cash Register, Farrington Electronics Inc., IBM, the Control Data Corp., Recognition Equipment Inc., and the Philco-Ford Corp. Some machines read only single lines, while others can assimulate whole pages. Some read only stylized type fonts, other almost anything. "Most of the machines are quite expensive from a systems point of view," says Myron Angier, director of Honeywell's Special Products division, home of the Keytape machine. "They will eventually take over the unit record function that punched cards now handle, but we don't expect much competition from them for quite some time." Honeywell doesn't now make an optical character reader.
On display. Crt displays with associated light pens or keyboards offer another possible alternative to
Electronics IApril 15, 1968

PNP

GERMANIUM

M11, 111-)M

TO-68

DOUBLE ENDED VERSION

POWER

Solitron offers 65 Amp Germanium Power Transistors in a TO-68 case or double-ended version. Both packages provide heavier leads than the TO-36 case for more efficient use of power. These high current devices are identified as the SDT 1800 and SDT 1900 Series, and include the JEDEC registered 2N2730-35 Series. Typical uses include motor speed controls, computer printers, welder-control circuits, inverters, converters, regulators and many other high current power supply and control applications.
A wide variety of other PNP Germanium Power Transistors, with current ratings up to 25 Amps, are available in aTO-3 case. Also, many general
purpose and JAN qualified devices.

TRANSISTORS EOM
FROM olitron

Type Number TO-68
MHT1808 MHT1809 MHT1810 2N 2730
N 2731 2N 2732 SDT1860 SDT1861 .S011862

Type Number OCUB_E-ENDED VERSION
MHT1908 MHT1909 MHT1910 2N 2733 2N 2734 2N 2735 SDT1960 SDT1961 SDT1962

Breakdov n Volt.Ig.

V, ii
80V 60V 40V 80V 60V 40V 80V 60V 40v

V.
60V 45V 30V 60V 45V 30V 60V 45V

15 m r, ',50A 15 mir 50A 15 mer 50A 15 mir 65A 15 mir -, 65A 15 m r_,65A 20 mr 765A 20 mn ;65,\ nmin '6', \

SAT Vo lago . Max Rated I

Vfit
125V 1.25V 1.25V 1.25V 1.25V 1.25V 1.25V 125V 125V

V
45V A5V 45V 45V 45V 45V .30V 30V 3CV

SOLITRON HAS COMPLETE FACILITIES FOR ALL TYPES OF ENVIRONMENTAL AND BURN-IN QUALIFICATIC NS TESTING.

Dial 1-800-327-3243 for a "No Charge" telephorw call and further information

%I elee yelet

oJeim/di

lein4 (.90e4011/

olltron DEVICES, INC.

1177 BLUE HERON BLVD RIVIERA BEACH, FLA./ TWX: (510) 952 6676

Electronics April 15, 1968

Circle 203 on reader service card

203

Lapp Entrance Insulators

Op art. Optical Scanning's character reader can read single-line forms at aspeed of 600 per minute.

The sizes vary... But our skills are always large.
Lapp skill in designing and building entrance insulators goes back over 43 years. We're big on design knowledge, ingenuity and ability to deliver the job ...right to your requirements.
Standard designs, or special types, Lapp can produce entrance insulators for almost every electrical and mechanical requirement. Save your company time, money and searching ... call in Lapp when your projects require entrance insulators, or antenna, or tower insulators.
Put Lapp skills to work for you ... from design to delivery. Lapp Insulator Co., Inc., LeRoy, N. Y.
Lapp

punched cards. However, they too cost much more than conventional equipment, and hard copy isn't automatically available from adisplay. The principal advantage of crt's is their ability to provide on-
line real-time access to acomputer --a capacity fundamentally beyond punched-card systems.
Further development work on OCR'S and crt's will make them more and more attractive as possible replacements for punchedcard equipment. Meanwhile, another, less obvious alternative is a "keydisk" setup. Perhaps a machine could be built to enter data directly through akeyboard onto a portable disk pack. However, no one could use enough of this system's potential to justify its high cost. For one thing, a single disk pack holds about as much data as areel of tape but is much more expensive. Its most effective application would probably be storing data from several keyboards run-
ning in parallel. Its random-access capability would separate the data from the various keyboards.
A way to take advantage of this pooling capability isn't evident now. Both Honeywell and Mohawk offer pooling devices as accessories to their machines, but the pooling operation is separate from the keyboard operation. First, the individual tapes are made, then several of them are pooled onto asingle reel. Also, despite the recent rapid growth of the disk-pack industry, disk packs themselves are still a very small part of the total industry picture. They will remain so for some time, partly because of the vast prior installation of magnetic tapes as a bulk storage medium. Also, disk packs sell for $490, as against $25 to $35 areel for magnetic tape.

204

Circle 204 on reader service card

Electronics lApril 15, 1968

"0"-RING MOISTURE SEAL

MECHANICAL STOPS (SLIP CLUTCH IDLER)

35-TURN ADJUSTMENT
SCREW
GOLD PLATED NICKEL PINS

SUREGARD TERMINATIONS-- BOTH ENDS OF ELEMENT
DIRECT-TO-ELEMENT PIN

MISSING: a few connections GAINED: new reliability at abargain price

Design omissions can be as important as additions in product performance. An inside look at the new DAYSTROM Squaretrim® 554 Series pot, for example, shows that intermediate pin connections have been eliminated. Two of the weldable base pins are affixed directly to the resistance element. The center pin pivots directly against the rotating tap assembly. Result ?A simplified design which also lowers your cost. Made in accordance with MIL-R-27208, these half-inch units are rated for afull watt in still air at 70°C. Sealed models have passed Weston's 100% immersion test. Now thrifty-minded military, industrial or commercial users can have Squaretrim quality features at a bargain price. Write today for complete data and evaluation samples of our 550-555 Series potentiometers.

· Patented "wire in the groove" construction
· 10 ohm to 50K resistance range
· ±5% standard tolerance
· --55 °C to +150 °C temperature range
· Choice of pins, flexible leads, and screw configurations
· Choice of sealed and unsealed models
· Prced competitively

DAYSTROM potentiometers are another product of:
Weston Components Division, Weston-Archbald, Archbald, Pennsylvania 18403, a Schlumberger company
WEST ON® prime source for precision ...since 1888

Electronics April 15, 1968

Circle 205 on reader service card

205

New Components Review

D-c torque motor 1700-040 develops 15 oz in. of peak torque with 65 w input. Frameless configuration allows the motor armature to be mounted directly to the driven load shaft. The motor is axially thin (0.40 in.) and o-d is 1.69 in. Rotor inertia is 0.007 oz/in./sec 2 and no load speed is 4500 rpm. Magnetic Technology Inc., 21001 Kittridge St., Canoga
Park, Calif. 91303. [341]

High power baluns and impedance matching transformers are for applications in matching unbalanced transmitter outputs to balanced
antennas or transmission lines. Models are available in 100, 500, and 1,000-w ratings for the 2-to 30-Mhz range. Model PB500 is
rated at 500 w average power at maximum frequency. Kappa Networks Inc., 165 Roosevelt Ave., Carteret, N.J. 07008. [342]

Sensitive relays designated RBM

MS 40 are spdt units that mea-

sure 11/8 x 11/8 x

in. They

feature long life and low cost.

Contact ratings are 2 amps non-

inductive at 28 y d-c and coil

power range is 0.050 to 1.0 w.

The armature is common to the

frame with 4-40 mounting and

solder terminals. Controls Division,

Essex Wire Corp., 131 Godfrey

St., Logansport, Ind. [343]

Miniature switch E33-90H features contoured form on integral hinged lever actuator for cans or slide actuation from either direction. It is rated 10 amps, 1/2 h-p
125/250 y a-c, but can also be furnished in 5 amp and 15 amp
versions. Net cost (2,000 pieces) is $0.437 each. Cherry Electrical Products Corp., 1650 Old Deerfield Rd., Highland Park, Ill. 60035. [344]

Miniature bobbin wirewound resistor WWP-225 is rated at 1/8 w in a temperature range from --55° to +125°C, derating to zero at 145 °C. It stands 0.312 in. hign by 0.250 in. diameter. It is avail-
able in tolerances from 0.05% to 1% within a resistance range of 0.1 ohm to 515 kilohms. Temperature coefficient is ±20 ppm/°C. Dale Electronics Inc., Box 609, Columbus, Neb. [345]

Miniature reed switch MR338 is a nitrogen gas-filled, center-gap, spst unit suited to permanent magnet or electromagnet operation. Rhodium contacts are rated 10 w d-c resistive, 12 v-a a-c resistive, and 0.003 amp. Minimum voltage breakdown is 1,500
d-c. Price is $1.24 in quantities of 100 pieces. Gordos Corp., 250 Glenwood Ave., Bloomfield, N.J.
07003. [346]

High deflection sensitivity and high brightness are features of the WX30764 electrostatically focused crt. The 51 2 x 41/2-in.
tube, with a center line width of 0.015 in. (15 mil), is for oscillographic and data display applications. It has an aluminized, rectangular screen, weighs 31/4 lbs, and mounts in any position. Westinghouse Electronic Tube Division, Elmira, N.Y. 14902. [347]

Resistor series HA is usable from d-c to 100 Mhz and above, with absolute tolerances to 0.001%, shelf stability of 5 ppm/yr. Tem-
perature coefficients are 0 ±-1 ppm/°C (absolute), 0.5 ppm/ °C (tracking) and 0.25 ppm/ °C (matching). Price, in 100 lots, is
$5.70 each for the 0.01% HA412 units. Vishay Resistor Products, 63 Lincoln Highway, Malvern, Pa.
19355. [348]

New components
Cable assemblies get the thin look

First connector specifically designed for flat cable with 50-mil centers, features environmental shielding

Only about 4% of the wiring going into new aircraft and missile airframes is flat conductor cable. But according to industry estimates,
this figure could soar to about 85% in 10 years if the right hardware is developed. Now Microdot Inc. believes it has come up with some of

that hardware.
According to Wendell Jacob, connector and cable products manager at Microdot, "Up till now, the only connectors available were warmedover versions of some other kind of connector such as printed-circuit types, and they're for 100- or 75-mil

cable. In our Mark 220 connector we've developed the first unit for 50-mil centers."
Microdot first got interested in
designing such a device after the firm was approached by a major aerospace manufacturer with its requirements for flat conductor-cable terminations. Then the McDonnell Douglas Corp. verified the need for the unit after performing a costweight study on aerospace cables and connectors for NASA. Finally, after Microdot had its in-house development program under way, it learned that the Army's Picatinny Arsenal was preparing anew military specification, now circulating

206

Electronics IApril 15, 1968

General purpose industrial relay style L is available with contact arrangements from spdt to 4 pdt and ratings from 5 to 10 amps. Contact resistance is rated at 0.05 ohm max. Ambient temperature range is --55 ° to +85 °C. Dielectric strength is 1,250 rms. Predicted mechanical life is 1 million operations. Price Electric Corp., E. Church & 2nd Sts., Frederick, Md. 21701. [349]

Radiator heat sinks feature a patented insert that fits on the heat sink case and makes a firm pressure contact to the rim, top and over 60°.4 of the side surface This assures a thermal conduction coefficient of 2 w/ °C from transistor case to heat sink. The HA05R fits TO-5 cases; the HAl8R, TO-18 cases. Horex Electronics Inc., 1729 21st St., Santa Monica, Calif. 90404. [350]

Power resistors series FP and XFP are for p-c board applications. They can be inserted in 0.050 or 0.070 diameter holes, and are 0.020 thick x 0.035 or 0.054 wide. Center-to-center distance of prongs on the terminals is variable from 0.5 to 2.5 in Resistance range is from 0.2 ohm per in. to 1,000 ohms per in. Lectrohm Inc., 5560 Northwest Highway, Chicago, 60630. [351]

Glass-encased Neptune ceramic capacitors offer 10 to 10,000 pf in a case size of 0.250 x 0.095 in. The ceramic slug is both brazed to the lead-cap and encapsulated in an inert-gas atmosphere, thus preventing contamination. Units are available with a temperature coefficient of 30 ppm/ °C. San Fernando Electric Mfg. Co., 1509 1st St., San Fernando, Calif. 91341. [352]

Ultraminiature tubular and flat Thinfilm metalized polycarbonate dielectric capacitors series 396397 are available in 0.01 to 104. They operate within the range of --55" to +125" C without voltage tierating. Dissipation factor at +25" is less than 0.5 0'4 at 1,000 hz. Leads are axially oriented. Gudeman Division, Guiton Industries Inc., 340 W. Huron St., Chicago 60610. [353]

Ten-turn precision wirewound Pix-
iepot has plastic shafts up to 1.8 in. long, minimum torque to 2.0
oz-in. Model 3253 has a resistance tolerance of 2-'5% over a standard range of 100 ohms to 100 kilohms. Linearity is ±0.25°,4 and resolution for a 1-kilohm pot is typically 0.022. Duncan Electronics Div. of Systron-Donner
Corp., 2865 Fairview Rd., Costa Mesa, Calif. 92626. [354]

Wirewound trimmer style RI-24 type 700 meets environmental re-
quirements of MIL-R-27208. It features positive clutch action that insures against damage to contact wiper and drive mechanism. It is available over a resist-
ance range of 10 to 50,000 ohms, ±5% tolerance, and is rated 3 4 w at 85 °C. IRC Inc, 401 N. Broad St., Philadelphia, Pa. 19108. [355]

Plated-through-hole p-c boards facilitate mock-up circuitry. Four configurations available accept 14pin dual in-line IC's, TO-5 packages, and discrete components. Extra holes are provided in the land areas for jumper wires to effect circuit hook-up. Circuit changes may thus be made easily and quickly. Midwest Circuits Inc., 1111 E. Excelsior Blvd., Hopkins, Minn. 55343 [356]

for industry comments, covering flat
conductor cable connectors.
At the show. User requirements for flat cable connectors were outlined at a meeting of the Institute of Printed Circuits in New York last month. One user at the meeting
says that N'hile Microdot and the International Telephone & Tele-
graph Corp.'s Cannon Electric Division had connectors to show,
neither meets all the requirements the users want.
However, he did say Microdot
N'as the first company with enough courage to come up with a new
connector for flat cable, and it came pretty close to the requirements

the users gave.
According to Jacob, the users aren't sure exactly what they want.
He also attended the meeting and says the users are not in agreement, especially in the area of electromagnetic capability, so Microdot will try to incorporate environ-
mental sealing inside the shell if it does not interfere with reliability. The users asked for this, along with a different kind of coupling
mechanism--jack screw or snap lock coupler.
Jacob says Picatinny personnel indicated the Microdot design philosophy was sound, assured Micro-
dot officials there would be acon-

Housing. Connector shells are impact-extruded aluminum and are gold-plated--a requirement of the aerospace industry.

Electronics ¡April 15, 1968

207

Bulova ovens are the smallest going
--but they do a big job!
Simply stated, the Bulova BDX series is the smallest and most versatile in the miniature oven field!
Now, for the details. External dimensions are just 1.5" x1.19" x.46 (or up to .9375", for larger models). Yet, the BDX can hold 1to 6tubular devices such as diodes, capacitors or resistors, up to .25" in diameter and length.
Controller is an RFI-filtered snapaction thermostat, meeting MIL-I-6181B. You get the BDX with your components installed and encapsulated in fluoro-carbon blown polyurethane foam insulation and hermetically-sealed. Result: aunit with minimal thermal leak that will withstand the most severe shock and vibration specifications.
The BDX is available with stud mounting, printed circuit board mounting, flange mounting or captive nut. Temperature settings from 50°C to 100°C are available, with arange of operating voltages from 6.3 to 117 VAC or DC. Temperature stabilities are as fine as .5°C over a--55 °Cto 90 °C with apower drain as low as 5watts.
This is just one of acomplete line of Bulova ovens, including bi-metal thermostat, transistat, solid state switched mercury, and AC or DC proportional controls. For more information, write today to Dept. E-28,
Try Bulova First!
FREQUENCY CONTROL PRODUCTS
ELECTRONICS DIVISION OF BULOVA WATCH COMPANY, INC.
61-20 WOODSIDE AVENUE WOODSIDE, N.Y. 11377, (212) DE 5-6000

... connector designed
without sponsorship...
tinuing market and substantiated that Microdot was the first firm they knew to be designing a connector strictly for flat cable. With this reassurance, Microdot proceeded with the Mark 220, without waiting for sponsorship to underwrite the development, which, says Microdoes John Redwine, is usually the way new connector developments are launched.
Same as before. The Mark 220 will incorporate the twist pin employed in all Microdot connectors rather than screw-machine-produced pins. Microdot is under license to the New Twist Corp. for this concept, in which the pin is made of 10 strands of 48-gauge to 50-gauge wire, and has an outside diameter of 0.0315 inch ;the socket that accepts the pin has an inside diameter of 0.028 inch, so that the wider pin twists and elongates as it enters the socket, giving more positive electrical contact than screw-machine-made pins, Redwine says.
In the 220, pins and sockets are joined to their respective flat cable conductors in an insulator module made of diallyl phthalate. Redwine says the material was chosen because of its good temperature characteristics and good compressive strength. Microdot inserts the pins and sockets in their respective molded insulator modules, and the customer will join each half of the connector to the flat cable.
The mating call. Jacob points out that when the Mark 220 design was initiated, the company wanted to fashion it so that the entire flat cable could be mated to the insulator module--containing pins or sockets--in an automatic process independent of the type of connector shell that would ultimately house the mated pair. In this manner, he believes, the insulator module-tocable termination can be done in a 30-second welding of pin or socket module to the wires in the cable. With round cables, as much as 10 to 15 minutes can be consumed in soldering individual wires to the connector. This production speedup will be as persuasive as potential weight savings in contributing to

ECCOSORB®
COMPLETELY REVISED
Six page folder in color describes and gives performance data on the complete line of Eccosorle Microwave Absorbers for Free Space and Wave-guide.
Circle 512 on readers service card
ECCOSORB°
ANECHOIC CHAMBERS NEW DESIGN 7
Illustrated folder gives details on anechoic and shielding performance of several new chambers used for antenna pattern, radar cross section, VSWR and RF compatibility measurements.
Circle 513 on readers service card
ECCOSHIELD°
RF SHIELDING MATERIALS
Brand new six-page folder in color describes a complete line of Eccoshield products to combat RFI conductive plastic sheet and gaskets, adhesives, coatings, caulking compounds, metallic foil--the works.
Circle 514 on readers service card
Emerson &Coming, Inc.
CANTON, MASS. GARDENA, CALIF. NORTHBROOK, ILL.
Sales Offices in Principal Cities EMERSON & CUMINS EUROPE N.V., Oevel, Belgium

208

Circle 208 on reader service card

Circle 209 on reader service card-->-

The first $1500 digital muftimeter
that sells for $895.

Tne new trio/lab Digital Multimeter Model 501 is the first battery-portable, automatic ranging and polarity, full-capability DMM ever offered -- at any price.
State-of-the-art IC techniques, high sampling speeds, rugged construction, rechargeable ni -cad batteries ... perfect for both field artd bench use. This unique instrument is simplicity itself -- just push a function button and read.
Trio Laboratories, Inc., 80 Dupont Street, Plainview, L. I., N. Y. 11803.
Tel: 516-681-0400, TWX: 510-221-1861.

Ranges: Voltage -- DC/AC: 1mv to 1KV in 4 ranges Current -- DC/AC: 1 ga to 1 A in 4 ranges Resistance -- 1Ohm to 1Megohm in 4 ranges
Accuracy: DC Volts, DC ma, Ohms, +0.1% of reading + 1 digit AC Volts, AC ma, +0.5% of reading + 1digit
Over-ranging: 100% with no loss of accuracy
Input Z: 10 Megohms
Mechanical: 4%" x10 1/2"x10 3 /4 "deep; 12 lbs.

/
ORIGINAL CONCEPTS IN INSTRUMENTATION

Wire brim The POI Industry on li's
Ear!

tki1 /44%.44e..-
i`NOW,il 10-Turn, Precision Rewound
p/x/Epor M

FOR AS LOW AS T

PA1 PEND

$

31.97ACH

That's right! The Duncan Model 3253 "PIXIEPOT" potentiometer is yours for as low as $3.97 each in production quantities and only $5.95 each for 1-24 units. Match the following "PIXIEPOT" features with any other similar pot on the market.

·Length: ONLY 3 / 4 ·Diameter: ONLY 7A3 "

Dee m**,

·Linearity: '0.25% ·Resistance Range: 100 ohms to 100K ohms

04111IA

·Power Rating: 2 watts @ -r 20 C ·Temperature Range: --25 C to 85 C

SHOWN 0110M SIZE

·Resolution: Better than ANY wirewound pot TWICE its size! ·Slotted Stainless Steel Shaft

A Duncan "PIXIEPOT" can save you dollars on your instrument and system requirements. If you want to know just how many, call or write us today. The full story on the "PIXIEPOT" will be in the mail to you within 24 hours.

210

.trifr

41Ele

DUNCAN electronics, inc.

A DIVISION OF SYSTRON-DONNER CORPORATION
2865 FAIRVIEW ROAD. COSTA MESA, CALIFORNIA 92626 Phone: (714) 545.8261

Ciicle 210 on reader service card

the predicted boom in flat conductor cable, Jacob adds.
Other uses. Microdot is considering acommercial/industrial version of the connector for such hardware applications as computers, but officials say they've just begun to study the most suitable material for the housing.
The connector is made in sizes from one inch to three inches wide, in increments of one-half inch, and accommodates from one to three stacked cables.
Specifications for the industrial version have not been fully worked out, Jacob says, because Microdot wants to encourage the industry to spell out its needs. Prototype devices for feasibility or research and engineering evaluation can be delivered in 8to 10 weeks. Prices have not been firmly fixed, but Redwine estimates the devices will cost about $1 per mated contact (one pin in one socket) plus housing costs--or about $60 for amated pair of 34-conductor units.
Microdot Inc., 220 Pasadena Ave., South Pasadena, Calif. 91030 [357]
New components
Taking complexity out of pin positions
Automatic wire wrapping boosted by simpler, less costly connection method
Despite the superiority of automatic
wire wrapping over hand wiring, not everyone has climbed on the bandwagon. Although higher initial cost has kept some would-be users away, complex pin positioning has caused others to back off. Tolerances are so tight that the slightest error can lead to costly production delays.
Now, however, Litton Industries' Winchester Electronics division has developed what it calls AccurFrame packaging--a far simpler and less costly system of putting pins on a plate than conventional methods.
Circle 211 on reader service card-->-

417-the lightweight recorder for heavy duty field use

nthe field or :r atest raige, the -uggec, portable Lockieed 417 is -ig1T-.at hone. Just as it is whereever :I-ere's data to record ..ir tF e air, on the seas and unie -:In, n plarls cr labs or out in the w
Neigis 3nly 28 IDS. with jatte-y -- 50 Its. _alder ary comparable r?.D3':-.er. Vleasu -es 14"x15"x6" ..rridEr aplaie seat). Purs on 11)1220v PC/DC 3r i-rernal batteq. Power cortst..mption as low as 10w.
Accuracy matches la -ge rac. nac in 3S. Has phaselock sIerv3fz-r precise speed control. Re...-.crds oi 7 :Flannels, IF G corn3a-.4313.
Tegl-eJ as ¡owes $7,C0C.

LOCKHEED

ExclLsive low-riass differential capstan drive g ves precision recording even in roLgh'ield ccndtions. Smplif ed, nairtenancefree mer_hanism vic -ks under vibration and in any pcs tipn.
F-equen:y respoise: 100 c d rect, 10 kc Ffe.
Send for our catalag co -taining fLIlÉetai on :he 41 7 --one ol a famili af 3recisior data recorde -s for lane, c.s.een, air an Ispa ceap iiication. Wr te B3yd Anig -t, Dept. E-4H, I.)ckheed Elect -onics Company, Edison, New JErSey.
Questicns about lela rec ardirg? Let's discLss. Celli 2C 1: 757-1600.

Lockheec Eleclronic5 Conpany. A Division of Lockheec Aircraft Corpora:ion

;:i:4;ter e

· °

A new way to dependable,
compact, low-cost, digital
COUNT AND CONTROL

DURANT 49600 UNISYSTEM
The answer to a need for fast, accurate count or control in most industries -- machine tool, textile, wire, boxboard, electrical, paper, lumber, printing, food, chemical, and other industries. Controls fluid metering, batching, testing, cutting, packaging; counts cartons, coil turns, lineal lengths, and units per bundle. Exceptionally dependable; count always retained in case of power failure.
Compact size permits space-saving desk mount or panel mounting. Choose 2, 3 or 4-digit predetermining and count levels. Also available in Splash and Dustproof models. Speed ranges from 0 to 30 cps (1800 cpm). Large, easy-to-read visual display
Easy push-button setting of predetermined number -- preset value always retained, always visible. Instant electric reset from panel front, remote reset, or automatic cycle repeat. Setup and connecting is easy, too... rear panel terminals allow 49600 to be readily applied to avariety of operating functions.
See it demonstrated at your desk! Write for specifications.

I=1

f=1 NJ

itAlitIFACTUR NG COMPANY 1 622 North Cass Street
MILWAUKEE, WISCONSIN
In Europe: Durant (Europa) N.V. Barneveld, Netherlands
Visit Booth #362 at Design Engineering Show

6455

212

Circle 212 on reader service card

James Muller, Winchester's sales manager, says the AccurFrame method costs from 1to 3cents less per contact than other techniques.
Consisting of the company's i-rw series edge-board connectors, custom-designed positioning and wiring frame tools, and nw series contact-replacement kits, AccurFrame is merely an extension of the connector-molding technology. Conventional methods use multiple punching of close center holes in the plate-type assemblies.
Making the fit. With AccurFrame, two alignment holes, one round and one square, are molded into the base of the mv connector blocks. These fit over accurately-positioned guide pins, also one round and one square, on amaster alignment tool. Each pin is independently measured from reference points and is within 0.001 inch true position. With the connectors in position, a frame is placed over the assembly and attached by machine screws to the connectors.
If the terminal posts become damaged during assembly or production, they can be replaced with the simple hand tools provided in the contact-replacement kit.
The uw connectors are precision molded of diallyl phthalate. The contacts are retained in the connector block by a 90° twist-- resulting in a diagonal placement. Conventional methods of locking in the contacts--staking and dimpling--tend to weaken the contacts and lead to ahigh degree of breakage.
The price of AccurFrame is about 5.5 cents per contact, depending on the size and the number of frames produced.
Winchester Electronics, Main St. and Hillside Ave., Oakville, Conn. 06779 [358]
Electronics IApril 15, 1968

How to Use E-CELLTM Timing and Integrating Components
The Bissett-Berman Components Division engineering staff answers four basic questions often asked about E-CELL* devices

(
d-t1
77a1E-4

1. What is an E-CELL device?
An E-CELL device is a new kind of circuit element that looks like adiscrete electronic component but does the work of a complex assembly. Its main functional part is acenter electrode, which is surrounded by an electrolyte; the metallic container also serves as the second electrode. In terms of its physical operation, an E-CELL unit is a reversible micro-coulometer, i.e., it converts the current-time integral of an electrical function into an equivalent mass integral (or the converse operation) up to a maximum of several thousand microampere-hours. Exactly
t one atom is transferred for each elec-
tron impressed on the E-CELL unit. Power drain is normally in the microwatt region. The mass integral can be read out at a known current, the time to read it out being proportional to the original integral. When amass is given
as part of the initial condition, this same process generates a precise time interval.
2. What does an E-CELL device do?
For timing applications aconstant current is applied to a pre-charged E-CELL unit. The selected time delay is determined by a combination of the E-CELL type and the specific constant current being used.The range of timing is from seconds to months. The output voltage swing that occurs when the mass has been completely transferred is normally used as a bias transition with semiconductor devices.
For integration applications, an uncharged E-CELL unit accepts d-c, periodic, or random inputs in any waveshape and stores these as the mass equivalent of a current-time integral. Readout is handled in essentially the same manner that the timing function
is handled for a pre-charged E-CELL unit, i.e. the measured time required

to reach the point of the abrupt voltage swing, multiplied by the readout current, will be the accumulated charge integral. This could represent the total "count" of aseries of events analogous to the input pulses.
3 When should Iconsider using an E-CELL device?
The scope of applications is as broad as timing and counting functions themselves. New uses are continually being devised. Here are two prime applications areas:
Control: You can use E-CELL devices in circuits for timing, gating, starting, stopping, delaying, relaying, monitoring, actuating, sequencing, measuring --wherever the control condition can be represented by an electronic signal.
Information Handling: You can use E-CELL devices in circuits for data capture, totaling and subtotaling time periods or discrete events, elapsed time logging, running time monitoring, outof-limits logging, maintenance status reporting, real-time analog computing --wherever the input data can be represented by an electronic signal. Readout can be formatted as either analog or digital data.
4. What are some present production uses of E-CELL devices?
Fuzing and arming; battery charging; cardiac output integration; sonobuoy scuttling; high-power tube protection; engine maintenance scheduling; warrantee monitoring; time delay relays; transistor aging racks; program timer; r-f level monitoring.
"Patents applied for.

Analog of physical event
process
M .- 6,fNoc,ç -55 °C. to 7/°C.

El I55 ETT BERMAN

For technical information and application notes, contact: Components Division, The Bissett-Berrnan Corporation, 3860 Centinela Avenue, Los Angeles, Cali-
fornia 90066. Telephone: Area Code 213, 390-3585.

Electronics April 15, 1968

Circle 213 on reader serv.ce card

213

Becouise of new Idea: from Benders ...

Flexprine circuitry matches coax capacitance

There had to be a way to control and stabilize capacitance
within alimited area. By matching coaxial capacitance through careful selection
of dielectric materials, constant capacitance can be predetermined and controlled through the entire FLEXPRINT Circuit.
The result is a lightweight, stable circuit that conforms to the
spherical surface of the package, matches standard coaxial cable and connectors and is 100°/o reliable.
If you have acomplex circuit problem with unique characteristics and no solution in sight, FLEXPRINT Circuitry may be
the answer. Call or write Sanders Associates, Inc., FLEXPRINT Division, Grenier Field, Manchester, New Hampshire 03103.
Phone: (603) 669-4615.

This sophisticated multi-laye circuit, used in the Northrop Nortrorics Floated Ball inertal platform for the C-5A Galaxy,
is designed for extremely close tolerances. It utilizes fine-line etching
and consists of two shields and one circuit layer. The circuit requires only 1/3 the space of conventional cable and permits a 20% weight savings. This totally encapsulated circuit provides constant capacitance values over
awide temperature range.

Creating New Directions
In Electronics

ET TE SANDERS ASSOCIATES INC

Circle 214 on reader service card

SA EZ1 SA.NDER,S

FLEXPRINT

DIVISION

GRENIER FIELD, MANCHESTER, NEW HAMPSHIRE

New Subassemblies Review

woe

Bipolar logarithmic amplifier model 2369 occupies 0.5 Cu in. Maximum error is ---L-1% typical. Fea-
tures include current or voltage signal input, and 100 db dynamic
range. Applications include non-
linear bipolar function generation, and compression of transducer output. Price is $71 each for 1-2,
$65 each for 3-9. Optical Electronics Inc., Box 11140, Tucson, Ariz. 85706. [381]

Lumped constant Chip Series delay lines serve low profile, high
density packaging. Standard sizes range from 0.515 to 2.815 in length; width on all packages, 0.610. Thinness of the package is
0.110. Eleven baic models offer nsec delays from 2.5 to 50 in the 125-Mhz cut-off range. Valor Electronics Inc., 13214 Crenshaw Blvd., Gardena, Calif. 90249. [382]

Series 20 DiGiCator is a 7-seg-

ment, incandescent, lighted nu-

meric readout. The multiple char-

acter display is contained in an

integral package 1/ 4 in. thick.

Each character measures 1 in,

high by

in. and is readable to

50 ft in bright daylight ambients.

Price is $7.95 per character in

1,000 lots. Discon Corp., 4250

N.W. 10th Ave., Fort Lauderdale,

Fla. 33309. [383]

Power module B3D converts 28 d-c to any output voltage from
5 to 2,080 y d-c at 30 w. True hermetic sealing and encapsulation
enables units to meet MIL-E-
5272C at 100°C. Units feature isolation of inputs and outputs, and output voltage adjustment
range of 12%. from nominal. Price is $304 up. Abbott Transistor
Laboratories Inc., 5200 W. Jefferson Blvd., Los Angeles. [384]

Dual digital display series NQT
employs multiplexing techniques. The complete decoder-driver and display module is 1.97 in. high, 2.20 in. wide, 2 in. deep, and sells for less than $19 per decade in production quantities. The unit
will accept 4-line BCD inputs at
IC levels and requires only 105125 y a-c power input. Mesa Co.
Inc., 220 Mill St., Bristol, Pa. 19007. [385]

Carbon dioxide gas laser model CO2100, for cutting and slitting
nonmetals, has a power output adjustable up to 100 w at a 10.6-
micron wavelength. Specifications include a beam diameter of 1.5 cm, a beam divergence of less than 2 milliradians, and a focus
spot size down to 0.004 in. in diameter. Price is $11,900. West-
inghouse Electric Corp., Box 8606, Pittsburgh, Pa. 15211. [386]

A compact modular converter can accept 6 BCD digits on 24 lines and convert them to 20-bit nat-
ural binary output. It facilitates decimal to binary conversion in such areas as programing switches, computer input typewriters, and
BCD outputs from digital voltmeters to a computer. Price is $390; delivery, 60 days. Texas Instruments Inc., P.O. Box 66027, Houston 77006. [387]

D-c power supply model 901, de-
signed for elergizing operational amplifiers, delivers 40 ma at ±15 v. Up to 4 op amps, each with
10 ma max. supply current, can be operated simultaneously. The unit is encapsulated into a 22/2 x 31/ 2 xZ's in. o-c mounting module Price is $39 each in 10-piece lots;
delivery, from stock. Analog Devices Inc., 221 Fifth St., Cam1. ridge, Mass. 02142. [388]

New subassemblies

Wang offers grown-up calculator

380 System has 640-step programing capability on punChed cards or cassette-loaded tape

When Olivetti unveiled its Pro-
gramma 101 desktop calculator in 1965, it also unwrapped a fresh
market for electronics. This new breed of machine incorporated the features of existing calculators--addition, subtraction, multiplication, and division--and added two key

characteristics of the digital com-
puter: Operation on a stored program (in this case magnetic cards Nvith a 120-step program), and the ability to base an instruction to it-
self on the results of aprevious instruction or a set of instructions.
What's more, the 101 did all this

Electronics IApril 15, 1968

215

We're not the nation's best-kept secret any more! Albuquerque ...Sunshine. No crowds. No smog. You can golf and ski on the same winter day. Two universities, outstanding recreation outdoors. Symphony, opera, much more, in unique New Mexico Contact: Albuquerque Industrial Development Service
400-X Elm N.E., Albuquerque, New Mexico 87103
Circle 216 on reader service card
Our little black book has over100,000 phone numbers.
You never had ablack book like it. Over 1,500 pages. And those phone numbers! More than 100,000 telling you who to call/where to go, for the over 4,000 different product categories listed and advertised in the yellow pages of the Electronics Buyers' Guide. It's the industry's one-stop shopping center that lets you find the products and services you need quickly. You can depend on EBG.
Electronics Buyers' Guide
A McGraw-Hill Market Directed Publication, 330 West 42nd Street, New York, N.Y. 10036

... new keyboard works
with older units...
for only $3,200. Growing up. Since then, such
calculators have become more and more common in offices. They've also become faster, smarter, and less expensive. Now Wang Laboratories Inc. of Tewksbury, Mass., has introduced another advance in the field: a 640-step programing capability, optional printout, and a program on casette-loaded magnetic tape. Punched cards also can be used with the system--which is dubbed the 380--and it is compatible with other Wang units.
The system consists of a keyboard costing $1,500, an electronics package called the 362E for $2,295, and an electric typewriter for the printout priced at $1,500. The total: $5,295.
This calculator, says the company, fills aprice gap in its product line, which includes machines costing from $1,300 to $10,000. The device can handle long programs and provide speeds up to 10 times faster than existing Wang models because of the tape capability. The tape itself, two-track and available in lengths of 80 to 640 steps, runs at 18 steps per second; the machine can use cassettes available from Wang or those already on the market.
Split. While the new keyboard can be used with other Wang electronics packages, the 362E offers more storage. It provides 12 storage registers, each including aplus or minus sign, decimal point position, and 12 digits. When only data is stored, each register may be split in half to provide up to 24 six-digit registers. The 12 registers also can serve as accumulators with floating addition and subtraction, positive and negative numbers, and results to 12 digits. And there are two additional accumulators standard for use with all Wang units.
The printout, on a 379-5 output typewriter, operates at 13 characters per second. Connected through the control unit to the keyboard, the printout can be controlled by the program or by the calculator's keyboard input.
Display. There's one other data output option--an oscilloscope-

216

Electronics IApril 15, 1968

The new Mann Type 1600 Pattern Generator produces circuit patterns, directly, at 10X final size...automatically

bavid W. Mann Company, long arecognized leader in the development of photomask systems, has added anew concept in automation and precision to high-volume photomask production ... the Type 1600 Pattern Generator.
The Mann Type 1600 Pattern Generator is afully automatic, computerdirected, highly accurate, and reliable system. It generates circuit patterns directly, at 10X final image size, without intermediate artwork generation and reduction. Turnaround time is greatly reduced, repeatability and reliability are assured, and The process is carried out in far less time than conventional methods. The circuit patterns produced by the 1600 are further photoreduced and repeated in arectangular array to fo -m a

photomask using aMann Type 1480 Series Photorepeater.
The Type 1600 Pattern Generator features:
Input data on punched tape in either decimal or binary format. Stage positional precision of ±-0.00001 inch over a2inch by 2 inch square area. Stage positioning accuracy of -±0.00005 inch over a2inch by 2 inch square area. A maximum aperture size of 120 mils square per exposure for composing circuit pattern, aminimum of 0.5 mils.

DAVID W MANN COmPANYI

PATTERN GF,I

4

High resolution ... 650 lines/mm over the entire circuit pattern area.
A digital computer controls all automatic functions of the 1600 from punched tape input data. (Optional punched card or magnetic tape input is available.) Input data on the 8-channel punched tape includes: X and Y coordinates of the center of exposure, height and width dimensions of the rectangular exposure, and the angle of aperture rotation (an option) up to 89°. Height and width of the area exposed in asingle flash on the 10X pattern may be varied in 240 discrete steps from 0.5 mils to 120 mils ... atotal of 57,600 sizes. The Mann Microset Scale for both the scanning and stepover axes assures positional precision of ±-0.00001 inch.
We'd like to show you how the Mann Type 1600 Pattern Generator fits your requirements.

DAVID W MANN COMPANY
Middlesex Tpke.. Burlington. Mass. 01803, Tel: 617-272-5600

Electronics April 15, 1968

Circle 217 on reader service card

217

AC/DC SIGNAL SOURCE
Ballantine Model 421A Precision Calibrator with Model 2421 Error Computer

aimed primarily at the science-oriented user. It, too, can interface with other Wang calculators in line with the company's policy of introducing new models on a building-block concept to avoid letting its older equipment slip into obsolescence.
Up to four basic 380 keyboards
can be used with each electronic package, and keyboards may be spotted up to 500 feet from the package.
Wang Laboratories Inc., Tewksbury, Mass. [389]

New subassemblies
Buffer talks fast but keeps still

Model 421A provides an accurate, stable source of voltage in a typical production Q.C. set-up. Other instruments measure levels at several points. Model 2421 Error Computer speeds up measurements
by changing the 421A output by an accurately indicated percentage.
Generates ±DC, or AC at 400 or

1000 Hz, RMS or Peak-to-Peak

The Ballantine Model 421A Precision Calibrator provides an accurately known stable source of ac or dc voltage for calibration of voltage sensitive devices, or for measurements of gain or loss, or as asource for bridges or strain gauges. The output may be + or -dc, or it may be ac at 400 or 1000 Hz, rms or peak-to-peak. Accuracy to 111 volts ac or dc is 0.15%, and from 111 to 1110 volts ac is 0.3%. A high order of stability is obtained by monitoring the input to the attenuator with abridge circuit whose output compensates for effects of changing line voltage, aging tubes and ambient temperature.
Model 2421 Error Computer is an optional accessory which, when connected to Model 421A, provides for achange in its output up to ±5%, as read directly on the dial of the 2421. The device under calibration is fed its nominal voltage by setting the voltage knobs on Model 421A. The dial on the 2421 is then adjusted until the device reads its nominal voltage, and the % error of the device is then directly from the scale of the 2421.
Write for Brochure giving full Specifications
If you have aproduction line O.C. requirement for aknown stable source of dc or ac, and ameans for measuring % deviation from anominal value, the 421A Calibrator and 2421 Error Computer may be exactly what you need. Write us for full details today.

eel% 11?

Prices: Model 421A, $660; Model 2421, $75.
BALLANTINE LABORATORIES INC.

Boonton, New Jersey

CHECK WITH BALLANTINE FIRST FOR DC AND AC ELECTRONIC VOLTMETERS/AMMETERS/OHMMETERS, REGARDLESS OF YOUR RE. OUIREMENTS. WE HAVE A LARGE LINE, WITH ADDITIONS EACH YEAR. ALSO AC/DC LINEAR CONVERTERS, AC/DC CALIBRATORS, WIDE SAND AMPLIFIERS, DIRECT-READING CAPACITANCE METERS, AND A LINE OF LABORATORY VOLTAGE STANDARDS FOR 0 TO 1,000 MHz.

218

Circle 218 on reader service card

Memory can put 4,800 bps
on line, cutting costs:
has no moving parts
Fast talkers don't usually save anyone money, but Digital Devices Inc. has developed one that does. It's a buffer without moving parts, the 608E-2, that stores 8,192 bits, as 5- or 8-bit words, and, on command, dumps them on aline at up to 4,800 bits per second. This speed can cut costs of leasing a line, which are often based on how long it's used.
Information fed to the buffer enters a shift register, then goes in serial form to the memory, amagnetostrictive delay line. When the dump signal is received, the information is transferred into an output register and out to the line. The buffer is also used at the receiving end to accept data fast and feed it to slow devices, such as printers. The output can be serial or parallel. A device to adjust the data-output rate is optional.
Paul Bauer, a sales engineer at Digital, says he expects his first customers to be designers of teletypewriter installations. He says the delay-line buffer may eventually replace paper-tape buffers in large telecommunication centers.
Time for silence. The buffer can
Electronics lApril 15, 1968

Now, you'll be pinning down your control system designs faster, easier, and with far greater economy

Over 200 micromodules from Philco-Ford's WDL Division stand ready to accept your system challenge. In compatible 5 to 40 MHz logic, standard DTL and T2L circuits, they contain some of the most sophisticated designs in today's stale-of-the-art, including multiplexers, operational amplifiers, D-to-A and A-to-D circuits, and an extensive array of computer interfaces.
The micromodules employ monol;thic IC's, using thinfilm and discrete components only where necessary. A hard nylon cover keeps out dust, protects c'rcuits against damage. Clegrance holes at the top of the micromodule provide fast front-panel access to all inpLc /output termina s. No reed to troubleshoot from the back! A color-

coded label identifies module type at a glance. The mIcromodule's modest dimensions, coupled with
the complexity of the logic it contains, permits highly effective packaging density. A 180-module system can be mounted in adrawer only 31/ 2 " high by 19" wide. Modular systems fit readily into rack mounts, bench mounts, or portable instruments. In service for over three years at NASA's Manned Space Flight Center in HoJston. WDL micromodules have compiled an excellent record of performance reliability. Write Product Sales Manager, WDL Division, Philco-Ford Corp., Mail Station C-41, 3939 Fabian Way, Palo Alto, California 94303. Or telephone (415) 326-4350, extension 6017.

ADD (Automated Design and Documentation) This Philco-Ford computer-programming service generates system decumentation al acost significantly below that of hand-prepared equivalents The co -nputer pragram error checks design input data, optimizes the arrangement and sequence of wiring instructiors, calculates wire lengths, provides wire lists sorted by length and
by name, and maintenance lists. The program isavailable to all users of Philco-Ford micromodules.

PHILCO
PiilLCO-FORCI CORPORATION WOL Oiyls.on ·3939 Patna," Way Palo Ato. Cal.forma ·94203
rbyrlo 91Q nn naarlor earuiro rani

Play" Wee-Fils
THE NYTRONICS FILTER GAME
Match your custom filter requirements to aNytronics standard filter!

...buffer holds data
at remote sites.
also be used to feed a computer. The longer a central processor is tied up, the higher the user's expense. By storing data or commands from a card or tape reader until they're complete, and then dumping them into the processor, the 608E-2 reduces processing time.
Other applications are being considered. For example, the buffers could be used for prolonged data storage at remote sampling sites where such conditions as weather, traffic, or pollution are measured. This would eliminate continuous communication with sites; the stored data would be transmitted periodically to aprocessing center on command.
Memory under stress. The magnetostrictive delay line holds an electrical signal 10 microseconds for every inch of wire.

IMPEDANCE (OHMS)

500

IMHz

CUTOFF FREQUENCY

THE F

LLPARK

Low-pass and high-pass Wee-Fils are available with 20, 35 or 50 db attenuation. Order Wee-Fils if your frequency-impedance characteristic falls in the feasibility ballpark.
Our in-house supplies of standard variable inductors and molded capacitors enables Nytronics to meet Wee-Fil orders with off-the-shelf components. And Wee-Fils offer all these features: · Molded Construction ·Mil-Quality Components ·Specification Flexibility · Small Size · Low Cost · Rapid Delivery
Play Wee-Fils today. It might just be your most rewarding game in filter history.

ARE YOU IN THE BALLPARK?
To play in the Wee-Fil league, both input and output terminating impedances must be the same. Write for aset of detailed rules showing each filter and its attenuation--(normalized) frequency characteristic.
ARE YOU OUT OF THE BALLPARK?
Take heart. You may still be a winner. Nytronics offers custom filters too. Consult your nearest representative.

rPyiNsri.naivrc e, xmc.
Third Avenue · Alpha, New Jersey 08866
(201) 454-1143 · TWX 201-855-2551

220

Circle 220 on reader service card

Hang-up. Buffer is constructed for rack-panel mounting.
Certain alloys are deformed by a magnetic field. In a magnetostrictive line, the input signal passes through acoil and induces amagnetic field at one end of a nickelalloy wire. The field induces astress wave that travels in the wire at about the speed of sound. At the other end of the wire another coil produces amagnetic field that induces the output signal. In memory applications, this output is continually fed back to the delay-line input. Since the output is the second derivative of the input, integrators are used in the feedback loop.
Bauer says that where an engineer can live with millisecond access times and thousands-of-bits storage levels, magnetostrictive delay lines are the most efficient and economical memory.
The 608E-2 costs less than $1,000 and is delivered in 12 weeks. It's compatible with most standard logic circuitry.
Digital Devices Inc., 200 Michael Dr.,
Syosset, N.Y. 11791 [390]
Electronics IApril 15, 1968

Don't let the good lookc of Honeywell's MS Taut-Band Meter fool you.
What \ou see is acanbination of functional advantages.
Modern curve.
The concave cover gives the meter a very contemporary look, alright.
But besides: By curving the cover, we minimized glare an: shadows. That makes the meter elsy to read.
Clean face.
We uncluttered the face by leaving out all the extraneous data. We

made the scale longer. We printed the numbers above the scale.
Very stylish. But also very easy to read.
More window
We made the sides of the cover out of crystal-clear Plexiglas, iust like the front of the cover. That makes the whole meter sparkle.
It also brightens the dial by letting more light in.
The specs.
As for the insides of the meter. the Honeywell taut-hand mechanism is completely frictionless, sa it responds to even the slightest inputs.

Hysteresis-free, so its repeatability is near perfect.
Honeywell Series MS Taut-Band Meters come in 20 standard colors. In 33 standard ranges. And 3sizes (11/ 2 ", 21/ 2 "and 3½").
The price.
This is the taut-hand meter that costs even less than apivot-andjewel meter.
So if you like it, there's nothing to keep you from having it.
(We'd like to send you acatalog. Write Honeywell Precision Meter Division, Manchester, New Hampshire 03105. )

Electronics! April 15, 1968.

The Classy Meter from Honeywell
It takes all kinds of meters to make the Honeywell line.

Circle 221 on reader service card

221

Small wonder:

POWER ON

RESET

DISPL AY

GA Et

SENSITIVITY

Our new "4th-generation" 12.5 MHz universal counter/timer. Wonderful versatility in awonderfully small package -- at an even more wonderfully small price.

With the new Model 100A you can measure average frequency, frequency ratio, single period or time interval, or count total events. It has a crystalcontrolled clock, Monsanto integrated circuit construction, and built-in compatibility with a rapidly growing assemblage of accessory modules.
With its $575* price tag (accessory modules are pegged at comparably modest rates) you can have bigleague counter/timer performance at

222

Circle 222 on reader service card

costs never before possible. Small wonder we are selling (and delivering) Model 100A's just as fast as we can build them.
Call your local Monsanto field engineering representative for full technical details, or contact us directly at: Monsanto Electronics Technical Ctr., 620 Passaic Avenue, West Caldwell, New Jersey 07006. Phone (201) 2283800; TWX 710-734-4334.
'U S PrIce. FOB West Caldwell, New Jersey

ELECTRONICS
Electronics lApril 15, 1968

New Instruments Review

X-Y recorder model 30 records on 81:2 x 11 in. graph paper, with an accuracy of better than 1%. Pen slewing speed is 10 ips. Span is continuously variable from 100 mv/in. to 1 v/in. Input resistance is 100 kilohms, and the X and Y channels are electrically independent. Overall dimensions are 14 x 10 x 10 in. Yeiser Laboratories, 881 W. 18th St., Costa Mesa,
Calif. 92627. [361]

R-f millivoltmeter model 91K has an input impedance greater than 4 megotuns shunted by 2.5 pf
at frequencies up to 25 Mhz falling to about 1 megohm shunted by 2.5 pf at 100 Mhz. Frequency
coverage is 0.5 to 600 Mhz with 8 ranges of sensitivity from 10 mv full scale to 30 y full scale in a 1-3-10 sequence. Price is
$680. Boonton Electronics Coro., Parsippany, N.J. 07054. [362]

Chatter and transfer detector model BR-650 monitors and indicates undesirable opening or closing of active circuit paths during dynamic environmental tests such as shock, acceleration and vibration. The unit provides 8 channels with 4 inputs per channel in either chatter or transfer mode. Bunker -
Ramo Corp., Defense Systems Division, 8433 Fullbrook Ave.,
Canoga Park, Calif. 91304. [363]

Sweep and inarke' generator 1484A is a low cost, solid state unit. Frequencies may be selected up to 1 Ghz, and pulse markers, c-w and harmonic birdie markers, r-f turn-off markers and postinjection markers can be specified. A 4-position switch selects band positions, and remote control of bands and tuning can be provided.
Kay Electric Co., Pine Brook, N.J.
07058. [364]

ri*ill: 4f o WI, ·

Pulse generator 113 has built-in
burst capability. Two repetition
rate oscillators are used. A h-f oscillator gives rep rates from 500 khz to 250 Mhz. A 1-f oscillator (0.5 hz to 500 khz) is used to gate the h-f oscillator for 10 nsec to 10 itsec bursts or as a trigger for low rep rates. Price
is $3,375. Datapulse Inc., 10150 W. Jefferson Blvd., Culver City, Calif. 90230. [365]

Capacitance bridge 273 operates on 9 ranges, from 0 through 120 pf to 0 through 12,000 if. Accuracy is ±- 0.1% on middle ranges, O.3% on the highest. Effects of lead resistance are eliminated by a 4-terminal kelvin connection, and a high value internal standard reduces effects of shunt capacitance. Electro Scientific Industries Inc., Science Park
Dr., Portland, Ore. 97228. [366]

Digigraph converter model 1000
transforms perforated-tape data into analog voltages for plotting
on X-Y or incremental advance recorders. Featuring logarithmic
conversion of linear data, it has
facilities for overlays of data from separate tapes and from different portions of the same tape for
comparison and de:ailed analysis. Unimetrics Corp., 2712 S.W.
Freeway, Houston 77006. [367]

X-Y recorder 6756 has a 6-pen X-Y or T-Y recording capability. The X or paper axis can be driven
with an analog input or on a time base by push button selection. Speed rangs are 0.5, 0.1, 0.2, 15, 1 and 2 in./sec, in./min., and in./hr. Each pen axis has 36
voltage ranges from 0.2 mv/in. to 100 v/in. Houston Instrument
Die, Bausch & Lomb Inc., Bell-
aire, Texas 77401. [368]

New instruments
Linear IC tester checks 22 values

Measurement system serves the needs of both the design engineer and the circuit inspector

Trying to impose order on the
chaos of parameter definitions and test procedures for linear integrated circuits bought from different makers, two engineers wound up designing their own low-cost linear lc tester.
Robert Bisey and Frederick Gans,

of the Grumman Aircraft Engineer-
ing Corp.'s Microelectronics Laboratory, began by defining 30 parameters and outlining how to measure each. Most of their definitions and tests are being included in MIL STD 883 [Electronics, Dec. 11, 1967, p. 26].

Circuit shown. Panel of 401 is schematic of test circuit.
Available lc test equipment, they found, was either too limited or too expensive for Grumman's use. Most instruments were built with aspe-

Electronics IApril 15, 19E8

223

TAKE IT FROM BEETLE BAILEY:
e FOR PANEL METERS, COUNT ON GENERAL ELECTRIC'S SALES AND SERVICE ARMY!

HEY, 5AgGE! GENERAL. ELECTRIC NA5 A eALE5 Ate GEZVIcE ARAAY READY TO HELP PANEL METER
CU9TOMER5 ATA MOMENT'6 NOTICE/

Í WA-re RIGA·ri GIR -rNEy eAlt, GENERAL ELECTRIC 1-1A5 Nie OWN SALEG AND SERVICE ARMY/

224

Circle 224 on reader service card

NO 51g, BUT
GENERAL ELECTRIC'S READY TO HELP PANEL METER CLJ5TOMER5 AT
THEIR COMMAND._

ILLIAmPERES

. . . just give the order. General Electric's Sales and Service Army is prepared to combat any panel meter problem with an arsenal of powerful, up-to-date weapons--a full line of quality panel meters and meter relays, expert application assistance, fast service across the country, and on-time delivery from a nationwide network of sales offices and distributors.
Why fight it? Surrender all your panel meter problems to General Electric's Sales and Service Army. Contact your GE Electronic Components Sales Office or your dependable General Electric panel meter distributor. 592_34

GENERA

ELECTRIC
Electronics April 15, 1968

... schematic layout of 401 panel allows designer to see changes in test circuit as he makes them...

cific maker's set of tests in mind, and there wasn't anything that could measure more than 15 parameters. So Bisey and Gans designed aunit that could measure 22 parameters, according to their own standards.
Now, under a licensing agree-
ment, Integrated Circuit Measurement Corp. will build and sell the Grumman tester, the Model 401.
Out of steps. The 401 handles any ic package because the circuit being tested is plugged into asocket mounted on aprinted-circuit board. The board, in turn, is plugged into the tester. The operator electrically
connects the lc leads to the test circuits with sliding switches on the 401's front panel. Tests can be run on the main types of linear ic's-- single-ended input and output amplifiers, differential input and output amplifiers, and differential input and single-ended output amplifiers.
Bisey and Gans were thinking of the system designer when they laid out the front panel of the 401. Symbols, labels, switches and knobs are placed so the designer can see, schematically, the test circuit in use. And when he throws aswitch, he knows immediately what part of the test circuit he's changing.
Rather than outlining test procedures step-by-step, the 401 instruction manual shows block diagrams of the 22 test circuits. This feature, combined with the panel layout, means easy and quick setups.
Yes or no. Besides being a design tool, the 401 is useful for making go-no go tests on large batches of ic's. P-c cards are made up for avariety of tests, and given to an inspector. For agiven test, he plugs a card into the programed-amplifier socket on the 401's front panel and the card by-passes the sliding switches and makes the necessary connections for the test. The inspector then just plugs an lc into the test socket, pushes a button, looks at ameter, and accepts or rejects the lc.
The designers of the 401 kept the price under $2,500 by omitting input sources and readout devices on the grounds that the auxiliary

equipment needed to operate the tester would be available in most laboratories.
Most tests have been designed so results can be read as output voltages. The accuracy of the readings depends only on the accuracy of the auxiliary equipment.
Extra equipment can be bought with the 401, including: an oscilloscope with differential input, ad-c vacuum tube voltmeter, an a-c voltmeter, adual voltage power supply, an audio oscillator for measurement of dynamic parameters, and aradio frequency generator for the measurement of bandwidth.
Integrated Circuit Measurement Corp., 55 Northern Blvd. Greendale, N.Y. 11548 [369]
New instruments
Recorder can go to the action
Portable unit has four
channels, operates on
a-c or d-c, costs $2,900
A scientific investigator working outside the laboratory has usually had to pay ahigh price for arecorder with more accuracy or channels than he needed because nothing else was available.
Engineers at the Sony Corp. had this researcher in mind when they designed the PFM-15 data recorder. It costs $2,900, weighs 37 pounds, and can be powered by a12-volt battery. It records, by frequency modulation, four channels of data on 1/4-inch magnetic tape. Associated with one channel is an audio amplifier and speaker, so the researcher can record his own playby-play.
Variable power. Line voltage from 50 to 400 hertz at levels of 100, 110, 117, 125, 220, or 240 will also power the PFM-15. Switching to a-c operation requires changing one module and setting a

Electronics April 15, 1968

YOU CAN BUY
GENERAL ELECTRIC PANEL METERS
AT:

ALABAMA Birmingham Electronic Suppl,es, Inc Forbes Distributing Co. Huntsville Cramer fliuntsvitle Edgerly Instrument Labs. Inc. Electro-Tech. Inc.
ARIZONA Phoenix Hamilton Electrool Mixon. Metercrall Inc.
ARKANSAS Little Reek Carlton Bates Co.
CALIFORNIA Cube, CitY Hamilton Electru Sales Emeryville General Electric Supply Co. Glendale 1S0 Engineering Les Angeles General Electric Supply Co. Metermaster, Inc. ML View Hamilton Electro Sales Palo Alto Kivu'', Electronics Redwood City Fortune Electronics Sacrament. Sacramento Elec. S,Pii Co. San Diego Kendal Electronics Hamilton Elect ut San Diego
COLORADO Denver Electronic Parts Co. L B. Walker Radio Co.
CONNECTICUT Hamden Cramer Electronics, Inc Hanlon General Electric Supply Co
DISTRICT OF COLUMBIA Weahingten Cramer/Washington Siberne Relio Electronics
FLORIDA FL Lau ddddd le Cramer/Florida Electronics Jacksensille General Electric Supply Co. Orlando Electro-Tech, Inc. West Palm Beach Mountain EleclronicS
GEORGIA

Electronic Supply Co.
General Electric Supply Co. Jackson Electronic Supply Co. Augusta General Electric Supply Co.

Electro-Tech. Inc.
ILLINOIS Waage Allied Radio J. G. Bowman 8 Co. Iberia Hendricks Elec. Co. Schiller Path Pace Electronics Supplies Springfield Bruce Electron., Inc.
INDIANA

Ohio Valley Sound, Inc. Fort Wayne Fort Wayne Electronac Supply Co Indiannells General Electric Supply Co. Graham Electronics Peerless Elec. Supply Co.

IOWA Cedar guilds Hupp Electric Motors, Inc. Iowa City Hupp Electnc Motors. Inc

KANSAS Wichita Radio Supply Co.

KENTUCKY Louisville P. I. Burks Co. General Electric Supply Co.

LOUISIANA Ben Rouge Sterling Electronàcs Lafayette Ralphs or Lafayette New Orlon. Argo Manne Supply New Orleans Electric
Supply. Inc. Sterling Electronics. Inc.

MARYLAND Wine. Cramer/Baltimore Edgerly instrument Lahorator .es

MASSACHUSETTS Ronan General Electric Supply Co. Gerber Rade Supply Co. Umbrae E-T Instruments 8 Controls. Rio. Lawrence Alca Electronics Needham Instruments, Inc. Newton Cramer Electranics Inc. Springfield T. E CusMng. Mc.

MICHIGAN Detroit General Electre Supply Co. Fennble Ram Meter. Inc. Kalamezoo Warren Ream Co. Mu. ...., Fitzpatrick Etectroc Supply CO. Southfield S. Steeling Co.

MINNESOTA

Mi

lis

Electronic Center. Inc.

Lew.gonn Co.

MISSISSIPPI Jensen Ellington Electronic Supply. Inc.

MISSOURI leplIn Noonan Elec, Supply Co, Inc. Kansas City General Electric Supply Co Reclici Labs, Inc. University City Olive Industrial Electron.. Inc.

NEIRASKA Lincoln Scott Electronic Supply Corp. ameba Sc meatier Elec. 8 EquiPmenl CA. NEW JERSEY
E, Instruments &Controls. Inc. Scotch Plains TUF Electronics NEW MEXICO Allniquarque Ehit ironic Pans Co.. Inc. Sterling Electronics. Inc. NEW YORK Elmhurst Cramer/ ESCO Elmsford Melvéne Race, Cotp. glens Falls Glens Falls Electric Supply Co. Great Neck AIM Instrument Latham Latham Electric Supply Corp. Liverimel WEI, Inc. New York City ET Instruments 8, Controls, Inc. Hudson Electi,c Sales Co. Porter Instrument Control Sup.
Mather, Enns and Diehl, Inc. MORT/I CAROLINA 'Marlette Don Recite Szpply Co, Inc
General Electric Supply Co. Southeastern Radio Supply Rene Southeastern Redo° Supply Co. OHIO gluon Sun Rade Cincinnati General Electroc Supply Co. United Radio, Inc. Clenlend Christie Laboratorns, Inc. General Eledric Supply Co. Pioneer Standard Electronics Inc. Ceti/min Buckeye Electronic Distri, Inc. Dayten Pioneer SlandardiSrepCO Toledo Hilleband Electric Supply Warren Radio Co. Warren REM Electronics Supply Co. OKLAHOMA Oklehente City John H. Cole Co. PENNSYLVANIA Allentown A A. Peters, Inc. Hartieinrs Radio Distributong Co.
Barno Radio Co. Philadelphia Vino Industrial/Electronics Inc. General Electric Supply Co. Sunshine Scientific Inst Pittsburgh Edgerly Instrument Labs. Inc. General Electric Supply Co. Verb Rosen Electronics RHODE ISLAND PrevIdence W. H. Edwards Co. SOUTH CAROLINA Charleston VTolesale Radio SUPPW Celumbla Dime Radio Supply Co.. Inc. Greenville Dixie Rad oSupply Co.. Inc. TENNESSEE Chatteneep Electric Motor Sales and
Supplies Harpe Electronic Distributors Kneeling Cherncity Electronics General Electric Supply Co. Memphis Elec. 8 Mech. Cornp. Devices Lavender Radio A TV WA W Distributing Co. Nashville Electra Distributing Co.
r TEXAS anee Electronics Beaumont Sterling Electronics, Inc. Corpus Chriati Electronic Equip. A Engrg. Co.
Contact Electronics Graybar ElecMc Co.
15Acl'er col I
Busacker Electronic Equip. Co. General Electric Supply Co UTAH Salt tale City S. R. Ross, Inc. VIRGINIA Norfolk Cain Electronics. Inc. Richmond Meridian Electronics, Inc. Roanoke Peoples Radio &
TV Supply Co.. WASHINGTON Aberdeen CAC Electronics Seattle Hamilton Electra Corp. Instrurnnt LibeâtOry. Inc. I(,'multi Electronics Spokane Ind. Instrument Supply Co.
WEST %um«
Ilaallald Meyers Electronics, be. Charleston Cherntity Elecbonics Mountain Electronics Co. Mountain !Intranet Corp. Huntington Electronic Supply Co. Mountain Electronics Co. WISCONSIN Appleton Gene al Electric Supply Co. Green gay Beernster Electric Co. West All,. Marsh Radio Supply Co.

ac circuit design stars with an oscillator...
START WITH THE BEST

Hewlett-Packard invented the first stable Wien-bridge oscillator. Now
mania.
they have added several design improvements to two new solid state oscillators -- 0.5% (0.05 dB) flatness--FET's in the bridge for im-

proved stability -- -,C.1% (-60 dB) distortion--balanced butput--sync n out wi -heutdegradaticn in specs. *tow. chcoEe from 17 Inn oscillators --the widest choice nthe industry!
The new bp 204C Oscillator has a trequenc e,range of 5Hz tb 1.2 MHz. 5Vrrr soLtput. The 204C can be operated with me power. mercury battery or arechargeable battery pack. Price hp 204C. 525C-285.
The new bp 209A Dsci lator generates s multaneous sine and suuare wave outputs Dyer afrequency wave of 4-lz to 2MHz Amplitudes are independently acjustable. Output voltage is 10 VrnE fcr sine wave: 23 V peak tc-peak fou square wave. Price: hp 2094. 5320.
Star. with :he best! Get complete

information on the two new--or all 17 hp Oscillators-4room your near-
est hp field engineer. Or, write to Hewlett-Packard PaIC Alto. California 94304. Eurepe: 54 Route des Acacias. Geneva.

HEWLETT ilff PACKARD

SIGNAL SOURCES

Heart beats. PFM-15 feeds the data, obtained with recorder in intensivecare ward, to averaging computer.

panel switch to the proper voltage. The unit records linearly within
z1_-.1decibel from d-c to 2.5 kilohertz. The operator can extend the range to 5khz by making connections on one of the instrument's circuit cards. At this wider range, linearity is within +1 db and --2 d1). The
signal-to-noise ratio is 45 d1), and crosstalk is --37 db. Total harmonic distortion is under 2.5% of full output, and the recorder has an input/output level meter and a level adjustment for each channel.
A servo system, used as the tape transport mechanism, maintains a
constant tape speed of 7.5 inches per second.
Baby talk. Gerald Wade, a biomedical engineer with HoffmanLaRoche Inc. (a large pharmaceutical house), has already put the PFM-15 to use. Hoffman is working with RCA to develop an automatic monitor and alarm system for the intensive care of premature infants. The system will measure such parameters as blood pressure and temperature continuously, and when any abnormal signal is received from the infant, an alarm will sound. The key to the system is knowing what are the normal and abnormal physiological signals from apremature infant, and what are artifacts.
To find out, Wade is using a PFM-15 in the intensive care unit of Columbia Presbyterian's Babies Hospital in New York. He records a variety of physiological signals and takes the tapes back to his lab at Hoffman, where he has another PFM-15, for analysis.
Sony/Instrumentation Data Prod., 2 Maud Graham Circle, Burlington, Mass. [370]
-+-Circle 226 on reader service card

44"'"'&W.OMP·teer

..;

Ittet.lAnii.11.1( Pit

/1/

o,r."4 no. romvoa r, vrIb4 j 7fl 4 14 MA'S

Why pay more
for the "same" transformer? To find out, send for the informative booklet shown here.

Both of these transformers look alike...but they're not! The $25 transformer on the left is typical of the units which have established Raytheon's reputation for transformer quality in vital military systems. The $50 unit is a high reliability transformer. It costs more because it was designed to meet defined MTBF goals and manufactured in a separate, environmentally-controlled facility. This transformer a:so underwent rigorous screening and qualification testing to make certain it met the specified high reliability standards.

Raytheon is an experienced manufacturer of high reliability magnetic components, having participated in numerous NASA and DOD programs such as Apollo, Sert II, and MOL. Get your free copy of the Raytheon transformer brochure shown above. It describes our high reliability facilities and programs. And it shows why Raytheon's high reliability transformers are well worth the difference in price. Send the reader service card or write directly to: Raytheon Company, Magnetics Operation, 180 Willow Street, Waltham, Mass. 02154.

RAYTHEON

Circle 227 on reader service card

227

CONSIDER COLORADO 1INDUSTRIAL COLORADO New instruments

... where people have a reason to be more productive... To work harder. To be conscientious and stable. To make more effort to do a good job for you.
Consider Colorado's labor force, 750,000 strong. Well-trained in widely diversified fields. People who are willing to work hard because there's a lot to live for in their State. A stimulating climate. A myriad of recreational activities easily accessible to all. Their attitude is reflected by unemployment compensation rates which are among the lowest in the nation.
Consider opinions of companies with multi-state facilities about Colorado employees. "An enthusiastic and cooperative group of employees." "A stable work force." "Less absenteeism." "Productivity higher than other divisions." The average employee in the 25 and older age group has better than a high school education. 10.7% of that group with 4 years of college,
the highest percentage in the nation. Each year 80,000 workers improve themselves through adult education programs.
If these are qualities you want in your employees, consider Industrial Colorado for your expansion or relocation.

Wattmeter has
0.02% accuracy
Japanese calibrator uses
feedback and three moving
coils to increase linearity
It won't make electricity bills any easier to pay, but anew wattmeter from Japan may ensure that they're based on more accurate readings. Developed by Yokogawa Electric Works Ltd. as acalibration standard for wattmeters and watthour meters, the APR-2 has an accuracy of 0.02% and a repeatability of 10 parts per million. Hallmark Standards Inc., which will sell and service the unit in the U.S., claims the APR-2 is at least five times as accurate as present calibrators.
Like most wattmeters, the new device is adynamometer; amoving coil on a shaft is arranged inside afixed coil. To measure power dissipated by a load, the fixed coil is put in series with the load, and the moving coil is placed in parallel with it, so that the deflection of the moving coil is proportional to the product of current in and voltage across the load. The problem here is that as one coil rotates,

228

Skilled, unskilled, or highly specialized. Coloradans are well educated, conscientious, anxious to improve themselves and help their company-- an asset to any employer. Write for a complimen-
tary copy of Industrial Colorado, arevised-to-the-minute, factual, spiral-
bound portfolio. It covers important considerations pertinent to plant expansion or relocation in anypart of the State.
Address inquiries to Ronald D. Lemon, Director, Industrial Research & Development, Division of Commerce and Development. 78 State Services Building, Denver, Colorado 80203.

Converter. Isolation of the three moving coils allows use of feedback loop to reduce change in mutual inductance.
Electronics IApril 15, 1968

mutual inductance changes, and coil impedances change. As deflection increases, therefore, linearity decreases.
Spin stopper. In the APR-2, a feedback loop reduces deflection. There's a second moving coil inside another fixed coil on the instrument's shaft. When a 10-kilohertz signal is applied to this fixed coil, the resulting rotation of the shaft induces acurrent in the second moving coil. This current is amplified and then mixed with the 10-khz signal to produce ad-c signal, porportional to load power, that flows into an output resistor.
The mixed signal is also fed into a third moving coil situated between the poles of a permanent magnet. This signal tends to move the shaft in opposition to the rotation caused by signals from the load; and keeps the maximum deflection of the shaft under 0.05 degrees.
Isolation. Russell Brownell, engineering vice president at Hallmark, explains that the unit's accuracy stems from the fact that "power sensing, torque sensing, and deflection sensing are electrically isolated while being mechanically connected." Brownell says the feedback approach has been attempted before, but that the APR-2 is the first instrument to use three moving coils. Other feedback systems, he adds, use one or two coils and are plagued by interaction.
Accuracy is guaranteed up to 2 khz, and Hallmark says the unit gives good results up to 10 lchz. It can handle 110 volts and 5amps, and settling time between readings is less than 5 seconds.
Loss check. Although the APR-2 was designed for use in calibration labs, other applications are possible. Fuji Steel doesn't need 0.02% accuracy when it measures core loss, but it's doing the job with APR-2's anyway. Fuji uses the instrument's 0-to-1-volt d-c output to digitalize power readings.
The APR-2 comes in three parts --a converter that contains the dynamometer section, an amplifier, and astandard-resistance box. Cost is $6,650, and delivery time is six months. Hallmark hopes to eventually build the units in the U.S.
Hallmark Standards Inc., 145 Library Lane, Mamaroneck, N.Y. 10543 [371]
Electronics April 15,1968

Sleep

401

6 n

3003

IF FREQUENCIES 1-WAY RADIO

TELEMETRY HANDS i1I MIE HANDS
CHANNELS

· . Designed for TEionic's SM-2000 Sweep Generator. this new Model

·····.

3003-1 plug-in oscillator provides frequency coverage from 5 to 500 MHz, sweeping this entire range in one pass or any pertion of

it down to 500 kHz wide. Usi -ig electronic tuning and all solid state circuits, the 3003-1 virtual'y doubles
the capabilities of the SM-2000 Sweep Generator. fri additicn to wide :ange and

sweep width, it also features variable rate for permanent recording applications and

a variable birdy-type marke -.providing frequency identification from 5-500 MHz.

SPECIFICATIONS Frequency Range Sweep Width

5 MHz -500 MHz 500 kHz -530 MHz

Output Sweep Rate

Vernier Attenunation Rance

Linearity

-

Flatness @ max. sweec

@ 10% max. sweep

.5 v RMS .01 ,o 100 Hz. variable 6 d_B min. 1.5:1 _ 50.75 dB
0.5 dB

Full details plus Application Data in Ca--talog 70-A Send for your copy.

/zã INSTRUMENTS lDeivliosn.iocn Ionfdastries. Inc.
60 N First Avenue · Beech Grove, cidiana 46107 · Tel.: (317) 787-3231 · TWX -810-341-3202

Circle 229 on reader service card

229

Digitran made it big

about so big

Digitran perfected asimple idea ... the thumbwheel switch. Making it was simple. Making it perfect was abig job. We did, and called it aDigiswitch'. After we made it perfect, we made it small. We call that aMiniswitch'. MI Making it small was abig job, too. It took lots of time, talent and money. But it was worth it. Miniswitch can help you save up to 50% of your panel space; give you accurate, dependable controls that are simple, easy to set and read; under any conditions, in any environment. MI At Digitran you can count on our know-how to help solve your most complex switching probl We've the industry's most complete thumbwheel switch application library to prove it. Given the opportunity, we can probably save you both tim MI But don't take our word for it, find out for yourself. Send for acomplete catalog on switc (big and little). From Digitran. The thumbwhe switch company you can count on.
THE DIGITRAN COMPANY
Subsidiary of Becton, Dickinson and Company 855 S. Arroyo Pkwy./Pasadena, Calif. 91105 Tel: (213) 449-31 10 /TWX 910-588-3794

·
«Mer*

re- 1

New Industrial Electronics Review

Plug-in SCR motor speed control 2100 is for d-c shunt wound motors. It consists of 2 plug-in modules that are readily removed
without disconnecting wiring. Replacement is achieved in 30 sec
by unskilled personnel. The unit covers d-c motors from 1/4 to 1 h-p at 115 y a-c; and 1/2 to 2 h-p, 220 ya-c input. Seco Electronics Corp., 1001 2nd St. South, Hopkins, Minn. 55343. [421]

Solid state Fandial continuously varies fan and blower speeds from maximum to any desired lower speed within inherent shaded-pole or permanent split-capacitor capability. Standard thyristor modules FS-5 (5 amps, 120 y a-c, list price $11.95) and FS-10 (10 amps, 120 y a-c, list price $24.95) are available. Lutron Electronics Co., Emmaus, Pa. 18049. [422]

Electronic tachometers for both indication and alarm are offered in a wide choice of ranges calibrated directly in rpm, cps, mph, fpm, or special ranges. The line features accuracy of "In% and linearity of ±-1% over 9 ranges from 0 to 50 to 0 to 20,000 hz. Three sizes of meters are offered: 31,4, 41:2 and 51 2in. API Instruments Co., Chesterland, Ohio 44026. [423]

A-c motor speed control model MS-6A features feed-back for constant speed unJer varying load conditions, and a speed adjustment that enables a variation of speeds during operation. Input voltage is 117 y rms ±10%, 50-60 hz. Output wave shape is 60 hz sine wave. Maximum load current is 6 amps. Price (1-25) is $28 each. Oven Industries, Box 229, Mechanicsburg, Pa. [424]

Solid state digital-to-synchro converter model DS800 is designed
for simulation and industrial control. It accepts a 10-bit parallel
binary input and provides a completely isolated synchro output
at 11.8 v, 40 hz line-to-line, with accuracy of better than 30 minutes of arc, no load to full load, without adjustments. Astrosystems Inc., 6 Nevada Dr., New Hyde Park, N.Y. 11040. [425]

Noncontact instrument RMI-1500
is a solid state unit for measuring and controlling temperature on rotating machines, with a single sensor. Over its 0 to 1,500 °F range, readability is a constant 1/2°F. Controller action is failsafe. Accuracy is 1% of full scale absolute. Units operate from 115 v, 60 hz. S. Himmelstein & Co.,
2500 Estes Ave., Elk Grove Village, Ill. 60007. [426]

Alarm card series 625 is for single or multi-point temperature alarm
applications. It can also be used as an on-off controller for 1 amp at 120 ya-c (spst). The unit uses
a reed relay type of output for maximum reliability. It will accept
a thermocouple input, resistance bulb or other d-c input signals. Price is $45. Electronic Control Systems Inc., Fairmoit, W. Va. 26554. [427]

Fluid analyzer model 260, for in-
dustrial and processing uses, comes in ranges of 0 to 1 ppm and 0 to 300 ppm. It consists
of an in-line sensor and indicator, and the two units may be located up to 500 ft apart. Standard model process fluid temperatures
are up to 140'F, with optional temperature capability up to 450 °F. Gam Rad Inc., 16825 Wyoming Ave., Detroit, Mich. [428]

New industrial electronics

Blind controller.eyes special situations

Dropping extras, compensator based on operational amplifiers applies to 1.,Tirge and small custom projects

When aprocess controller contains wore than a customer wants to pay for, the supplier can forget about the sale or he can design astrippeddown version that competes with his own and other conventional
lines. Encouraged by customers' sug-

gestions, C. Kenneth Hines, general manager of the Control Products
division of the Consolidated Electrodynamics Corp., a Bell & How-
ell company, took the second route. The result is a blind, three-mode, electronic analog controller with a basic price of $265--more than one-

-4--Circle 230 on reader service card

231

A New X-Y Recorder... ... analog controllers introduce compensation...

That's Easier To Operate

Easier to operate ... easier to position ...and meets top performance requirements. The function! Hier* recorder is more convenient than other X-Y plotters. You can operate this new TI recorder in five differ-
ent positions to suit any application. Mount at in a 19-inch rack without adapters, stand it upright on a benchtop or position it flat with the writing surface horizontal, at a 45° or 90° tilt angle so you see the plot, even when you're sitting.
It's easy to change applications too. Three types of plug-in "function modules' allow you to plot inputs from 100pv to 50v, with time sweeps from 0.1 second/inch to 100 seconds/ inch. All modules are interchangeable between X and Y axes. Signal Input module permits single-range millivolt recording. Signal Control

module offers 16 calibrated scale
factors. Time Base module gives 10
time or voltage factors.
For more than four years, the servo system of the function/ riter recorder has been use-proved in thousands of other TI instruments. Quieter operation of the vacuum hold down (for either 81/2 x 11-inch or 11 x 17inch paper), solid-state electronics, 20 inches/second slewing speed and accuracy of 0.2% of full scale are some of the other features that make this X-Y recorder an outstanding instrument to solve your plotting problems.
There's more to the story too. Find out by asking for complete data or a demonstration from your TI representative or the Industrial Products Division, P. 0. Box 66027, Houston, Texas 77006 (713-349-2171) .
Trademark of Texas Instruments

TEXAS INSTRUMENTS

INCORPORATED 109

232

Circle 290 on reader service card

third less than that of conventional indicator controllers. The term blind means a controller that--unlike conventional counterparts--has no built-in indicators or recorders that add several hundred dollars to
the cost and often can be superfluous.
Keeping each control loop at its preset value is accomplished with analog controllers that introduce just the right amount of dynamic compensation to counteract disturbances. Because different loops exhibit different dynamics--flow loops can be fast responding whereas temperature loops can be much slower --commercial controllers have adjustments that permit the selection of the amount of dynamic response to match the characteristics. This matching is called tuning.
Blind controllers have been around for years, particularly pneumatic versions. But there's more interest in them now because experienced users are finding control applications that involve both the dynamic compensation supplied by the controller and the computation supplied by other analog modules. If needed, the computed variable is displayed.
Field-proven. The blind controller, called Model 19-417, was developed about two years ago but has been used mainly as amodule in larger systems. Some were sold as individual items, mainly to the Lubrizol Corp., whose engineers used the controllers in their engine test stands. Mostly unattended, these stands operate on a24-hour basis to evaluate the company's chemical additives for lubricants and fuel. Because these additives must be tested under many conditions, the controllers receive programed setpoints to keep engine speed, cooling-water temperature, and oil temperature at the selected values.
The blind controller has been used in amuch larger application, too. A flow of cooling water on the runout table of anew hotstrip mill, built by the Youngstown Sheet 8r Tube Co. in East Chicago, Ind., is being manipulated by these instruments. To assure adequate cooling
Electronics !April 15, 1968

Flat as apancake · · ·
and selling like hotcakes

And why not? General Electric's new high performance 150-grid sealed relays are smallest where it counts most--only 0.320" high. What's more they come in 4 versions: 4 Form C, 2 Form C, 4Form C AND-logic type, and a50 milliwatt sensitivity 1Form C (or 1A+113).
Result: for the first time you can get really small size, a variety of forms to choose from, and exceptional performance all in one relay type.
These General Electric 150-grid space relays meet or exceed the envirormental and mechanical specs of much larger Mil Spec micro-miniature relays. And compared to relays of comparable size, GE 150-grid space relays have 3times the magnetic force and over twice the contact force of the nearest competitor.
Outstanding features include:
· High vibration capability · Excellent minimum current switching ability
· Excellent thermal resistance · High overload capability--can withstand 5 amps each contact and make and
carry 10 amps for short periods · No flux contamination because of all-welded construction and design.
For more information on the small relay that's going over big, contact your General Electric Electronic Components Sales Engineer. He can tell you more about them and help with your individual application. Or write for bulletin GEA-8042B, Section 792-41, General Electric Company, Schenectady, New York 12305.
Specialty Control Department, Waynesboro, Virginia

GENERAL

ELECTRIC

Circle 291 on reader service card

WE NEED MORE GOOD ENGINEERS

MITRE has immediate openings in the following areas:
·Communications Engineers
Openings exist for communications engineers experienced in tactical communications systems. Interest and background are desired in systems analysis; design, installation and checkout of communications networks; modulation and signal processing techniques; switching systems; voice and data transmission and satellite communications and associated airborne and ground terminal hardware.
Project Engineers are needed for detailed engineering and specification of satellite communications systems.
MITRE has technical direction responsibility on such current communications systems as 490L Overseas Autovon, TACSATCOM, and Integrated Communication Navigation and Identification (ICNI). There are also openings for communications engineers on 407L, Tactical Air Control System, and related tactical communications projects.
·National Range Support Systems Development
MITRE's mission is to assist the Air Force Systems Command in its development of the future systems requirements and instrumentation plans for the Eastern and Western Test Ranges. Systems-oriented planning and research activities include studies of range functional subsystems categories: radar, telemetry, optics, communications, and data processing.
·National Airspace System
MITRE is currently augmenting its top-flight team of systems men in the suburban Washington, D.C. and Atlantic City, N.J. areas where FAA's prototype Air Traffic Control systems are now under development. Their mission: to provide the system engineering to the Federal Aviation Administration on the new National Airspace System -- an air traffic control system for the

1970's. Their job encompasses such technical areas as broad level system analysis, computer program analysis, system specifications, system logical design and system test planning for design verification.
On this project you would have the opportunity to: translate system operational objectives into technical requirements for the system's subsystems; synthesize the technical characteristics of equipment subsystems of balanced reliability, and analyze alternatives; review and analyze, at the logic level, the design submissions of system hardware contractors: conduct design optimization studies with respect to cost, reliability, and technical suitability; or to synthesize software designs for a multiprocessing computer environment. MITRE's Washington Operations also has unusual new openings for systems engineers in: Weather Systems, Defense Communications Systems and Information Systems. (We also conduct independent research in various new areas, e.g., low income housing, medical data processing, educational technology.) If you have two or more years' experience and adegree in electronics, mathematics, or physics, write in confidence to Vice President -- Technical Operations. The MITRE Corporation, Box 208BC, Bedford, Massachusetts 01730. Persons interested in Washington openings should write directly to Vice President -- Washington Operations, The MITRE Corporation, P.O. Box 1202BC, Bailey's Crossroads, Va. 22041.
MITRE will he interviewing at the Spring Joint Computer Conference in Atlantic City from April 30 to May 2. We invite you to get in touch with us at (609) 344-7021.
THE
MITRE CORPORATION An Equal Opportunity Employer (M & F)

Formed in 1958 ...pioneer in the design and development of command and control systems ...MITRE serves as technical adviser and systems engineer for the Electronic Systems Division of the Air Force Systems Command and provides technical assistance to other Government agencies, including the Department of Defense, the Department of Commerce, the Federal Aviation Administration and the OAfefriocenaouftiHcisgjasnSdpSepeadcGerAodumnidniTsrtarnastpioonr.tation of the Department of Transportation, and the National

234

Circle 293 on reader service card

without wasting water, the controllers are joined with electronic analog computing modules. These provide both feed-forward and feedback regulation. As a result, the
amount of water needed to cool the steel strip is adjusted precisely in each of 45 sections along the table according to the temperature, thickness, and speed at which the strip is moving.
Easy attachment. Control dynamics is accomplished with two operational amplifiers with adjustable resistance-capacitance net-
works. In this regard, the controller is not substantially electronically or functionally different from other controllers. But its small size, and availability via screw terminals to all salient portions of the circuit, simplify custom packaging and connection to additional circuits for computation and connection to a meter for display.
Unlike most analog controllers which have perhaps eight or 10 selectable values in each mode, the Model 19-417 has up to 516 discrete values. To get this high resolution, slide switches change the amount of resistance in the dynamics networks, the tuning-constant value being the sum of the values assigned to the individual switches. The proportional mode has seven slide switches, the reset mode eight,
and the rate mode nine. For example, with its eight switches the (fast range) controller's reset mode can be tuned in 256 steps--its lowest value being 0.5 repeats per minute with one switch actuated, its highest 188 repeats per minute with all switches actuated.

Specifications

Output
Input Fast model ranges
Proportional band Reset mode
Rate mode Slow mode ranges
Proportional band Reset mode
Rate mode List price Options Internal relay for
automatic/manual transfer 4 to 20 ma d-c output

1-5 ma d-c(or 0-10 v)
into 2,800 ohms 0to 10 vat 200 kohms
1 to 318% 0.5 to 188 repeats per
minute 0.002 to 1.88 minutes
1 to 318% 0.05 to 18.8 repeats per
minute 0.02 to 18.8 minutes $265
Add $30 Add $10

Consolidated Electrodynamics Corp., a sub. of Bell & Howell Co., 706 Bostwich Ave., Bridgeport, Conn. 06605 [429]

Electronics ¡April 15, 1968

New industrial electronic,
Servo potentiometer
charts many courses
Process-control recorder
is built for easy service
and along life-span
Servo potentiometers are as important to process control as the controller is. And because they usually run around the clock, they must be trouble-free. Honeywell Inc. designed its newest recorder, the ElectroniK Ill, so that it Yequires only routine servicing.
ElectroniK 111's automatic control units can be removed for servicing without interrupting the process. To make the recorder trouble-free. Honeywell used all-silicon circuitry, including the chopper and amplifier. Moreover, the input filter has a floating shield to minimize the effects of radiated noise, and aprecision slidewire made of corrosion-resistant platinum alloy. The slidewire has a four-finger contact so that at least one finger maintains contact at all times.
Other features include an interchangeable chassis, and a lift-out chart transport.
User's choice. The recorder is available with three kinds of outputs; current, position, and time proportioning. It uses a6-inch-wide chart that's available in drive speeds of 1, 2, 6, 10, 12, 20, 30, and 60 inches per hour. Circular charts come in 1, 4, 8, and 24 hours per revolution varieties.
The device comes as acircular or a strip-chart recorder; the characteristics are the same for both. Accuracy is ±-0.3% of span; reproducibility, -±0.15% of span; dead band, 0.1% of span; response time, 5seconds (15 seconds is optional); source resistance rating, 2,000 ohms max.; input impedance, infinite at balance, 200 kilohms min. off balance. The recorder operates in ambient temperatures up to 140°F, and costs from $625 to $1,000 depending upon control units. Delivery is 10 to 12 weeks.
Honeywell Inc., Industrial Div., MS 436, Fort Washington, Pa. 19034 [430]
Electronics IApril 15, 1968

SEVENTH INTERNATIONAL
INST MENIS ELECTRO NI CS MONTI O
EXHIBITION

OLYMPIA LONDON ENGLAND
13-18 MAY1968
Focus on Progress
New technologies are moulding the future of the World, and London is the global focal point in May '68. The IEA Exhibition at Olympia is the largest and most comprehensive show of its kind ever staged; it covers the entire structure of the technologies on which all industry depends for the future. The 1968 IEA deals in depth with the fast-changing science and engineering which has impressive impact on all forms of human activity ...from the growing of wheat to the making of automobiles ... from medicine to meteorology. International lEA is world-embracing; this year there is a15% increase in overseas participation and many countries are again presenting national 'prestige' displays. Covering 250,000 square feet of stand space, IEA will attract at least 12,000 overseas visitors. Share with them the broadening of tneir technological experience.
000 For your free Official Invitation Card and further details contact: INDUSTRIAL EXHIBITIONS LIMITED, 9ARGYLL STREET, LONDON,W1, ENGLAND

Circle 294 on reader service card

235

EECO 5000/6000 Series Photoblock Tape Readers...

PHOTOGRAPH COWZIESY w lint SIEGLER INC., ASTRONICS Div.

speed production testing

Fe _

ONE FRIME

40 U NES-320 BITS

Segment of tape showing one 40 line block of data used to program instrument ranges and comparator limits.

EECO 5000/ 6000 Series Photoblock Tape Readers can be used to program avariety of electronic test instruments. Frequently, they are the most versatile, economical method of automating the production testing of electronic products.
Tape with 5to 40 8-bit lines of test sequence data (40 to 320 bits) is photoelectrically read to program aparticular test. The 5000 Series reads at rates to 12 blocks per second (100 lines/sec) ... the .6000 Series to 20 blocks per second (200 lines /sec). Twenty output options facilitate interface with present test instrumentation.
All EECO Photoblock Readers use solid state controls and step motor drives. EECO's exclusive latching output option, which keeps output lines "latched-in" between block advance commands, allows testing to continue while the tape is moving.
Compare EECO 5000/ 6000 Series Photoblock Readers for versatility, economy and reliability with such other programming methods as single line relders with buffer memories. Ask for data sheet and prices.

INSTRUMENTS DIVISION
ELECTRONIC ENGINEERING COMPANY OF CALIFORNIA
1601 EAST CHESTNUT AVENUE ·SANTA ANA, CALIFORNIA 92707 ·(714) 547-5501

New Microwave Review

Tunable, low-noise parametric amplifier model APC-5 is compatible with C-band radar systems. It operates in the 5.4-to 5.9-Ghz range. It has a 20-Mhz instantaneous 3-db bandwidth. Noise figure is 3 db max. with 18 db of gain. Calibrated gain and frequency controls permit tuning with excellent repeatability. Melabs Inc., 3300 Hillview Ave., Palo Alto, Calif. 94304. [401]

High-Power, solid state voltagetuned oscillators can be used as VIM and BWO replacements in military countermeasures systems as well as in commercial sweep oscillators. Units measure 1 x 1 x 2 in. The 28774-66 produces 200 mw across the 2 to 4 Ghz
octave; the 287745-67, 20 mw over the 2.6-5.2 Ghz octave. Omni Spectra Inc., 24600 Hallwood Ct., Farmington,Mich. 48024. [402]

Vertically

polarized

L-bard

antenna L10-16 operates over the

range of 975 to 1,225 Mhz. Im-

pedance is 50 ohms; vswr, 1.5:1

or less. Radiation pattern is

essentially omnidirectional. The

unit is made of fiberglass and

cpoxy materials, and measures

31/ 2 in. high. Communications

Components Corp., 1524 W. 15th

St., Long Beach, Calif. 90813.

[403]

Two standard octave transistor preamplifiers, one covering 250 to 500 Mhz and the other 500 to 1,000 Mhz, are for military communication uses. Noise figures are 7.5 and 10.5 db, respectively. Both have input and output impedance of 50 ohms and gain of 13 to 17 db. Each features vswr of 2.3 to 1 max. Micro State
Electronics, 152 Floral Ave., New Providence, N.J. 07974. [404]

Multiplex passive filter 18205 has a simple r-f input and affords 4 r-f output channels at 366, 377,
410 and 456.7 Mhz. Each output has a 3-db bandwidth at 1.0 Mhz.
Channel insertion loss is less than 1.5 db (pass band). Rejection outside pass band is greater than
70 db at 18 Mhz. Microwave Cavity Laboratories Inc., 10 N. Beach Ave., LaGrange, III. 60525. [405]

The Eccoless target support columns fill the need for rugged lowre9ectivity rotatable supports to hold targets or models during
reflectivity measurements in a microwave anechoic chamber. A
variety of sizes and shapes are available. Typically the dielectric
constant is 1.03, and the loss tangent 0.0002. Price, on special quotation. Emerson & Cuming Inc.. Canton, Mass. 02021. [406]

Semiconductor microwave oscilla-
tors using the INIPATT (impact avalanche transit time) principle
and quietly delivering a nominal 60 mw c-w are for use at the fixed frequency of 10.525 Ghz in
the public service radio location band. Typical appIcations include local oscillators and in low-power railroad monitoring. Varian Bomac Division, 8 Salem Road, Beverly, Mass. [407]

Compact, lightweight coaxial balanced mixer model AM-7425 features ease of diode replacement (by removal of 2 crystal caps), result;ng in virtual elimination of system down-time. Frequency range is 1 to 2 Ghz; noise figure, 7.5 ab typical; vswr, 1.5 max. Unit measures 2 x 2.10 x 0.75 In., weighs 3 oz. Alpha Industries Inc., 381 Elliot St., Newton Upper Falls, Mass. 02164. [408]

New microwave
Cable assembly takes aturn

Flexible waveguide exhibits characteristics as favorable as those of rigid units

The performance of microwave in-
strumentation has been limited by the connector so that it was almost impossible to use the device's full capability. The development of precision, 7-millimeter coaxial connectors helped in part. But these connectors performed only to spec-

ification when used with rigid airlines. Consequently, many microwave instruments were unusually bulky.
Two developments from the Amphenol Corp. should eliminate this problem. The company has perfected the techniques for manufac-

Dual mates. Semi-rigid aluminum jacket coaxial cable accommodates either precision 7-mm (at right) or type-N connectors.

-4-- Circle 295 on reader service card

237

... designed electrically, not mechanically...

Can you

do this?

These new Johanson glass capacitors are designed to bridge the gap between conventional trimmers and high frequency air capacitors. They have high 0--low inductance; they have high RF current characteristics, they can be soldered together with components to simplify circuitry and they are strong.

1111
733°

Models include: Series Il: High RF voltage low cost units with Q> 1200 and TC; 0±50 ppm.

-4. W itet>
7168

Johanson 7168: High voltage quartz capacitors which feature 7000 VDC; 2500 V peak RF at 30 mc and current capacity > 2 amps.

Also available are: · Tuners and ganged tuners; linear within -±-.3%
· Differential capacitors · Mil spec capacitors · Microminiature capacitors .075" diameter and .1-1 pf

Write today for full catalog.

MANUFACTURING CORPORATION
400 Rockaway Valley Road, Boonton, N. J. 07005 (201) 334-2676
Electronic Accuracy Through Mechanical Precision
Circle 296 on reader service card

Our little black book has over100,000 phone numbers.

You never had ablack book like it. Over 1,500 pages. And those phone numbers! More than 100,000 telling you who to call/where to go, for the over 4,000 different product categories listed and advertised in the yellow pages of the Electronics Buyers' Guide. It's the industry's one-stop shopping center that lets you find the products and services you need quickly. You can depend on EBG.
Electronics Buyers' Guide
A McGraw -ilill Market Directed Publication, 330 West 42nd Street, New York, N.Y. 10036

turing semi-rigid, aluminum-jacketed coaxial cable that retains its diameter while being bent and twisted. Amphenol's RF division has also developed atechnique for mating precision 7-mm connectors with the cable. This technique can also be used with N-type connectors.
Besides giving flexibility to the microwave-instrument manufacturer, Amphenol's semi-rigid coaxial assemblies allow precision connectors to be used in aircraft. Coaxial cable removes the frequency restrictions on aircraft microwave systems that previously had to incorporate band-limited waveguides. In addition, the waveguides had to be preformed; the semi-rigid coaxial line can be bent and shaped as the cable is installed.
These semi-rigid cable assemblies are designed electrically and not mechanically as in the traditional approach. As a result, assemblies can be held to an impedance of 50 ±-0.5 ohms--roughly one-fifth the tolerance of the previous state-of-the-art for semi-rigid cable assemblies. Moreover, the maximum vswr (voltage standing wave ratio) is 1.15 at 12.4 gigahertz. The cable assemblies are available in four standard lengths--one, two, three, and four feet. However, other lengths are available on special order.
Previously, users of semi-rigid cable assemblies had to live with relatively large changes in impedance as the cable's diameter changed with bending. Also, the vswr changed if the center conductor shifted. For example, a change of 250 microinches in the diameter of the cable could add as much as 0.2% to the cable assembly's vswr.
Amphenol's aluminum-jacket cable is built with afoamy material between the jacket and the polyethylene insulating core material. The foamy material allows accurate sizing of the cable to achieve the 50-ohm impedance without stressing the inner conductor.
Amphenol Corp., RF division, 33 E. Franklin St., Danbury, Conn. 06810 [409]

238

Electronics 'April 15, 1968

business trips rule out
evening classes?

here's a practical way to update your knowledge of electronics

Are irregular hours, travel ard family obligations keeping you fro -7-1 attending classes--even though you
worry about becoming tech -iically obsolescert ?Check into th E.: Special Programs in Electronics for Engineers developed by CREI, the Home Stucy Division of the McGraw-Hill Book Company.
These are not simply courses, but comprehensive programs in advanced electronics offe-ing major
electives in such fields as:

Communications Engineering, Aeronautical and Navigational, Television Engineering, Automatic Control Engineering, Missile and Spacecraft Guidance, Radar and Sonar Engineering, Nuclear Instrumentation and Control, Computers.
Industry-recognized CREI Programs make it possible for you
to catch up on new developments in electronics through study in your ewn home, at your own pace,

your own schedule. Free book gives complete information and details of technical material covered. For your copy, mail coupon below or write: CREI, Home Study Division, McGraw-Hill Book Company, Dept. 1816-G, 3224 Sixteenth St., N.W., Washington, D.C. 20010.
[caned le?
Accredited .14ernbet al the Notional &tire Study Council

CREI, Home Study Division, McGraw-Hill Book Company Dept. 1816-G, 3224 Sixteenth St., N.W. Washington, D.C. 20010
Send mefree brochure describing CR El Programs in Electronics for Engineers.

NAME

AGE

ADDRESc

CITY

STATE

ZIP CODE

COMPANY

TITLE

Electronics April 15, 1968

Circle 297 on reader service card

239

New microwave
Japanese cook up cool oven with fins
Aluminum alloy dissipates
heat of magnetron that
delivers 600-watt output
The trick in using amicrowave oven is to be able to bake acake without baking the magnetron along with it.
Engineers at Japan's Matsushita Electric Industrial Co. have developed amagnetron for cooking applications that is convection cooled with aluminum-alloy fins. In most magnetron applications, heat is dissipated by forced-air or water cooling. By going to the convection technique, Matsushita has eliminated the need for fans, air ducts, air filters, and water pumps and

THIS IS "DIE-LESS
DUPLICATING"!
Produce short runs of simple parts quicker than an order can be processed to get them "outside." Use Di-Acro "DieLess Duplicating" equipment to cut stock to size and to
form it with die-accuracy -- without costly dies. Get full information in our new "Die-Less Duplicating" catalog. See your distributor, or write us -- naturally!

240

DI-ACRO
division of 43d EIGFITFI AVENUE LAKE CITY. MINNESOTA 55041
Circle 298 on reader service card

jackets. Moreover, since the technique is passive, power consumption and noise levels are low.
Serving up power. The com-
pany's magnetron delivers 600 watts of output power and, according to Matsushita, is the largest ever to be cooled with convection techniques.
The tube is aself-contained unit that need only be connected to a power supply. The oscillator tube, magnet, radiator, and filter circuits are in a single package. In operation, the anode and the aluminumfinned radiator are grounded, and 3volts are supplied to the filament. Operating frequency is 2.45 gigahertz.

Matsushita Electric Osaka, Japan [410]

Industrial

Co.,

Electronics IApril 15, 1968

'" -`, J1 Ill

I

1

N -

/

·

al 1

· if, :: 72 i 4.·Nkti

jFD

1 )·.fr `à

. j.\

. · '''·

e

.

/i , ,

' \ ·

"'

/ 1 ,·

'

,/ ·

,

t

(---------

--1

_

": -.,.. ,

1 Z.S1klU ik

Z· it

i

>

11,· 0.

111 ' ''me'

4.
.tt

.· . · i, ....

t.4:

·

g

I

,

e

(2

\ ·.; r::, .,,

fi

k
HAWAII CALLS

.w.,,i.,,;.,eld

ENGINEERS .' . .

4-.r2-

_

announces
THE SMALLEST HIGI- RF POWER
CAPACITORS AVAILABLE!

4,
PEARL HARBOR NAVAL SHIPYARD
needs
Electronic, Electrical, Marine, Mechanical, General, Nuclear Power
Engineers and Naval Architects
STARTING SALARIES: $8,325 to $13,619
depending on experience
Salaries include 15% cost-of-living allowance, which is subject to change.
D Opportunities for professional growth, advancement. D Pleasant living for you and your family. G Pearl Harbor Naval Shipyard, the largest industrial organization in the Pacific, plays avital role in today's nuclear Navy. The activities of the Yard create a broad range of assignments for engineers and naval architects.
Transportation to Hawaii and back provided for employees and their dependents. Household effects will be shipped at government expense. Transportation for home leave provided if employment agreement is renewed after three years. These are career Civil Service positions with regular salary increases, generous benefits, liberal retirement plan. and will be tilled on an Equal Opportunity basis. Send resume of professional experience or Standard Form 57 to:
PEARL HARBOR NAVAL SHIPYARD
(CODE 170) BOX 400, FPO SAN FRANCISCO 96610
Circle 299 on reader service cal a

410A.
o
1 2

Uniceram -- UFP Series
JFD's new Uniceram UFP Series offers the design engineer a broad line of miniaturized high voltage and high current fixed ceramic capacitors for use in RF circuits. These highly stable, small, reliable UFP's have been used up to 200 MHz. They are the ideal 'space-savers' for today's military communications, mobile, commercial broadcast and amateur radio transmitters. UFP1's measure only 35/64" square X 11/64" thick. High Q 'Uniceram' proprietary ceramic material with special internal monolithic construction yields high power handling capabilities per unit volume. Glass encapsulation insures a moisture seal. Wide fine silver ribbon leads are used because of their low inductance and high RF current carrying capabilities.
· Typical ratings are 8 amps, 3,000 volts rms, 12 KVAR for 150 pf UFP1 over the frequency range of 2-30 MHz.
For additional information, write for catalog UNM-UFP-68.

JFE1

"TODAY'S COMPONENTS BUILT FOR TOMORROW'S CHALLENGES"

JED ELECTRONICS CO. / COMPBOrNooEkNlTynS, DNIeVwISYIoOrNk 1151t2h19Av/ePnhuoeneat21622-n3d31S-t1r0e0e0t Offices and subsidiaries in principal cities, world-wide.

"SEE US AT HANNOVER FAIR, HANNOVER, GERMANY"--April 27th--May 5th.

Circle 241 on reader service card

241

60A, 14001/ Controlled Avalanche Thy "stors..

...part of arange covering 1.0 to 62.5A, iooV to
1.4kV in 4different series

Standard types, high temperature types, avalanche types and inverter grades--all readily available from Mullard at competitive prices.

Avalanche Types Rated: 85°C Stud

Here are the details-- Average Current Ratings Up to 6oA Min. Avalanche Voltage Up to 1400V

High Temperature Types

Rated: iIo°C Stud Average Current Ratings Up to 11.5A

Max. Crest Reverse

Working Voltage

Up to 404:DV

Inverter Types Rated: 85°C Stud

Turn off time (up to IoA)
(up to 62.5A) Max. Crest Reverse Working Voltage

to l.L s s
Up to 500V

Standard Types Rated: 85°C Stud

Average Current Ratings Up to 62.5A

Max. Crest Reverse

Working Voltage

Up to i000V

If you are visiting London for the Instruments, Electronics and Automation Exhibition (Olympia, May 13-18) call at the Mullard stand to see these thyristors, and awide range of semiconductors, valves, tubes and components for
industry.
Every designer should have acopy of the Mullard Quick Reference Guide containing information on thyristors, rectifiers, stacks and modules.
Also ask to be put on the mailing list of the Mullard Bulletin--a regular publication which gives details of new components and applications ...the result of extensive research and development programs in the Mullard laboratories in England. Mullard employ i,000 qualified scientists and engineers and have six major plants, with over 3million square feet of floor space.
Write today for information on Mullard thyristors, and for the name of your local Distributor.
Mullard Limited, Mullard House, Torrington Place, London WCI, England.
U.S.A. enquiries to Mullard Inc., ioo Finn Court, Farmingdale, Long Island, New York. 11735 U.S.A. Telephone: (516) 694-8989 Telex: 961455
Mullard

242

Circle 242 on reader service card

Electronics April 15, 1968

New Semiconductors Review

Medium power DTL IC's in the CD2300 family come in 15 circuit types in 14-lead ceramic dual-inline packages. They are directly interchangeable with the 980 and
830 series DTL IC's. Unit price in lots of 1,000 ranges from $2.25 for a dual 4-input expander to $3 for a clocked R-S flip-flop. RCA/Electronic Components, 415 S. Fifth St., Harrison, N.J. 07029. [436]

Complementary pairs of 20 amp
and 10 amp npn and pnp silicon power transistors come in the isolated TO-61 case. Devices offer
breakdown voltages up to 120 y, power dissipation of 50 w at 100°C and gain-bandwidth prodJots of 30 Mhz minimum. Applications include high current amplifiers and bridge circuits. Solitron Devices Inc., 1177 Blue Heron Blvd., Riviera Beach, Fla. [437]

P-channel enhancement mode
MTOS transistor MEM 556 is a high voltage device. It is suited for multiplexing, series and shunt chopping, and commutating. Features include 80-y max. operation and an off-to-on ratio of 2 x
le. The unit shows less than
60% threshold shift with 25-y substrate biasing. General Instrument Corp., 600 W. John St., Hicksville, N.Y. 11802. [438]

Four dual flip-flops (types SN15 9093,-94,-97,-99), 2 hex inverters (SN15 936,-37), and 3 fast-risetime gates (SN15 949,-63,-61) have been added to the series 930/830 DTL IC line. All are available in flatpacks and ceramic and plastic dual in-line packages, and with military or industrial
temperature ratings. Texas Instruments Inc., Box 5621, Dallas
75222. [439]

Silicon transistors 2N5190-95 are 4-amp npn/pnp units that eliminate the need for expensive matching transformers, and can handle up to 35 w of power. Thermopad construction--with a chip-to-heat sink thermal path of 0.030-in.--means low thermal resistance and minimum derating in chassis-mounting uses. Motorola Semiconductor Products Inc., Box 955, Phoenix, Ariz. 85001. [440]

Monolithic IC audio amplifier
PA234 delivers 1 watt of continuous power to either a 16- or 22 -ohm speaker. It requires only 4 external components and is de-
signed to operate from the power supply range of 9 to 25 v. Applications include usage in headphones, phonographs, tape players and tv receivers. General Electric
Co., Electronics Park, Syracuse, N.Y. 13201. [441]

Thyristor SCR 260 is rated at 175 amps half-wave average. Among the major parameters is the forward blocking voltage through
1,500 y steady state, and a 300 v/gsec minimum dv/dt to rated voltage. Surge current rating is
5,000 amps. Price (25-99) is $167 each for the 600-v unit, and $509 for the 1,500-v unit. Westinghouse Electric Corp., Youngwood, Pa. 15697. [442]

Decoder 9307 is a 28-gate circuit that features 4 inputs in 8421 BCD code and prov des active high outputs for a 7-segment numerical display. The chip is sealed in an all-ceramic, 16-pin dual in-line package, with the 16 leads optimally arranged for p-c layouts. Maximum package size is 0.200 x 0.375 x 0.785 in. Fairchild Semiconductor, 313 Fairchild Dr., Mtn. View, Calif. 94041. [443]

New semiconductors

A logical approach to linear IC's

Line receiver and driver operate on single power supply; logic compatibility eliminates need for interface circuitry

Steering clear of the me-too approach to integrated circuits, the National Semiconductor Corp. is fast building areputation as afirstof-a-kind lc maker. Its newest linear circuits to be sold off the shelf --a dual line driver (shown at right) and a dual line receiver--require

asingle power supply and are compatible with transistor-transistor logic, diode-transistor logic, and resistor-transistor logic.
Similar standard circuits now on
the market require two power supplies and external circuitry for interfacing with Tn.., DTL, and Rm.

Electronics IApril 15, 1968

OUT

GROUND

300 -

3.2 k

\
-

A3

34

-

243

· ···································
IT TAKES ALOT OF ADJECTIVES ·
TO DESCRIBE THE SPACE VII..
· · · · · · · · · · · OOOOOOOOOOOOOOO · · OOOOOO · ·
* Adjectives like FAST, ACCURATE, FLEXIBLE, RELIABLE, VERSATILE, ECONOMICAL and MANEUVERABLE. If you doubt for one minute that a humble wiring system analyzer from the middle west can live up to these labels, then try testing this tester for yourself. It was designed and developed (after thorough lab and field testing) especially to meet today's demand for speed, accuracy, versatility and economy. DIT-MCO's Space VII operates on the fully automatic tape input and printout concept. Design and construction are of the highest quality. The "total speed" function of the Space VII gives you faster overall test time because of adaptation and hookup ease, rapid tape feed, speed of test plus speed of fault determination time, scan time, error recording and printout.
WITH THIS ADVANCED SYSTEM you can test up to 2,000 terminations at arate of more than 400 per minute! Electronic engineers who've tried it, call DIT-MCO's Space VII the best intermediate size testing system on the market. We won't disagree.

·· · · ····· DIT

MCO · · · · ·

·

· ·

DIT-MCO INTERNATIONAL

· · · ·

A DIVISION OF XEBEC CORPORATION 5612 BRIGHTON TERRACE
KANSAS CITY, MISSOURI 64130 TELEPHONE (816) 363-6288 TELEX 42-6149

·

IT'S NO WONDER APPROXIMATELY 90% OF ALL MAJOR

·

MANUFACTURERS IN THE COMPUTER AND AEROSPACE IN-

·

DUSTRIES ARE SATISFIED USERS OF DIT-MCO SYSTEMS.

· · s · · · · · · · · · · · · · OOOOOOO · · · · · · · · · · ·

Circle 244 on reader service card

Our little black book has over100,000 phone numbers.

You never had ablack book like it. Over 1,500 pages. And those phone numbers! More than 100,000 telling you who to call/where to go, for the over 4,000 different product categories listed and advertised in the yellow pages of the Electronics Buyers' Guide. It's the industry's one-stop shopping center that lets you find the products and services you need quickly.
You can depend on EBG.
Electronics Buyers' Guide
A McGraw-Hill Market Directed Publication, 330 West 42nd Street, New York, N.Y. 10036

244

.line driver provides
differential output...
Developed by National's director of advanced circuit development, Robert J. Widlar, and design engineer James Kubinec, the ic's are the DM7820 dual line receiver and the DM 7830 dual line driver. Both need only a 5-volt supply. They have built-in overvoltage, shortcircuit, and overshoot protection. Compared with other lc's National Semiconductor's are less susceptible to environmental noise.
Difference counts. Line receivers attenuate a low-level logic signal, riding on a twisted wire pair, to prevent it from being smothered by common-mode voltage. Having a common-emitter input stage after the attenuator network, the receiver then processes the differential signal. The DM7820 differs in that it has a common-base amplifying stage instead of the common emitter, enabling the circuit to operate at asingle, lower bias. Moreover, this leads to greater attenuation of the input.
National Semiconductor's line receiver has wired-on options at the output, termination resistors, and response time control, and accommodates independent channel strobing. Also, the circuit's output section contains a current-source arrangement that doesn't require pnp elements.
The dual line driver feeds twisted pair or coaxial transmission lines, and provides differential outputs for maximum signal-to-noise ratio. The DM7830 has apropagation delay of 60 nanoseconds for a100 ohm-5,000 picofarad load, and has clamp diodes at both the input and output stages to prevent overshoots in the signal.
The military version of DM7820, designed to operate between --55° and +125°C, is priced at $24 in lots of 100; the industrial version, with atemperature range of 0° to 70°C, costs $10 in similar quantities. The military version of the DM7830 is priced at $16, and the industrial version at $8. Both circuits are constructed with a zerovolt threshold level.
National Semiconductor Corp., 2975 San Ysidro Way, Santa Clara, Calif. 95051 [444]
Electronics IApril 15, 1968

(4.
NEW from Cramer

Johnson Introduces Two NEW Components to save space, cut costs!

ADJUST-A -LOI( STOOLS
Adjust to every worker like fine tools!
Cramer Adjust-A-Lok is immediately adjustable to any workers height. Just release the safety stop, and lilt or lower. It can be done just that quick. Since fatigue is a critical factor in efficiency of seated workers, it's just good economics to provide tools that minimize fatigue. With Adjust-A-Lok every worker can find his own most comfortable and efficient level. 6 seat styles and 5 base types provide 30 available models. For more information: write V. P. Sales, Cramer Industries, Inc., 625 Adams, Kansas City, Kansas 66105.

Industrial supplier inquiries invited

ma CRAMER INDUSTRIES INC.
A Subsidiary of US M Oil Co.
Cramer--The leader in style and quality Circle 307 on reader service card

1. Save space with
new, horizontal-mounting, printed circuit, type "U", machinedplate capacitors. Available in various sizes,
with capacity values ranging from 1.2 pf to 24.5 pf, these tiny trim-
mers provide tuning accessibility from edge of board. Printed
circuit boards can be close-spaced, resulting in compact equipment designs. TC--plus
45 15 PPM/°C. "Q"--greater than 1500 at 1 MHz. All metal parts silver plated. Famous
Johnson quality throughout.

announcing the NL-5750 from NATIONAL
Our lowest priced readout tube, $3.95 in 1000 quantity. ·ultra long life ·compact .530" diameter. ·.5" numeral height otwo decimal points standard la flexible leads with standoff spacer for ease
of pc board insertion. "Licensed by Burroughs Corporation"
NATIONAL REQUEST BULETIN
ELECTRONICS, INC. a varian subsidiary
PHONE: (312) 232-4300 · GENEVA. IWNOIS 60134
Circle 308 on reader service card

2. Cut costs with new,
Johnson RIBLOCTM
Tip Jacks that save production line time with press-in design. No mounting hardware to assemble or handle. Simple insertion tool presses Tip Jack into pre-drilled chassis hole for a secure mount that resists loosening and turning. Jack accepts 0.080' tip plug in arecessed, closed-entry type contact. Insulating body is molded of low-loss polyamide. Brass solder terminal is silver-plated and
Tridited. Low cost.

Write today for details and complete specifications on these new Johnson Components!
L

E. F. JOHNSON COMPANY
3046 Tenth Ave. S.W., Waseca, Minnesota 56093 CI)

Circle 245 on reader service card

245

New semiconductors

Diode from Japan crowds the Halls

Device's magnetic sensitivity is 100 times greater; flux determines the resistance

Electronics Engineers
Lockheed Missiles & Space Company is one of the largest electronics firms in the San Francisco bay area. Openings exist in a broad range of specialties and skills. Lockheed, in Sunnyvale, is deeply involved in many exciting, long-range programs in space, on land, and undersea. Such programs as Poseidon, Agena, Polaris, Deep Submergence Rescue Vehicle and advanced land vehicle systems; requiring people in all disciplines, at all levels. And, never before have benefits been more attractive. For more complete information, you are invited to write Mr. R. C. Birdsall, Professional Employment Manager, Post Office
Box 504, Sunnyvale, California 94088. LOCKHEED
Lockheed is an equal opportunity employer.
Circle 309 on reader service card

nmelaf

J0511/11 STOPS IT!
Joslyn Precision Spark Gaps act fast operate precisely at voltage breakdown specified every time no matter how long between transients III will last virtually for the life of your product El arresting capability spans wide current and voltage range
complete protection ...from stock or custom design. Just one of many surge arrester lines. Write or call today for full information on these and other electronic surge protectors.

Joswn

ELECTRONIC SYSTEMS

Division of Joslyn Mfg. and Supply Co.

SANTA BARBARA RESEARCH PARK

P.O. BOX 817 . GOLETA, CALIFORNIA 93017

TELEPHONE (805) 968-3551

44

MITSUMI UHF TV TUNER
Far outrating the FCC and VDE specifications. which are widely prevailing in the World as telecommunication standards. the MITSUMI UHF tuner only radiates spurious signals less than 54 dB below the reference field strength. Material. plating, soldering, as well as the proprietorial circuit design are the technical achievements by MITSUMI based on a long-term fundamental research.

Specifications

Model

Gain (dB)

Noise figure (dB)

Image ratio (dB)

IF rejection (dB)

Frequency stability Outer dimensions (men)

UHF TV tuner UK-A30

--10 mm.

14 max.

30 min.

60 min. Temperature Stability:

--700

at 25

Voltage stability:

65° C

=100 kHzat 11V±1.1V

51 >, 62 5x24.5

MITSUMI .771.11W

MITSUM ELECTRIC COMPANY LIMITED 1056 Noadach , K cue.nach6 KItatama gun, Tokyo. Tel: 489.5333
Manenstrasse 12. Dusseldorf, W Germany. Tel :352705
MITSUMI ELECTRONICS CORPORATION 11 Broadw y, New York 4. N Y. 10004 Tel HA ri KFl5

246

Circle 246 on reader service card

Circle 310 on reader service card

Challenging Hall-effect elements is adiode whose sensitivity to magnetism is 100 times greater--so sen-
sitive that it is affected by the earth's field. The diode is the SN1D, from Japan's Sony Corp.
The smp is atwo-terminal device
that is less than half a centimeter
long. It acts like a junction diode when put in acircuit that isn't ex-
posed to magnetic flux. But when a magnetic field is present, the diode's forward resistance changes-- the direction of the flux determines
whether resistance increases or decreases. Reverse-bias characteristics, however, aren't influenced by a magnetic field.
Bending the path. Sony engi-
neers make the smn by doping the ends of a 3 x 0.6 x 0.4-millimeter
block of germanium. One end is a p+ region and the other n+. The distance between these regions is much larger than their thickness.
Next, a thin layer of an impurity, like nickel or copper, is deposited on the front of the block, forming a region where electrons and holes recombine rapidly. The mean life-
time of these electrons and holes determines the SNID'S forward resistance.
NIagnetic flux passing through

IN REGION p+ REGION

n+ REGION

it VH_ H+

RECOMBINATION REGION

Controlling lifetime. Magnetic field determines diode resistance by bending carrier paths.

Electronics IApril 15, 1968

If you /èould look under the hood
of aTechni-Rite Pen Motor
you would see acomplete
Integrated Circuit Amplifier!

To a maker of specialized recorders -- such as EKG's -- it means:
1. LOWER COST
(no wiring, no circuit boards)
2. EXTREME COMPACTNESS
(Pen Motor with Amplifier is only 2" x23/8"x3")
3. UNPARALLELED RELIABILITY
(integrated circuitry)

Model TM D-25

Write, phone or wire for complete details.
Techni-Rite Industrial Park Warwick, R. I. 02887
Tel. (401) 737-2000 Telex 927725

Let Techni-Rite customize your recorder with this new Pen Motor/Amplifier combination. Select the single channel or multi-channel chart drive which suits your needs; add one or more of the off-the-shelf accessories such as Markers, Rewinders, Power Supplies, or PreAmplifiers and you will have the most modern, lowest cost and most saleable finished product -- whether you make Medical Equipment, Industrial Devices, or what-
have-you.

Model TMD-20

Circle 311 on reader service card
1001 uses for
STEPPER MOTORS

Small -- Positive Grip
MINIATURE
"Locking" Switches

Alco has managed to reduce the size of
the handle on this unusual miniature switch series and still have a perfect grip. Currently available in single and double pole in maintained and momentary locking configurations. Designed for accident-
proof applications. 6 amps @ 125 VAC.

FREE
12 PAGE CATALOG WRITE

ALCOSINITCH
DM OF ALCO ELECTRONIC PRODUCTS INC LAWRENCE. MASS

Because their output is in discrete increments, Cedar stepper motors have many advantages over conventional motors for precise positioning applications. They are bidirectional and have high torque output. They can be run at high stepping rates or as slow as you wish. Because shaft rotation is incremental, damping is not required. Some of the applications for which stepper motors have been used are: replace motor-tachometers in servo systems, control missile ailerons, shutter control on highspeed cameras, open loop positioner in checkout systems, high-speed counter in such applications as rapid firing weapons, replace ultra low-speed dc motors, incremental tape handlers, and digital-to-analog and analog-to-digital conversion equipment. The uses for stepper motors are as unlimited as your imagination. New applications are constantly being discovered. What new use will you next make of stepper motors? Let us know about your ideas; we'll be happy to work with you. Cedar Stepper Motors are available in sizes 5, 8, 11 and 15 in both permanent magnet and variable reluctance types, and with a wide variety of stepping angles. All meet the full requirements of MIL-E-5272. For free booklets on stepper motor application ideas, write or call:

Circle 312 on reader service cerd

CEDAR
ENGINEERING DIVISION

CONTROL DATA
CORPORATION

5806 West 36th Street, Minneapolis 16, Minnesota. Phone 929-1681

Circle 247 on reader service card

247

need know-how?

... four-diode bridge has bilateral response...

Talented, trainable men and women from its 32 colleges and
universities and many vocational schools are one of the reasons
electronic industries come to Iowa... and Iowa industries expand.
Some other important reasons: Major Markets ... Chicago, Detroit, Milwaukee, Minneapolis, Kansas City and St. Louis are all
in Iowa's front yard. Water... from the Mississippi, Missouri and many other Iowa rivers. Transportation ...two navigable
rivers, plus roads, rails and an air-
line network to every conceivable point. Management Time... Iowa executives just naturally have more. They don't waste time commuting daily.
There's more. Fill out the handy coupon... we'll send all the facts. Fast!

r (Conlidential Reply Coupon)
IOWA DEVELOPMENT COMMISSION Dept. 548,250 Jewett Building Des Moines, Iowa 50309

Name Firm Address City

State

Zip

the diode, perpendicular to the broad surfaces of the block, deflect the carriers. When the carriers are pushed toward the recombination region, the lifetime of the electrons
and holes decreases and resistance increases. When the flux direction is reversed, the carriers are steered away from the recombination region and resistance drops.
The competition. The diode's sensitivity is 1 millivolt per milliamp per gauss, compared to 0.001 to 0.01 mv for most Hall elements.
Matsushita Electric Industrial Co. recently introduced athin-film Hall
element with a0.02 mv sensitivity. Despite having poorer detection
ability than the SMD, Hall elements still have a future, according to
George Kiriazides, sales manager for American Aerospace Controls, amaker of Hall elements. He predicts the SMD will open new areas
but won't cut into those markets now dominated by Hall elements. His reasons: Hall elements are thinner, making them more versatile as probes, and they are bilateral, an important consideration in many measuring applications. He also points out that Hall elements have found aplace in analog multipliers that the SMD isn't likely to fill.
Sony, however, is readying the SMD to compete with Hall elements by packaging afour-element bridge that is bilateral.
Heat problems. The SMD'S one drawback is its sensitivity to temperature. For a 6-volt input and 1,000-oersted field strength, the current in the diode will rise parabolically from 0.5 ma to 5 ma
for a0°C to 80°C rise. The maximum power dissipation
of the smo is 50 milliwatts, so, for
some applications pulse operation will be necessary to limit heating.
Possible uses for the SMD are in magnetic detectors, brushless d-c
motors, proximity switches, and noncontact switches. Sony will put the diode in a d-c motor that was designed for a tape recorder the company will introduce in the fall. The diode will be marketed by Sony for $3 in quantity.
Sony Corp., 7-35 Kitashinagawa-ku,
Tokyo, Japan [445]

248

Circle 248 on reader service card

1
, SUPERIOR COAXIAL ATTENUATORS
Prevent

.4,

burnout

The W Model 10 Attenuator has an average power handling capacity of 10-35 W, and 10 kW peak. These medium power attenuators are
commonly used to prevent burnout or overloading of sensitive equipment. They are calibrated at four points over their DC-1.5 GHz frequency range, and can also be
used as standards of attenuation in
loss measurements.

MODEL
10-1 10-2 10-3 10-4 10-5
to 10-20

NOM. ATTEN.
(dB) 1 2 3 4
5-20

POWER INPUT

AV.

PEAK

(W)

(kW)

35

10

18

10

15

10

12

10

10

10

W stainless steel Type N connectors assure maximum life with minimum wear. The custom made film resistors are artificially and stabilized to give maximum stability under peak pulse power and extreme temperature and humidity cycling.
ÏWEINSCHEL and MDaensuifgancetrusrers of Precision Microwave Equipment
ENGINEERING
Gaithersburg, Maryland A ,

Circle 313 on reader service card

FREE BULLETINS
OFFER YOU A CHOICE OF 315 OFF-THE-SHELF FERRITES.

INDIANA Ulan 11111.1111111111

)

9

es

Indiana General has the most complete line of ferrite materials and shapes in the world. Including materials, core sizes, and shapes not available as stardard from any other manufacturer.
In all, we list 15 ferrite materials in 315 standard shapes and sizes including: cup cores; toroids; transformer Ccores; ,cids and strips; E, I, U, and Ccores; the international selies of cup cores, and cross cores.
Chances are, any size, shape, or ferrite material you need is already listed in our Ferramic Materials Bulletins. For your copy, write Mr. K. S. Talbot, Manager of Sales, Indiana General Corporation, Electronics Division/ Ferrites, Keasbey, New Jersey.
INDIANA GENERALE
Circle 314 on rea ier service card

Liteil:Jkr_r
YOU'RE WHISTLING IN THE DARK ..

... if you think that heart disease ard stroke hit only

the other fellow's family. No one is immune. Protect

the hearts you love. For authoitative information, ask your Heart Association. For medical advice see your doctor. Tc

safeguard your family.

HEART sGoIVmEo.r.e.will live

FUND NL

Contributed be ihr Publish,

Electronics IApril 15, 1968

New Design Opportunities With Laminated Plastic Tube Shapes
Why be restricted to the use of round laminated plastic tubes? We make them in a wide variety of inside and outside contours--square, oval, hex, rectangular, and in angles and channels, even multicavity tubes. Wide range of grades, diameters and lengths. Cpmplete fabrication facilities. Write for further information. Synthane Corporation 36 River Road, Oaks, Pa. 19456--or call (215) 666-5011.

SYNTIIANÈ

C

MAI

SI

Laminated Plastic Sheets, Nods,Tubes and Fabricated P'arts

Circle 249cn reader service card

249

The TERMI-BLOK* terminal junction system takes care of all your bussing. Feed-to and feed-thru. Replaces MS terminal strips and screw-type blocks. It's denser, lighter, more versatile, and more reliable. It succeeds where others fail. It's crimpable, insertible and extractible with MS tooling. Automated tooling's available for volume production. For more information write, AMP Inc., Harrisburg, Pa.
*Trademark of AMP Incorporated
FEED-THRU MODULE Contains integral contact receptacles
TERM I-BLOK CONTACT PIN
Machined copper alloy. Rugged and simple design

BOSSES Interlock with adjacent module grooves.
Permit individual module changes BONDED INTERNAL BARRIER Insulates contacts
RIB Holds modules in frame.
Allows fast removal of any module

SEALING MEMBRANE Completely sealed until initial use
FEED-TO CONTACT RECEPTACLE
Combination beryllium copper alloy contact and OFHC copper bus strip
of one-piece construction
RETAINING SPRING Locks cDntact firmly, permits rear extraction for service or change

FEED-TO MODULE Epoxy housing,
silicone rubLer insert
Electronics IApril 15, 1968

MOUNTING FRAME One-piece for feed-to modules.
Mounts in many positions

AdIVII

Ci ,cle 251 on reader service card

251

Cool off microcircuit devices with a choice of four new dissipator/ retainers. Example: with natural convection, atypical microcircuit device dissipates 1.8 watts with case temperature rise of 103°C.

Add IERC's model LBOC2 -61B and you dissipate 5 watts with
the same case temperature rise. Retainer-clip may also be used alone to mount package to conduction plane.

These special dual and quad Therma-Link dissipators permit thermal mating of matched transistors. Therma-Link retainers do exactly as their name says: They provide a thermal link between transistors and the chassis or heat sinks. They are also available with

.060" beryllium oxide washers which have the excellent thermal conductivity of aluminum, are electrically insulative and reduce normal mounting capacitance by 1/2 to 1/3.The washer is brazed to a brass slug or hex stud for mounting.

Need a non-hygroscopic finish with excellent dielectric properties, 50 K megohms insulation resistance and high heat emissivity? Use Insulube 448. It also protects against salt spray and fungus and other adverse environments.

252

Electronics IApril 15, 1968

Tips on cooling off hot semiconductors and microcircuits
Read on. Find out how circuit designers use IERC heat dissipators to protect and improve circuit performance of semiconductors and microcircuits.

Fan Top Dissipators for TO-5 and TO-18 cases add almost nothing to board height. Dcn't
need much room on the board either. Available for both metal and plastic cases. Spring
fingers make installation simple. And Fan Tops cost just pennies.

Help low-to-medium power transistors keep their cool with IERC's stagger-fingered LP's. Available in single or dual mounting for thermal mating of matched transistors. They fit bothT0-5 and TO-18 cases.

Col power transistors and diodes with lightweight HP Senes devices. High heat transfer rate. HP3 displaces only 9 cu.in. and weighs just 1.5 oz. Yet
it dissipates as much heat as many finned extrusions requiring 13.5 cu.in. Two sizes for nesting or
back-to-back use.

Keep TO-66 transistors cool with any of four IERC dissipators. The application shown is a100-volt amplifie: with four LB66B2B's dissipating 8watts per transistor. Exclusive staggered-finger design. Choice of finish: black anodize or Insulubee 448 for positive insulation to 500 watts.

New "...tiniversal" Spade Series for plastic transistors fits all
D-case sizes. Spring clip allows for variation in case diameters. Excellent dissipation lets you boost operating power 33%. Eoth single and dual models as shown.

Got atough one/ Our engineers welcome your inquiry for more specific information. Write us on your company letterhead, please.

lerc

INTERNATIONAL ELECTRONIC RESEAR211 CORPORATION

SEMICONDUCTOR HEAT DISSIPATORS
A corporate division of Dynamics Cormration of America ·135 West Magnolia Blycl.· Burbank, Calif. 91502

Electronics !April 15, 1968

Circle 253 on reader se -vice card

253

CHECK THESE Ada.

New Books

Black-Box Solutions

System Problems
Intronics' solid state MIL-quality function modules offer known performance and cost, plus compact and reliable solutions for system design problems.

.L MULTIPLICATION/ DIVISION/

1 i

-r SQUARE ROOT/SQUARING

i

D M101 -- dc to lkHz. 0.25% accuracy

D D

M102 M201

-- --

dc dc

to to

100Hz, 0.1% accuracy 1MHz. 1% accuracy

i i

Size: (all units) 3.8 Cu. in.

1+ IMPEDANCE BUFFERING
jij FA101 -- 10" ohms in, 0.1 ohms out 0.005% linearity, dc to 200kHz bandwidth Size: 0.8 Cu. in.

+ SAMPLE AND HOLD
FS101 -- 2msec acquisition, 50 nsec aperture time 0.1% accuracy
Size: 1.5 Cu. in.
+ ELECTRONIC SWITCHES
[S101 -- 300 ns Ton. 50 ns Toff, 10'° ohms off impedance, error less than 2mV
Size: 0.8 cu. in. D ES102 -- Buffered switch, 10° ohms
input impedance, 0.1 ohms output impedance
Size: 1.5 Cu. in.

Contact our applications engineering department for your special requirements or mail this ad to:

intronic à4
57 Chapel St..Newton,Mass.02158

Telephone: (617)332-7350 TWX: (710) 335-6835

A welcome jump
Quantum Electronics Amnon Yariv John Wiley & Sons 478 pp. $14.95
As published material on quantum electronics piles up at an alarming rate so, unfortunately, does the jargon. The "in" language makes it difficult and sometimes impossible for the beginner or nonspecialist to comprehend this important field. First-year graduate students--for whom this book is written--and working engineers seeking to break into the field will welcome this volume, which defines all the terminology and uses it consistently to draw together a wealth of fundamental data from awide variety of sources.
By reviewing pertinent areas of quantum mechanics and magnetic resonance early in the text, the author lays the theoretical foundation for the advanced discussions that follow. A senior-undergraduate or first-year graduate course in the subject would help the reader to understand this complex subject, but are not absolutely essential.
The book covers optical resonators and laser oscillation; first the general theory and then the specifics or working systems. Included are solid state, gas, and semiconductor laser types. The author also ties together the many diverse aspects of electro-optics and nonlinear optics, topics that are often given isolated treatment in most literature on the subject. He introduces the electro-optic effect by discussing light propagation in crystals, with and without externally applied electric fields. Then he treats the applications in modulation and light deflection.
A section on nonlinear optics examines optical phenomena that involve energy flow between fields of different frequencies. It includes second harmonic generation, optical parametric oscillation, stimulated Brillouin scattering, and stimulated Raman scattering.
Yariv's volume, now in use at the California Institute of Technology, shows signs of careful organization; the problems at the end of each chapter add to its value for stu-

dents. For others, already active in quantum electronics, the book provides an excellent summary of the technology's fundamentals.
R. T. Denton Bell Telephone Laboratories Murray Hill, N.J.
Turning the heat off
Temperature Control Myer Kutz John Wiley &Sons Inc. 212 pp., $10.95
Second to no other problem faced by designers and users of electronic devices, circuits, and systems, is thermal behavior--the effect temperature variations have on the equipment.
Kutz approaches the subject of controlling the thermal environment from the point of view of the electrical rather than the mechanical engineer. The book is oriented towards applications in computers, guidance and control systems, aerospace equipment, power networks, and modules, not turbines or engines.
Kutz's purpose is to relate the basic empirical and mathematical principles of heat transfer to specific engineering tasks. He covers the mechanisms of heat transfer, the ways of computing the transfer rate in common physical situations, and the thermal properties of basic materials and surfaces. He discusses materials and surfaces, methods of fixing heat-transfer rates, heat exchangers, and thermal-control systems. He also shows how to sense and excite temperature, explains the control of satellite temperatures, and describes the elements of electronic temperaturecontrol systems.
Equipment covered includes electrical resistance elements, power semiconductors, thermostats, thermoelectric devices, and spacecraft systems. The mathematics expressing the relationships is differential and system-derived. This is something EE's should feel comfortable with, and is a long way from the oversimplified, halfexplained algebraic treatments electronics engineers usually find

254

Circle 254 on reader service card

Electronics April 15, 1968

If you supply, serve or compete within the semiconductor field, you can benefit from locating your plant in the Western core of the industry. Here. in Santa Clara County. 14 semiconductor manufacturers prosper -- two to 20 minutes apart. Join the synergistic action sparked by top educational facilities, a business climate that welcomes entrepreneurs, and skilled labor that speaks your language. The $6 billion Western electronics market is at your doorstep! Send for your free copy of amap pinpointing "The Semiconductor Industry in Santa Clara County -.plus eye-opening facts on this technicallyoriented industrial center. Write Ed Beaty, Chamber of Commerce, 499 South Murphy Avenue, Sunnyvale. California 94086.
this is
SEMICONDUCTOR TERRITORY...
PALO ALTO MOUNTAIN VIEW SUNNYVALE
t
SAN JOSE
agood place to locate your business
SUNNYVALE CALIFORNIA
Circle 331 on reader service card

in thermodynamics texts. In fact, the reader needn't even
have a background in thermodynamics to understand the work and apply its principles; Kutz provides all the grounding necessary for the
subject in three chapters on fundamentals.
J.B. Steuer Reimers Electro-Steam Inc.

Unaccustomed as Iam ...

Presenting Technical Ideas
W.A. Mambert John Wiley &Sons 216 pp., $6.95
You don't have to be a technical man to be dull, but it helps. Anyone who has found his eyes closing while aspeaker--all to often an engineer or scientist--drones on, will appreciate Mambert's effort to improve the communication of technical ideas to an audience.
Increasingly, engineers are required to explain complex ideas to their colleagues, to management, to government groups or to non-technically oriented audiences at avariety of seminars and meetings. In his preface, Mambert, who is on the communications staff of the International Business Machines Corp., states the obvious--you can't get ahead in business until you become adept at presenting technical ideas.
About three-quarters of the book is given to practical tips on analyzing the audience, defining the objectives, gathering information, writing the manuscript, preparing notes, using mechanical aids, rehearsing, and handling the unexpected during the delivery of a talk (Someone snoring, perhaps?).
But the reader who takes to heart Mambert's 35 imperatives--which vilI make him abetter communicator of technical ideas, says the author--will discover that he's being asked to restructure his personality. For example, among the fiats issued by Mambert are these: Develop empathy. Become an opportunist. Know thyself. Learn to walk alone. Learn how to break rules. Learn how far you can go. Operate with complete integrity. Be flexible. Be ruthless, sometimes. Love. Develop your sense of humor.
Urging the reader to develop a sense of humor is like telling him to develop sex appeal. Either he

Cool De-Fog Exhaust Circulate
with Sanders MINICLBE® Subminiature Blowers
Missile-bred reliability ...spacesaving one cubic inch size ... 1.25 ounce lightweight ... 2.2 cfm rated output ... 6.3, 26 or 115 vac, 400 cps. Sanders MINICUBE Blower eliminates hot spots around electronic components ... prevents fogging of optical devices. Solves a variety of problems in both military and commercial applications. Write for free literature. Sanders Associates, Inc., Instrument Division, Grenier Field, Manchester, New Hampshire 03103. Phone: (603) 669-4615. TWX: (710) 220-1845.
1" x1" x1"; 2.2 clm nominal; 1.25 ounces; operating temperature range: --55" C to 125° C;typical life: 5000 hours; three models available.
Creating New Directions
Electronics

I ·· ,···1. ,95 ASSOC à·tt S. MC.
SA

NDÉFI1NC.

IN S TRUMENT

DIVISI O N

G.E

F LI NEW r·AMPS..RE

Circle 255 on reader service card

255

11 ,1 111'11111

The Winchester MRAC Series conforms to MIL-C-22857. Hoods, block and contacts are all certified. And only our MRAC connectors can make that claim!
Or provide such adaptability. Easily installed, readily removed contacts are ordered separately. So you can design your own circuitry --at substantial savings in time and labor. And our removable contacts are available in crimp, solder or shielded types. Or wire-wrap. Plus polarizing pins too.
More adaptability. You can intermix power, shielded signal and signal circuits in the same connector. With everything certified to MIL-C22857.
We recommend the MRAC Series for applications such as computers, shipboard equipment, radar and ground support hardware. For details, and prototype quantities, check your local Winchester Distributor. Or write to: Winchester Electronics, Main St. and Hillside Avenue, Oakville, Connecticut 06779.
Specifications: Current rating: Up to 13 amps No. of contacts: 9, 14, 18, 20, 26, 34, 41, 42, 50, 66, 75, 104
Contact Specifications: MIL-C-23216 No. Catalog No. MS17803-16-16 100B -1016P95 MS17803-16-20 100R-1020P95 MS17804-16-16 100B -51016S95 MS17804-16-20 100R-51020S95
WINCHESTER ELECTRONICSM LITTON INDUSTRIES LLJ

New Books

has it or he doesn't. Nonetheless, ensemble value, or by considering

were a reader able to change his one signal at anumber of intervals

behavior, using the author's 35 pre- of time, termed a time value. If

cepts as his guide, he'd develop these two properties are equal, the a calculating self-discipline that function is said to be ergodic. To

could carry him to sanctity or the be ergodic, the function must also

White House. Or both.

be stationary.

A signal which has stationary

Rare bit from Wales

properties but is not completely random--it has some definite prob-

Principles of Automatic Control Martin Healey

ability as to its content--is called astochastic signal. Limiting cases

D. Van Nostrand Co., Inc. 334 pp., $9.00

of stochastic signals are apredictable one like a sine wave, and a

Neophytes in the field of automatic completely random one like white

control should read this book be- noise.

cause of its careful organization of

the standard technology. And experienced engineers should read it Bit-by-bit

because the clarity and brevity of Introduction to Computer the presentation permits new in- Programming and Coding

sights to well-known subjects.

Francis K. Walnut

Healey, who teaches at the Uni- Prentice-Hall Inc. versity College of South Wales and 429 pp., $17.30

Monmouthshire, claims no techni- Walnut's book on the basics of com-

cal originality nor contribution to puter programing is aimed squarely

the field. All he has done is write at those unfamiliar with data proc-

one of the best texts on the subject. essing techniques.

Included are the usual basic sub-

The first few chapters provide

jects on closed-loop control, but background on the principles and

Healey goes beyond the funda- history of data processing, briefly

mentals--with sections on statistics, describe binary and intermediate

nonlinear systems, sampled-data number systems, and summarize

systems, state variable and ma- input-output methods.

trices, computing and simulation.

When he moves on to coding, the

Essential to an understanding of author first defines machine lan-

the advanced--and even the most guage instructions, then introduces

basic--concepts of control, is a the reader to symbolic language.

good grasp of mathematics. If the Brief mention is made of higher-

math involved in specific instances order languages. Practical coding

is complex, Healey provides the is discussed in relation to variable-

necessary material in a clear and word-length and fixed-word-length

succinct fashion.

binary computers. The first machine

The book contains an excellent is typical of small-scale commercial

exposition on statistics in closed- computers, the second of large-

loop control. In just one page of scale scientific units.

text, the reader learns about sta-

Among the subjects covered are

tionary time series, ergodicity, and input-output coding, loops, subrou-

stochastic signals. Here is aprecis tines, serial-search procedures, and

of that page:

sorting. Walnut makes liberal use

A stationary time series is acon- of flow charts to illustrate the vari-

tinuous function which has the ous techniques. Problems--and an-

same long-terni properties at any swers--are presented after each

time. A random noise signal from chapter to review material covered.

an electronic device is stationary

The book will surely be of value

time series; a single transient is to those engineers seeking awork-

not.

ing knowledge of programing, but

Statistical properties of a func- it may also serve as a refresher

tion can be found by considering a course for those practicing the art.

large number of similar signals on

Stephen Strell

any one instant in time, termed an Computer consultant

-4--Circle 256 on reader service card

257

Teltronics 300 Series coherent amplifiers
simplify ultra-low
signal measurements
MODEL 300-A Coherent (lockin) Amplifier reduces complexity and cost of measuring ultra-low level signals
Radio astronomers, medical researchers and those scientists working with paramagnetic resonance or making subtle photometric studies can now simplify those measurements that require instrumentation capable of phase-locking with, identifying and measuring signals buried in the noise up to 50 dB or more.
Teltronics, Inc., has produced fundamentally simple solid state coherent amplifiers with genuinely needed features and lower overall prices.
Modulation Tuning Range: 1.5 Hz to 10 MHz, continuously or with plug-in field-adjustable tuners. Adjustable-Q Filtering: From broadband to high selectivity. Plug-In Preamplifiers: High or low impedance; single or differential inputs with 100 ny fs sensitivity. Internal or External Reference: Reference channel can drive coaxial switch or chopper directly. Price: $1,400 to $2,245 depending on preamplifier and tuning system
Write for Technical Data
Teltronics, Inc.
Box 466, Nashua, New Hampshire 03060 (603) 889-6694 /Subsidiary of Roanwell Corporation

Technical Abstracts

Oceans of data

microwave frequencies with one or

Electronics: the technological key
James C. Elms NASA Electronics Research Center Cambridge, Mass.

more polarizations. Developing these sensors and
finding ways to handle the resulting mass of data will take many years,

Exploring and exploiting earth resources places high demands on electronics technology, specifically

and early hopes may wane before exploratory systems become operational.

for avariety of new sensors and for more efficient data management.

Presented at the IEEE International Convention, New York City, March 18-21.

What electronics specialists will

have to contend with can be seen from atypical earth-resource study Which way to go?

of the future. The assignment is to Trends in the applications of sense, condense, transmit, and an- microcircuits in industrial use

alyze information about conditions of the ocean.
This could be accomplished with

R.F. Eade A.E.I. Automation Ltd.,
Leicester, England

a satellite that would interrogate Designers of industrial instruments

thousands of beacons fixed on the ocean's surface and that would carry some sensors of its own. Each beacon would gather and transmit

and controls now have available a variety of microcircuits, based on different semiconductor technologies, that result in low-cost, off-the-

data on underwater characteristics shelf modules. Prices of standard

to the satellite, which would retransmit all the data to aland-based collecting point. Typical measurements taken on board the satellite would be temperature, color, and surface roughness of a wide ex-
panse of ocean. Technology exists for transmit-
ting information to acentral point, but the required data rate might

integrated circuits have fallen rapidly over the past few years. In 1964 the cost of an lc version of a typical logic package was about 21/2 times that of its discrete-component equivalent; in 1968, the cost of the lc version is about half.
Still, lc's have not made any great impact in the industrial field, except perhaps in computers. But the

create a bandwidth problem. Se- lc is now expected to have major

lecting the pertinent data and com- effects on the business and customs pressing it could help. The main of many electronic systems man-

effort will be to analyze and inter- ufacturers.

pret the data for the benefit of,

First, the percentage of electron-

typically, fishing, shipping, weather ics in the prime cost of a system

prediction, and recreation interests. will increase when Ic's are bought Development of appropriate com- on the outside. Second, economics

puter software seems the most will force a systems maker to use

likely route to rapid and accurate specialized interpretations.
Remote sensing of the ocean's

the standard modules also available to his competitors. Third, when the systems maker believes that acus-

surface presents an even greater tom lc is justified, he will commistechnological challenge. To make sion amanufacturer to design and

accurate temperature measurements from the satellite would require precise radiometers operating

make the device--and will thereafter have to depend on that supplier.

in one or more infrared regions.

Such considerations have led

Color sensing, however, is even some systems companies to build up

more complicated. It will need complete in-house facilities for mi-

scanning and amplitude recording crocircuit production. But this can

in three, if not more, optical or near- be more expensive than most com-

optical regions to determine acolor panies can afford unless they intend

value. A measure of ocean rough- to become lc suppliers. An inter-

ness might best be made by active mediate step is to arrange in-house

radar techniques at one or more facilities for the assembly and test

258

Circle 258 on reader service card

Electronics IApril 15, 1968

Why MARYLAND?

of special devices to meet internal requirements, but to buy such components as diffused chips from specialist manufacturers.
Presented at the Symposium on Applications of Microelectronics, the Institution of Electrical Engineers and the Institution of Electronic and Radio Engineers, University of Birmingham, England, March 27.

Proximity to federal agencies in Washington, D.C. affords the unique advantage of constant personal contact with government officials working with science-oriented industry. Such contact is an increasingly important locational criterion. No other state is as convenient to as many Federal agencies as Maryland. For example, Maryland's major government scientific installations include NASA, AEC, NIH, the National Bureau of Standards, plus some 20 others.
Are there other reasons -why R&D activ ities and science-oriented industries should consider locating in MARYLAND ?
Yes ... emphatically!
The availability of personnel, particularly engineers and scientists, is recognized as a chief criterion governing the location of any science-oriented industry. There are almost 30,000 scientists and over 25,000 engineers living and working in Maryland and the District of Columbia. There are 39 four-year colleges and universities in Maryland and the District of Columbia. Graduate and postdoctoral programs considered most significant to research and science industry are available.
Shouldn't you locate in
MARYLAND?
Get All The Facts.
MARYLAND DEPARTMENT OF ECONOMIC DEVELOPMENT DIVISION E State Office Bldg. ·Annapolis, Md. 21404
Write, Wire Or Phone Collect
Circle 332 on reader service card

All in good time
Satellite multiaccess operation with pcm K.W. Pearson Standard Telecommunications Laboratories Ltd. Harlow, England
A communications satellite that hopes to compete with other transmission methods must be able to talk with several earth stations at essentially the same time. Such a multiaccess operation can separate signals either by frequency or time. Frequency division is more common now, but analysis shows that time-division multiple access using pulse-code modulation could be the better method if faster digital circuits can be developed.
With time division, only one signal is present at any moment and intermodulation among stations can't occur. Input levels from the earth stations to the satellite's transponder don't have to be equal, and the number of stations and number of channels in each can be readily varied.
Disadvantages of apcm system would be that time division would require more radio-frequency power than frequency division, and that most earth stations, which now use frequency or amplitude modulation, would have to be converted to pcm.
In atime-division multiple-access system using pcm, the transmitted information, which would normally occupy an entire time slot, is compressed at the transmitter and expanded in the receiver. To do this, the digital pcm data is stored at the transmitter at its normal bit rate and extracted for transmission at ahigher bit rate. The opposite is done at the receiver, to yield an essentially continuous message.
However, before time-division multiple access using pcm can rival frequency-division multiple access, a high logic speed must be attainable. A satellite with 1,200 channels will need arate of 70 million to 100 million bits a second.

Dependa le Power for Communications and Navigation
Model 4SI250 1P 250 VA
U NITRON STATIC INVERTERS
28VDC to 400Hz
250 VA Sine Wave Output
Lightweight ·High efficiency ·Overload and short-circuit protection · Tested to applicable RFI and environmental specifications ·Stable frequency and voltage regulation.
From Unitron, one of a series of proven, highly reliable solid-state inverters. Stable 400 Hz 1 0 output; low noise and distortion. Operating temperature --55'C to +55°C; altitude to 50,000 ft. Designed to meet electrical requiremer.ts of T.S.O.-C73. For ground support and airborne equipment including transceivers, Doppler navigation, artificial horizons, ADF, omni's. DME, weather radar, transponders and autopilots. Series also includes: 125 & 500 VA, 1 0, and 750 VA, 3 0, inverters. Write today for complete information.
NITRON
Division of Electric Machinery Mfg. Company
1624 N. FIRST ST. GARLAND, TEXAS 75040 (214) 276-8591

Circle 259 on reader service card

259

Compact electronics package?

Technical Abstracts
Logic circuitry for such speeds is already in use experimentally, so one can expect a system accommodating up to 25 earth stations to be built soon.
Presented at the Colloquium on Pulse-Code Modulation, The Institution of Electrical Engineers, Electronics division, London, March 4.

...with asmall size, long life, high output AiResearch fan.
Garrett-AiResearch special purpose fans are individually designed and custom built to deliver more flow and greater pressure rise with aminimum envelope size.
Take atypical AiResearch small size fan: computer-optimized for required performance under all operating environments; our own motor, engineered and manufactured for aperfect match to its fan; and up to 40 percent more airflow than any other ventilating fan of similar input, size, and weight.
Next time you need aventilating fan for avery special airborne or ground electronics enclosure specify AiResearch. Available for high temperature and cryogenic applications, with flow rates and power requirements as specified. AiResearch Manufacturing Division, Torrance Facility, 2525 190th Street, Torrance, California 90509.

FAN PRESSURE RISE IN 14,0 4
,,WATTS 3

POWER, WATTS 50
40

2

30

PRESSURE RISE -.-

1

20

o

20

40

60

80

FAN FLOW, CFM

FSAlPARENECSISAELA.urRPCUHRPOSE EIRRE

Position wanted
The laser gyro Frederick Aronowitz Systems and Research Center Honeywell Inc. Minneapolis, Minn.
Most inertial navigation systems rely heavily on the integrating rate gyroscope to keep track of a vehicle's position in space. A new gyroscope, using the laser and general relativity for its operation, measures rotation in inertial space without the spinning mass found in conventional gyros. Since there is no mass, the laser gyro is unaffected by error-inducing acceleration forces. It also senses higher rates of rotation with greater accuracy, and does so at low cost, low power, and with no special cooling. It has adigital output.
The cavity configuration consists of several mirrors arranged so that energy from the laser point source is built up in the cavity in the form of two waves traveling in opposite directions. These waves can oscillate at different frequencies and amplitudes.
Since the point source is moving relative to inertial space, the light going around the ring-shaped cavity in the direction of rotation must travel a greater distance than the light going in the opposite direction.
The magnitude of this difference depends, among other things, on the cavity's rate of rotation and on the velocity of light. This change in optical path can also be considered to be afrequency difference.
Readout in the laser gyro is obtained by combining the waves to form afringe pattern. The fringes move at the frequency difference rate and, hence, by summing fringe counts the gyro produces adigital output related to position.
Presented a the IEEE International Conven tion, New York City, March 18-21.

260

Circle 260 on reader service card

op
d int Ill
·11 111 1

'INRUSH WSan

unbeatable
test system

Delta's CHARGER is a new concept in

manual testing of your integrated circuits.

Versatility is unbeatable; simply by

changing test heads the CHARGER han-

dles all common devices. A wide temper-

ature range, --65° to +150°C, is equalled

only by much larger, more expensive test-

ing units.

Accuracy is unbeatable; the same test

position for each part insures only

±-0.25°C deviation.

·

Repeatability is unbeatable; identical

electrical parameters are guaranteed be-

cause every integrated circuit is measured from the same test socket.
Continuous throughput is unbeatable in an environmental manual handler; only the CHARGER lets you test an impressive 500 parts per hour!

You'll beat the drum, too, when you use a CHARGER. For the latest information, mail the request card today.

A

/ Delta Design, Inc. /

Delta Design, Inc. 8000 Fletcher Parkway La Mesa, California 92042 Telephone (714) 465-4141
Circle 333 on reader service card

Summit meeting of the international electronic industry

4th International

Exhibition of

4!

Industrial Electronics

in the buildings of the

swiss Industries Fair, Basle

4-8 March 1969

Circle 334 on reader service card

MicroVersaLOGIC
Designed for the toughest applications.
Priced for the easiest.
MicroVersaLOGIC is the complete line of IC logic modules designed for the toughest applications, yet priced lower than other cards.
Built into MicroVersaLOGIC are small size, high reliability, and high performance. They give you assured performance at 5megaHertz, leakproof ceramic DTL chips, and afilter capacitor on each card.
The complete MicroVersaLOGIC line gives you all the ready-made building blocks you need for anything from aregister to an entire digital system, including plug-in power supplies and abroad line of system assemblies and accessories Our 40-page catalog can give you all the facts and possibilities of the MicroVersaLOGIC line, and our price list will prove to you how economically it can be yours. Just write.

One Gift Works Many Wonders
THE UNITED WAY
Electronics April 15, 1968

@varian data machines avarian subsidiary
Formerly Dec'sIon Control, Inc 1590 Monrowa Ave Newport Beach. Gag. TEL (71 4 1646-9371 TWX (910) 596-1358

Circle 261 on reader service card

261

New Literature

on intervolometers
"Our programmable intervalo meters can handle just about any sequencing operation you can think of, where precise timing is required. They're probably the most versatile gadgets of their type available.

The unit shown above, for example, is programmable in both time and mode. We make others where the sequence, too, can be programmed from the face of the unit. You can select the time interval, \Vail i5 c:i2 accuracy, from loo miliseconds to 9.99 seconds, in 0.01 secolid increments. They are simple to operate, and extremely reliable.
These are the first programmable intervalometers, to be specifically designed for militar).- airborne use. They meet the environmental requirements of MIL-STD-810. All the armature and stepping relays are manufactured by us, and conform to MIL-11-6106.
If you write us your needs or simply your name and address, we will mail you our data sheet, unless you are in u real rush, in which case please phone us at (213) 723-3371. Ask for Duane Manning:'

Gicurinini
P.O. Box A-A, Irvine, California 92664 ·(714) 540-9010 Plants in Whittier, Costa Mesa and San Diego
An Independent Company, An Equal Opportunity Employer

262

Circle 262 on reader service card

A-c regulators. Electronic Research Associates, Inc., 67 Sand Park Rd., Cedar Grove, N.J. 07009. Catalog 153 describes a line of solid state, fast-acting a-c regulators. Circle 446 on reader service card
Fixed coaxial attenuators. Weinschel Engineering, Gaithersburg, Md. 20760, offers a data sheet describing series 1 and 2 precision fixed coaxial attenuators available in 10 values from 3 to 80 db. [447]
Bimetal thermostat. Elmwood Sensors Inc., 1655 Elmwood Ave., Cranston, R.I. 02907. Snap-acting, precision bimetal thermostat No. 3450, measuring 0.390 x 0.625 in., is described in bulletin 900. [448]
Flexible printed circuitry. Sanders Associates Inc., Granier Field, Manchester, N. H. 03103. Electrical characteristics, design information and a variety of applications of Flexprint circuitry are described in a 14-page handbook. [449]
Module tester. Radio Engineering Laboratories, 29-01 Borden Ave., Long Island City, N.Y. 11101, has available literature on a module test fixture designed to be used in conjunction with its 2600 series radio relay equipment. [450]
Tunable oscillator. Solid State Electronics Corp., 15321 Rayen St., Sepulveda, Calif. 91343, offers a bulletin describing the model S-300 silicon transistor tunable oscillator. [451]
Laser system. Space Ordnance Systems Inc., 122 Penn St., El Segundo, Calif. 90245, has available a four-page brochure on its Macro-Pak portable neodymium laser system. [452]
Audio connectors. ITT Cannon Electric division of International Telephone and Telegraph Corp., 3208 Humboldt St., Los Angeles 90031, has published catalog AUD-4 covering a series of audio connectors. [453]
Transducers. Consolidated Controls Corp., Bethel, Conn. 06801. A singlesheet bulletin contains complete specifications and fully dimensioned drawings for pressure-to-pulse-rate output transducer type 41PF8. [454]
Head demagnetizer. Ampex Corp., 401 Broadway, Redwood City, Calif. 94063. Description, instructions and specifications of the model HD-16 hand-held head demagnetizer for instrumentation tape recorders are included in data sheet D083. [455]
Pulse height analyzer. Hamner Electronics Co., 1945 E. 97th St., Cleveland, Ohio 44106. Technical bulletin NC-15 describes a time-stable pulse

height analyzer for high-counting-rate applications. [456]
Push-button switches. Nexus Inc., Stamford, Conn. 06902. A six-page folder offers specifications on momentary and push-pull switches for military and commercial applications. [457]
Boron nitrides. The Carborundum Co., Niagara Falls, N.Y. 14300. A 12-page brochure includes detailed application information and tabular and graphical property data for Combat boron nitride solids, powders and coatings. [458]
Microwave packaging. Sage Laboratories Inc., 3 Huron Drive, Natick, Mass. 01760, has available a 40-page system designer's guide to microwave packaging. [459]
Flat ribbon cable. Spectra-Strip Corp., Box 415, Garden Grove, Calif. 92640, has issued a 12-page capabilities brochure and short-form product catalog on flat-ribbon cable and related products. [460]
Heat sink nomograph. Astrodyne Inc., 207 Cambridge St., Burlington, Mass. 01803, has published a nomograph that permits determination of total heat-sink area required for cooling semiconductor devices. [461]
Mass core memory. Ampex Corp., 401 Broadway, Redwood City, Calif. 94063. Specifications, functional block diagram and general description of the 20-million-bit model RM mass core memory are contained in brochure C038. [462]
Sealed capacitors. Film Capacitors Inc., 100 Eighth St., Passaic, N.J. 07055, has issued an engineering bulletin covering type E4 polycarbonate hermetically sealed capacitors. [463]
Circular connectors. Elco Corp., Willow Grove, Pa. 19090. A 12-page catalog describes and illustrates in detail a complete line of circular connectors manufactured to conform to MIL-C26500. [464]
Magnetic core memory. Ampex Corp., 401 Broadway, Redwood City, Calif. 94063. Description, user information and specifications of the model RG magnetic core memory are included in brochure C034. [465]
AID converter. Aero Geo Astro, a division of Aiken Industries Inc., 4810 Calvert Road, College Park, Md. 20740, offers a single-sheet bulletin on the model 801 analog-to-digital converter for economical conversion of analog data to 8 bits of binary data at a 1Mhz word rate. [466]

Electronics April 15, 1968

MICO

NEW MODEL 885 SEVEN RATIO
WIDE-RANGE ENGRAVER

NO. 885

FOR LONG AND MULTI-LINE WORK

New Literature
Low pass filter. Kappa Networks Inc., 165 Roosevelt Ave., Carteret, N.J. 07008. Bulletin 68-1 describes the model 552 series low pass filter designed for p-c board applications. [467]
Display terminal. Transistor Electronics Corp., Box 6191, Minneapolis 55424. Brochure 639 describes the DataScreen display terminal, an input/output crt display system. [468]

Monolithic capacitors

Quartz crystals. Bulova Watch Co., 6120 Woodside Ave., Woodside, N.Y. 11377, has published a 16-page il-
lustrated catalog detailing its complete line of quartz crystal resonators from
1 khz to 150 Mhz. [469]

AMERICAN MADE

·A time-saver for large plate work · Engraves 3" x 19" area in one set-up. · Seven pantograph ratios--from 1:5:1 to 6:1. ·Choice of 3-ball-bearing spindle assemblies for Ye".
3/16" or taper-shank cutters. · HSS, COBALT and Solid Carbide Cutters. ·Single and multi-line copy carriers for holding.
blanks -t.," to 3t..," high. ·Accommodates Mico standard accessories.
Send fer bulletina and pr ce,
MICO INSTRUMENT CO.

77 Trowbridge St.

Cambridge, Mass. 02138

Circle 335 on reader service card

BEST
vacuum

*/

THERMOCOUPLES

Used by prominent instrument manufacturers in the U.S. and abroad for ·true RMS measurement ·transfer standards ·sum and difference multipliers ·low range UHF applications. For example, amatched pair of Best thermocouples contributes to the outstanding accuracy of the 9500A

FLUKE RMS digital voltmeter

If you are designing or manufacturing an AC instrument, why not make it true RMS?
Standard and UHF patterns; high output and square ·law models; matched pairs. See Sec. 5300, EEM. Catalog on request. For free application notes, write on company letterhead to
BEST ELECTRICS DIV.

HARRY LEVINSON CO.

1211 E. Denny Way, Seattle, Wash. 98122 Tel. (206) 323-5100 TWX 910-444-2154

Converter. Airborne Accessories Corp., 1414 Chestnut Ave., Hillside, N.J.
07205. Bulletin PS-20 describes model 1000 millivolt to milliamp converter, a universal temperature transmitter with
an accuracy of -±0.2%. [470]

Coaxial slotted line. Alford Manufacturing Co., 120 Cross St., Winchester, Mass. 01890. Bulletin 703 describes a 3.5-mm coaxial slotted line for the 2to 36-Ghz frequency range. [471]
Indicator lights. Dialight Corp., 60 Stewart Ave., Brooklyn, N.Y. 11237. Catalog L-203 presents a complete line of ultraminiature indicator lights for rear mounting in 3/8 in. clearance hole. [472]
High temperature adhesive. Aremco Products Inc., P.O. Box 145, Briarcliff Manor, N.Y. 10510. Product bulletin 516 deals with Ultra-Temp 516, a ceramic adhesive for use at temperatures up to 4,400°F. [473]
Filters. American Electronic Laboratories Inc., P.O. Box 552PC, Lansdale, Pa. 19446, has available a 16-page brochure delineating its line of standard and custom filters in the frequency range from 2 Mhz to 18 Ghz. [474]
1-f recorder test set. Radio Engineering Laboratories, 29-01 Borden Ave., Long Island City, N.Y. 11101, has released a bulletin covering an adjustable-bandwidth, i-f recorder test set. [475]
Fractional h-p motors. McLean Engineering Laboratories, Princeton, Junction, N.J. 08550. A six-page short form catalog on fractional h-p motors presents the company's line of MIL-Spec and commercial permanent splitcapacitor motors. [476]
Xenon flashtubes. EG&G Inc., 160 Brookline Ave., Boston, Mass. 02215, has issued a catalog containing information and specifications for its expanding line of internally triggered xenon flashtubes. [477]

componen:s and chips shown actual size
If you need microminiature size and the ultimate in reliability--you need SKottie monolithic capacitors.
SKottie monolithics provide the highest capacitance per unit volume available. And monolithic construction makes these capacitors practically immune to their environment. They offer the double protection of fused ceramic plus epoxy or phenobc encapsulation. Both capacitors and chips are available in values ranging from 1.0 pf to 1.0 Mfd and higher in three dielectric materials. The chips are ideally suited for hybrid integrated circuits and can be soldered directly to the substrate. They can be supplied either tinned or untinned and also :n special terminations other than silver. SKottie monolithic capacitors are available molded, dipped, or unencapsulated in both axial and radial lead configurations. Write on your company letterhead for test samples. Ask for bulletin 6801 for more detailed information.
SKOTTIE
ELECTRONICS, INC. Subsidiary of Renwell Industries,Inc. Line St., Archbald, Penna. 18403
Ph: 717-876-1686 TWX: 510-656-2979

Circle 336 on reader service card

Circle 495 on reader service card

263

New Literature

SHIELDED
BLACK BOXES
To package, protect and
SHIELD custom test circuits
(voltage dividers, attenuators, isolation and impedance, networks, etc.). Rugged die-cast aluminum box with aluminum cover, available in 16 different connector combinations. Write for free catalog.

2390

2392

2411

2413

POMONA
ELECTRONICS CO., INC.
1500 E. Ninth Street, Pomona, Calif. 91766

264

Circle 264 on reader service card

Strip chart recorders. Simpson Electric Co., 5200 W. Kinzie St., Chicago, Ill. 60644, has published a four-page
folder giving complete details on the model 2750 precision low-speed strip chart recorders. [478]

H-f antenna systems. Delta Electronics Inc., 4206 Wheeler Ave., Alexandria, Va. 22304. An eight-page short-form catalog describes high power antenna switching matrices with manual and remote control for coaxial and balanced transmission lines. [479]
Inband signaling units. Quindar Electronics Inc., 60 Fadem Road, Springfield, N.J. 07081, has available bulletin 114 on its QT-QR-18 inband signaling units with plug-in adaptors for 600 or 10,000 ohms input/output impedance. [480]

Pain

Integrating microvoltmeter. Doric Scientific Corp., 7969 Engineer Road, San Diego, Calif. 92111. Bulletin D100-E illustrates and describes an automatic integrating microvoltmeter with transducer conditioning for physical and scientific measurement. [481]
Logic assemblies. Cambridge Thermionic Corp., 445 Concord Ave., Cambridge, Mass. 02138, announces a 96-page catalog providing detailed technical data on its complete line of integrated-circuit logic assemblies and accessories. [482]
Varactors. Micro State Electronics, 152 Floral Ave., Murray Hill, N.J. 07974. Bulletin D-103 covers a line of galliumarsenide Micropill varactors for parametric amplifiers, harmonic generators, and switches. [4.83]

If vendors have you in a pinch and another source of
supply will help, turn to the Electronics Buyers' Guide. You'll find all the information you need on over 1,363 sources of power supplies, listed under 11 headings from AC Regulated Power Supplies to Laser Power Supplies.

Coaxial diode limiters. Microwave As-
sociates Inc., Burlington, Mass. 01803. Bulletin 7039 contains technical in-
formation on a series of broadband, fast-recovery, coaxial diode limiters. [484]

Power supply. Quindar Electronics Inc.,
60 Fadem Rd., Springfield, N.J. 07081. Bulletin 138 covers the QP-17 solid state power supply designed to provide 1700 ma at 12 y d-c for supervisory
control, telemetering, and audio tone equipment. [4.85]

Alternator/stator winder. Possis Ma-
chine Corp., 825 Rhode Island Ave.
South, Minneapolis 55426. Two-page bulletin 6712 describes the model
PAW-15A automatic alternator/stator winder. [486]

Motor speed controls. Sterling Electric Motors Inc., 5901 Telegraph Rd., Los
Angeles 90022. A six-page technical bulletin describes new rotating and solid state variable frequency speed
controls for one or more a-c slave motors. [487]

Electronics Buyers' Guide
A McGraw-Hill Market Directed Publication, 330 West 42nd Street, New York, N.Y. 10036

Electronics IApril 15, 1968

atei EMPLOYMENT ern OPPORTUNITIES
The Scientists and Engineers served by Corcoran in the last year have found the difference between "a job" and "the job." · Nationwide. Fee paid. · Please airmail background to.
JOSEPH P. CORCORAN Personnel Consultants
505 BGermantown Pike Lafayette Hill, Pa. 19444 Memè ·rIEEE
CIRCLE 966 ON READER SERVICE CARD

SURPLUS IBM EQUIPMENT
28 page catalog of powers supplies, light & switch panels, semiconductors, test equipment, IC's, optics, etc. GADGETEERS SURPLUS ELECTRONICS, Inc.
5300 Vine St Cincinnati, Ohio 45217
CIRCLE 967 ON READER SERVICE CARD

CIRCLE 968 ON READER SERVICE CARD

RADAR SYSTEMS GROUND AND AIRBORNE. AUTOMATIC

TRACKING ANTENNA SYSTEMS. NIKE AJAX. NIKE HER-

CULES M-33 MS0-1A MPS-19. MPS-9. SCR 584. TPS-112

TP5-28 FAA-ASR-2 AIRBORNE SYSTEMS A.N-84 APN-101

APS-23. APS·27 APS·45 DPN·19. DIGITAL COMPUTERS

'BM 650. IBM 704

A

INVENTORY OY RADAR AND

MICROWAVE EQUIPMENT IN THE WORLD.

RADIO RESEARCH INSTRUMENT CO.

45 WEST 451H ST N Y. 10036

212-JU 6-4691

CIRCLE 969 ON READER SERVICE CARD

Somebody Somewhere,

needs your idle equipment! Reach that buyer quickly and economically thru the
"SEARCHLIGHT SECTION"
The meeting place of Used liquipmeni Buyers and Sellers

Electronics ¡April 15, 1968

ELNGEICTNREOENIRCS
Growth Advancement Salary Recognition
We will provide these ingredients for a strong design background in RF circuitry
an
ELECTRONICS CORPORATION Send your resume to R. S. Lawrence 4323 Arden Drive, El Monte, Calif. 91734 ....an equal opportunity employer....
CIRCLE 970 ON READER SERVICE CARD
Today's brand new ocean opens your brand of engineering career opportunity.

Newport News, world's largest and most advanced shipbuilding company--
involved with all today's revolutionary marine developments--has immediate career openings in all these engineering fields:

Mechanical Engineers Electrical Engineers
Marine Engineers Industrial Engineers
Naval Architects Nuclear Engineers

Civil Engineers Metallurgical Engineers Data Programmers Systems Analysts Chemists
Laboratory Analysts

With an order backlog now over $500,000,000, we're bidding for creative engineers who like challenges and personal responsibility. Write our employment manager, John J. Gaughan. You'll get fast action.

1%Te-vxrport 1%Tevus
Uni POCK con ,..,.t. wr,
An Equal Opportunity Employer

CIRCLE 971 ON READER SERVICE CARD
265

The new AO StereoStar/ZOOM Microscope gives you high resolution, new convenience, superior optics and wide magnification range.
Here are a few of the outstanding advantages that make the new AO® StereoStar/ZOOM Microscope the finest instrument of this type available today: III Widest total magnification range: 3.5-210X 1111 High resolution to meet the most exacting needs · The most convenient zoom control available III Choice of five interchangeable, rotatable zoom power bodies II Crisp, sharp images at all magnifications II Extra large field of view and high eyepoint eyepieces III Wide choice of stands for every purpose II Long working distance I Even illumination over the entire field III Coolest operating illuminator.
See for yourself. Contact your AO Sales Representative for a demonstration, or write for our 24-page, full-color brochure on the newest in stereo microscopes--the AO StereoStar/ZOOM.
'TM Reg., American Optical Co.
v
AO INSTRUMENT COMPANY
SCIENTIFIC INSTRUMENT DIVISION BUFFALO, N.Y. 14215
Formerly Instrument Division of AMERICAN OPTICAL COMPANY
Circle 266 on reader service card

Newsletter from Abroad

France zeroes in on instruments ...

April 15, 1968
The French government has launched the third in its series of moves to strengthen the domestic electronics industry through financial aid and mergers. The latest scheme, Plan Mesure, is designed to help instrument makers.
But industry leaders suspect the government won't back Plan Mesure with muscle. Their estimate is based on the mixed results of the other two drives. There has been considerable support for the computer industry under Plan Calcul, but the components effort, announced ayear ago as Plan Composants, hasn't produced more than afew million dollars in aid.
There's little doubt that instrumentation is asector where the French need help. The vast complex of state-run research organizations buys half of its measuring instruments abroad, almost entirely from the United States. The percentage of foreign-baught instruments is even higher in the private sector.
Plan Mesure will have atough row to hoe. There are more than 50 manufacturers, many of them small, family-owned firms, jealous of their identity. In components, as acomparison, there are five major companies, two of which have merged their component activities.

... as Collins Radio decides to back out

French electronics executives are breathing easier now that the Collins
Radio Co. has shelved for at least five years plans to build an instrument plant in France. Collins says it withdraw because of heavy new investments in the United States and the balance of payments deficit.
Many French industry leaders had viewed Collins' interest, abetted by the Finance Ministry, as arepeat of the great semiconductor assault when U.S. companies flooded the country.

Sanyo calculators shift to the MOS

Development of electronic calculators is getting to be ahabit with the Japanese. The newest arrivals are the Sanyo Electric Co.'s 12-, 14-, and 16-digit models. The firm says it's the first in Japan to use bipolar diodetransistor logic for control and gate functions and metal-oxide-semiconductor shift registers for register and memory functions. Sanyo uses transistors and diodes to interface these two types of circuits and to interface the readout. Other Japanese calculators use cores, delay lines, or bipolar multivibrators where Sanyo uses the MOS shift registers.
The company will start domestic sales later this year but is already shipping export orders. The 12-digit model costs $555, the 14-digit $695, and the 16-digit $830.

Symphonie officials fear U.S. parts ban

French and German managers of the Symphonie communications-satellite project are asking European companies to develop launcher components that would normally be supplied by U.S. firms. Symphonie will compete with the Comsat-controlled system sponsored by the International Telecommunications Satellite Consortium (Intelsat), and European space
officials fcar the U.S. will do everything possible to stall it--including slapping an embargo on American-made electronic components.
The parts in question would be used in the booster's apogee and

Electronics April 15, 1968

267

Newsletter from Abroad

perigee motors. And West Germany's Boelkow combine, contractor for Symphonie's third-stage guidance and control engines, has been trying lately to interest German companies in developing replacements.
Franco-German fears of aparts squeeze have so far been fed only by isolated incidents. A French company says it had to design its own traveling-wave tubes, for example, because the U. S. wouldn't grant export licenses to would-be American suppliers. And while U. S. firms are helping to develop noncommercial European scientific satellites,
none has been permitted to offer even advisory aid to the teams vying for Symphonie contracts.

French seeking to end GE deal

General Electric Co., under President de Gaulle's pressure to get out of the French semiconductor business, is selling its 49% interest in the Societe Europeenne des Semiconducteurs, which it established in 1962 with the Compagnie Francaise Thomson Houston-Hotchkiss Brandt.
At the same time, GE is renegotiating a50-year-old agreement with Thomson Houston in which the French company pays royalties for GE know-how covering abroad area. Lately, however, Thomson Houston has been increasingly dissatisfied. Although both parties feel that the
agreement should be updated, they're miles apart on fees. Some ranking Thomson Houston officials, however, want to get out of
the accord altogether, and GE lawyers are now reviewing the phonebook-size agreement to establish Thomson Houston's withdrawal rights. Chances are the French company would have to pay GE awhopping termination fee.

Raytheon closing Italian tube plant

The 900 workers at the Raytheon-Elsi cathode-ray tube plant near Palermo, Sicily, are being laid off as the plant closes. The company blames
sagging black-and-white set sales in 1967, with no improvement in sight,
and the plant's distance from major set makers, most of which are in the north. The mass layoff has triggered some demonstrations and sympathy strikes.

Swiss, Germans soup up rocket

Switzerland's Contraves AG and West Germany's Dornier System GmhH
are developing amore powerful version of their Zenit research rocket. The new high-altitude rocket will have an operational ceiling of 180 miles and will be capable of carrying a payload of 110 pounds. The highest Zenit can now soar to is 123 miles, with a55-pound payload--but at lower altitudes it can carry up to 280 pounds.
The two firms are eyeing the growing European market for space hardware--the European Space Research Organization alone will need about 200 instrument-carrying rockets over the next five years, West Germany itself about 70.

Addenda
268

The giant Russian exhibit at Rome's electronics show is casting political shadows. With general elections coming up, many Italian politicians view the Soviet effort as an attempt to help the nation's declining but still powerful Communist party. ...The British Decca Navigator Co. has granted ITT the South American manufacturing and marketing rights to its sea and air navigation systems--subjects of apatent dispute between the firms [Electronics, July 10, 1967, p. 189].
Electronics April 15, 1968

ete

NEW TEST DATA FOR CTS INDESTRUCTIBLE CERME SEMI-PRECISION RESISTOR NETWOR

Series 750

2-Pin (1 Resistor)

4-Pin (3 Resisto -s)

6-Pin 1:5 Resistors)

8-Pin (7 Resistors)

Total Module
Load
10,000 Approx. cost

le 0.5 Watts
$>1.W=<

1.0 Wat.3
me
let;g4:e.

1.5 Wa:ts
210
lee"ze

2 0 Watts
26e
-12:31°e·

STANDARD MODULE SPECIFICATIONS FOR ALL SIZES

Resistance Range Resistive Tolerance TC

50 0 to 100K fl *5.0% *300 ppmft

Load Life: 0.1 W per resistor at 70°C, 1000 *0.40% A R max.

hrs. (Over 4,000,000 resistor hours)

*0.20% A R ay.

The data speaks for itself. Examine and judge its value for your applicatior :

Moisture Resistance: .1 rated wattage at *0.50% A R max.

70°C, 90-98% humidity, 1000 hrs.

*0.20% A R ay.

Insulation Resistance: measured wet after moisture resistance test, 200 VDC

500 meg. SI

Extreme Stability and Reliabirity High Power Capability: (Up to 1watt per resistor)
· Space saving--a single modale replaces up to 7 discrete resistors.
· Available in an infinite number of circuit combinations. · Custom-built to your exact requirement. · Ideally suited for cost-saving automatic handling. · Cover coating unaffected by ;olvents.

Thermal Shock: 5cycles. --63°C to +125°C, *0.10% A R max.

no load

*0.03% A R ay.

Short Time Overload: 2.5 times rated volt- *0.25% A R max.

age, 5 sec.

*0.05% A R ay.

*0.10% A R max. Low Temperature Exposure: --63°C, 4 hrs. *0.04% A R ay.

Terminal Strength: 5lb. tensile &compres- *0.10% A R max.

sion, 30 sec.

*0.03% A R ay.

Effect of Scldering: 63/37 solder, 246°C, 2 sec.

*0.10% A R max. *0.05% A R ay.

founded 1896 Re0Lest Cermet Catalog
CTS
OF BERNE, INC.
BERNE, INDIANA

;UM&

11,11.13101AR, OP
CTS C011.01ATION · IL/CHART, INDIANA

Extra cost options 11111.11r

Resistance Range

10 to 49 101K to 1meg.12

Resistance Spread Resistive Tolerance

Over 10 to 1 0.5%, 1%, 2.5%.

TC

±150 ppm/°C

Electronics April 15, 1968

Circle 269 on reader service card

269

We've got op amps like nobody's got op amps.

1. VERY LOW POWER
Vs =,..5 to -±20V R2

The typical dissipation of the NI10001 is but 1.8mW
at Vs = ±15V and 0.6mW at Vs = ±6V. Something of
arecord, no? And further, the mighty NH0001 will deliver over ±10V into a2K load from Vs = ±15V supplies. It's priced at S.l8.0() in 100 to 999 quantities.

2. GENERAL PURPOSE
R2 Vs =,t5 to ±20V

01(1 faithful LM101 is both general purpose and no-sweat in operation. It's short-circuit proof and has
alarge differential input voltage allowance. Moreover, frequency compensation is simple. and there is no
latch-up problem. The price is 5/10.00 in 100 to 999
quantities. (There is also acommercial version, the LM201, priced at 88.80.)

270

Electronics April 15, 1968

3. FULLY COMPENSATED, GENERAL PURPOSE

R2 Vs= ±5V TO -±-20V

The 111101 is kin to the LN1101. The essential difference is that all the required frequency compensation
is inside the package. Current drain is low, even with the output saturated. There is no latch-up when common mode range is exceeded and there's continuous short circuit protection. Price for loo to 999 is
$48.00. The commercial version LH201 is $11.40.

4. HIGH SLEW RATE VOLTAGE FOLLOWER

Vs =

TO

The LM102 voltage follower is the first monolithic amplifier that has combined low input current with
high speed. Slew rate is 10Vbs. The maximum input current is an incredible 10nA. Input currents better than 10nA at 125°C are guaranteed.The price: $30.00 each in 100 to 999 quantities. The --25°C to +85°C LM202 is priced at $12.00, LM302 commercial at 85.40.

5. HIGH OUTPUT CURRENT
Vs , -t-9V TO tI5V R2 RI

RIIIR2 --

200!!200pF _175pF

When we say high output current, we mean high.
The output current on this, the NH0005, is 50mA into a100e load. The price in 100 to 999 quantities
is $45.00. And there's a commercial version, the NH0005C, priced at $22.50.

6. VERY HIGH OUTPUT CURRENT, WITH BUFFER

Vs= :.L-5V TO ±15V

The NH0002 is something else. It has an output cur-

R2

rent of ±300mA into aload of 50Q. The NH0002

buffer is useful ill the loop in all your high current

op amp applications. The price is 820.00 in 100 to

999 quantities.

Electronics IApril 15, 1968

If you'd like tip amps like sAe . Dd. write National Semiconductor

Corporation. 2975 San

a\Santa t:lam. California 95051.

National Semiconductor

Circle 271 on reader service card

271

This new idea ended an era in data recording.

August, 1967, Varian introduced to the world the electrostatic recorder: Statos', first
significant advance in its field in over 10 years. At astroke, it obsoleted all other methods of graphic data recording.

Statos writing heads have up to 100 data styli per 40 mm A simple thing. Statos has no moving parts except the

paper drive. The signal is impressed on paper by a fixed recording

head driven by transistorized preamps and IC digital logic. There is

no arcing, burning or post-fixing of paper, nothing to introduce inertia

into the writing system. Think what this does to operation. And reli-

III

With no pens to adjust, ink to spill, solutions to mix, Statos

sets up in one minute. You have no galvanometers to calibrate or replace, and off-scale

signals have no adverse effect on Statos

whatsoever. And it uses blank paper.

Prints its own chart as it records data.

You change chart formats by switching

rollers, and never have to stock more than one kind of paper.

Typical Statos chart grid roller..

Frequency response and rise time. Compare

>40
a

STATOSRESpONSE--

response curves for pen/thermal recorders with Statos' full-scale amplitude past 1500 Hz. LBOs

HALF SCALE

go higher, of course, but at the expense of accuracy

20

TYPICAL PEN/THERMAL

RECORDER RESPONSE

--a parameter that remains constant in Statos. And

<10

··et

while direct-writing recorders claim about 4ms rise time between 10% and 90% of full scale, we go from

0% to 100`)/0 in 0.2 ms. 0

100 200 300 400 500 1000 2000 3000 4000 5000

FREQUENCY (Hz)

Accuracy, anyone? About the

closest you get to an accuracy spec for adirect-writing recorder is "linearity." Here's

what we say. At any frequency from DC to 1500 Hz, our written record shows the input

signal's value within 1% of full scale, including effects of paper movement, plus non-

linearity, plus hysteresis, plus overshoot... you name it!

Resolution. Statos has adigitized readout, but don't let that fool you. With over 50 styli to the inch, our writing head's pattern is fine enough to show any signal within our frequency limits. And our
50 cm/sec chart speed (250% that of direct-writing recorders) gives you the time-base resolution you need at higher frequencies (for instance, 25 cycles per inch of chart at 500 Hz).

-- ·

_

---- - _ -

--

,

A /

Actual size sine wave recorded on Statos.

One last word: versatile. With IC

digital logic an integral part of its nature, Statos interfaces with computers as real-

time output device (no D/A converter or buffer needed) or input monitor for

either digital or analog data (since it accepts analog and/or BCD inputs).

Its variable recording speed DC motor lets you slave paper speed to external

test equipment. And more, much more. That's why we said all those other

varian recorders are obsolete. They are. Statos did it. Send for data from Sales
Manager, Varian Recorder Division, 611 Hansen Way, Palo Alto, California

94303. International offices in Zug, Switzerland and Sydney, Australia.

recorder division

272

Circle 272 on reader service card

Electronics IApril 15, 1968

Statos. The electrostatic recorder.
Sta:os Ill shown here is an 8-channel analog/digital rack-mounted model complete with preamps. Paper speeds from 0.05 to 50 cm/sec. Also in the Stabs line, but not shown here, are:
Statos I, a 3-channel general purpose recorder, &tier desk-top or rack mounted. Four nodels are available, offering paper speeds to 50 cm/s.90, a variety of input voltage ranges. and various combinations of analog and/or digital inputs.
Statos l, a binary event recorder, either desk-top or rack mounted. Three models are available recording either 50, 75 or 10C simultaneous events at paper speeds to 50 cm/sec.

lower attenuation...

8"diameter flexible HELIAX® coaxial cable

higher power

8" Air dielectric HELIAX coax extends the advantages of flexible cable to very low attenuation or very high power appications that formerly required rigid transmission line.
Corrugated inner and outer copper conductors accommodate thermal expansion without the need for sliding contacts. End connectors mate with 61/8"EIA flanges and lock inner and outer conductors together to eliminate differential expansion.
The continuous, connector free cable assures freedom from the VSWR "spikes" associated with the periodic inner connectors of rigid line in along feeder. Cable assemblies can easily be electrically -ested on the reel to assure your exact system performance. For complete details write Andrew Corporation,10500 West 153rd Szreet, Orland Park, Illinois 60462.

HJ 10-50 HELIAX COAXIAL CABLE

At 30 MHz

At 600 MHz

Attenuation
Aver3ge Power
Othes Power Ratings

.027 dB/100 ft
300 kW
For SSB, 200 kW PEP with antenna VSWR of 3:1 2 Megawatts Peak

.15 dB/100 ft
58 kW
TV transmitter power ratings, 223 kW at Channel 4 and 70 kW at Channel 35

HEtIAX ,crzexiei
ainOIELECTRIC Caen
O

7-68

274

Circle 274 on reader service caro

Electronics 1April 15, 1968

April 15, 1968
Electronics Abroad

Volume 41 Number 8

Great Britain
Track record
Hard hit by the rise of the automobile, British Rail is constantly on the lookout for ways to run its trains more efficiently.
One long-off day, the government-owned railway hopes to have trains without engineers clicking along its tracks. But that will be at the end of the automation line. Meanwhile British Rail researchers have settled already on atechnique --induction coils and binary coding --that they feel will work for a whole range of controls, from simple setups to complex systems.
British Rail expects to start trying out prototypes of its basic hardware before the end of the year on a61 /2 -mile test track. The line's researchers are at work also on a small computer to pair with their building-block units. How fast the mating will come depends in large measure on how well the coils perform in their first trials.
Looped. Basic to the system are groups of coils--up to 32 of them-- connected in series to form atrack loop. The coils will be mounted on the track's ties. On the train, there's a 50-kilohertz oscillator to excite the loop as the train passes over it. There's also areceiver to sense the magnetic fields set up by the coils.
The field direction can be either of two ways, depending on how the coil is connected into the loop. Thus the loop connections establish a 32-bit binary word to feed instructions from the track to the moving train. Binary "O's" and "l's" are sorted out by comparing the phase of the voltage pulses induced in the receiver as it passes over each coil on the track to the phase of the exciting oscillator output. The string of binary bits is then fed to decoding logic to extract the message for display.

Getting there. After it's proved out the fundamental system, British Rail most likely will use it first to signal unchanging information like general speed limits for track sections, spotting coil groups about every half-mile. The 32-bit word will probably include an 8-bit address, a 16-bit message, and an 8bit ending that indicates the distance to the next coil group. This last is necessary because the system will be set up to fail safe. It will automatically put on the brakes if the train passes over asignal group without the engineer acknowledging the message.
The next probable step is adding switchable coil arrays that could feed changing information like free and occupied blocks from the track to the cab.
After that, fast trains will get their small computers. Fed with constants like the train's weight, its length, its running schedule, and its brake power--plus the general speed limits picked up from the coil groups on the track--the computer would continuously display the maximum permissible speed for the train in question. The computer further would compare actual speed with the acceptable one and apply brakes automatically if necessary.

Light brigade
lier Majesty's cost-effectiveness experts figure there's an outlay of $180 every time the Royal Army fires a round of tank ammunition. With the current drive to hold down government spending, that means tank crews get very little live gunnery practice.
Even when live rounds are available, all that tank gunners can shoot at are targets on firing ranges, quite adifferent thing from enemy tanks whose crewmen have ideas of their own about what should--and shouldn't be--blasted into smithereens.
To get around these limitations on battle training, Britain's Ministry of Defense may turn to the laser. Later this month, the ministry very likely will order preproduction versions of amock gunnery system it calls the "direct-fire weapons effects simulator"--essentially an infrared laser projector that "fires" at detectors on "enemy" tanks.
Smoke signals. Solartron Electronic Group Ltd., asubsidiary of Schlumberger Ltd., developed the system in collaboration with the ministry. Details are a military secret, but Solartron has disclosed that the laser "gun"--the company

SPEED
111410
RECEIVER

DECODING LOGIC
Am
PHASE DETECTOR

MESSAGE INDICATOR

f-I> ODFIRETCRTAIIONN

TRANSMITTER

TRACK LOOP /
The connection. Binary code is set in track loop by the way that bit coils are wired into it. The system that British Rail has in mind will handle instructions with up to 32 bits.

Electronics IApril 15, 1968

275

Electronics Abroad

says its infrared output is so low that it's harmless--mounts directly
on the tank barrel. Detectors on the target tank actuate smoke bombs when there's a direct hit. Alterna-
tively, the system can be set up so
that the gunner sees apair of flashing lights in his gunsight rather
than apuff of smoke. For this effect, point-of-impact information is
transmitted over a telemetry link from the target tank to the tank firing the laser.
Several other refinements give gunners an illusion of reality. For
one thing, the straight-line laser path is offset to account for the trajectory of the type of ammunition being simulated. Further, the number of "rounds" available can
be set into the transmitter so that atrigger-happy gunner runs out of shells as he would in battle.
The target apparatus, too, adds reality. It can be adjusted to reflect armor thickness so that a light
"shell" smacking a heavy tank won't register a kill. The target detectors can be arranged to show whether shots are landing ahead of or behind the tank.
Sortie. It's a safe bet that other
armies around the world are working on laser gunnery simulators. But none, apparently, has its system as far along as Solartron has.
A ranking U.S. general, the company claims, rated the laser setup
the most impressive gunnery simulator he'd ever seen. With that encouragement, Solartron will demon-
strate the system to Pentagon officials this fall.

000 buoy-shaped platform, officially
designated the DO-32K, can "fly"
a variety of missions. Put a radar
aboard, they explain, and the platform acts as a spotter of low-flying aircraft. Add atelevision camera and it becomes an observation
station. Install a repeater and it
turns into a communications-network link.
High wire. The tether, Dornier
notes, could make an admirable long-wire antenna for low-fre-
quency broadcasts. And the company's engineers are currently testing a direction-finding system whose antenna elements are
mounted on the rotor blades.
Although the platform was developed under contract to the West
German defense ministry, Dornier hopes to sell it eventually to broadcasters, weather watchers,
and highway traffic controllers. The Kibitzer will make its debut later this month at the Hanover Air Show, and the German armed forces will get their first machines
for tests and evaluation in the fall.
Hold it. The platform, powered by a pneumatically driven twoblade rotor, can climb up to its near 1,000-foot maximum altitude in five minutes. Once on station, it's held
stablized to within 1° by a system based on six gyros--two for each axis. The German subsidiary of the

Tether's end. Capsule can climb to 1,000 feet to serve as lofty lookout.
Perkin-Elmer Corp. supplied the stabilization equipment.
To get unlimited air time for the platform, it's tied to its mobile ground carrier by a fuel hose as well as atether. Fuel tanks on the platform can thus be continually replenished. If the air compressor system that drives the rotors konks out, the blades will free-wheel and the autogyro will prevent a crash landing.

West Germany

Fit to be tied

Designers at Dornier GmbH seem to have crossed ahelicopter with a barrage ballon to come up with their latest flying machine. Called the "Kibitzer," it's atethered platform that uses rotor blades to lift
as much as 120 pounds of electronic hardware to a height of nearly 1,000 feet and keep it there indefinitely.
Dornier engineers say the $25,-

Ready to rise. West German kibitzing capsule for electronic
gear rides its carrier to launching point.

276

Electronics April 15, 1968

Electronics Abroad

Canada

the earlier proposal called for 12 channels for each satellite, the gov-

ernment may decide to slash the

Satellite in sight

number to four, although it has not ruled out the larger spacecraft.

Canada's chances of getting ado- With four channels, Drury claims,

mestic satellite communications the system could be operating by

network on the air by the early 1971. The larger system would take

1970's now seem better than ever. a year longer, the government

As the government released its figures. Each channel could carry

long-awaited White Paper on satel- one television signal or 1,200 tele-

lite communications early in April, phone circuits.

Minister of Industry Charles Drury

Two consortiums, one headed by

indicated there'd be no further Northern Electric Ltd. and the

heel-dragging in Ottawa on the other by RCA Victor Ltd. of Can-

effort to set up a$100-million sys- ada, have been asked to work out

tem. The initial reaction in Wash- detailed proposals for the satellite

ington, whose accord is needed for system and submit them within six

the rockets to launch the satellites, months. Each proposal will be subimplied there'd be little, if any, mitted in two parts, one spelling

opposition.

out what the consortium sees as the

Unless there's an unforeseen hardware for the system, the other

hitch, Drury will put enabling outlining the group's project-man-

legislation for the scheme before agement schemes.

the Canadian Parliament next fall.

Meanwhile, Canadian space offi-

By then, the ruling Liberal Party cials presumably will start nego-

should have settled back into the tiating with the U.S. for launch

governmental groove after choos- vehicles. Washington has been cool

ing anew leader to take over from to Canada's plan for a domestic

retiring Prime Minister Lester Pear- satellite system [Electronics, Sept.

son.

4, 1967, p. 131]. Now that Canadian

High finance. What the govern- intentions to go ahead with the

ment wants is a corporation that project are clear, though, the U.S.

would make it partners with pri- apparently will become more neigh-

vate enterprise. Finding them won't borly. Ottawa insists its domestic

be hard. The country's common intentions don't run counter to the

telecommunications carriers pro- aims of the International Telecom-

posed much the same setup last munications Satellite Consortium

year when they argued that Canada and if it can convince Washington

stake out aspace claim soon [Elec- on that point there should be no

tronics, June 26, 1967, p. 211]. Even problem.

earlier, a group backed by the

Power Corp. of Canada had put in

its bid to finance and operate a

satellite network. Still to be established is the divi-

Soviet Union

sion between government and pri-

vate holdings in the upcoming corporation. R.M. Macintosh, aToron-

Integration drive

to banker, has been tapped to block Wcstern traders who keep asharp

out the financial and management eye on Russian industrial trends

structures. But whatever the share are now convinced that the Soviets allotted for private interests, the are fast nearing mass production

government will retain control over of integrated circuits.

operation.

Although Soviet planners haven't

Dozen? Essentially, the system tipped their hand as to when and

called for in the White Paper is where, an Italian semiconductor

much like that proposed by the specialist on the Moscow scene

common carriers--two satellites maintains that abig pilot produc-

parked in a stationary orbit over tion facility for silicon devices is

the equator at approximately the under construction and scheduled longitude of Winnipeg. But where to start up next year. Another West

European engineer insists, "In two years they'll be in full-scale production of integrated circuits."
Signs. There's plenty of evidence to back up these predictions. The Russians have begun offering semiconductor materials for export. Along with silicon, the Soviets want to sell gallium arsenide, indium antimonide and other hard-to-fabricate materials. An engineer who had achance to test some Russian crystals calls them "comparable to those of Monsanto and other companies' products."
Experienced Westerners see an important clue in the Russians' recent interest in buying a family of computers--the Saab D22 seems to be the one they're eyeing hardest --with ic's. In the past, these traders say, the Soviets have bought single computers for specific uses. If they're negotiating for a whole line, the reasoning goes, it's because they expect to produce their own versions soon.
Countersigns. Although there's fairly general agreement that the Soviets are getting closer to volume ic output, sonic Moscow watchers say there are at least two major problems that still have to be solved.
One is slicing and polishing equipment for semiconductor wafers. According to a prospective buyer of Russian crystals, the export agency that peddles them invariably refuses to slice the doped silicon to buyers' specifications.
The other problem is yields. Although the Russians have been producing transistors since 1960 they apparently are still getting low yields. One Soviet engineer insists the lab he works for has paid the equivalent of $40 for semiconductor devices that cost less than $1 in Western countries.
Japan
New way to skin acat
For many a sidewalk superintendent, the cat skinner rates as the most talented performer on aconstruction job. Perched atop his bull-

Electronics lApril 15, 1968

277

Now in publication!
A Fully Documented Analysis of International Electronics
Four volumes of incisive data--by country-- basic elements in planning and maintaining a position of marketing strength in the international electronics markets.
Updated regularly, information is gathered on the spot and covers all aspects of doing business in electronics in every major electronics market of the world. Tariffs, government policies, exchange controls, credit, trade unions, even the impact of smuggling are covered in these in-depth reports. Send for complete, free information
sensus internatienal

Electronics Abroad

dozer, feet and hands darting over a maze of pedals and levers, a skilled cat skinner is ahighly-paid maestro of earthmoving.
Cat skinning, though, may soon be just another construction job. The Komatsu Manufacturing Co. has developed abulldozer remote control that lets an untrained operator perform like aveteran. The remote operator, in fact, has the advantage of being able to see the front side of the blade. And he can handle jobs with his unmanned bulldozer that would be perilous to a cat skinner.
No man's land. Komatsu's earthmoving automation is getting its first use at a steel mill where hot slag has to be moved around. And like the West German radio-controlled scoop loader delivered earlier this year to the Karlsruhe nuclear research facility [Electronics, Feb. 5, p. 211], the Japanese machine can handle radioactive debris.
Since Komatsu hopes one day to see its radio control become fairly common, it has opted for a lowpower transmitter--about 10 milliwatts--that needs no license. The transmitter operates in the 150megahertz band and has frequency modulation. On the bulldozer, the transmitted commands are picked up by a double superhet receiver.

Handy. The control box, carried on astrap by the operator, doesn't
duplicate the pedals and levers found in conventional bulldozers. Instead, there are two joysticks, one for directing the machine and one for working the blade. Switches control the less frequent functions, such as making throttle settings and turning the engine off and on.
Drive and blade commands are transmitted in atwo-out-of-six frequency code, meaning there can be 15 different combinations. Logic
circuits in the transmitter unit break up the joystick movements into individual commands.
Each joystick in effect controls one transmission channel since the drive and blade signals are transmitted one after the other on a time-shared basis every 50 milliseconds.
Separation. At the receiver, the pairs of modulation tones are separated by six filters and fed to a matrix to recover the command corresponding to the pair. The signals from the matrix control transistor power switches that drive pneumatic valves. They, in turn, control the hydraulic-control valves of the bulldozer.
Komatsu says it can now build the control system for about $8,400, although the first model cost more than twice that much.

Please send me your free, descriptive literature.

Name

Title

Company

Street

City

State

Zip

SENSUS INTERNATIONAL 712 Montgomery Street, San Francisco, Calif. 94111
If you can't wait, call (415) 989-6973

278

Circle 278 on reader service card

Sidelined. Unskilled operator fiddling with joysticks can put bulldozer through its paces like aveteran cat skinner.
Electronics IApril 15, 1968

It adds up
For Japanese desk-calculator makers, it's not amatter of whether to shift to integrated circuits but when. And for the Canon Camera Co., the time is now. The company
will start selling lc calculators in
Japan on May 1. The machines will most likely make their bow in the U.S. sometime this fall.
Canon's move makes it the third major Japanese calculator producer--after the Hayakawa Electric Co. and the Sony Corp.--to get a line of lc models into production. But where Hayakawa counts on Japanese semiconductor suppliers for its kingpin circuits and Sony makes its own, Canon has turned to Texas Instruments.
The Canon calculators, designated the models 163 and 161S, are built around seven types of TI diode-transistor-logic packages. Canon claims the packages are built to its specifications, but one czmnpetitor insists they're the same j:ackages Ti supplies for the Singer Co.'s Friden printing calculator.
On the line. Whether specials
or simply specially tested off-theshelf packages, the ic's Canon is getting from Ti add up to awhopping order. Canon says it plans to produce some 1,500 lc machines a month, and each one will employ 170 Diu, packages; this works out to 250,000 packages amonth.
Along with the ic's, which are used for arithmetic, program, and control operations, the new calculators have discrete transistors to drive the readout displays. And there's a magnetic delay line that
functions as five registers--three for arithmetic and two for memories. Both the displays--cold-cathode tubes--and the delay line are new items in Canon desk calculator
equipment. Comparable. The performance of
the model 163 is said to match that of Hayakawa's CS-32A, also a 16-digit lc calculator. Average add
and subtract time for the Canon machine is 0.01 second; average multiply and divide time is 0.2
second. In Japan, Canon will sell the model 161 for $958, some $14
less than the price Hayakawa lists for its CS-32A. Hayakawa has the

CleTahreest Logic:

Logic modules are built on printed circuit cards. Hole location and front-to-back registration must be vers' accurate for machine assembly. Hand assembly is costly. Plated thru-holes must provide positive continuity. Rejects are costly. Circuit boards for logic modules must be easily solderable. Poor solderability is costly. Printed circuit cards must be delivered in volume tittantitv for large-scale logic module production. Time delays are costly. These are the reasons that Cineh-Graphik-boards are built with such exacting precision. Anything less is too costly.
CINCH-GRAIPHIK

DIVISION

CF

UNITED-CARR

ME MBECI

200 South Turnbull Ganen Road. City cf Induery (Los Angeles), Cald. 91744 ·Phone (213) ED 3-1201. Sales off ces in 33 prInc.bal cMesahrsughout the UMted States, Great Britain, Canada, Australia and West Germany.

CO'iSISTN. OF Cl'iCH MANUFACTURIliG COMPAhl.CP1Cli.G'lAPICA.CINCII-SIMADUOCK,CItiCli.NULINE.UCINIT( (ELECIRONICS) LitD PLAXIAL CABLE DEPT.

Electronics IApril 15, 1968

Circle 279 on reader service card

279

WFIERE
RELIABILITY &fICCURACY
COUNT
INTERNATIONAL PRECISION RADIO CRYSTALS
70 KHz to 160 MHz

F-609

xre ç·

555

.765

H.400-.1
, M11.111011»,

.27, 275

.510
.445

I .040

.-.486

.510

FI-4

.093 dia.--.1 -.--

.250 .040 dia.

HOLDER TYPES
.750

ezzczasuomin,

IN

.765

.765

F-700

765
.050
F-605

.238

·-.486 -··
.125 dia.--1
F-612

.620 I

.192
FM-1

.516 tt

Crystal Types:

(GP) for "General Purpose" applications

(CS) for "Commercial" equipment

(HA) for "High Accuracy" close temperature tolerance requirements

F-13

International Crystals are available from

70 KHz to 160 MHz in a wide variety of

holders.

Crystals for use in military equipment

can be supplied to meet specifications

MIL-C-3098C

WRITE

FOR COMPLETE

CATALOG.

International Crystal Manufacturing Co., Inc.
guarantees every crystal against defective materials
and workmanship for an unlimited time, when used in equipment for which they were specifically made.

INTERNATIONAL

CRYSTAL MFG. CO., INC.
10 NO. LEE · OKLA. CITY. OKLA. 73102

280

Circle 280 on reader service card

Electronics Abroad
edge, though, in size. Its calculator fits into a standard desk drawer; Canon's is alittle too tall for drawer storage.
Canon's 161S, an economy version of the 163, omits many calculation features, such as automatic square root, and contains only one memory. It will sell in Japan for $764.
Italy
Unkind cut
Italians have taken to long-distance direct dialing with gusto. It's fast becoming a national habit to ring up adistant relative from the nearest phone--as long as it's someone else's.
Enough subscribers have complained about unauthorized out-oftown calls that phone companies are taking a hard look at devices that make it require more than a furtive look to place along-distance call. Small locks that put a subscriber's phone off limits for any kind of unauthorized call are on the market, but the country's phone manufacturerers have their eyes on a more sophisticated attachment-- one that cuts off the phone only when an unauthorized out-of-town call is attempted.
SGS-Fairchild, amajor European semiconductor producer [Electronics, Nov. 27, 1967, p. 135], developed the attachment. It's built around a dozen integrated-circuit packages that essentially decode the dial pulses for the first digit of the called number. If the pulses are for a "1," a "9," or a "0"--all direct-dialed long-distance calls start with one of these--the decoding circuit actuates arelay that cuts the phone off the line forthwith--before the complete number can be dialed. Input to the attachment is from a transformer whose primary is wired across the phone's line.
The relay that normally disconnects the phone can be arranged so that the call goes through but an external monitor is alerted. There are also versions where akey can override the cutout relay.
Electronics IApril 15, 1968

Electronics advertisers April 15, 1968

A C DC Electronics

70

Faust/Day, Inc. Adv.

·Acopian Corp.

7

Mort Barish Assoc.

Adams & Westlake Co.

66

Kasper & Assoc., Inc.

Aercom

OAS 14

Grant Adv., Inc.

·Alco Electronic Products, Inc.

247

Marketronics Adv.

Allen-Bradley Co.

41

Fensholt Adv. Agcy.

Allied Van Lines, Inc.

189

Young & Rubicam, Inc.

·AMP, Inc.

250, 251

Garceau, Hallahan & McCullough, Inc.

aAmphenol Corp., Connector Div.

191

Marsteller, Inc.

Andrew Corp.

274

Fensholt Adv., Inc.

AO Instrument Co.

266

Fuller & Smith & Ross, Inc.

Artus Electronique

162

Alain Perraud

Austron, Inc.

283

Don L. Baxter, Div. of

Albert Frank-Guenther Law, Inc.

Babcock Relays Div. of

Babcock Electronics Corp.

174, 175

Jansen Assoc., Inc.

Ballantine Laboratories

218

Lang-Lawrence Adv., Inc.

· Barnstead Subsidiary of

Ritter Pfaudler Corp.

192

Creamer, Trowbridge, Case &

Basford, Inc.

· Beckman Instruments, Inc., Helipot Div. 49

Hixson &Jorgensen, Inc.

· Beckman Instruments

International, S.A.

OAS 12

Hixson &Jo-gensen, Inc.

Bendix Corp.,

Electrical Components Div.

38, 39

MacManus, John & Adams, Inc.

Bendix Corp.,

Semiconductor Products Div.

17

MacManus, John & Adams, Inc.

Bissett-Berman Corp.

213

S FAssociates

· Brush Instruments,

Div. of Clevite Corp.

284

Carr Liggett Adv., Inc.

Buckbee-Mears Co.

152

Midland Assoc., Inc.

· Bulova Watch Co., Electronics Div.

208

Frank Best Co., Inc.

· Burr Brown Research Corp.

186

N.A. Winter Adv. Agcy.

· Bussmann Mfg. Div. of

McGraw Edison Co.

61

Henderson Adv. Co.

CREI, Home Study Division,

of the McGraw·Hill Book Co.

239

Henry J. Kaufman & Associates

Cedar Engineering Div.,

Control Data Corp.

247

Colle & McVoy Adv. Agcy., Inc.

Celanese Corporation of America,

Celanese Plastics Div.

140, 141

West, Weir & Bartel, Inc.

Cerroflex Products,

Cerro Wire and Cable Co.

185

Rochford, Inc.

·Cherry Electrical Products Corp.

24

K & A, Inc.

Chicago Miniature Lamp Works

118

Buti-Roberts Advertising

Cimron Div. of Lear Siegler, Inc.

90

Phillips-Ramsey, Inc.

Cinch Graphik Div. of

United Carr Fastener Co.

279

Reach McClinton & Co.

le Cinch Manufacturing Co.

85

Stral Adv. Co.

·Clifton Precision Products Co.,

Div. of Litton Industries

35

Ivey Adv., Inc.

Colorado State of

Industrial Development Div.

228

Buchen Adv., Inc.

Consolidated Electrodynamics Corp.,

Sub. of Bell & Howell

102, 103

Hixson &Jorgensen, Inc.

Consolidated Vacuum Corp.,

Sub. of Bell & Howell

40

Wolff Assoc., Inc.

Control Products Div. Consolidated

Electrodynamics Corp., a

Bell 8` Howell Co.

166

Watson-Manning, Inc.

Electronics April 15, 1968

·Cornell-Dubilier Electronics

145, 146

raniel & Charles, Inc.

Corning Glass Works

Electronic Div.--Glass Memories

188

Rumrill-Hoyt, Inc.

Corning Glass Works

Electronic Div.--Resistors

142, 143

Rumrill-Hoyt Co., Inc.

Cramer Industries, Inc.

245

Bryan/Donald Adv., Inc.

· C.S.F.

OAS 6

SPI Agency

·CTS Corp.

269

Burton Browne Advertising

Cutler-Hammer, International

OAS 11

Campbell Mithun, Inc.

Cyclo-Tronics, Inc.

54

Bernard J. Hahn & Associates

· Daven, Inc.

60

Weston Assoc., Inc.

Dearborn Electronics, Inc.,

Sprague Electric Co. Div.

10

Harry P. Bridge Co.

Delta Design, Inc.

260

Pacific Publications

Di-Acro Corp., Division of

Houdaille Industries, Inc.

240

Charles E. Brown Adv. Agcy.

Digitran Co., The

230

Smith-Klitten, Inc.

Discon Corp.

62, 63

Al Woodbury, Jr. & Assoc.

Dit-Mco International Division of

Xebec Corp.

244

Martin Fromm & Assoc., Inc.

DoALL Company

154

Howard H. Monk and Assoc., Inc.

Dow Chemical Europe S.A.

OAS 21

MacManus John & Adams S.A.

Duncan Electronics, Inc. Sub. of

Systron Donner Corp.

210

Helme Assoc., Inc.

· DuPont de Nemours Co., Mylar Div.

187

Batten, Barton, Durstine & Osborn, Inc.

Durant Manufacturing Co.

212

Franklin Mautner Adv.

Dynamco Ltd.

OAS 19

Leslie Ingham Assoc. Ltd.

Eastman Kodak Co.,

Technical Corporate Adv.

147

Rumrill-Hoyt, Inc.

E G & G, Inc.

88

Culver Adv., Inc.

E-H Research Laboratories, Inc.

53

Steedman, Cooper and

Busse Advertising

Electronic Assoc., Inc.

82

Ross Roy of New York, Inc.

Electronics Buyers' Guide

264

Plansboard Adv., Inc.

Electronic Engineering Co. of California 236

Jansen Associates

Emerson & Cuming, Inc.

208

Edwin F. Hall

. English Electric Valve Co. Ltd.

OAS 15

Allardyce Palmer, Ltd.

Executone, Inc., Printact Relay Div.

164

J.A. Richards

· Fairchild Instrumentation

83

Faust/Day, Inc.

· Fairchild Semiconductor, Inc.

20, 21

Faust/Day, Inc.

I. Fieldtech, Ltd.

OAS 22

Crane, Norman, Craig & Kummel, Ltd.

Fluke Manufacturing Co., John

15

Bonfield Associates

Garrett Corp.,Airesearch Mfg. Div.

260

J. Walter Thompson Co.

·General Electric Co., Electronic

Components Sales

Operation

150, 151, 224, 225

Robert S. Cragin, Inc.

HGeneral Electric, IGE Export Div.

OAS 7

Robert S. Cragin, Inc.

General Electric, Miniature Lamp Div. 161

Batten, Barton, Durstine & Osborn, Inc.

General Electric Co.,

Semiconductor Products Div. 71, 72, 73

Robert S. Cragin, Inc.

General Electric Co., Specialty Control Div.

233

Robert S. Cragin, Inc.

General Electric Co., Vacuum Products Business Section

86

Doe-Anderson Adv. Agcy., Inc.

General Radio Co.

2nd Cover

Horton, Church & Goff, Inc. Giannini Voltex Co.

262

Everett Assoc.

·Guardian Electric Mfg. Co.

170

K & A Advertising

Hamilton Watch Co.

200

Beaumont, Heller & Sperling, Inc.

Hansen Manufacturing Ca.

172

Keller-Crescent Co.

· Haydon Switch & Instruments, Inc.

198

Reynolds 8, Foster, Inc.

a Hewlett Packard,

Colorado Springs Div.

3rd Cover

Tallant/Yates Adv., Inc.

· Hewlett Packard,

International Import Div.

11

Lennen & Newell, Inc.

a Hewlett Packard, Loveland Div.

226

Tallant/Yates Adv., Inc.

is Hewlett Packard,

F.L. Moseley Co. Div.

2

Lennen 8, Newell, Inc.

a Hewlett Packard, Palo Alto Div.

1

Lennen & Newell, Inc.

HI-G, Inc.

178

Marketing Assistance, Inc.

Honeywell, Computer Control Div.

18, 19

Franklin P. Folts, Inc.

a Honeywell, PMD Div.

221

Batten, Barton, Durstine & Osborn, Inc.

a Honeywell, Test Instruments Div.

107

Campbell Mithun, Inc.

Hughes Aircraft Co.

149

Foote, Cone & Belding

. a Hull Corp.

OAS 18

The Michener Co.

Hysol Corp.

202

Barber & Drullard, Inc.

Indiana General Corp., Ferrites Div.

249

Griswold & Eshleman

Industrial Electronic Engineers

76

Van Der Boom, McCarron, Inc., Adv.

Industrial Exhibitions, Ltd.

235

Walkley Hodgson, Ltd.

Industrial Foundation of Albuquerque 216

Geha-Paskind & Assoc., Inc. INEL

261

Mosse Annoncen A.G.

· Intercontinental Instruments, Inc.

84

J.S. Lanza & Associates

· International Crystal Mfg. Co.

280

Robert V. Freeland & Assoc.

International Electronic

Research Corp.

252, 253

Van Der Boom, McCarron, Inc., Adv.

· Intronics, Inc.

254

Marketing Assistance, Inc.

Iowa Development Commission

248

L.W. Ramsey Adv.

IR C, Inc.

36, 37

Gray 8, Rogers, Inc.

· ITT Jennings Mfg. Co.

139

West, Weir & Bartel, Inc.

ITT Semiconductors Div.

87

Neals & Hickok, Inc.

ITT Wire & Cable

169

West, Weir & Bartel, Inc.

·.IFD Electronics Co., Components Div. Delphi Adv., Inc.
·Johanson Mfg. Co. Josephson, Cuffari & Co.
Johnson Co., E.F. Midland Associates
Joslyn, Inc. Chace Co.

241 238 245 246

· Kepco, Inc.

52

Weiss Advertising

· Lambda Electronics Corp. Michel Cather, inc.
· Lapp Insulator Co.. Wolff Associates

74, 75 204
281

ADC
·······

4t. fmAgRmaPt

· Ledex, Inc. Yeck & Yeck, Inc.
Lenox-Fugle Electronics, Inc. Keyes, Martin & Co.
Levinson Co., Harry Pollock & Loth, Inc.
Litton Industries, Inc., Winchester Electronics Div. West, Weir & Bartel, Inc.
Lockheed Electronics Co. McCann-Erickson, Inc.
Lockheed Missiles & Space Co. McCann-Erickson, Inc.
LTT Promotion-Vente-Publicite

64 283 263
256, 257 211 246
OAS 10

McCoy Electronics Co., Div. of Oak Electro/Netics Corp.

180

Buchen Adv., Inc.

· Machlett Laboratories,

Div. of Raytheon Co.

9

Fuller & Smith & Ross, Inc.

Magnecraft Electric Co.

144

Mills, Fife & MacDonald, Inc.

Mann, David W., Div. of GCA Corp.

217

Culver Adv., Inc.

Marconi Instruments, Ltd.

OAS 4

Taylor Adv., Ltd.

Marconi Co., Ltd. Line Communications

OAS 13

Hampshire House, Ltd.

Marconi Radio Communication

OAS 20

Hampshire House, Ltd.

Maryland Dept. of

Economic Development

259

The Robert Goodman Agcy., Inc.

Metes Corp.

148

Keyes, Martin & Co.

Mico Instrument Co.

263

· Micro Switch Div. of Honeywell

42

Batten, Barton, Durstine & Osborn, Inc.

Minnesota Mining & Mfg. Co.,

Scotchpar Div.

182

Young & Rubicam, Inc.

Mitre Corp.

234

The Bresnick Co.

· Mitsumi Electric Co., Ltd.

246

Sanko Tsushinsha, Ltd.

Molex Products Co.

179

Fensholt Adv., Inc.

Monsanto Co.

222

Foote, Cone & Belding

Motorola Government Electronics Div.

8

Botsford, Constantine & McCarty, Inc.

Motorola Semiconductor

Products, Inc.

12, 13, 43

Lane & Bird Adv., Inc.

Mu!lard, Ltd.

242

Rumrill-Hoyt, Inc.

· National Electronics, Inc. Connor-Sager Assoc.
National Semiconductor Corp. Jay Chiat & Assoc.
· North Atlantic Industries, Inc. Murray Heyert Assoc.
Nytronics, Inc. S.M. Sachs & Assoc., Inc.

245 270, 271
168 220

· Oak Mfg. Co., Div. of Oak

Electro/Netics Corp.

89

Buchen Adv., Inc.

Pastoriza Electronics Co.

172

L.K. Frank Co., Inc.

· Philbrick/Nexus Research

6

Culver Adv., Inc.

Philco-Ford/WDL Div.

219

Hal Lawrence, Inc.

'Philips Eindhoven N.V.

OAS 1

T. A. G. De La Mar

Pomona Electronics Co.

264

Buxton Advertising Agency

· Potter & Brumfield Div.,

American Machine & Foundry Corp. 184

Grant, Schwenck & Baker, Inc.

Radiation, Inc. W.M. Zemp & Assoc., Inc.
Radio Corporation of America Al Paul Lefton Co.
· Raytheon Co., Industrial Components Div. Fuller & Smith & Ross, Inc.
282

51 4th Cover
176

Raytheon Co.,

Microwave & Power Tube Div.

227

Fuller & Smith & Ross, Inc.

Raytheon Semiconductor

181

Botsford, Constantine & McCarty, Inc.

Sanders Assoc., Inc.,

Flexprint Products Div.

214

Chirurg & Cairns, Inc. Sanders Assoc., Inc., Instrument Div.

255

Chirurg & Cairns, Inc.

Schlumberger, Ltd.

OAS 5

Sodipa Contact

-Schlumberger A. C. B.

OAS 9

Industries et Publicite

Schneider, R.T.

A-1 to A-4

Noirclerc Publicite

Scientific Data Systems

44

Doyle, Dane, Bernbach, Inc.

Sensus International

278

John W. Hall

Signetics Corp., Sub.

Corning Glass Works

190

Cunningham & Walsh, Inc.

-Silec Electronique

OAS 8

Publicite y Ch. Lambert

· Siliconix, Inc.

14

Graphics West

Sinclair Radio Labs, Inc.

195

John E. Hayes Co., Inc.

Skottie Electronics

263

SogPiaetrick J. Lahey, Inc.

OAS 24

Etudes et Creations Publicitaire Solartron Electronic

Group, Ltd.

OAS 2, OAS 3

Southern Advertising, Ltd.

Solitron Devices, Inc., Transistor Div.

203

Haselmire Pearson Adv., Inc.

· Sorensen Operation, Raytheon Co.

69

Urrutia & Hayes, Inc.

'Sovcor Electronique

OAS 23

Publi-Service

' S.P. Elettronica

OAS 16

Publicitas SPA

Sprague, Electric Co., The

5, 65

Harry P. Bridge Co.

Sunnyvale, Chamber of Commerce,

Industrial Development Div. Giulie, Smith & Beal, Inc.

255

Sylvania Electric Products, Inc.,

Electronic Components Group

27 to 34

Doyle. Dane, Bernbach, Inc.

Sylvania Electric Products, Inc.,

Parts Div.

199

Doyle, Dane, Bernbach, Inc.

Synthane Corp.

249

Arndt, Preston, Chapin,

Lamb & Keen, Inc.

Synthron Co.

57

De Sales Adv., Inc.

Tally Corp.

153

Bonfield Assoc., Inc.

Technipower

173

S&S Creative Services

Technique et Produits

OAS 17

Ste de Publicite de Films et de

Documentaires

Techni-Rite Electronics

247

Fern/Hanaway, Inc.

· Tektronix, Inc.

156

Hugh Dwight Adv., Inc.

Telonic Engineering Co.

196

Jansen Assoc., Inc.

Telonic Instruments

229

Jansen Assoc., Inc.

· Teltronics, Inc.

258

L.K. Frank Co., Inc.

Tempress Research Co., Inc.

81

Hal Lawrence Inc.

Teradyne, Inc.

22

Quinn & Johnson Adv., Inc.

Test Equipment Corp.

56

Dean & Bain Adv., Inc.

Texas Instruments Incorporated

Components Group

77 to 80

Don L. Baxter, Div. of Albert Frank-

Guenther Law, Inc.

· Texas Instruments Incorporated

Industrial Products Group

232

Robinson-Gerrard

· Times Wire & Cable Div.,

International Silver Co.

201

Mohr & Co., Inc.

· Tracor, Inc.

183

Weekley & Valenti, Inc.

· TRG, Inc., Div of

Control Data Corporation Culver Adv., Inc.

155

Trio Laboratories, Inc. Zam & Kirshner, Inc.
Triplett Electrical Instrument Co.

209 59

Burton Browne Advertising

TWR Electronics, Globe Industries Div. Fuller & Smith & Ross, Inc.
TRW Semiconductors, Inc. Fuller 8, Smith & Ross, Inc.
· Trygon Electronics, Inc. Kameny Assoc., Inc.
Trymetrics Corp. Kameny Assoc., Inc.
· Tung-Sol Div., Wagner Electric Corp. Feeley & Wheeler, Inc.

167 55 58
160 16

Ulano Graphic Arts Supplies, Inc. Lory Roston Associates
Unitron, Div. of Electric Machinery Mfg. Co. Warren Associates
U.S. Naval Ship Missile Systems Henry J. Kaufman Associates

197
259 241

Varian Data Machines

261

Durel Advertising Varian Associates, Recorder Div.

272, 273

Botsford, Constantine & McCarty, Inc.

Varian Associates, Vacuum Div.

177

Botsford, Constantine & McCarty, Inc.

Victoreen Instrument Co., The

165

Palm & Peterson, Inc.

·Weinschel Engineering Co.

248

E.G. White Adv., Inc.

·Weston Instruments, Inc.,

Archbald Div.

205

Arndt, Preston, Chapin, Lamb & Keen,

Inc.

White Electromagnetics

132

E.G. White Adv., Inc.

Classified Advertising
F.J. Eberle, Manager

EMPLOYMENT OPPORTUNITIES 234, 241, 246, 265

Corcoran, J.P.

265

Hoffman Electronics Corp.

265

Newport News Shipbuilding 8, Drydock

265

EQUIPMENT (Used or Surplus New) For Sale

265

Fishman Philip

265

Gadgeteeers Surplus Electronics Inc.

265

Radio Research Instrument Co.

265

· For more information on complete product line see advertisement in the latest Electronics Buyer's Guide Advertisers in Overseas Advertising Section following newsletter from abroad

Electronics Buyers' Guide
George F. Werner, General Manager [212] 971-2310 Ray Smyth, Eastern Regional Manager [212] 971-6538 Regina Hera, Directory Manager [212] 971-2544 Thomas M. Egan, Production Manager [212] 971-3140
Circulation and Research
Milton Drake, Manager [212] 971-3485 Isaaca Siegel, Assistant Circulation Manager [212] 971-6057 David Strassler, Assistant Research Manager [212] 971-6058 Chloe D. Glover, Research Associate [212] 971-6057
Electronics IApril 15, 1968

Advertising Sales Staff
Frank E. LeBeau [212] 971-6464 Advertising Sales Manager
Wallis Clarke [212] 971-2187 Assistant to sales manager Donald J. Austermann [212] 971-3139 Promotion Manager
Warren H. Gardner [215] LO 8-6161 Eastern Advertising Sales Manager
Atlanta, Ga. 30309: Michael H. Miller, 1375 Peachtree St., N.E. [404] 892-2868 Boston, Mass. 02116: William S. Hodgkinson McGraw-Hill Building, Copley Square [617] CO 2-1160 Cleveland, Ohio 44113: William J. Boyle, 55 Public Square, [216] SU 1-7000 New York, N.Y. 10036 500 Fifth Avenue Donald R. Furth [212] 971-3615 James R. Pierce [212] 971-3616 John A. Garland [212] 971-3617 Philadelphia, Pa. 19103: Jeffrey M. Preston Warren H. Gardner, 6 Penn Center Plaza, [215] LO 8-6161 Pittsburgh, Pa. 15222: Warren H. Gardner, 4 Gateway Center, [412] 391-1314 Rochester, N.Y. 14534: William J. Boyle, 9 Greylock Ridge, Pittsford, N.Y. 17161 586-5040
J. Bradley MacKimm [312] MO 4-5:300 Midwest Advertising Sales Manager Chicago, Ill. 60611: Robert M. Denmead, J. Bradley MacKimm, Ralph Hanning, 645 North Michigan Avenue, [312] MO 4-5800 Dallas, Texas 75201: Richard P. Poole, 1800 Republic National Bank Tower, [214] RI 7-9721 Houston, Texas 77002: Kenneth George, 2270 Humble Bldg., [713] CA 4-8381 Detroit, Michigan 48226: Ralph Hanning 856 Penobscot Building [313] 962-1793 Minneapolis, Minn. 55402: J. Bradley MacKimm, 1104 Northstar Center [612] 332-7425 St. Louis, Mo. 63105: Robert M. Denmead The Clayton Tower, 7751·Carondelet Ave. [314] PA 5-7285
James T. Hauptli [415] DO 2-4600 Western Advertising Sales Manager Denver, Colo, 80202: Joseph C. Page, David M. Watson, Tower Bldg., 1700 Broadway 1303] 255-5484 Los Angeles, Calif. 90017: Ian C. Hill, John G. Zisch, 1125 W. 6th St., [213] HU 2-5450 Portland, Ore. 97204: James T. Hauptli, 218 Mohawk Building, 222 S.W. Morrison Street, Phone [503] 223-5118 San Francisco, Calif. 94111: James T. Hauptli, 255 California Street, [415] DO 2-4600
Pierre Braude Tel: 225 85 88 European Director 88-90 Avenue Des Champs-Elysees, Paris 8
Brian Bowes Tel. Hyde Park 1451
United Kingdom and Scandinavia 34 Dover Street, London W1 Milan: Robert Seidel 1via Baracchini Phone: 86-90-656 Frankfurt/Main: Hans Haller Elsa-Brandstroem Str. 2 Phone: 72 01 81 Geneva: 1, rue du Temple Phone: 31 95 60
Tokyo: George E. Olcott, 1, Kotohiracho Shiba, Minato-Ku [502] 0656 Osaka: Ryoji Kobayashi 163, Umegae-cho Kita-ku [362] 8771
Business Department
Wallace C. Carmichael, Manager [212] 971-3191 Stephen R. Weiss, Production Manager [212] 971-2044 Thomas M. Egan, Assistant Production Manager [212] 971-3140 Dorothy Carmesin, Contracts and Billings [212] 971-2908 Frances Vallone, Reader Service Manager [212] 971-2865
Electronics IApril 15, 1968

NEW FROM AUSTRON

TF0-22 Series

FMC Series

Tuning-Fork Oscillators

Your low-frequency control requirements can be met most economically with Austron's TF0-22, designed to drive latest TTL or DTL micrologic devices. Features include wide temperature range and frequency range from 360 Hz to 10 kHz. The PMC is a rugged control device meeting severe shock and vibration MIL-SPEC requirements. Frequency range is from 2 kHz to 10 kHz. Write for details on Austron's complete oscillator line.

INC. 10214 NORTH INTERREGIONAL HIGHWAY, AUSTIN, TEXAS 78753 TELEPHONE (512)454-2581
Circle 281 on reader service card

nu smallest axial shielded inductor available the "NANO-RED"

0.250 .1,0.010
1 Ile

#2é4

olooi ,0,0

13TOP min

ACTUAL SIZE

Range: 0.10ph to 1,000ph in 49 stock values Size: 1/10 dia. by 14 lg. Inductance Tolerancè: ±10%

This new "NANO-RED" offers the highest inductance to size ratio available in an axial shielded inductor. Exceptional "0" and self-resonance characteristcs. Max. coupling 2% units side by side. Non-flammable envelope. Designed to MIL-C-15305C. Operating
temperature --55°C to 125°C.

Other Lenox-Fugle Subminiature Shielded Inductors:

02.
0.125 007

) MICRO-RED
I I TYPmm

The "Micro-Red" is ashielded inductor that offers the largest inductance range in its size: 0.10ph to 10,0000. Q to L ratio unsurpassed, with excellent distributed capacity. Inductance tolerance ±-10%. Designed lo MIL-C-15305C. Stocked

#24 0 157.. 007

0375

in 61 predesigned values.

-.1DM- INI-- RED The "Mini-Red" offers the highest "Q" to "L" ratio available

I3 TVP n

over inductance range 0.10ph to 100,000ph in its size. Induct-

0. 50

ance tolerance ±10% measured per MIL-C-15305C. Stocked

.BELL TO BtLL DIMENSIONS

in 73 predesigned values.

#24/ M22 t

t, 0 395 ' 020
l.....-1

DURA-RED The "Dura-Red" is designed to MS-90537 with inductance range 0lOph to 100,000ph with tolerance ±10%. Stocked in 73

s

oil 17/16 C3/16 predesigned values.

0 157 5 010

Data Sheets: write or phone
LENOX-FUGLE ELECTRONICS, INC.

100 Sylvania Place, South Plainfield, N. J. 07080
Telephone: Code 201, 756-1164

Circle 283 on reader service card

283

meek *rent
101

o gm*

olubri ,

sonetv·ty

efftetlivity

*

25

125

sons ,11····11,

n,rnibec
.enetivity

mark twormt DerfaltIv1fY

CLEVITE ....rus,, MARK 2(30

L

1

1

I

3

GL.nied

4

I

I

5

I

1

I

,,,,51111,111,1,11 ,1 1a ,1211111111,11111111,15.11011 .
1·111111111 1/10111flit ,- 1, e,111 11111,1141111
',1i1/1!111,,,iiiif it:. ···., ;*:,.1.11:111111111111,,, ·.1 11,:1,1;!":1·1111.:11: ·

$4500 is alot of money for aportable multi-channel recorder. Or is it?

It depends on what portable recorder you're talking
about. Take that new Mark 260 up there. It costs $4500. But it's a bargain. It has six analog channels, and four event channels. (That's more than you get with recorders twice as big ...and a lot more expensive). It has the famous Brush patented pressurized ink-writing system. (No spatter, no puddles ... crisp clear smudge-proof traces at any writing speed) ...rugged, reliable solid state electronics. (Bounce it around a bit. We don't mind, and it doesn't either)
. . .8 pushbutton chart speeds (easy as changing stations on your radio) ...99% accuracy (which is as good as our best, the Mark 200. And that's a Circle 284 on reader service card

good deal better than anything else on the market) . . .frequency response out to 150 Hz at usable amplitudes. Measurement range of 1 millivolt to 500 volts (covers anything you're likely to handle). At $4500 the new Mark 260 by Brush is the recorder bargain of the year. A full-color brochure is yours for the asking. Write: Clevite Corporation, Brush Instruments Division, 3773 Perkins, Cleveland, Ohio 44114.
CLEVITE BRUSH

New All-Solid-State hp 1200 Scope System Sets New Standards of Performance for Your dc-500 kHz Measurements

Now you can upgrade your low frequency measurements with the new hp 1200 scope system for better performance, greater sensitivity and improved accuracy in the dc to 500 kHz range.
The hp 1200 scope system has an all-new design from the inside out to provide all-solid-state reliability and stability. Drift has essentially been eliminated to al low accu rate measurements--even in the 10011V dc area. Controls on the front panel have been grouped to give faster measurements, quicker set-up, direct dial readout even when using the magnifier.
Choose from four models to get single or dual trace 100 IÀV/cm sensitivity, or single or dual trace 5 mV/cm sensitivity. The 100 1.¡V scopes have 17 calibrated ranges in 1-2-5 sequence with vernier for continual adjustment between ranges. (The 5 mV scopes have 12 calibrated ranges.) All four

models have large 8 x 10 cm internal graticule CRT's, singje-ended or differential input on all ranges, complete triggering versatility, external horizontal input. dc-coupled Z-axis, beam-finder --many of the features you normally associate only with h,gh frequency scopes.
All four models are available as lightweight (< 25 pounds) cabinet or 514" high rack mounts. Power consumption of 33 watts eliminates need for cooling fans.
For details on how you can increase your measurement confidence and your measurement accuracy in the low frequency range, contact your nearest hp field engineer. Ask him about the new hp 1200 scope system. Or, write to HewlettPackard, F'alo Alto, California 94304. In Europe: 54 Route des Acacias, Geneva.
Circle 901 on reader service card

1200A/AR*

Number of ChEnnels

Aide

2

Maximum Vertical Sensitivi

100 DV/cm

Common Mode Rejection (Differential)

100 dB

X-Y Capability

Identical Amplifiers (17 ranges)

Price

$990

AR indicates 51/4"rack mount model

1202A/AR*
100 pV/cm
100 dB 17 vertical vs. 4horizontal ranges
$790

1205A ,AR
5mV/cm
50 dB Identical Amplifiers
(12 ranges) $875

1206A/AR*
5mV/cm
50 dB 12 vertical vs. 4horizontal ranges
$715

HEWLETT hp PACKARD
OSCILLOSCOPE SYSTEMS

RCA hard-tube modulators... for nanosecond service

Now, nanosecond switching time, low inductance, and low capacitance come naturally for L-, C-, X-, and Sband radar with RCA-4630 and 4634 Cermolox® tubes. Representative of RCA's capability in hard-tube modulator service, these conduction-cooled, beam power tubes are especially suitable for high-package-density airborne applications where usec modulation of reactive loads is required at high duty factors. Cermolox construction achieves a new high in tight characteristic control for ultra-reliable systems.
RCA-4630 is rated for 17 kV DC plate voltage. Its reliable matrix cathode permits a peak plate current rating of 40.0 amperes at aduty factor of 12.5 per cent and apulse duration of 2usec. RCA-4634 is rated for 7000 volts. Its peak plate current rating ranges from 8.0 amperes at 2 usec pulse length and 0.05 per cent duty factor to 0.6 amperes at a DC level.
Your RCA Representative can tell you more about these hard-tube modulators and how their characteristics and cooling methods can be tailored to your space configurations. Technical data from Commercial Engineering, Section D-319-Q, RCA Electronic Components, Harrison, New Jersey 07029. Also available from your RCA Industrial Tube Distributor.
RCA

RCA-4630 and 4634 -are icaIf th? compact, rugged units aai able fron .RCA for use as hard-tube rodulators..


PDF Compressor 8.2.02.12 Foxit FXPDFA 1.2