A_8903E A 8903E

Errata

Title & Document Type:

Manual Part Number:

Revision Date:

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For example, model number HP8648A is now model number Agilent 8648A.

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8903E Operation & Calibration

Manual

08903-90053

July 1985

HP

8903E

Distortion Analyzer

Operation and

Calibration Manual

a

e

a

e

0

e

a

e

0

a

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a

:. .e.

.....

...e

00..

Ag

i

I

en

t

Techno

Io

g

i

es

.....

. . ..

HP

8903E

DISTORTION

ANALYZER

(Including

Option

001)

SERIAL

NUMBERS

This manual applies directly to instruments with

serial numbers prefixed

2507A

and

2516A.

For additional important information about serial

numbers, see

Instruments Covered

by

Manual

in

Section

1.

First Edition

@HEWLET-PACKARD COMPANY

1985

EAST 24001 MISSION AVENUE, TAF C-34, SPOKANE, WASHINGTON,

USA.,

99220

Operation and Calibration Manual Part

No.

08903-90053

Operation and Calibration Manual Microfiche Part

No.

90069

Printed:

JULY 1985

1

Regulatory

Information

(Updated

March

1999)

1

Regulatory Information

(Updated

March

1999)

Safety Considerations

GENERAL

This product and related documentation must be reviewed for familiarization with safety

markings and instructions before operation.

This product has been designed and tested in accordance with

IEC

Pubhation

101

0,

"Safety Requirements for Electronic Measuring Apparatus," and has been supplied in a

safe condition. This instruction documentation contains information and warnings which

must be followed by the user to ensure safe operation and

to

maintain the product in a safe

condition.

SAFETY

EARTH GROUND

A

uninterruptible safety earth ground must be provided from the main power source

to

the

product input wiring terminals, power cord, or supplied power cord set.

SAFETY

SYMBOLS

A

Indicates instrument

damage

can occur if indicated operating limits are exceeded.

Indicates hazardous voltages.

Indicates earth (ground) terminal

WARNING

A

WARNING

note denotes a hazard. It calls attention to a procedure,

practice, or the like, which, if not correctly performed or adhered to,

could result in personal

injury.

Do

not proceed beyond a

WARNING

sign until the indicated conditions are

fulls

understood and met.

CAUTION

A CAUTION note denotes a hazard.

It

calls attention to an operation

procedure, practice, or the like, which, if not correctly performed or adhered

to, could result in damage

to

or

destruction

of

part

or

all of the product.

Do

not proceed beyond an CAUTION note until the indicated conditions are fully

understood and met.

2

Chapter

1

Regulatory Information (Updated

March

1999)

Safety Considerations for this Instrument

WARNING

This product is a Safety Class

I

instrument (provided with a

protective earthing ground incorporated in the

power

cord). The

mains plug shall only be inserted in a socket outlet provided with a

protective earth contact. Any interruption of the protective

conductor inside

or

outside of the product

is

likely to make the

product dangerous. Intentional interruption

is

prohibited.

Whenever

it

is

likely that the protection has been impaired, the

instrument must be made inoperative and be secured against any

unintended operation.

If

this instrument is to be energized

via

an auto transformer (for

voltage reduction), make sure the common terminal is connected

to

the earth terminal

of

the power source.

If

this product

is

not used

as

specified, the protection provided by

the equipment could be impaired. This product must be used in a

normal condition (in which all means for protection are intact) only.

No

operator serviceable parts in this product. Refer servicing to

qualified personnel. To prevent electrical shock, do not remove

covers.

Servicing instructions are for use by qualified personnel only.

To

avoid electrical shock, do not perform any servicing unless you are

qualified to do

so.

The opening of covers

or

removal of parts

is

likely to expose

dangerous voltages. Disconnect the product from

all

voltage sources

while

it

is

being opened.

The power cord is connected to internal capacitors that

my

remain

live

for

5

seconds after disconnecting the plug from its power supply.

For Continued protection against fire hazard, replace the line fuse(s)

only with

250

V

fuse(s)

or

the same current rating and type

(for

example, normal blow

or

time delay). Do not use repaired fuses or

short circuited fuseholders.

Always use the three-prong ac power cord supplied with this

product. Failure to ensure adequate earth grounding by not using

this cord may cause product damage.

This product

is

designed

for

use in Installation Category

I1

and

Pollution Degree

2

per

IEC

1010

and

IEC

664

respectively.

FOR

INDOOR

USE

ONLY.

This product has autoranging line voltage input, be sure the supply

voltage

is

within the specified range.

Chapter

1 3

Regulatory Information

(Updated

March

1999)

To

prevent electrical shock, disconnect instrument

from

mains (line)

before cleaning, Use a dry cloth or

one

slightly dampened with water

to clean the external case

parts.

Do

not attempt

to

clean internally.

Ventilation Requirements: When installing the product in a cabinet,

the convection into and out

of

the product must not be restricted.

The ambient temperature (outside the cabinet) must be less than the

maximum operating temperature of the product by

4"

C

for every

100

watts dissipated in the cabinet. If the total power dissipated in the

cabinet

is

greater than

800

watts, then forced convection must be

used.

Product Markings

CE

-

the CE mark

is a

registered trademark

of

the European Community.

A

CE mark

accompanied

by

a

year indicated the year the design was proven.

CSA

-

the

CSA

mark

is

a

registered trademark

of

the

Canadian Standards Association.

Chapter

1

Model

89033

Safety Considerations

SAFETY

CONSIDERATIONS

GENERAL

This product and related documentation must be re-

viewed for familiarization with safety markings and

instructions before operation.

This product is a Safety Class

I

instrument (provided

with a protective earth terminal).

BEFORE APPLYING POWER

Verify that the product is set to match the available

line voltage and the correct fuse

is

installed.

SAFETY EARTH GROUND

An uninterruptible safety earth ground must be pro-

vided from the main power source to the product input

wiring terminals, power cord,

or

supplied power cord

set.

SAFETY SYMBOLS

Instruction manual symbol: the product will

be marked with this symbol when it

is necessary for the user to refer to the instruction

manual (refer to Table of Contents).

Indicates hazardous voltages.

Indicates earth (ground) terminal.

f

The WARNING sign denotes a

hazard.

It

calls attention to a

procedure, practice, or the like, which,

if

not correctly

performed

or

adhered to, could result in personal in-

jury.

Do

not proceed beyond a WARNING sign until

the indicated conditions are fully understood and met.

The CAUTION sign denotes a haz-

ard.

It

calls attention to an

operating procedure, practice, or the like, which,

if

not

correctly performed

or

adhered to, could result in dam-

age to

or

destruction of part or all

of

the product.

Do

not proceed beyond a CAUTION sign until the indi-

cated conditions are fully understood and met.

Any interruption of the protective (ground-

ing) conductor (inside

or

outside the instru-

ment)

or

disconnecting the protective earth

terminal will cause a potential shock hazard

that could result in personal injury. (Ground-

ing one conductor of a two conductor outlet

is not sufficient protection).

Whenever it is likely that the protection has

been impaired, the instrument must be made

inoperative and be secured against any unin-

tended operation.

If this instrument is to be energized via

an

autotransformer (for voltage reduction) make

sure the common terminal is connected to the

earth terminal of the power source.

Servicing instructions are for use by service-

trained personnel only.

To

avoid dangerous

electric shock, do not perform any servicing

unless qualified to

do

so.

Adjustments described

in

the manual are per-

formed with power supplied to the instrument

while protective covers are removed. Energy

available at many points may,

if

contacted, re-

sult in personal injury.

Capacitors inside the instrument may still be

charged even if the instrument has been dis-

connected from its source of supply.

For

continued protection against fire hazard,

replace the line fuse(s) only with

250V

fuse(s)

of the same current rating and type (for exam-

ple, normal blow, time delay, etc.).

Do

not use

repaired fuses

or

short circuited

fuseholders.

...

111

Safety Considerations Model

89033

ATTENTION

Static Sensitive

Devices

This instrument was constructed

in

an ESD (electro-static dis-

charge) protected environment. This is because most of the semi-

conductor devices used

in

this instrument are susceptible to damage

by static discharge.

Depending on the magnitude of the charge, device substrates can

be punctured

or

destroyed by contact

or

mere proximity of a static

charge. The results can cause degradation of device performance,

early failure,

or

immediate destruction.

These charges are generated

in

numerous ways such

as

simple con-

tact, separation of materials, and normal motions of persons

working with static sensitive devices.

When handling

or

servicing equipment containing static sensitive

devices, adequate precautions must be taken to prevent device dam-

age

or

destruction.

Only those who are thoroughly familiar with industry accepted

techniques for handling static sensitive devices should attempt to

service circuitry with these devices.

In all instances, measures must be taken to prevent static charge

build-up on work surfaces and persons handling the devices.

For further information on ESD precautions, refer to “SPECIAL

HANDLING CONSIDERATIONS FOR STATIC SENSITIVE

DE VICES”

in

Section VIII Service Section.

iv

Model

8903E

Table

of

Contents

CONTENTS

Page

VOLUME

1

.

Section

1

GENERAL INFORMATION

Introduction

.....................

Specifications

............

..........

1-1

Safety Considerations

.....................

1-1

Instruments Covered by Manual

..................

1-1

Serial Numbers

.............................

1-1

Options

..............................

.

1-2

Manual Changes Supplement

......

.........

1-2

.................

1-2

.............................

1-2

Audio Testing

................................

1-2

Transceiver Testing

.................

1-3

Balanced Input

..........................

Systems

......................................

1-3

Options

........................................

1-3

Electrical Options

.............................

1-3

Electrical Option

001

........................

1-3

Internal Plug-in Filter Options

................

1-3

Mechanical Options

...........................

1-4

Front Handle Kit (Option

907)

...............

1-4

Rack Flange Kit (Option

908)

................

1-4

Rack Flange and Front Handle

Combination Kit (Option

909)

..............

1-4

Hewlett-Packard Interface

BUS (HP-IB)

.................................

1-4

Compatibility

............

1-4

Selecting the HP-IB Address

...................

1-4

Accessories Supplied

.............................

1-4

Electrical Equipment Available

...................

1-4

HP-IB Controllers

.............................

1-4

Front-to-Rear-Panel Connectors

Retrofit Kit

................................

1-4

Rear-to-Front-Panel Connectors

Retrofit Kit

...............

1-6

Available

.....................................

1-6

Chassis Slide Mount Kit

.......................

1-6

Chassis Tilt Slide Mount Kit

.

...

1-6

Recommended Test Equipment

...................

1-6

Principles of Operation for

Mechanical Equip

Simplified Block Diagram

.

........

Voltmeter and Notch Filter

.........

Counter

......................................

1-7

Voltage Measurement

........................

1-8

Input Frequency Measurement

................

1-8

Controller

.

Basics of Audio

AC Level

.......................

Frequency

....................................

1-9

DC Level

....................................

1-9

Distortion

..............

SINAD

........

Signal Impurities

..................

1-9

Page

.

Section

2

INSTALLATION

................................

2-1

................................

2.1

Preparation for Use

.............................

2-1

Power Requirements

...........................

2-1

Line Voltage and Fuse Selection

................

2-1

Power Cables

.................................

2-1

HP-IB Address Selection

.......................

2-2

Interconnections

..............................

2-4

Mating Connectors

............................

2-4

Interface Connector

.........................

2-4

Coaxial Connectors

..........................

2-4

Operating Environment

........................

2-4

Bench Operation

..............................

2-5

Rack Mounting

...............................

2-5

Storage and Shipment

...........................

2-5

Environment

.................................

2-5

Packaging

....................................

2-5

Original Packaging

.............

Other Packaging

...............

Section

3

OPERATION

Introduction

.......................

General

......................................

3-1

Turn-On Procedure

............................

3-1A

Local Operation

...............................

3-1

Simplified Operation

.........................

3-2

Panel Features

.......................

Detailed Operating Instructions

........

Supplemental Information

....................

3-2

Operatingg Characteristics

......... .........

3-1

Remote Operation (HP-IB)

.........

Operator’s Checks

.............................

3-2

Basic Functional Checks

.....................

3-2

HP-IB Functional Checks

....................

3-2

Operator’s Maintenance

........................

3-2

Operator’s Checks

...............................

3-8

Basic Functional Checks

........

Preliminary Check

...........

Filter Check

................................

3-9

Distortion

.................................

3-10

SINAD Check

.............................

3-10

DC Level Check

...........................

3-10

HP-IB Functional Checks

.....................

3-11

Remote and Local Messages and the LCL Key

3-12

..................

3-13

.................

3-13

Lockout/Set Local M

...............

3-13

Abort Message

.............................

3-15

Status Byte Message

.......................

3-16

Require Service Message

....................

3-17

Key Triggering

...........................

3-17

Address Recognition

........................

3-11

Sending the Data Message

Receiving the Data Message

Local Lockout and Clear

Clear Message

.......

3-14

Trigger Message and Clear

V

Table

of

Contents

Model

89033

CONTENTS

(cont’d)

Page

Interface Bus

...........................

3-19

HP-IB Compatibility

.

............

3-19

.......................

3-19

....................

3-19

Local Mode

................

........

3-19

Local Capability

......................

3-19

Remote-to-Local Mode Changes

........

3-19

Addressing

.........

...............

3-19

Local Lockout

........................

3-21

Data Messages

......................

Receiving the Data Message

..............

3-21

-

Remote Operation, Hewlett-Packard

Listen Only

..........................

3-21

Data Input Format

....................

3-22

Program Codes

.......................

3-22

Turning Off Functions

............

Programming Numeric Data

...

General Numeric Data Input Format

....

3-23

Triggering Measurements with the

Special Considerations for

Reading Data from the Right

Program Order Considerations

.

Data Message

.......................

3-23

Triggered Operation

..............

or Left Display

.....................

3-24

Talk Only Mode

......................

3-25

Data Output Format

..................

3-25

Data Output Format

..................

3-25

Sending the Data Message

...............

3-24

Talk Status Only Mode

....

Error Output Format

..............

Receiving the Clear Message

.............

3-25

Receiving the Trigger Message

............

3-26

Receiving the Remote Message

...........

3-26

Receiving the Local

Lockout Message

..........

Receiving the Clear Lockout/Set

Receiving the Local Message

.

........

3-26

.....................

3-26

......

3-26

.....

3-26

Receiving the Pass Control Message

Sending the Require Service Message

Selecting the Service Request

Sending the Status Byte Message

Sending the Status Bit

Condition

...................

.......................

Receiving the Abort Message

.............

3-27

HP-IB Syntax and Characteristics

Summary

....

....................

3-29

Page

DETAILED OPERATING INSTRUCTIONS

3-33

..........................

3-33

ion

......................

3-35

Common Mode

.......... .............

3-36

DC Level

...............

.............

3-39

Default Conditions and Power-up

Detector Selection

..............

Display Level in Watts

...............

Distortion

.....

...................

3-43

...................

3-45

Error Disable

......

3-47

Error Message Summary

...................

3-48

Filters

.........................

......

3-51

..........................

3-55

nt

.......................

3-57

HP-IB Address

...........................

3-59

Input Level Range (DC Level)

.............

3-61

.......

3-62

Monitor

.................

...........

3-64

Notch Tune

..............

...........

3-67

Post-Notch Detector Filtering

(Except SINAD)

........................

3-68

Post-Notch Gain

...........

.........

3-69

Rapid Frequency Count

....................

3-70

RATIO and LOG/LIN

....................

3-73

Read Display to HP-IB

..............

3-75

Service Request Condition

.................

3-76

SINAD

..................................

3-78

Special Functions

......

...............

3-80

Time Between Measurements

...............

3-86

Section

4

PERFORMANCE TESTS

-

Sequence

....................

..............

Hold Settings

.............................

3-58

Input Level Range (Except DC Level)

Introduction

....................

Equipment Required

............

Test Record

...............................

4-1

Calibration Cycle

..........................

4-1

Abbreviated Performance Testing

............

4-1

PERFORMANCE

TESTS

..................

4-2

AC Level Accuracy

.........................

4-2

DC Level Accuracy

............

Residual Distortion and Noise

.....

Distortion and SINAD Accuracy

Frequency Accuracy and Sensitivity

.........

4-14

Audio Filters

.............................

4-15

Input Impedance

................

......

4-22

Common-Mode Rejection Ratio

. ......

4-24

Performance Test Record

...... ......

4-26

vi

Model

89033

Table

of

Contents

CONTENTS

(cont’d)

Page

-

Section 5

ADJUSTMENTS

Introduction

.

. .

. . .

.

. . .

. .

.

. .

.

. . . .

5-1

Safety Considerations

. . .

.

. .

.

. .

.

. . .

. .

.

. .

5-1

Equipment Required

. .

.

. .

.

. . .

.

5-1

Factory-Selected Components

.

. . . . . . . . . . .

.

5-1

Post-Repair Tests,

Adjustments, and Checks

.

. . . .

.

. . .

. .

.

. .

5-1

Related Adjustments

. .

. . . . . . .

.

. . .

.

. . . .

5-2

Internal Reference Frequency

. . .

. .

. . .

.

. .

.

. . .

5-3

ADJUSTMENTS

.

. .

.

. .

.

. . . . .

.

. .

.

. .

5-3

Input Flatness

.

. . . . . . . . . .

.

. .

.

. . .

5-4

Common-Mode Rejection

.

. .

.

. .

5-8

Input DC Offset

. .

.

. . . .

.

. .

.

. . .

.

. .

.

5-9

400

Hz High-Pass and Weighting

Bandpass Filters

. . .

.

. . .

.

. .

.

. . .

. .

. . .

.

. .

5-10

Notch Filter Tune and Balance

.

. .

.

. .

.

. . .

5-12

Voltmeter (Using

an

HP-IB

.

. .

.

. . .

.

. . .

.

. .

.

. .

. . .

. .

5-13

Voltmeter (Not Requiring an HP-IB

.

. . . .

.

. .

.

. . .

. .

.

. .

.

. .

.

. . .

5-16

Controller)

vii

Model 89033 General Information

Section

1

GENERAL

INFORMATION

1-1.

INTRODUCTION

This manual contains information required to install,

operate, test, adjust, and service the Hewlett-Packard

Model 89033 Distortion Analyzer. This manual docu-

ments options installed in the Distortion Analyzer

such as rear-panel connections and internal plug-in

filters.

This section of the manual describes the instruments

documented by the manual and covers instrument

description, options, accessories, specifications, and

other basic information. This section also contains

principles of operation on a simplified block diagram

level and basic information on audio measurements.

The other sections contain the following

information:

Section

2,

Installation:

provides information about

initial inspection, preparation for use (including ad-

dress selection for remote operation), and storage and

shipment.

Section

3,

Operation:

provides information about

panel features, and includes operating checks, opera-

ting instructions

for

both local

and

remote operation,

and maintenance information.

Section

4,

Performance Tests:

provides the informa-

tion required to check performance

of

the instrument

against the critical specifications in Table

1

-

1.

Section

5,

Adjustments:

provides the information

required to properly adjust the instrument.

Section

6,

Replaceable Parts:

provides ordering in-

formation for all replaceable parts and assemblies.

Section

7,

Instrument Changes:

provides instrument

modification, recommendations, and procedures.

Section

8,

Service:

provides the information required

to repair the instrument.

Sections

1

through

5

are bound

in

this volume, the

Operation and Calibration Manual.

Sections

6

through

8

are bound in

two

separate volumes, the

Service Man-

ual.

The

Service Manual

is comprised of

an

HP

8903E

Service Supplement,

and

an

HP 8903B Service Manual.

Copies of the

Service Manual

are not supplied with

the instrument unless specifically requested

(as

option

915) at time

of

instrument order. The

Operation and

Calibration Manual

is supplied with the instrument

order. When option

915

is requested, the complete

service manual (the

HP

89033 Service Supplement

and

the

HP8903B Service Manual)

is

supplied with the

instrument order.

Copies of all volumes can be ordered through your

nearest Hewlett-Packard sales office. The part num-

bers are listed on the title page of this manual.

Also listed on the title page

of

this manual, below

the manual part number, is

a

microfiche part number.

This number may be used to order 100

X

150 mm

(4

X

6

inch) microfilm transparencies of this manual.

Each microfiche contains up to

96

photo-duplicates

of the manual’s pages. The microfiche package also

includes the latest

MANUAL

CHANGES

supple-

ments, as well as all pertinent Service Notes.

1-2.

SPECIFICATIONS

Instrument specifications are listed in Table

1-1.

These are the performance

standards,

or

limits against

which the instrument may be tested. Characteristics

listed under Supplemental Information, Table 1-2,

are not warranted specifications but are typical char-

acteristics included as additional information for the

user.

1-3.

SAFETY

CONSIDERATIONS

This product

is

a Safety Class

I

instrument (that is,

provided with a protective earth terminal). The

Distortion Analyzer and all related documentation

must be reviewed for familiarization with safety mark-

ings and instructions before operation. Refer to the

Safety Considerations

page found at the beginning

of this manual for a summary of the safety informa-

tion. Safety information pertinent

to

the task at hand

(installation, performance testing, adjustment,

or

service) is found throughout the manual.

Serial Numbers.

This instrument has

a

two-part ser-

ial number in the form

OOOOAOOOOO

which is stamped

on the serial number plate attached to the rear

of

the instrument. The first four digits and the letter

constitute the serial number prefix, and the last five

digits form the suffix. The prefix

is

the same for all

identical instruments. It changes only when a change

is made to the instrument. The suffix, however, is

assigned sequentially and is different for each instru-

ment. The contents of this manual apply directly to

instruments having the same serial prefix(es) as listed

under SERIAL NUMBERS on the title page.

1-4.

INSTRUMENTS COVERED

BY

MANUAL

1-1

General Information Model 89033

Options.

Electrical Option

001,

internal plug-in filter

options, and various mechanical options are docu-

mented in this manual. The differences are noted

under the appropriate paragraph such as

Options

in

Section

1,

the Replaceable

Parts

List, and the sche-

matic diagrams.

1-5.

MANUAL CHANGES SUPPLEMENT

An instrument manufactured after the printing of

this manual may have a serial prefix that is not listed

on the title page. An unlisted serial prefix indicates

that the instrument differs in some way from those

documented in this manual.

A

“Manual Changes Supplement”

is

shipped with this

manual

to

provide you with the most current change

information available at the time of shipment. In

addition

to

change information the supplement may

contain information for correcting errors in the

manual.

To keep this manual up

to

date and as accurate as

possible, Hewlett-Packard recommends that you peri-

odically request the latest Manual Changes Supple-

ment. The supplement is identified with the print

date and part number that appears on the title page.

Complimentary copies of the supplement are available

from Hewlett-Packard.

1-6.

DESCRIPTION

1-7.

General

The HP Model 89033 Distortion Analyzer

is

an audio

measurement system covering the frequency range

of

20Hz

to

100

kHz. The analyzer can perform

distortion analysis, frequency count, ac level, dc level,

and SINAD measurements. The Distortion Analyzer

reduces the number of instruments required in many

applications involving audio signal characterization.

The Distortion Analyzer is easy to use. All measure-

ments are selected by one

or

two keystrokes. For

distortion measurements, the Distortion Analyzer

automatically ranges to, and tunes to the input signal.

Measurement and output ranges are automatically

selected for optimum resolution and accuracy.

The combined capabilities of the instrument are en-

hanced by microprocessor control, resulting in more

capability than would be available from separate

instruments. For example, using the ratio key allows

you to set a

OdB

or

100%

reference for making

frequency response measurements. Microprocessor

control allows flexible and versatile display formats.

For example, ac level can be displayed in V, mV,

dBm into

600Q2,

watts,

or

as a ratio (in

%

ordB)

referenced to an entered

or

measured value.

Virtually all functions are remotely programmable

through the Hewlett-Packard Interface Bus (HP-IB)‘.

Programming

is

easy and straightforward. All meas-

urements are made through a single input. This elimi-

nates the need

to

switch between multiple inputs

under remote control and reduces software

development time and hardware costs. The Distortion

Analyzer measures the true rms level on all ac meas-

urements. True rms measurements assure greater

accuracy when measuring complex waveforms and

noise. For those applications where average detection

is required, the analyzer can be switched to average

responding (rms calibrated) detection via a front-

panel key. Accurate distortion measurements typically

can be made

to

less than 0.003% (-9OdB) between

20

Hz

and

20

kHz.

1-8.

Audio Testing

The Distortion Analyzer has numerous features which

make audio testing simple and convenient. For

example, distortion results can be displayed in

%

ora.

AC level measurements can be displayed in

volts, dBm into

600Q,

or

watts. Measurement results

can be displayed in

%

or

dB

relative to a measured

or

entered value. Finding the 3dB points of filters

and amplifiers is simplified by using the relative

display feature. The Distortion Analyzer also features

high accuracy. The internal Voltmeter flatness

is

bet-

ter than

0.5%

(0.05

dB)

over the range of

20

Hz to

20

kHz. Residual Distortion is typically 0.003% (-90

dB)

over the same range. See Figure

1-1.

Balanced Input.

The Distortion Analyzer has a selec-

table balanced input configuration for testing bal-

anced devices. For example, in the quest for higher

output power, many audio amplifiers use bridged out-

put stages. Such amplifiers can be difficult

to

charac-

terize because their outputs cannot be grounded. To

test these devices, the usual approach has been to

use a balanced, calibrated isolation transformer con-

nected to

an

analyzer with an unbalanced input. The

balanced input on the Distortion Analyzer make

transformers unnecessary. With the analyzer input

in the float position, connect the bridged device di-

rectly to the Distortion Analyzer

to

make

measurements.

I

HP-IB:

Not just

IEEE-488.

but the hardware, documentation

and support that delivers the shortest path to a measurement

system.

1-2

Model 89033 General Information

-70

E

w

-75

??

g

-80

6

-80

5

-a5

U

-

I-

a:

-90

--

..

.

FREQUENCY

Figure

1-1.

Typical Analyzer Residual

Distortion

1-9.

Transceiver Testing

The Distortion Analyzer has several measurements

and features specifically designed for transceiver test-

ing.

It

has SINAD measurements for receiver testing,

optional internal plug-in weighting filters for testing

to international standards, a reciprocal counter for

measuring squelch tones, and an optional internal

plug-in

400

Hz

high-pass filter for eliminating squelch

tones when measuring transmitter audio distortion.

SINAD is one of the most basic receiver measure-

ments.

It

must be made repeatedly when performing

sensitivity

or

adjacent-channel sensitivity tests. In

the Distortion Analyzer, the SINAD measurement

is

more heavily filtered than the distortion measurement

in order

to

smooth the noisy signals encountered in

receiver testing. The filtering

is

optimized for excel-

lent repeatability and speed

(2

readingslsecond

typ-

ical). Some automatic distortion analyzers have a

tendency to become untuned when measuring SINAD

on noisy signals. The Distortion Analyzer overcomes

this problem by providing a front panel key which

locks the notch filter at the input frequency.

For

SINAD ratios less than 25

cU3,

a Special Function

can be used to round the digital display

to

the nearest

0.5dl3 to reduce digit flicker.

For

accurate noise ratio measurements, the Distortion

Analyzer uses true

rms

detection for SINAD. Most

older instruments employ average detection which

reads low for noise. The discrepancy can be 1.5dT3

or greater and varies with the ratio being measured.

For

correlating results with past test data, the

Distortion Analyzer’s detector can be switched via a

front-panel key to an average responding

configuration.

tones up to

250

Hz

is

greater than

40

dl3.

Therefore,

audio distortion measurements to

1

%

residual

distortion can be made without disabling the trans-

mitter squelch tones.

Under remote control, the Distortion Analyzer can

count burst tone sequences. Typically the maximum

count rate is

8

ms/reading.

1-10.

Systems

The Distortion Analyzer features capabilities for gen-

eral systems applications. The distortion measure-

ments are fully automatic, programmable, and fast.

The typical time to tune and return the first distortion

measurement is

1.5

seconds with a measurement rate

of

2

readingslsecond thereafter. The residual

distortion of the analyzer is typically

0.003%

(-90

dB)

between 20Hz and 20kHz.

Often, systems applications involve measuring low

level ac signals. The Distortion Analyzer features a

full range ac level display of 0.3000mV with an

accuracy of

4%

of reading

(2%

of reading for levels

>50 mV and from

20

Hz to 20

kHz).

The ac detector

is switchable between true rms and average respond-

ing detection. The

3

dl3

measurement bandwidth for

both detectors is greater than

500

kHz.

Since many systems have noise problems, the

Distortion Analyzer has both 30 and

80

kHz low-pass

filters

to

reject high frequency noise. In addition, the

optional internal plug-in

400

Hz

high-pass filter atten-

uates line-related hum and noise by more than 68

dB.

A

special binary programming mode is available in

remote operation. The rapid frequency count mode

provides a packed, four-byte output for fast counting

over HP-IB.

1-1 1.

OPTIONS

1-1

2.

Electrical Options

Electrical Option

001.

This option provides a rear-

panel (instead of front-panel) connection for the

INPUT and MONITOR connectors.

Internal Plug-in Filter Options.

The Distortion

Analyzer has two internal plug-in filter positions;

each position can be loaded with any one of six

optional filters. Each filter is referenced to

its

corre-

sponding filter position by one of two option numbers.

For

example, the

400

Hz High-Pass Filter Option can

be ordered as Option

010

which corresponds to the

left-most filter position,

or

as Option

050

which corre-

sponds to the right-most filter position. These op-

For

transceivers, the Distortion Analyzer has an op-

tional, internal plug-in seven-pole

400

Hz

high-pass

filter for rejecting squelch tones. Rejection of squelch

tional plug-in filters can be configured in any

combination desired.

If

there

is

no filter ordered

for

a position, a jumper wire is loaded and a label marked

1-3

General Information Model 89033

“No Filter” is placed above the filter key on the front

panel. The following list includes the name and option

numbers for each available filter.

the Distortion Analyzer, refer to Remote Operation,

Hewlett-Packard Interface Bus in Section 3 of this

manual.

400 Hz High-Pass Filter (Option 010, 050).

CCITT Weighting Filter (Option 011, 051).

CCIR Weighting Filter (Option

012,

052).

C-MESSAGE Weighting Filter (Option 013, 053).

CCIR/ARM Weighting Filter (Option 014, 054).

“A”

Weighting Filter (Option 015, 055).

Specific information on each plug-in filter option can

be found in the Detailed Operating Instructions in

Section

3

under “Filters”.

1-16.

Selecting the HP-IB Address

The

HP-IB

address switches are located within the

Distortion Analyzer. The switches represent a five-bit

binary number. This number represents the talk and

listen address characters which an HP-IB controller

is capable of generating. In addition, two more

switches allow the Distortion Analyzer to be set to

talk only

or

listen only.

A

table in Section

2

shows

all HP-IB talk and listen addresses. Refer

to

HP-IB

Address

Selection in Section

2

of this manual.

1-13.

Mechanical Options

1-1

7.

ACCESSORIES SUPPLIED

The following options may have been ordered and

received with the Distortion Analyzer.

If

they were

not ordered with the original shipment and are now

desired, they can be ordered from the nearest Hewlett-

Packard office using the part number included in

each

of

the following paragraphs. The mechanical

options are shown in Figure 1-2.

Front Handle Kit (Option

907).

Ease of handling

is

increased with the front-panel handles. Order HP

part number 5061-9689.

Rack Flange Kit (Option

908).

The Distortion

Analyzer can be solidly mounted to the instrument

rack using the flange kit. Order HP part number

506 1-9677.

Rack Flange and Front Handle Combination Kit

(Option

909).

This

is

not a front handle kit and a

rack flange kit packaged together; it

is

composed of

a unique part which combines both functions. Order

HP part number 5061-9683.

1-14.

HEWLETT-PACKARD INTERFACE BUS

(HP-16)

1-15.

Compatibility

The Distortion Analyzer is compatible with HP-IB

to the extent indicated by the following code: SH1,

AH1, T5,

TEO,

L3, LEO, SR1, RL1,

PPO,

DC1,

DT1, CO, El. The Distortion Analyzer interfaces

with the bus via open collector TTL circuitry. An

explanation of the compatibility code can be found

in IEEE Standard 488, “IEEE Standard Digital

Interface for Programmable Instrumentation”

or

the

identical ANSI Standard MC1.l. For more detailed

information relating to programmable control of

The accessories supplied with the Distortion Analyzer

are shown in Figure

1-2.

Time delay fuses with a 1.5A rating for 100/120 Vac

operation

(HP

2110-0059) and

a

0.75A rating for

220/240 Vac operation

(HP

2110-0018) are supplied.

One fuse is installed in the instrument at the time

of shipment. The rating of the installed fuse is selected

according to the line voltage specified by the customer.

If

the voltage

is

not specified, the rating of the in-

stalled fuse will be selected according to the country

of destination.

For Option

001

only,

two

type BNC-to-banana-plug

adapters (HP 5021-0844) are also supplied for use

when double-ended inputs

or

outputs are desired. The

conductor of the banana jack is connected to the

center conductor

of

the BNC adapter connector.

These adapters are used when the front-panel INPUT

or

OUTPUT FLOAT switches are set to FLOAT.

1-18.

ELECTRICAL EQUIPMENT AVAILABLE

(Also refer to Service Accessories, Table 1-4.)

1-1

9.

HP-I6 Controllers

The Distortion Analyzer has an HP-IB interface and

can be used with any HP-IB compatible computing

controller

or

computer for automatic systems

applications.

1-20.

Front-to-Rear-Panel Connectors

This kit contains all the necessary components and

full instructions for converting instruments with

front-panel connections for INPUT and MONITOR

to

rear-panel connections. Order

HP

part number

08903-60177. After installation and calibration, per-

formance will be identical

to

the HP 89033 Option 001.

Retrofit Kit

1-4

Model

89033

General

Information

SPARE INTERNAL FUSES BNC TO BANANA PLUG ADAPTER

OPTION

909

RACK FLANGE AND FRONT

HANDLE COMBINATION KIT

OPTION

907

FRONT HANDLE KIT

OPTION

908

RACK

FLANGE KIT

NOTE:

Refer

to

ACCESSORIES

SUPPLIED,

for

more

details.

Figure

1-2.

HP

Model

8903E

Accessories Supplied, and Options

907, 908,

and

909

1-5

General Information

-

1-21. Rear-to-Front-Panel Connectors

Retrofit Kit

If

41

This kit contains all the necessary components and

full instructions for converting instruments with rear-

panel connections for INPUT and MONITOR to

front-panel connections. Order HP part number 08903-

60178. After installation and calibration, performance

will be identical to the standard HP89033.

1-22. MECHANICAL EQUIPMENT

AVAILABLE

1-23. Chassis Slide Mount Kit

This kit is extremely useful when the Distortion

Analyzer is rack mounted. Access

to

internal circuits

and components

or

the rear-panel

is

possible without

removing the instrument from the rack. Order HP

part number 1494-0060 for 431.8mm (17in.) fixed

slides, and part number 1494-0061 for the correct

adapters for non-HP rack enclosures.

1-24. Chassis Tilt Slide Mount Kit

This kit is the same as the Chassis Slide Mount Kit

above except it also allows the tilting of the instru-

ment up

or

down 90". Order HP part number 1494-

0062 for 431.8mm

(17

in.) tilting slides, and part

number 1494-0061 for the correct adapters for non-

HP rack enclosures.

Model 89033

1-25. RECOMMENDED TEST EQUIPMENT

Table 1-3 lists the test equipment recommended for

use in testing, adjusting, and servicing the Distortion

Analyzer. If any of the recommended equipment is

unavailable, instruments with equivalent minimum

specifications may be substituted. Table 1-3 also in-

cludes some alternate equipment listings.

1-26. PRINCIPLES OF OPERATION

FOR

SIMPLIFIED BLOCK DIAGRAM

The HP Model 89033 Distortion Analyzer combines

two instruments into one: a general purpose voltmeter

with a tunable notch filter at the input, and a

frequency counter. Measurements are managed by a

microprocessor-based Controller. This combination

forms an instrument that can make most common

measurements on audio circuits automatically.

To

add to its versatility, the Distortion Analyzer also

has selectable input filters, and HP-IB

programmability.

The operation of the instrument is described in the

following order: Voltmeter and Notch Filter, Counter,

and Controller. Refer

to

Figure 1-3.

1-27.

Voltmeter and Notch Filter

The amplitude measurement path flows from the

INPUT connector to the MONITOR output (on the

front panel) and includes the Input and Output RMS/

Average Detectors, dc voltmeter (the Voltage-to-Time

Converter and Counter). Measurements are made on

-1

0

oonm

D.

KEYBOARD AND DISPLAY

Figure

1-3.

Simplified

HP

8903E

Distortion Analyzer

Block

Diagram

1-6

Model 89033 General Information

the difference between the signals on the inner

conductor and shield of the INPUT connector

or,

for option

001,

the HIGH and LOW connectors. Com-

bined differential and common-mode levels can be as

high as 300V. However, for safety purposes only 42V

maximum is allowed on the outer conductor of the

single BNC input connector when in the FLOAT

position.

The input signal is ac coupled for all measurement

modes except dc level. The signal

is

scaled by the

Input Attenuator to a level of 3V

or

less. To protect

the active circuits that follow, the Over-Voltage Pro-

tection circuit opens whenever its input exceeds 15V.

The differential signal

is

converted to a single-ended

signal (that is, a signal referenced to ground) and

amplified. In the dc level mode, the dc voltage

is

measured at this point by the dc voltmeter. The

signal is further amplified by a Programmable Gain

Amplifier which

is

ac coupled. The gain of this ampli-

fier and the Differential-to-Single-Ended Amplifier

are programmed to keep the signal level going into

the Input Detector and Notch Filter between 1.7 and

3 Vrms. This optimizes the effectiveness and accuracy

of the amplifiers, particularly in the distortion and

SINAD modes.

The output from the first Programmable Gain Ampli-

fier is converted to dc by the Ranging RMS Detector,

and measured by the dc voltmeter. The output of

this detector

is

used

to

set the gain of the input

circuits. The signal then passes through the internal

plug-in HP/BP filters to the input RMS/Average

detector and becomes the numerator of the SINAD

measurement, and the denominator of the distortion

measurement (refer

to

Basics of Audio Measurements).

The Input RMS/Average Detector

is

not used to

make the ac level measurement; the Output RMS/

Average Detector

is

used for this measurement. For

dc level measurements, the Ranging RMS Detector

also monitors the ac component

(if

there

is

one) and

lowers the gain of the input path

if

the signal will

overload the input amplifiers; otherwise, the gain of

the input path is determined by measuring the dc

level.

At

this point, one of the two internal plug-in

filters can be inserted into the signal path. The 400

Hz

High-Pass Filter is usually used to suppress line hum,

or

the low frequency squelch tone used on some mobile

transceivers. The Weighting Filters have bandpass

frequency responses that simulate the “average” re-

sponse of human hearing. In the SINAD, distortion,

and distortion level modes, the frequency of the input

signal is counted at the output of the internal plug-in

HP/BP Filters.

When measuring SINAD, distortion,

or

distortion

level, the fundamental of the signal is removed by

the Notch Filter. The output from the filter is the

distortion and noise of the signal. In the ac level

mode, the Notch Filter

is

bypassed. After amplifying

and low-pass filtering, the output from the Notch

Filter is converted to dc by the Output RMS/Average

Detector, and measured by the dc voltmeter.

When measuring distortion, distortion level,

or

SINAD, the Notch Filter

is

automatically tuned to

the frequency counted at the input to the filter. Coarse

tuning is via the Controller. Fine tuning and balance

are via circuitry internal to the Notch Filter. In

SINAD mode, a front-panel key allows you to lock

the notch at a given input frequency,

so

that the

notch will not become untuned in the presence

of

noise. The two Programmable Gain Amplifiers,

following the Notch Filter, amplify the low-level noise

and distortion signals from the Notch Filter. The

overall gain of the two amplifiers is normally set to

maintain a signal level of 0.3 to 3V

at

the MONTIOR

output.

The 30 kHz and

80

kHz LP Filters are selected from

the Keyboard. With no low-pass filtering, the 3dB

bandwidth of the measurement system is approxi-

mately 750

kHz.

The filters are most often used to

remove the high-frequency noise components in low-

frequency SINAD and distortion measurements. The

output from the second Programmable Gain Amplifier

drives the front-panel MONITOR output connector.

The frequency of this signal

is

also measured by the

Counter in the ac level mode because of the increased

sensitivity at this point.

The Output Detector

is

read by the dc voltmeter in

the ac level, SINAD (the denominator), distortion

(the numerator), and distortion level modes.

It

is also

used to set the gain of the two Programmable Gain

Amplifiers. Both the input and output detectors can

be configured via front-panel keys to respond to the

absolute average of the signal instead of the true rms

value. The Voltage-to-Time Converter converts the

dc inputs into a time interval which is measured by

the Counter.

1-28.

Counter

The Counter

is

a reciprocal counter. To measure

frequency,

it

counts the period

of

one

or

more cycles

of the signal at its input, then the Controller divides

the number of periods by the accumulated count.

The reference for the Counter

is

the 2MHz Time

Base which also

is

the clock for the Controller. The

Counter has three inputs and two modes of operation:

1-7

General Information Model 89033

Voltage Measurement.

The time interval from the

Voltage-to-Time Converter is counted. The accumu-

lated count is proportional to the dc voltage. For

direct measurements (ac level, dc level, and distortion

level), the count is processed directly by the Controller

and displayed on the right display.

For

ratio measure-

ments (SINAD and distortion), the counts of two

successive measurements are processed and displayed.

For

SINAD and distortion, the ratio of the outputs

of the Input and Output RMS/Average Detectors is

computed.

Input Frequency Measurement.

The signal from the

last Programmable Gain Amplifier

or

the internal

plug-in HP/BP Filters

is

conditioned by the Counter

Input Schmitt Trigger

to

make it compatible with

the Counter’s input. The period of the signal is then

counted, the count

is

processed by the Controller,

and the frequency

is

displayed on the left display.

1-29. Controller

The entire operation of the instrument is under con-

trol of a microprocessor-based Controller. The Con-

troller sets up the instrument at turn-on, interprets

Keyboard entries, executes changes in mode of opera-

tion, continually monitors instrument operation,

sends measurement results and error messages to the

front-panel displays, and interfaces with HP-IB. In

addition,

its

computing capability is used to simplify

circuit operation. For example,

it

forms the last stage

of the Counter, converts measurement results into

ratios (in

%

ora),

etc.

It

also contains routines

useful for servicing the instrument.

1-30. BASICS

OF

AUDIO MEASUREMENTS

The “audio” frequency range is usually taken to be

from

20

Hz to

20

kHz. Few people have hearing that

good, but the term is a convenient one to describe

sub-RF frequencies encountered in electronics. The

frequency range of the Distortion Analyzer extends

beyond the audio range

to

include fundamentals up

to 100 kHz.

Electronic instrumentation provides most of the tools

for quantitative analysis of audio signals. Thus, if

the signal

is

non-electrical (for example, mechanical

or

acoustic),

it

must be converted to

an

electrical

signal by a transducer of some kind (for example,

strain gauge

or

microphone) before it can be analyzed.

Apart from attentive listening to a hi-fi system, the

most intuitive way of analyzing an electrical signal

in the audio range is visually with an oscilloscope.

Here you get a feeling for the signal’s size (loudness),

frequency (pitch), and shape (timbre). You can also

determine

if

these parameters change with time

or

are stable, and you can even make some quantitative

measurements on it (for example, peak level, dc offset,

period, risetime, etc.) Many times, however, the pa-

rameter sought does not lend itself to easy visual

analysis. Thus, the Distortion Analyzer was designed.

It

combines into one instrument

a

series of general

and specialized instruments, under microprocessor

control, that make

it

easy for you to obtain accurate,

quantitative measurements on audio signals of any

general waveshape.

1-31. AC Level

Consider the very common measurement of a signal’s

ac rms level. To make this measurement with an

oscilloscope, you must first decide the nature of the

signal, because from it, the relationship of the peak

level to the rms level can be mathematically

determined. If the signal is sinusoidal, for example,

the rms value is the peak amplitude divided by

5.

This measurement

is

greatly simplified with

an

rms

voltmeter which electronically measures the rms level

and displays the result. However, no other informa-

tion about the signal is provided. The Distortion

Analyzer contains both an rms and an average re-

sponding voltmeter. The rms level of the signal is

displayed whenever the AC Level mode is selected.

The average level can be displayed by pressing the

AVG/RMS key. (When the LED is lit, the analyzer

is

in Average mode.)

A

special function is also pro-

vided which converts the measurement result into

watts

for

a

specified (external) load resistance (access-

able only through HP-IB).

Another important ac signal characteristic is the vari-

ation in level vs. frequency (flatness).

Of

course you

can easily set a reference level (such as

1V)

at a

particular frequency (such as

1

kHz) and monitor the

change in level as the input frequency is changed.

(The external source’s level

is

assumed to be flat;

otherwise,

it

too must be checked.) The Distortion

Analyzer makes this measurement easier in two ways.

First, the reference can be set to

100%

or

OdB

by

the press of a button (the RATIO key). Second, the

results can be logged into a controller over HP-IB

to be plotted on a printer

or

plotter.

An additional parameter related to ac level is gain,

and more often, gain vs. frequency. To make a gain

measurement, measure the input to the device, then

the output, and take the ratio. You first

set

an

external

source as desired, then either measure

it

or

set it

as

a reference (press RATIO). Then measure the output.

The result can be expressed in either

%

or&.

If

desired, an external source can be swept and the gain

plotted as a function of frequency.

1-8

Model

89033

General Information

1-32. Frequency

Another common and basic measurement is

frequency. With an oscilloscope, you simply determine

the time interval between like points on the repetitive

waveform and take the reciprocal. With a frequency

counter, frequency

is

measured electronically and

displayed. The measurement is easier and usually

much more accurate than could be made visually with

an

oscilloscope.

The Distortion Analyzer contains a counter which

displays the frequency of the input signal for all ac

measurements.

It

should be noted that the counter

is a reciprocal type;

it

measures the period of the

signal (as you do with an oscilloscope) and computes

the reciprocal

to

obtain the frequency. The advantage

of this technique

is

that for low (audio) frequencies,

higher resolution is obtained in a shorter

measurement time.

1-33.

DC

Level

Although not part of an audio signal, dc level

is

a

quantity often encountered in audio equipment (for

example, bias voltages and outputs from ac-to-dc con-

verters). Sometimes plots of dc level

vs.

frequency

are desired (as in the case of an ac-to-dc converter).

The Distortion Analyzer has dc level as one of its

measurement modes.

1-34. Signal Impurities

Distortion and SINAD are used to describe the impur-

ity content of a signal. These terms are somewhat

related and can often be confused.

A

pure signal

is

defined as a perfect sinusoid, that is, one whose

frequency spectrum contains only a single spectral

component. Impurities are not always undesirable.

Impurities, for example, are what add character to

the sound of musical instruments. Pure signals in

music sound monotonous.

However, when testing a linear audio system,

if

a

pure signal is applied to the input, anything but a

pure signal at the output indicates that the system

is

degrading the signal. There are several common

classifications

of

impurities: harmonic distortion (har-

monics of the fundamental), intermodulation

distortion (beat signals

of

two

or

more non-related

signals), noise (random signals), and spurious signals

(for example, line hum and interference). All but

intermodulation distortion are easily measured by the

Distortion Analyzer.

1-35. Distortion

Harmonic distortion on a spectrally pure signal is

created by non-linearities in the circuit through which

it

passes. The non-linearities can arise in the transfer

characteristics of the active devices

or

by running

the active device into saturation

or

cutoff. Often,

distortion can be reduced by reducing the signal level,

filtering,

or

adding negative feedback.

According to Fourier mathematics, the non-linear

terms in the circuit’s transfer function give rise to

harmonics of the signal. Total harmonic distortion

(THD) is usually defined as the ratio of the rms sum

of the harmonics to the rms level of the fundamental.

The ratio is usually converted to

%

ora.

An oscilloscope gives only a rough indication of the

amount of distortion present on a signal.

A

general

rule of thumb

is

that

if

the non-linearity causing the

distortion is “gentle” (for example, not clipped), a

trained eye can discern distortion as low a

5%

on

an oscilloscope display. Figure

1-4

shows several ex-

amples of waveforms with

5%

THD and the compo-

nents that combined to produce them

(5%

distortion

would be considered quite high in a quality hi-fi

amplifier).

An audio spectrum analyzer, which allows the user

to see the magnitude of all harmonics, is perhaps

the best instrument to measure harmonic

distortion. The audio spectrum analyzer method,

however, requires a fairly expensive instrument

and some mathematical manipulation.

The traditional method of measuring distortion (ac-

cepted by the Institute of High Fidelity2 and others)

is with a distortion analyzer. The method

is

simple

and adequate for most situations. With a distortion

analyzer, you simply measure the signal level and set

it

up as a reference, then you insert a notch filter,

tuned to the frequency of the fundamental, and

measure the output of the filter relative to the input.

This is the method used by the Distortion Analyzer

in the DISTN mode where the tuning and measuring

are done automatically. When using the distortion

analyzer method,

it

is

important to understand that

the measurement result

is

not “total harmonic

distortion”

as

defined above except under the condi-

tion that the distortion is not too excessive but that

it

does predominate over any other signal impurities.

Some examples will illustrate these restrictions.

Consider the case of excessive harmonic distortion.

Let us use the example of a signal with

10%

actual

total harmonic distortion in which all the distortion

comes from the second harmonic. The second har-

monic is then

20

m

below the fundamental as viewed

*The Institute

of

High Fidelity, Inc., Standard Methods

Of

Measurement

For

Audio

Amplifiers,

The Institute

of

High Fidel-

ity, Inc.,

New

York

(1978),

p.

9.

1-9

General Information Model

89033

on a spectrum analyzer. When this signal is measured

by a distortion analyzer, an error results from the

first

part of the measurement (measuring the input

level) because the input level is not quite the same

as the level of the fundamental. If the fundamental

level were

1

Vrms, the second harmonic level would

be

0.1

Vrms (one-tenth

of

the fundamental). The

total input level (measured with a true rms voltmeter)

is the rms sum of the two components, namely,

Input

=

v/(1)2

+

(0.1)2

=

1.005V

or

0.5%

high. Thus, the measurement result would

be

9.95%

distortion instead of the true

10%.

Actually,

you can see

that

the distortion must really be excessive

to affect the measurement significantly.

Now consider the case where other types of impurities

are significant. Suppose the actual total harmonic

distortion is

1%

but that there is an additional hum

component that has a level that is

1%

of the funda-

mental level. The distortion measured by a distortion

analyzer will be

1.4%

(that is,

40%

or

3

dB

high).

How, then, can you be sure that the result is a valid

measurement of distortion? One way

is

to observe

the MONITOR output with an oscilloscope.

If

the

waveform is clean and harmonically related to the

fundamental, the measurement

is

actual total har-

monic distortion. If

it

is not, selectable filters are

provided to remove unwanted signals. Use the op-

tional

400

Hz

High-Pass Filter to remove line hum.

Use the

30

kHz

or

80

kHz Low Pass Filter to remove

out-of-band noise. However, select only filters that

do not affect the fundamental and the harmonics

of

interest. Sometimes it is desired

to

include hum and

noise as part of the “distortion” measurement. For

this reason, the measurement is often referred to

as

a THD+N (total harmonic distortion plus noise)

measurement

.

1-36.

SINAD

For most practical purposes the SINAD measurement,

as made by the Distortion Analyzer, is equal to the

reciprocal

of

the distortion measurement.

It

is

usually

expressed indB. The notch filter is coarsely pro-

grammed to the input frequency by the microproces-

sor

(but fine tuned to the signal at

its

input). When

measuring SINAD in the presence of large amounts

of impurities, a front-panel key locks the coarse tuning

of the notch filter at the correct input frequency.

SINAD

is

an acronym for SIgnal, Noise, And

Distortion. The ratio (normally expressed in

dF3)

com-

puted in the SINAD measurement is

rms

value

of

signal,

noise and distortion

rms

value

of

noise and distortion

SINAD

=

20

log

The equation eliminates the two restrictions discussed

in connection with the distortion measurement.

SINAD

is

used most often in determining the sensitiv-

ity of

a

receiver. Receiver sensitivity

is

defined

as

the RF level that, when modulated in a specified

manner with a pure audio tone, creates a certain

SINAD (usually

10

or

12dB)

at the receiver’s audio

output. (The tone can just be discerned in the noise.)

Sometimes a noise weighting filter is required in the

receiver sensitivity measurement. Optional plug-in

Weighting Filters modify the frequency response of

the Distortion Analyzer with a bandpass characteris-

tic

that

approximates the response of human hearing.

Weighting Filters which meet most international

standards are available.

1-10

Model

89033

General Information

I

SIN X AND

0.05

COS

2X

SIN X AND

0.05

SIN 2X

SIN X

+

0.05

SIN 2X SIN X

+

0.05

COS

2X

SIN X AND

0.05

SIN 3X SIN X AND

0.05

COS

3X

SIN X

+

0.05

SIN 3X SIN

X

+

0.05

COS

3X

Figure

1-4.

Several Waveforms Each

With

5%

THD

and the Signal Components Which Produced Them

1-11

General Information Model

89033

Table

1-1.

Specifications

(1

of

4)

All parameters describe performance in automatic operation or with properly set manual controls with a 1/2-hour

warrnup period.

MEASUREMENT

Characteristic

SINAD

Fundamental

Display Range

Accuracy

Frequency Range

Input Voltage Range

Residual Noise and

Distortion (the

higher

of)

DISTORTION

Fundamental

Display Range

Frequency Range

Accuracy

Input Voltage Range

Residual Noise and

Distortion (the

higher of)

AC

LEVEL

Full Range Display

Overrange

Accuracy

DC

LEVEL

Full Range Display

Overrange

Accuracy

Performance Limits

20

Hz

to

100 kHz

0

to

99.99

dB

21 dB

e2

dB

50 rnV to 300V

-80 dB or 15 pV

-70 dB or 45 pV

-65 dB or 45

pV

20 Hz to 100 kHz

0.001% to 100%

21 dB

e2

dB

50

rnV

to 300V

(-99.99

to

0

dB)

-80

dB or 15 pV

-70 dB or 45

pV

-65 dB or 45

UV

300.0V, 30.00V,

3.000V, .3000V,

30.00 rnV,

3.000 rnV,

.3000 mV

33%

2

2%

2

4%

e

4%

300.0V, 48.00V,

16.00V,

4.00V

33%

e 1

.O%

of reading

e6 rnV

Conditions

20 Hz to

20

kHz (unfiltered or with low-pass filters)

20 kHz to 100 kHz

20 Hz to

20

kHz; 80 kHz BW

20

Hz to 50 kHz;

500

kHz BW

50 kHz to 100 kHz;

500

kHz BW

20 Hz to

20

kHz (unfiltered or with low-pass filters)

20 kHz to 100 kHz

20

Hz to

20

kHz; 80 kHz BW

20

kHz to 50 kHz;

500

kHz BW

50 kHz to 100 kHz; 500 kHz BW

Except on the 300.0V range

50 rnV to 300V;

20

Hz to 20 kHz

50 rnV to 300V;

20

kHz to 100 kHz

0.3

rnV

to 50rnV;

20

Hz

to 100 kHz

Except on the 300.0V range

600 mV

to

300V

Vin <600 rnV

1-12

Model

89033

General

Information

Table

1-1.

Specifications

(2

of

4)

MEASUREMENT

(Cont'd)

Characteristic

FREQUENCY

Measurement Range

Resolution

Accuracy

Sensitivity

STANDARD AUDIO

FILTERS

30 kHz Low-pass Filter

3 dB Cutoff

Frequency

Rolloff

80 kHz Low-pass Filter

3 dB Cutoff

Frequency

Rolloff

PLUG-IN AUDIO FILTERS

400 Hz Highpass Filter

3 dB Cutoff Frequency

Rolloff

CCllT Weighting Filter

Deviation from Ideal

Response:

CClR Weighting Filter

Deviation from Ideal

Response:

Performance Limits

20 Hz to

150

kHz

20 Hz to 100

kHz

5

digits

0.01

Hz

~(0.004%

+1

digit)

50

mV

5.0

mV

30

t2

kHz

3rd order response,

18 dB/octave or

60 dB/decade

80 24 kHz

3rd order response,

18 dB/octave or

60 dB/decade

400 240 Hz

7th order response:

42 dB/octave

or

140 dB/decade

20.2 dB

21

dB

+2 dB

23

dB

+0.1 dB

+0.2 dB

20.4 dB

20.5 dB

~1.0

dB

22.0

dB

Conditions

In ac level mode

In

distortion and SINAD modes

Frequencies

>lo0

Hz

Frequencies 400 Hz

Distortion and SINAD modes only

In ac level mode only

CCllT Recommendation P53

20

to 55"C, 80% relative humidity

At 800 Hz

300 Hz to 3 kHz

50

Hz to 3.5 kHz

3.5

kHz to

5

kHz

CCIR Recommendation 468-2, DIN 45405

20

to 55OC, 80% relative humidity

At 6.3 kHz

6.3 kHz to

7.1

kHz

7.1

kHz to

10

kHz

200 Hz to 6.3 kHz

31.5

Hz to 200 Hz,

10

kHz to

20

kHz

20

kHz to

31.5

kHz

1-13

General Information

Model

89033

Table

1-1.

Specifications

(3

of

4)

I

MEASUREMENT

(Cont'd)

I

Characteristic

~~

PLUG-IN AUDIO

FILTERS

(Cont'd)

C-MESSAGE Weighting

Filter

Deviation from

Ideal Response:

CCIR/ARM Weighting

Filter

Deviation from

Ideal Response:

"A"-Weight Filter

Deviation from

Ideal Response:

TEMPERATURE

Operating

Storage

INPUT TYPE

MAXIMUM INPUT

INPUT IMPEDANCE

Resistance

Shunt Capacitance

COMMON MODE

REJECTION RATIO

REMOTE OPERATION

Performance

Limits

20.1

dB

21.0

dB

20.1

dB

20.2

dB

20.4

dB

20.5

dB

21.0

dB

22.0

dB

20.1

dB

20.5 dB

21.0

dB

0"

to

55OC

-550

to

75OC

Balanced

42V

Peak

42V

Peak

100

kSZ

21%

101

kSZ

21%

<300

pF

>60

dB

>45

dB

>30

dB

HP-IB STD

488-1978

Compatibility Code:

SH1,

AH1,

T5, TEO,

L3,

LEO

SRI,

RL1,

PPO,

DC1,

DT1

,

CO,

El

Conditions

'er BSTM

41004

!O

to

55"C,

80%

relative humidity

At

1

kHz

60

Hz to

5

kHz

XIR Recommendation

486-2,

averaging responding meter,

3olby Labs bulletin No.

19/4.

20

to

55OC,

80%

relative humidity

At

6.3

kHz

6.3

kHz to

7.1

kHz

7.1

kHz to

10

kHz

200

Ht

to

6.3

kHz

31.5

Hz to

200

Hz, 10 kHz to

20

kHz

20

kHz to

31.5

kHz

IEC Recomendation

179

and ANSI

3.4,

type

1

sound level

meter

20

to 55OC,

80%

relative humidity

At

1

kHz

20

Hz to

10

kHz

10

kHz to

20

kHz

Full differential

Differentially applied, or between high input and ground.

Between low input and ground.

Except in dc level mode

In dc level mode only

Each terminal to ground

20

Hz to

1

kHz,

VIN

<

2V

20

Hz to

1

kHz

20 Hz to

20

kHz

The Hewlett-Packard Interface Bus (HP-IB) is Hewlett-

Packard Company's implementation of

IEEE

Std.

488-1 978,

"Digital Interface for Programmable Instrumentation". All func-

tions except the line switch and

the

low

terminal float/

ground switch are remotely controllable.

1-14

Model

89033

General

Information

Table

1-1.

Specifications

(4

of

4)

GENERAL

I

Characteristic

~ ~~

POWER

REQUIREMENTS

Line Voltage

100, 120, 220,

240 Vac

100, 120 Vac

I

POWER DISSIPATION

CONDUCTED AND

RADIATED

INTERFERENCE (EMI)

CONDUCTED AND

RADIATED

SUSCEPTIBILITY

I

NET

DIMENSIONS

(Full

Envelope)

Height

Width

Depth

Performance Limits

+5%,

-10%

+5%,

-10%

100

V.A maximum

MIL STD 461B

MIL STD 461B-1980

11.8 kg (26 Ib)

15.9 kg

(35

Ib)

146 mm

(5.75

in.)

425 mm (16.8 in.)

462 mm (18.2 in.)

Conditions

48

to

66 Hz

48 to 440 Hz

Conducted and radiated interference

is

within the

requirements of methods

CEO3

and

RE02

of MIL STD 461B

and FTZ 526/527.

Conducted and radiated susceptiblity meets the requirements

of

methods CSO1,

CS02,

and

RS03

(1 volt/meter) of MIL STD 4618 dated 1980.

Net

Shipping

Note: For ordering cabinet accessories, the module sizes are

51/4H

x

1MW

x

17D.

Table

1-2

Supplemental Information

All parameters describe performance in automatic operation or with properly set manual controls.

MEASUREMENT

SINAD

Detection

true rms or rms calibrated average.

Resolution:

0.01 dB. For ratios less than 25 dB, Spe-

cial Function 16.0 will round the display to the

nearest half dB to reduce .digit flickering with noisy

signals.

Tuning:

notch filter is tuned to counted input

frequency.

Time

to

Return First Measurement:

1.5s

typical.

Measurement Rate:

2.0

readings/s typical.

3

dB Measurement Bandwidth:

10

Hz to 500 kHz.

Detection:

true rms or rms calibrated average.

Displayed Resolution:

DISTORTION

0.0001%

(<0.1%

distortion)

0.001

YO

(0.1

YO

to

3%

distortion)

0.01

YO

(3%

to

30%

distortion)

0.1

'10

(>30°/o

distortion)

Time

to

Return First Measurement:

1.5s

typical.

Measurement Rate:

2

reading+ typical.

AC Converter:

true rms responding for signals with

crest factor of

13

or rms calibrated average

detection.

AC LEVEL

AC

LEVEL (cont'd)

3

dB Measurement Bandwidth:

>500

kHz.

Time

to

Return First Measurement:

<1.5s typical.

Measurement Rate:

2.5 readings/s.

DC LEVEL

Time

to

Return First Measurement:

4.5s typical.

Measurement Rate:

3

readingls.

FREQUENCY MEASUREMENT

Measurement Rate:

same as measurement mode

Counting Technique:

reciprocal with 2 MHz time

selected.

base.

AUDIO FILTERS

400

Ht High-Pass Filter Rejection:

>40 dB at 240 Hz;

>65dB at 60Hz.

Monitor

Output

Output Impedance: 600fl.

In

ac level mode, provides scaled output of

measured input signal.

In

SINAD, distortion, and distortion level modes,

provides scaled output

of

input signal with the

fundamental removed.

1-

15

General Information

Critical Specifications

Accuracy: 0.5%, 7 mV

to

300V, 20

Hz

to

100

kHz

Flatness: ~0.1%, 20 Hr to 100 kHz, <6V

Output Current: 60 mA

Frequency Accuracy:

25%

Frequency Range:

20

Ht to

500

kHz

Frequency Accuracy: 54ppm

Output Range: 3V into 600Q

Output Attenuation Accuracy: 20.075 dB, to 0.3 mV range

HP-16 compatibility as defined by IEEE Std. 488 and the

identical ANSI Std. MC1.l: SHl, AH1, T2, TEO L2, LEO,

SRO,

PPO, DCO, DTO, and C1, 2, 3, 4,

5.

Output Range: 3 mV to 300V

Accuracy:

?0.1%

20.3 mV

Model

89033

Suggested Model

HP 745A and

HP 746A,

Datron 4200 or

Fluke 5200A

and Fluke

521 5A

HP 3336C

HP 9825A/

98034Al98213A

or HP85B Opt.

007

HP 7408 or

Datron 4000 or

Fluke 893AR

Instrument Type

Frequency: 0.1,

1,

2,

5,

or 10 MHz

Accuracy:

rl

ppm

Bandwidth: <3 dB down

0

to 10 MHz

Sensitivity:

5

mV per division minimum

Input Impedance:

1

MQ

Triggering: Internal and External

House Standard

HP 1740A

output: to 215v HP 6215A

Accuracy:

5

0.1 O/O HP 0698-7497

AC Calibrator

A

CAT

T

P

Audio Synthesizer

Computing

Controller

DC Standard

Digital Voltmeter

Frequency

Standard

Oscilloscope

Power Supply

Resistor 100kQ

Signature

Analyzer

Test Oscillator

True RMS

Voltmeter

AC Accuracy: r0.2% at 6 Vrms and

1

kHz

DC Accuracy: +0.2% at 1V

Because the signatures documented are unique to a given

signature analyzer type, no substitution

of

types is

recommended.

HP 5005A T

I

Frequency:

1

kHz

Output: 30 Vpp

I

HP

3310A

IT

I

Type: true rms responding

Level Range: 100 mV to

1OV

Frequency Range: 20 Hz to

500

kHz

Accuracy:

20.2%

of

range 50.2%

of

reading

Coupling: ac

HP 3403C P

I

1-16

Model

89033

General Information

Accessory

Extender Board

Digital Test/

Table

1-4.

Service Accessories

Specifications Suggested Model

No

substitution recommended HP

08903-6001 8

Extender Board

44

contacts

(2

X

22), 3

required

30

contacts

(2

X

15),

2

required

HP

08901 -60084

HP

08901 -60085

Foam Pad

NOTE

Conductive polyurethane foam,

12

x

12

X

0.25

inches (nonmagnetic) HP

4208-0094

The performance tests, adjustments, and troubleshooting procedures are based on the

assumption that the recommended test equipment

is

used. Substituting alternate test

equipment may require modification of some procedures.

1-17

Model

89033

Installation

Section

2

INSTALLATION

2-1.

INTRODUCTION

This section provides the information needed to in-

stall the Distortion Analyzer. Included is information

pertinent to initial inspection, power requirements,

line voltage and fuse selection, power cables, intercon-

nection, mating connectors, operating environment,

instrument mounting, storage, and shipment. In addi-

tion, this section also contains the procedure for set-

ting the internal HP-IB talk and listen address

switches.

2-2.

INITIAL INSPECTION

pZiiE-1

To avoid hazardous electrical shock, do

not perform electrical tests when there are

signs of shipping damage to any portion

of

the outer enclosure (covers, panels,

meters).

Inspect the shipping container for damage.

If

the

shipping container

or

cushioning material is damaged,

it

should be kept until the contents of the shipment

have been checked for completeness and the instru-

ment has been checked mechanically and electrically.

Procedures for checking electrical performance are

given in Section 4. If the contents are incomplete,

if there is mechanical damage

or

defect,

or

if

the

instrument does not pass the electrical performance

test, notify the nearest Hewlett-Packard office.

If

the

shipping container

is

damaged,

or

the cushioning ma-

terial shows signs of stress, notify the carrier as well

as the Hewlett-Packard office. Keep the shipping

materials for the carrier’s inspection.

2-3.

PREPARATION

FOR

USE

2-4.

Power Requirements

(WARNING

1

To avoid the possibility of hazardous elec-

trical shock, do not operate this instrument

at line voltages greater than

126.5

Vac

with line frequencies greater than

66

Hz.

Leakage currents at these line settings may

exceed

3.5

mA.

The Distortion Analyzer requires a power source of

100, 120, 220,

or

240 Vac, +5% to -lo%, 48 to

66

Hz single phase

or

100, 120 Vac, +5%

to

-lo%,

48

to

440

Hz

single phase. Power consumption is

100

VA

maximum.

This

is

a Safety Class I product (that

is,

provided with a protective earth terminal).

An

uninterruptible safety earth ground

must

be provided from the mains power

source to the product input wiring termi-

nals, power cord,

or

supplied power cord

set. Whenever

it

is

likely that the protec-

tion

has

been impaired, the product

must

be made inoperative and be secured against

any unintended operation.

If this instrument is to be energized via

an external autotransformer, make sure

the

autotransformer’s common terminal is

connected to the earthed pole of the power

source.

2-5.

Line Voltage

and

Fuse Selection

BEFORE PLUGGING THIS INSTRU-

MENT into the Mains (line) voltage, be

sure the correct voltage and fuse have been

selected.

Verify that the line voltage selection card and the

fuse are matched to the power source. Refer to Figure

2-1,

Line

Voltage and Fuse Selection.

Fuses may be ordered under

HP

part numbers 2110-

0059,

1.5A

(250V time delay) for 100/120 Vac opera-

tion and 2110-0018, 0.75A (250V, time delay)

for

220/240 Vac operation.

2-6.

Power Cables

I

WARNING

1

STRUMENT, the protective earth termi-

nals of this instrument

must

be connected

to

the

protective conductor of the (Mains)

power cord. The Mains plug shall only be

inserted

in

a socket outlet provided with

a protective earth contact. The protective

action must not be negated by the use

of

an extension cord (power cable) without a

protective conductor (grounding).

BEFORE CONNECTING THIS IN-

2-

1

Installation

This instrument is equipped with a three-wire power

cable. When connected to an appropriate ac power

receptacle, this cable grounds the instrument cabinet.

The type of power cable plug shipped with each

instrument depends on the country of destination.

Refer to Figure

2-2

for the part numbers of the power

cables available.

2-7.

HP-IB

Address

Selection

a

This task should be performed only by serv-

ice trained persons who are aware of the

potential shock hazard of working on an

instrument with protective covers

removed.

To

avoid hazardous electrical shock, the

line (Mains) power cable should be discon-

nected before attempting to change the

HP-IB

address.

In the Distortion Analyzer, the HP-IB talk and listen

addresses are selectable by an internal switch. The

Model 89033

following procedure explains how the switches are to

be set. Refer to Table

2-1

for a listing of the talk

and listen addresses. The address

is

factory set for

a Talk address of

"\"

and

a

listen address of

"<".

(In

binary, this

is

11100;

in decimal

it

is 28.)

To

change

the HP-IB address, the top cover of the Distortion

Analyzer must be removed.

a.

b.

Disconnect the line (Mains) power cable.

Remove any HP-IB cables or connectors from

the HP-IB connector.

c. Remove the Distortion Analyzer top cover.

1.

Remove the two plastic feet from the rear of

the top cover by removing the panhead Pozi-

driv screw within each foot.

2.

Unscrew the Pozidriv screw at the center

of

the rear edge of the top cover. This is a

captive screw and will cause the top cover to

pull away from the front frame.

3. Lift off the top cover.

To

avoid the possibility

of

hazardous electrical

shock, do not operate this instrument at line

voltages greater than 126.5 Vac with line fre-

quencies greater than 66

Hz

(leakage currents

at these line settings may exceed 3.5

mA).

Operating voltage

IS

shown in module window.

1.

Open cover door,

pull

the

FUSE

PULL

lever and rotate

to

left. Remove the

fuse.

2.

Remove

the

Line Voltage Selection Card. Position the card

so

the line voltage appears at top-left cover.

3.

Rotate the Fuse

Pull

lever to

its

normal position. Insert a fuse of the correct value

in

the holder. Close

Push

the card

firmly

into

the

slot.

the cover door.

Figure

2-1.

Line Voltage and Fuse Selection

2-2

Model

89033

8120-1351

8120-1703

Installation

0

6

8120-1369

8120-0696

0

4

8120-1689

8120-1692 7

2

8120-1378

8120-1398

8120-1754

8120-1378

8120-1521

8120-1676

5

7

1

6

2

8120-2104 3

8120-0698 6

8120-1957

8120-2956 2

3

8120-1860 6

Plug

Description

Cable

Length

(inches)

Cable

Color For Use

In Country

Cable

HP Part

Number

I

Straight'BS1363A

I

90

I

250v

Mint Gray

Mint Gray United Kingdom,

Cyprus, Nigeria,

Rhodesia,

Singapore

90" 90

1

250v

Gray

Gray Australia,

New Zealand

Straight'CEE7-Y11

90" 79

79 Mint Gray

Mint Gray

250v

@

East and West

Europe, Saudi

Arabia, Egypt,

So.

Africa, India

(unpolarized in

many nations)

United States,

Canada,

Japan (1OOV or

200V), Mexico,

Phillipines,

Taiwan

I

125V

Straight*NEMA&15P

90"

Straight'NEMA5-15P

90"

Straight'NEMA5-15P

80

36

80

36

Black

Jade Gray

fi

Straight'SEVl

01

1

Type 12

1959-24507 79 Gray Switzerland

250V

Straight'NEMA6-15P United States,

Canada

250v

a

no

I

220v

Gray

Gray Denmark

I

~

250v

Straight'CEE22-VI

(Systems Cabinet use)

'Part number shown for plug is industry identifier for plug only. Number shown for cable is HP Part Number for com-

plete cable including plug.

E

=

Earth Ground:

L

=

Line;

N

=

Neutral

Figure

2-2.

Power Cable and Mains Plug Part Numbers

2-3

Installation

00010

B

2

00011

C

#

3

d. Locate the HP-IB address switch accessable

through a hole near the center rear of the internal

shield cover.

Use a pencil to set the switches to the desired

HP-IB address and Talk Only

(TON)

or

Listen

Only (LON) condition. The switch

is

illustrated

in Figure

2-3.

Facing the board, the left hand

switch (marked with a

“5”)

is the most significant

address bit

(A5

in Table

2-1).

Setting a switch

toward the printed circuit board places it in its

“1”

position. If the TON and LON switches are

both set to

“l”,

the Talk Only setting will override.

If the address switches and the

TON

switch are

all set to

“l”,

the Distortion Analyzer will output

one byte (the status byte) each measurement

cycle. (Setting all switches to

“1”

defeats HP-IB

operation.)

e.

01100

L

12

13

01101

M

01110

N

14

-

Figure

2-3.

The HP-IB Address Switch Shown

as

Set

by

the Factory. The Address Shown

is

11100

in Binary with Both Talk

Only

and Listen Only

Off.

Reinstall the top cover by reversing the procedure

in step

c

above.

Connect the line (Mains) power cable to the Line

Power Module and reconnect the HP-IB cable

to the HP-IB connector.

h.

To confirm the setting, refer to HP-IB Address

in the

Detailed Operating Instructions

in

Section3 of this manual.

2-8.

Interconnections

Interconnection data for the Hewlett-Packard Inter-

face Bus

is

provided in Figure

2-4.

2-4

f.

g.

01111

0

I

15

10000

P

0

16

10001

Q

1

17

Model

89033

-Table

2-1.

Allowable HP-IB Address Codes

10010

R

2

18

10011

S

3

19

10100

T

4

20

10101

U

5

21

10110

V

6

22

11100

\

<

28

29

- -

11101

1

1111111101

n

>

1

30

0

Y

9

25

Z

26

27

Model

89033

Installation

Temperature

.....................

0°C

to

+55”C

Humidity

........................

<95%

relative

Altitude

.............

<4570

meters

(15

000

feet)

2-1 1. Bench Operation

The instrument cabinet has plastic feet and foldaway

tilt stands for convenience in bench operation. (The

plastic feet are shaped to ensure self-aligning of the

instruments when stacked.) The tilt stands raise the

front of the instrument for easier viewing of the front

panel.

2-12. Rack Mounting

1-1

The Distortion Analyzer is heavy for its

size

(11.8

kg,

26

lb). Care must be exercised

when lifting to avoid personal injury. Use

equipment slides when rack mounting.

DO NOT

BLOCK

the ventilation holes in

the bottom panel. Since this instrument

does not

use

a cooling fan, it is important

that good ventilation be provided.

Allow

for

1

to

2

inches clearance around the

bottom panel.

Rack mounting information is provided with the rack

mounting kits.

If

the kits were not ordered with the

instrument as options, they may be ordered through

the nearest Hewlett-Packard office. Refer

to

para-

graph

1-13,

Mechanical Options,

in Section

1.

2-13. STORAGE

AND

SHIPMENT

2-14. Environment

The instrument should be stored in a clean, dry

environment. The following environmental limita-

tions apply to both storage and shipment:

a.

b.

C.

d.

e.

Temperature

..................

-55°C

to

+75”C

Humidity

........................

<95%

relative

Altitude

.............

15

300

meters

(50

000

feet)

2-1

5.

Packaging

Original Packaging.

Containers and materials identi-

cal to those used in factory packaging are available

through Hewlett-Packard offices.

If

the instrument

is

being returned to Hewlett-Packard for servicing,

please fill out one of the blue tags located at the end

of this manual. Include on the tag the type of service

required, return address, model number, and full serial

number and attach

it

to

the instrument.

Mark

the

container “FRAGILE” to assure careful handling. In

any correspondence refer to the instrument by model

number and full serial number.

Other Packaging.

The following general instructions

should be used for re-packaging with commercially

available materials:

Wrap the instrument in heavy paper

or

plastic.

(If shipping to a Hewlett-Packard office

or

service

center, complete one of the blue tags mentioned

above

and

attach

it

to the instrument.)

Use a strong shipping container. A doublewall

carton made of

2.4

MPa

(350

psi)

test

material

is

adequate.

Use enough shock-absorbing material

(75

to

100

mm layer;

3

to

4

inches) around

all

sides

of

instrument

to

provide a firm cushion and prevent

movement in the container. Protect the front

panel with cardboard.

Seal the shipping container securely.

Mark the shipping container “FRAGILE

to

as-

sure careful handling.

2-5

Model

89033

Installation

SIGNAL GROUND SHIELD -CONNECT TO

P/O TWISTED PAIR WITH

11

ATN EARTH

P/O

TWISTED PAIR WITH

10

SRQ

GROUND

P/O TWISTED PAIR WITH

8

P/O TWISTED PAIR WITH

7

P/O TWISTED PAIR WITH

6

SHOULD BE GROUNDED P/O TWISTED PAIR WITH

9

IFC

NEAR TERMINATION

OF

OTHER WIRE

OF

TWISTED PAIR

NDAC

NRFD

DAV

EO1

Dl0

4

DIO 3

Dl0

2

DIO

1

ISOMETRIC

THREAD M3.5 24-PIN MICRO-RIBBON

(SERIES

57)

CONNECTOR

logic levels

The Hewlett-Packard Interface Bus logic levels are

TTL

compatible, that is, the true

(1)

state is

0.0

Vdc to

+0.4

Vdc and the false (0) state is 2.5 Vdc to +5 Vdc.

Programming and Output Data Format

Refer to Section 3, “Operation”.

Mating Connector

HP 1251 -0293; Amphenol 57-30240.

Mating Cables Available

HP 10631A, 1 meter (3.3

ft),

HP 10631B, 2 meters (6.6

ft)

HP 10631C,

4

meters (13.2

ft),

HP 10631D,

0.5

meters (1.6

ft)

Cabling Restrictions

1.

A

Hewlett-Packard Interface Bus system may contain no more than 2 meters (6.6

ft)

of

2. The maximum accumulative length of connecting cable for any Hewlett-Packard Interface Bus

connecting cable per instrument.

system

is

20 meters (65.6

ft).

Figure

2-4.

Hewlett-Packard Interface

Bus

Connection

2-6

Model

89033

Operation

Section

3

OPERATION

3-1.

INTRODUCTION

3-2.

General

This section provides complete operating information

for the Distortion Analyzer. Included in this section

are descriptions of all front and rear-panel controls,

connectors, and indicators, remote and local opera-

tor’s checks, operating instructions, and operator’s

maintenance.

3-3.

Operating Characteristics

Table

3-

1

briefly summarizes the major operating

characteristics of the Distortion Analvzer. The table

In single-ended (FLOAT switch

in

grounded position)

or

differential (FLOAT

switch in FLOAT position) operation, the

input signal voltage is not to exceed

300V

when referenced to ground, on the high

INPUT connector (inside conductor of the

BNC).

In differential (FLOAT switch

in

FLOAT

position) operation, the peak voltage on

the

low

INPUT connector (outer conductor

of

the BNC) is not to exceed

42V.

is not intended to be an in-depth listing of all opera-

tions and ranges but gives

an

idea of the instrument’s

capabilities.

For

more information on the Distortion

Analyzer capabilities, refer to the description in Sec-

tion

1;

Table

1-1,

Specifications;

and Table 1-2,

Sup-

Before the Distortion Analyzer is switched

on,

it

must

be set to the voltage of the

power source, or damage to the instrument

may result.

plemental Information.

For

information on

HP-IB

capabilities, refer to the summary contained in Table

3-3,

Message Reference Table.

A

3-4.

Turn-On Procedure

pziz-1

Before the Distortion Analyzer

is

switched

on, all protective earth terminals, extension

cords, auto-transformers, and devices con-

nected to it should be connected to a pro-

tective earth socket. Any interruption

of

the protective earth grounding will cause

a potential shock hazard that could result

in personal

injury.

In addition, verify that

a common ground exists between the unit

under test and the Distortion Analyzer

prior to energizing either

unit.

For continued protection against fire haz-

ard, replace the line fuse with a

250V

time

delay fuse of the same rating. Do not use

repaired fuses

or

short-circuited

fuseholders.

To avoid the possibility of hazardous elec-

trical shock, the input signal voltage on

the outer connector (referenced to ground),

is not to exceed

42V

peak

in

the FLOAT

mode.

If the Distortion Analyzer

is

already plugged in, set

the

LINE

switch

to

ON.

If the power cable

is

not

plugged in, follow these instructions.

1.

Check that the line voltage setting matches the

power source

(see

Figure

2-1).

2.

Check that the fuse rating is appropriate for the

line voltage used (see Figure

2-1).

Fuse Ratings

are given under paragraph

3-8,

Operator’s

Maintenance.

3.

Plug in the power cable.

4.

Set the

LINE

switch to

ON.

NOTE

When

the LINE switch

is

set to ON, all

front-panel indicators

will

light for approx-

imately

4

seconds after which the instru-

ment is ready to be operated.

3-5.

Local Operation

Information covering front-panel operation of the

Distortion Analyzer

is

given in the sections described

below.

To

rapidly learn the operation of the instru-

ment, begin with the Simplified Operation and Opera-

tor’s Checks. Once familiar with the general operation

of the instrument, use the Detailed Operating Instruc-

tions for in-depth and complete information on opera-

ting the Distortion Analyzer.

3-

1

Operation Model 89033

Simplified Operation.

Information on subsequent

pages under

Simplified Operation

provides a quick

introduction to front-panel operation of the

Distortion Analyzer. It is designed to rapidly orient

the novice user with basic procedures and, therefore,

is not an exhaustive listing of all Distortion Analyzer

functions. However, an index to the Detailed Opera-

ting Instructions appears in Table 3-2 to guide the

operator to the more complete discussion of the topic

of interest.

Panel Features.

Front-panel controls, indicators, and

connectors are illustrated and described in Figure 3-1.

This figure describes the functions of the various key

groups and summarize briefly how to use them. Rear-

panel features are shown in Figure 3-2.

Detailed Operating Instructions.

The Detailed Oper-

ating Instructions provide the complete operating

reference for the Distortion Analyzer user. The in-

structions are organized alphabetically by subtitle.

Not only do the instructions contain information on

the various measurements that can be made (listed

under titles such as AC Level, Distortion, etc.) but

there are also individual discussions of nearly all

controls, inputs, and outputs, (for example,

AVG/

RMS Detector, Monitor, etc.). Also included are in-

structions for using the many User Special Functions

(for example, Hold Settings,

Error

Disable, Special

Functions, etc.). The Detailed Operating Instructions

are indexed by function in Table 3-2.

Each section contains a general description which

covers signal levels, ranges, and other general informa-

tion. Following the description are related procedures,

an operating example, the relevant HP-IB codes, front

panel indications, and, where pertinent, a description

of the technique the Distortion Analyzer uses to make

the measurement.

At

the end of each discussion are

comments intended to guide the user away from

measurement pitfalls and to help get the most out

of

the Distortion Analyzer. Also included are refer-

ences to other sections which contain related informa-

tion. The Detailed Operating Instructions are de-

signed

so

that both casual and sophisticated users

can rapidly find at one location all the information

needed to apply the instrument to the task at hand.

Supplemental Information.

In addition to the infor-

mation described above, several other discussions per-

tinent to the operating of the Distortion Analyzer to

its fullest capabilities are contained in Section

1

of

this manual. Principles of Operation

for

a Simplified

Block Diagram is

a

fundamental description

of

what

the Distortion Analyzer is, and how it

works.

This

information supplements the block diagrams given in

the Detailed Operating Instructions and provides a

basis for applying the Distortion Analyzer to various

measurement situations. Basics of Audio Measure-

ments is a general discussion of audio measurements.

It

is

intended to provide an intuitive understanding

of audio measurements, rather than an in-depth math-

ematical analysis.

3-6.

Remote Operation

The Distortion Analyzer is capable of remote opera-

tion via the Hewlett-Packard Interface Bus (HP-IB).

Instructions pertinent to HP-IB operation cover all

considerations and instructions specific to remote op-

eration including capabilities, addressing, input and

output formats, the status byte, and service requests.

At

the end of the discussion is a complete summary

of all codes and formats.

In addition to the section described above, informa-

tion concerning remote operation appears in several

other locations.

HP-IB

Address selection is discussed

under paragraph 2-7 in Section

2.

Numerous examples

of program strings appear throughout the Detailed

Operating Instructions described under Local Opera-

tion above.

3-7.

Operator’s Checks

Operator’s checks are procedures designed to verify

the proper operation of the Distortion Analyzer’s

main functions.

Two

procedures are provided

as

de-

scribed below.

Basic Functional Checks.

This procedure requires

an

audio oscillator, oscilloscope, and inter-connecting

cables.

It

assumes that most front-panel controlled

functions are being properly executed by the

Distortion Analyzer.

HP-IB Functional Checks.

This series of procedures

requires an HP-IB compatible computing controller

and an HP-IB interface and connecting cable. The

HP-IB Functional Checks assume that front-panel

operation has been verified (for example, by perform-

ing the Basic Functional Checks). The procedures

check all of the applicable bus messages summarized

in Table 3-3.

3-8.

Operator’s Maintenance

pG-1

For continued protection against fire haz-

ard, replace the line fuse with a

250V

time

delay fuse

of

the same rating

only.

Do

not

use repaired fuses

or

short-circuited

fuseholders.

3-2

Operation

Model

89033

~ ~ ~~

Measurements

(including counter frequency

measurements except in

DC Level)

Detection

r

The only maintenance the operator should normally

perform is the replacement

of

the primary power fuse

located within the Line Power Module

(A14).

For

instructions on

how

to change the fuse, refer to Figure

2-1 steps

1

and

3

in Section 2,

Installation.

Fuses may be ordered by looking up the reference

designator

F1

in Section

6,

Replaceable Parts,

and

ordering the correct part number for 100/120 Vac

or

for 2201240 Vac operation (both fuses are 250V time

delay).

NOTE

If

the instrument does not operate properly

and is being returned to Hewlett-Packard

for

service, please complete one

of

the blue

repair tags located at the end of this man-

ual

and

attach it to

the

instrument. Refer

to paragraph

2-15

in Section

2

for

packag-

ing instructions.

Table

3-1.

Operating Characteristics Summary

Operating Parameter

Input

Limits

Audio

Filters

Manual Operation

CaDa

bilities

Frequency:

20

Hz

to

100

kHz

(150

kHz, AC Level)

Level:

=O

to 300V ac or dc.

Impedance:

100

kQ (except DC Level);

101

kQ (DC Level); floating input can

be selected.

AC LEVEL:

=O

to 300 Vac;

20

Hz to

150

kHz. Full range display from

DC LEVEL

0

to 300 Vdc. Full range display from 4.000V to 300.0V in four ranges.

SINAD:

50

mV to 300V;

20

Hz to

100

kHz. Display range

0

to 99.99 dB.

DISTN: 50 mV to 300V; 20 Hz to 100 kHt. Display range -99.99 to

0

dB.

True rms or average detection.

HP/BP FILTER-Up to

two

of

the following HP/BP filters may be installed:

.3000 mV to 300.0V in seven ranges.

HIGH PASS 400 Hz: 400 240

Hz

(3 dB cutoff)

CCllT Weighting: Recommendation P53.

CClR Weighting: CClR 468-2,

DIN

45405

A-Weighting: ANSI S1.4, IEC rec 179, DIN 45633

CCIR/ARM Weighting: Dolby Labs

C-MESSAGE: BSTM #41009 FIG

1

LP FILTER

LOW PASS

30 kHz: 30

22

kHz (3 dB cutoff).

80 kHz: 80 24 kHz (3 dB cutoff).

Average and rrns detection, notch tune, ratio, log/linear, filter selection and

measurement selections can be manually controlled.

All

Distortion Analyzer operations except the LINE and FLOAT switches can

be controlled via the Hewlett-Packard Interface Bus.

3-3

Operation

Model

8903E

2 3

4

5

67

8

9

1

10

17

16

1.

HP-IB

Annunciators indicate remote operation

status.

2.

LCL

(local) key returns the Distortion Analyzer to

keyboard control from remote (HP-IB) control.

3.

Frequency Display

Annunciators indicate the

frequency units.

4.

MEASUREMENT CYCLE

Indicator blinks after each

measurement cycle.

5.

The

two

Numeric Displays

show

the frequency,

measurement results, error codes, or instrument

or

Special Function status.

measurement result units.

6.

Measurement Display

Annunciators indicate the

7.

RATIO

key causes measurements to be displayed

8.

LOG/LIN

key causes results to be displayed in loga-

9.

MEASUREMENT

keys command the Distortion

in

%

or dB relative to a reference.

rithmic or linear units.

Analyzer to make and display the selected

measurement.

10.

INPUT

couples measurement signal into the instru-

ment.

1

15

14

13

12

11

FLOAT

switch provides floating input when

required.

12.

LOW

PASS

30 kHz and

80

kHz filters reject high

frequency noise.

13.

RIGHT-MOST OPTIONAL PLUG-IN FILTER

key se-

lects the filter that is installed in the right-most filter

slot. The C-Message Weighting (bandpass) Filter

(Option

053)

shown weights receiver testing accord-

ing to BSTM

41004.

14.

LEFT-MOST OPTIONAL PLUG-IN FILTER

key selects

the filter that is installed in the left-most filter slot.

The CClR Weighting (bandpass) Filter (Option 012)

shown weights receiver testing according

to

CCIR

Recommendation

468-2,

DIN

45405.

15.

NOTCH TUNE

key switches the Notch Filter tune

control between Auto Tuned and Hold mode (locking

the Notch Filter at its current frequency setting).

16.

MONITOR OUTPUT

in ac level mode, provides a

scaled voltage output representing the input signal.

In SINAD, distortion, and distortion level modes,

provides

a

scaled voltage output of the input signal

with fundamental removed. Output impedance is

6009.

17.

LINE

switch applies power

to

the Distortion Analyzer

when set

to

ON.

Figure

3-1.

Front-Panel Features

3-4

Model

89033

RATIO

on

I

LOG

I

Operation

RATIO

ofl

LOG

LIN

SI

M

PLI

F

I

ED OPE RATION

Measurement

AC

or

For ac level or distortion measurements, press:

fi

Filters

I

HP/BP

Filter

Corresponding

Fllter

To

activate any

of

the optional plug-in filters, press:

[.I

LOW

PASS

30

kH2

LP

Filter

To

activate the

LOW

PASS

30

kHz

filter, press:

I.1

RATIO and LOG/LIN

RATIO

To

set the displayed measurement as the ratio reference, press:

wno

.

0

LOG/LIN

To convert from linear to logarithmic (or from logarithmic to linear) measurement units, press:

o(@>

.

Measurement

I

Mode

1-

dBm into 600Q

dBm into

600Q

I

AC

LEVEL

V

or mV

I

--

I

NOTE

Duringpower

up,

the Distortion Analyzer

is

initialized and set to automatic operation.

3-5

Operation

Model

89033

Table

3.2

.

Detailed Operating Instructions Table

of

Contents (Functional Listing)

Section

Page

Measurements

AC Level

...........................

3-33

Common Mode

......................

3-36

DC Level

...........................

3-39

Detector Selection

....................

3-41

Distortion

...........................

3-43

controlled only)

.....................

3-45

SINAD

..............................

3-78

Distortion Level (HP-IB

Filters

Filters (Low.Pass.

High.Pass. Bandpass)

...............

3-51

Notch Tune

.........................

3-67

Post-Notch Detector Filtering

...........

3-68

Data Manipulation

Display Level in Watts (HP-IB

Hold Decimal Point (HP-I6

controlled only)

.....................

3-42

controlled only)

.....................

3-57

Ratio and Log/Linear

.................

3-73

Errors

Error Disable

........................

3-47

Error Message Summary

..............

3-48

Inputs and Outputs

Float

...............................

3-55

Monitor

.............................

3-64

Section

Page

Special Functions

Detector Selection

....................

3-41

controlled only)

.....................

3-42

Display Level in Watts (HP-IB

Error Disable

........................

3-47

Hold Decimal Point (HP-IB

controlled only)

.....................

3-57

Hold Settings (HP-IB controlled only)

....

3-58

HP-IB Address

.......................

3-59

controlled only)

.....................

3-61

(HP-IB controlled only)

..............

3-62

Notch Tune

.........................

3-67

(HP-IB controlled only)

..............

3-68

controlled only)

.....................

3-75

controlled only)

.....................

3-76

controlled only)

.....................

3-80

controlled only)

.....................

3-86

Input Level Range (DC Level) (HP-IB

Input Level Range (Except DC Level)

Post-Notch Detector Filtering

Post-Notch Gain (HP-IB controlled only)

.

3-69

Read Display to HP-IB (HP-IB

Service Request Condition (HP-IB

Special Functions (HP-IB

Time Between Measurements (HP-IB

HP-IB

HP-IB Address

.......................

3-59

Read Display to HP-I6

................

3-75

Rapid Frequency Count

...............

3-70

Service Request Condition

.............

3-76

Miscellaneous

Automatic Operation .................. 3-35

Power-Up Sequence

................

3-40

Float

...............................

3-55

Default Conditions and

3-6

Mode1

89033

Operation

HP-IB Connector

connects the Distortion Ana-

lyzer

to

the Hewlett-Packard Interface

Bus

for

remote operations. When in remote mode, the

front-panel

REMOTE

annunciator lights.

\

Fuse.

1.50A (250V, time delay) for 100/120 Vac.

0.75A

(250V, time delay) for 220/240

Vac.

/

Serial Number Plate.

First

four

numbers and

letter comprise the prefix that denotes the in-

strument configuration. The last five digits form

the suffix that is unique

to

each instrument.

Line Power Module

permits operation

from

100,

120, 220,

or

240

Vac. The number visible

in window indicates nominal tine voltage

to

which instrument must be connected (see Fig-

ure 2-1). Center conductor is safety earth ground.

1

3-7

Figure

3-2.

Rear Panel Features

Operation

INPUT

~~

onno

0

U

0

€%?on

IO

00

0

Model 89033

OPERATOR’S CHECKS

OUTPUT

AUDIO

INPUT

-

OSC

I

LLATOR

I

3-9

OPERATOR’S CHECKS

3-10.

Basic Functional

Checks

DESCRIPTION Using only an oscilloscope and an audio oscillator, the overall operation

of

the Distortion

Analyzer is verified.

OSClLLOSCOPE

In

I

D

I

STORT

8903E

ION

ANAL

.YZER

~

II

I I

VERTICAL

I

Figure

3-3.

Basic

Functional Checks Setup

EQUIPMENT Audio Oscillator

........................

HP339A or HP 8903B

Oscilloscope

.......................................

HP1740A

PROCEDURE:

Preliminary

Check

1.

Remove any cables

from

the Distortion Analyzer’s INPUT. Set the LINE switch

to

OFF,

and then back

to

ON and note

that

the front-panel LED annunciators,

display segments and decimal points, and key lights turn on. All LEDs should light

for approximately three seconds.

2.

After the turn-on sequence, the left display should show

0.000

kHz

and the right

display should show a low flickering value in mV. In addition, the measurement

cycle annunciator in the upper left-hand corner of the right display should be blinking

and the AC

LEVEL

and LOW

PASS

80

kHz keys should light.

3.

Connect the audio oscillator output

to

the INPUT of the Distortion Analyzer with

a BNC-to-BNC cable. Set the FLOAT switch

to

the ground position. See Figure

3-3.

4. Connect the oscilloscope

to

the MONITOR output. See Figure

3-3.

5.

Set the audio oscillator

to

1

Vrms

at

1

kHz. The left display should show the

frequency of the audio oscillator,

at

approximately

1

kHz. The right display should

show the amplitude

of

the audio oscillator, at approximately

1V.

The oscilloscope

should show a

1

kHz

(1

ms period) sine wave

of

approximately

7

Vpp.

6.

Press the RATIO key. The RATIO light should light. The right display should show

100%.

NOTE

In this and the following

steps,

the displays

may

vary

a few least-significant

digits.

7.

Press the AVG/RMS key. The AVG/RMS key should light. The right display should

remain at approximately 100%.

Model

89033

Oscillator Frequency

(Hz)

300

800

3

000

3

500

5

000

Operation

OPERATOR’S

CHECKS

Ratio limits (dB)

-12.1

to

-9.1

-0.4

to

+0.4

-7.1

to

-4.1

-11.5

to

-5.5

-40.0

to

-32.0

8.

Press the AVG/RMS key. The AVG/RMS key should light. Set the FLOAT switch

to FLOAT. The right display should remain at approximately 100%.

Oscillator Frequency

(Hz)

31.5

200

6

300

7 100

10

000

20

000

9.

Set the FLOAT switch back to ground. Press the LOG/LIN key. The right display

should show

0.00

dB.

Ratio Limits (dB)

1

-31.4

to

-28.4

-14.5

to

-13.1

+12.0

to

+12.4

+11.7

to

+12.3

+7.5

to

+8.7

-23.7

to

-20.7

Filter

Check

10.

11.

12.

13.

14.

Adjust the frequency (but not the level) of the audio oscillator

(to

approximately

80

kHz) until the right display reads

-3

dB.

The left display should show between

72

and

88

kHz.

Press the LOW

PASS

30 kHz key. The LOW

PASS

30 kHz key light should light.

Adjust the frequency (but not the level) of the audio oscillator (to approximately 30

kHz) until the right display reads -3

dB.

The left display should show between

26

and 34 kHz.

Press the LOW

PASS

30 kHz key again to turn it off. Set the audio oscillator to

100 kHz. The right display should show between

-1

and

1

dB.

If the instrument has option 010

or

050

installed, press 400

Hz

HIGH

PASS.

The

400

Hz

HIGH PASS key light should light. Adjust the frequency of the audio

oscillator (to approximately 400

Hz)

until the right display reads -3

dB.

The left

display should show between 360 and 440Hz.

Press the filter key listed in the following table for the filter option installed in the

instrument. The respective key light should light.

For

each filter, set the audio

oscillator frequency as shown in the following tables. Verify that the level ratio in

the right display is within the limits shown for each frequency.

3-9

Operation

Oscillator Frequency

(Hz)

100

500

1

000

3

000

5

000

Model 89033

OPERATOR’S

CHECKS

Ratio limits

(dB)

-44.0

to

-41.0

-9.0

to

-6.0

-0.2

to

+0.2

-4.0

to

-1.0

-30.0

to

-27.0

Table for C-Message Weighting Filter (Option

013

or

053)

Oscillator Frequency

(Hz)

31.5

200

6 300

7

100

10

000

20

000

Ratio Limits

(dB)

-37.0

to

-34.0

-20.1

to

-18.7

+6.4

to

1-6.8

+6.1

to

+6.7

11.9

to

+3.1

-29.3

to

-26.3

Table for

CCIRIARM

Weighting Filter (Option

014

or

054)

Oscillator Frequency

(Hz)

50

200

1

000

2

000

10

000

20

000

Ratio Limits

(dB)

-30.9

to

-29.5

-11.7

to

-10.3

-0.2

to

+0.2

+0.5

to

+1.9

-3.2

to

-1.8

-10.8

to

-7.8

Distortion Check

15. Set all filters

on

the Distortion Analyzer off. Press the

LOW

PASS 80 kHz key.

Press the DISTN key. The DISTN key light should light.

Set the audio oscillator frequency to

1

kHz. The right display should show 0.01%

or

less.

16.

SINAD

Check

17. Press the

S

(Shift) SINAD keys. The SINAD key light should light. The right

display should show 80

dB

or

more.

Press the Notch Tune key. The NOTCH TUNE

KEY

light should light.

Set the audio oscillator frequency to 890 Hz. The right display should show between

12

and 19

dB.

18.

19.

DC Level

Check

20.

Press the

S

(Shift) and DC LEVEL keys. The DC Level light should light. The

right display should show between -10 and 10mV. (With an ac voltage applied to

the input, the reading will not be steady.)

3-10

Model 89033

OPERATOR’S CHECKS

Operation

3-1

1.

HP-I6

Functional Checks

DESCRIPTION: The following ten procedures check the Distortion Analyzer’s ability to process

or

send

all

of

the applicable HP-IB messages described in Table

3-3.

In addition, the Distortion

Analyzer’s ability to recognize its HP-IB address is checked and all of the bus

data,

handshake, and control lines except D108 (the most significant

data

line which

is

not

used by the Distortion Analyzer)

are

set to both their true and false

states.

These

procedures do not check whether

or

not

all

Distortion Analyzer program codes are being

properly interpreted and executed by the instrument, however, if the front-panel operation

is good, the program codes, in all likelihood will be correctly implemented.

The validity

of

these checks

is

based on the following assumptions:

The Distortion Analyzer performs properly when operated via the front-panel keys

(that is, in local mode). This can be verified with the Basic Functional Checks.

The bus controller properly executes HP-IB operations.

The bus controller’s HP-IB interface properly executes the HP-IB operations.

If the Distortion Analyzer appears to fail any

of

these HP-IB checks, the validity of the

above assumptions should be confirmed before attempting to service the instrument.

The select code of the controller’s HP-IB interface

is

assumed to be

7.

The address

of

the Distortion Analyzer is assumed

to

be

28

(its

address

as

set

at

the factory). This select

code-address combination (that is, 728) is not necessary for these checks to be

valid.

However, the program lines presented here would have to be modified

for

any other

combination.

These checks are intended to be as independent of each other as possible. Nevertheless,

the first four checks should be performed in order before other checks are selected. Any

special initialization

or

requirements for a check are described at its beginning.

INITIAL

SETUP: The test setup

is

the same

for

all

of

the checks. Connect the Distortion Analyzer to the

bus controller via the HP-IB interface. Do not connect any equipment

to

the Distortion

Analyzer’s INPUT.

EQUIPMENT: HP-IB Controller

.

. . . .

HP 9825A/98213A (General and Extended

1/0

ROM)

-or-

HP 85B option

007

-or-

HP 9000 Model 226

or

any HP 9000 series 200 Computer

Address Recognition

NOTE This check determines whether

or

not the Distortion Analyzer recognizes when it is being

addressed and when it is not. This check assumes only that the Distortion Analyzer can

properly handshake on the bus. Before beginning this check, set the Distortion Analyzer’s

LINE switch to OFF, then

to

ON.

3-11

Operation

Description

Set the Remote Enable

(REN)

bus

control

line false.

Send the Distortion Analyzer’s listen address.

Model 89033

HPL

BASIC

IC1

7

LOCAL

7

wrt

728

OUTPUT

728

OPERATOR’S CHECKS

Unaddress the Distortion Analyzer

by

send-

ing a different address.

wrt

729

OUTPUT

729

OPERATORS

RESPONSE DRESSED annunciator is on.

Check that the Distortion Analyzer’s REMOTE annunciator is off and that

its

AD-

~ ~~

Send the Remote message

(by

setting Re-

mote Enable,

REN,

true and addressing the

Distortion Analyzer to listen).

rem

728

REMOTE

728

OPERATOR’S

RESPONSE are off.

Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

Send the Local message to

the

Distortion

Analyzer.

Remote and Local Messages and the LCL

Key

Id

728

LOCAL

728

NOTE This check determines whether the Distortion Analyzer properly switches from local to

remote control,

from

remote to local control, and whether the LCL key returns the

instrument

to

local control. This check assumes that the Distortion Analyzer

is

able

to

both handshake and recognize

its

own address. Before beginning this check, set the

Distortion Analyzer’s LINE switch to

OFF,

then

to

ON.

Send the Remote message

to

the Distortion

Analyzer. rem

728

REMOTE

728

OPERATOR’S

RESPONSE are on.

Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

OPERATORS

RESPONSE annunciator is on.

Check that the Distortion Analyzer’s REMOTE annunciator is off but its ADDRESSED

OPERATOR’S

RESPONSE Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

are on. Press the LCL key on the Distortion Analyzer. Check that the Distortion Analyzer’s

REMOTE annunciator is now off, but that its ADDRESSED annunciator remains on.

3-12

Model 89033

Description

Address the Distortion Analyzer to

talk

and

store its output data in variable

V.

(The out-

put is

E96

since there is no signal at its INPUT.)

Display the value

of

V.

OPERATOR’S

CHECKS

HPL

BASIC

red 728,V ENTER 728;V

dsp

V

PRINT

V

Operation

Description

Send the first part

of

the Remote message

(enabling the Distortion Analyzer to remote).

Sending the Data Message

HPL

BASIC

rem 7 REMOTE 7

NOTE

Address the Distortion Analyzer to listen

(completing the Remote message), then

send

a

Data message (selecting the

Distortion measurement).

This check determines whether

or

not the Distortion Analyzer properly issues Data

messages when addressed to talk. This check assumes that the Distortion Analyzer

is

able to handshake and recognize its own address. Before beginning this check, set the

Distortion Analyzer’s LINE switch

to

OFF,

then to ON, then after the power-up sequence

is complete, press the DISTN key.

wrt

728,“M3 OUTPUT 728;“M3”

OPERATOR’S

RESPONSE Check that the Distortion Analyzer’s REMOTE annunciator

is

off but that

its

AD-

DRESSED annunciator is on. The controller’s display should read 9009600000.00 (HPL)

or

9009600000 (BASIC).

Receiving the Data Message

NOTE This check determines whether

or

not the Distortion Analyzer properly receives Data

messages. The Data messages sent also cause the

7

least significant HP-IB

data

lines to

be placed in both their true and false states. This check assumes the Distortion Analyzer

is

able to handshake, recognize

its

own

address and properly make the remote/local

transitions. Before beginning this check, set the Distortion Analyzer’s LINE switch

to

OFF,

then to

ON.

OPERATOR’S

RESPONSE Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

are on. Check also that

its

Distortion key light

is

on.

Local Lockout and Clear Lockout/Set Local Messages

NOTE This check determines whether

or

not the Distortion Analyzer properly receives the Local

Lockout message, disabling all front-panel keys. The check also determines whether

or

not the Clear Lockout/Set Local message is properly received and executed by the Distortion

Analyzer. This check assumes that the Distortion Analyzer is able to handshake, recognize

its own address, and properly make the remote/local transitions. Before beginning this

check, set the Distortion Analyzer’s LINE switch to

OFF,

then to ON.

3-

13

Operation

Description

Send the

first

part

of

the Remote message

(enabling the Distortion Analyzer to remote).

Send the Local Lockout message.

Model

89033

OPERATOR’S

CHECKS

7

HPL

BASIC

rem

7

REMOTE

7

I10

7

LOCAL

LOCKOUT

7

OPERATOR’S

RESPONSE

Address the Distortion Analyzer to listen

(completing the Remote message).

OPERATOR’S

RESPONSE

wrt

728

OUTPUT

728

Clear

Message

Send the Clear Lockout/Set Local message.

NOTE

IC1

7

LOCAL

7

OPERATOR’S

RESPONSE

Description

Send the first part

of

the Remote message

(enabling the Distortion Analyzer

to

remote).

Address the Distortion Analyzer to listen

(completing the Remote message), then

send a Data message that selects the

Distortion measurement.

OPERATORS

RESPONSE

HPL

rem

7

wrt

728,”M3

Send

the

Clear message (setting the

Distortion Analyzer’s measurement to

AC

LEVEL).

clr 728 RESET 728

Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

are on. Press the Distortion Analyzer’s LCL key. Both

its

REMOTE and ADDRESSED

annunciators should remain on.

Check that the Distortion Analyzer’s REMOTE annunciator

is

off

but its ADDRESSED

annunciator is on.

This check determines whether

or

not the Distortion Analyzer properly responds

to

the

Clear message. This check assumes that the Distortion Analyzer is able

to

handshake,

recognize

its

own address, make the remote/local changes and receive Data messages.

Before beginning this check set the Distortion Analyzer’s LINE switch to

OFF,

then to

ON.

BASIC

REMOTE

7

OUTPUT 728;”M3”

Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

are on and that the Distortion key light is also on.

Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

are on and that the AC LEVEL key light is on.

~

3-14

Model 89033

Description

HPL

Send

the Remote message to

the

Distortion

Analyzer.

rem

728

OPERATOR’S CHECKS

BASIC

REMOTE

728

Operation

Send

the

Abort message, unaddressing

the

Distortion Analyzer to listen. cli

7

~~~~ ~

Abort

Message

NOTE

ABORT10

7

This check determines whether or not the Distortion Analyzer becomes unaddressed when

it

receives the Abort message. This check assumes that the Distortion Analyzer

is

able

to handshake, recognize its own address, make the remote/local changes, and enter serial

poll mode. Before beginning this check, set the Distortion Analyzer’s LINE switch to

OFF,

then to ON.

Send

the Abort message, unaddressing

the

Distortion Analyzer to talk. cli

7

ABORT10

7

OPERATORS

RESPONSE are on.

Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

OPERATORS

RESPONSE Check that the Distortion Analyzer’s ADDRESSED annunciator

is

off. Note that the

BASIC “ABORTIO” statement sends both the Abort message and the Local message.

Thus

if

HPL

is

being used, the Distortion Analyzer’s REMOTE annunciator should

remain on.

If

BASIC

is

being used, the Distortion Analyzer’s REMOTE annunciator

should turn off.

Send

the

Local message

(HPL

only).

Address

the

Distortion Analyzer

to

talk and

store

its

output data

in

variable

V.

IC1

7

red

728.V

(The Local message was

already

sent

with

the

ABORT10

7

statement

above.)

ENTER

728:V.

OPERATOR’S

RESPONSE DRESSED annunciator is on.

Check that the Distortion Analyzer’s REMOTE annunciator is off but that its AD-

OPERATOR’S

RESPONSE off.

Check that both the Distortion Analyzer’s REMOTE

an

ADDRESSED annunciators are

3-15

Operation

a

Send

the

serial poll-enable bus command

(SPE) through the interface to place the

Distortion Analyzer in serial-poll mode.

Send Special Function 61.3

Model 89033

OPERATOR’S CHECKS

wti 0,7; wti 6,24 SENDBUS 728; 1,24

wrt

728,”61.3SP” OUTPUT 728; “61.3SP

Send the Abort message, removing the

Distortion Analyzer from serial-poll mode.

OPERATOR’S

RESPONSE On the Distortion Analyzer, the right display should show

1.0.

This indicates the Distortion

Analyzer

is

in serial-poll mode (indicated by the

“1”).

cli 7 ABORT10 7

Description

Place the Distortion Analyzer in serial-poll

mode and address it to talk (causing it to

send the Status Byte message).

Display the value of V.

OPERATORS

RESPONSE Check that the Distortion Analyzer’s right display shows

0.0.

This indicates the Distortion

Analyzer properly left serial-poll mode upon receiving the Abort message.

Status

Byte

Message

HPL

BASIC

rds (728)

-

V

STATUS 728;V

dsp V PRINT

V

NOTE

Send the Remote message.

This check determines whether or not the Distortion Analyzer sends the Status Byte

message in both the local and remote modes. This check assumes that the Distortion

Analyzer is able

to

handshake, recognize its own address, and make the remote/local

changes. Before beginning this check, set the Distortion Analyzer’s LINE switch to

OFF,

then to ON.

rem 728 REMOTE 728

1

Place the Distortion Analyzer in serial-poll

mode and address it to talk (causing it to

send the Status Byte message).

OPERATORS

RESPONSE Check that Distortion Analyzer’s REMOTE annunciator

is

off. Depending upon the

vintage

of

the HP-IB interface (HPL) used, the Distortion Analyzer’s ADDRESSED

annunciator may be either on

or

off. The controller’s display should read

0.00

(HPL)

or

0

(BASIC).

rds (728)

-

V

Display

the

value of V. dsp V PRINT V

STATUS 728;V

3-16

Model 89033

OPERATOR’S

CHECKS

Operation

a

Require Service Message

NOTE This check determines whether

or

not the Distortion Analyzer can issue the Require

Service message (set the SRQ bus control line true). This check assumes that the Distortion

Analyzer

is

able to handshake, recognize

its

own address, make the remote/local changes,

and receive Data messages. Before beginning this check, set the Distortion Analyzer’s

LINE switch to

OFF,

then to ON, then after the power-up sequence is complete, press

the DISTN key.

Description

Send

the

first

part of the Remote message

(enabling

the

Distortion Analyzer to remote).

Address

the Distortion Analyzer to listen

(completing

the

Remote message) then

send

a Data message (enabling a Require Service

message to

be

sent upon Instrument Error).

Make the controller wait

2

seconds to allow

time

for

the

Distortion Analyzer to send the

Require

Service message.

(This

step

is

not

necessary

if

sufficient time

is

allowed.)

Read the binary status of the controller’s

HP-IB interface and store the data

in

varia-

ble V

(in

this

step,

7

is

the interface’s select

code).

Display

the

value of the

SRQ

bit

(in

this

step,

7

is

the SRQ

bit,

numbered from

0).

HPL

rem

7

wrt

728.”22.4SP

wait

2000

rds

(7)

-

V

dsp“SRQ=”,

bit

(7 7V)

BASIC

REMOTE

7

OUTPUT

728;“22.4SP

WAIT

2000

STATUS

7; V

PRINT “SRQ=”;BIT

(V,7)

OPERATORS

RESPONSE

Service message.

Check that the SRQ value

is

1,

indicating the Distortion Analyzer issued the Require

Trigger Message and Clear Key Triggering

NOTE This check determines whether

or

not the Distortion Analyzer responds to the Trigger

message and whether the CLEAR key serves as a manual trigger in remote. This check

assumes that the Distortion Analyzer is able to handshake, recognize its own address,

make the remote/local changes, and send and receive Data messages. Before beginning

this check, set the Distortion Analyzer’s LINE switch to

OFF,

then to ON, then, when

the power-up sequence is complete, press the DISTN key.

3-17

Operation

a

Address the Distortion Analyzer to talk and

I

store the data

in

variable

V.

Model 89033

OPERATOR’S

CHECKS

red

728,V

I

~ ENTER~~~:V-~

Description

Send the

first

part

of

the Remote message

(enabling the Distortion Analyzer to remote).

Address the Distortion Analyzer to listen

(completing the Remote message), then

send a Data message (placing the Distortion

Analyzer

in

Hold mode).

Send the Trigger message.

Address the Distortion Analyzer to talk and

store the data

in

variable

V.

Display the value

of

V.

HPL

rem

7

wrt

728,

“Tl”

trg

728

red

728,

V

dsp

V

~~~

REMOTE

7

OUTPUT

728;

“Tl”

TRIGGER

728

ENTER

728;V

PRINT

V

OPERATORS

RESPONSE Check that both the Distortion Analyzer’s REMOTE and ADDRESSED annunciators

are on. The controller’s display should read 9009600000.00 (HPL)

or

9009600000 (BASIC).

OPERATOR’S

RESPONSE Check that the controller’s “run” indicator is still on indicating that it has not received

data from the Distortion Analyzer. Press the Distortion Analyzer’s

S

(Shift) AVG/RMS

keys (instrument clear). The controller’s “run” indicator should turn off.

3-18

Model 89033 Operation

3-12. REMOTE OPERATION, HEWLETT-

PACKARD INTERFACE

BUS

The Distortion Analyzer can be operated through the

Hewlett-Packard Interface Bus (HP-IB). Bus compat-

ibility, programming, and data formats are described

in the following paragraphs.

Except for the LINE switch, the low terminal ground/

FLOAT switch, and the Controller Reset Service Spe-

cial Function, all Distortion Analyzer operations (in-

cluding service related functions) are fully

programmable via HP-IB. In addition, rapid

frequency count capabilities (not available from the

front-panel) are provided in remote operation.

All

the Special Functions and the distortion level

measurement mode are available only through HP-IB

control.

A

quick test of the HP-IB

1/0

is described under

HP-IB Functional Checks. These checks verify that

the Distortion Analyzer can respond

to

or

send each

of the applicable bus messages described in Table 3-3.

For more information about HP-IB, refer to IEEE

Standard

488,

ANSI Standard MC1.1, the Hewlett-

Packard Electronic Systems and Instruments catalog,

and the booklet, “Improving Measurements in Engi-

neering and Manufacturing” (HP part number

5952-0058).

3-13. HP-IB Compatibility

The Distortion Analyzer’s complete bus compatibility

(as defined by IEEE Standard

488,

and the identical

ANSI Standard MC1.l) is described at the end of

Table 3-3. Table 3-3 also summarizes the Distortion

Analyzer’s HP-IB capabilities in terms

of

the twelve

bus messages in the left-hand column.

3-14. Remote Mode

Remote Capability.

In remote, most of the Distortion

Analyzer’s front-panel controls are disabled (excep-

tions are the LCL key and the Clear Key Function,

S

(Shift) AVG/RMS). However, front-panel displays

and the signal at various outputs remain active and

valid. In remote, the Distortion Analyzer may be

addressed to talk

or

listen. When addressed to listen,

the Distortion Analyzer will respond to the Data,

Trigger, Clear (SDC), and Local messages. When ad-

dressed to talk, the Distortion Analyzer can issue the

Data and Status Byte messages. Whether addressed

or

not, the Distortion Analyzer will respond

to

the

Clear (DCL), Local Lockout, Clear Lockout/Set

Local, and Abort messages, and in addition, the

Distortion Analyzer may issue the Require Service

message. Local-to-Remote Mode Changes. The

Distortion Analyzer switches to remote operation

upon receipt

of

the Remote message. The Remote

message has two parts. They are:

Remote enable bus control line (REN) set true

Device listen address received once (while REN is

true)

When the Distortion Analyzer switches to remote,

both the REMOTE and ADDRESSED annunciators

on

its

front panel will turn on.

3-15.

Local

Mode

Local Capability.

In local, the Distortion Analyzer’s

front-panel controls are fully operational and the in-

strument will respond to the Remote message.

Whether addressed

or

not,

it

will also respond to the

Clear, Local Lockout, Clear Lockout/Set Local, and

the Abort messages. When addressed to talk, the

instrument can issue Data messages and the Status

Byte

message, and whether addressed or not,

it

can

issue the Require Service message.

Remote-to-Local Mode Changes.

The Distortion

Analyzer always switches to local from remote when-

ever

it

receives the Local message (GTL)

or

the Clear

Lockout/Set Local message. (The Clear Lockout/Set

Local message sets the Remote Enable control line

[REN] false.) If

it

is

not in Local Lockout mode, the

Distortion Analyzer switches

to

local from remote

whenever its front panel LCL key

is

pressed.

3-16. Addressing

The Distortion Analyzer interprets the byte on the

bus’ eight

data

lines as an address

or

a bus command

if the

bus

is

in

the command mode: attention control

line (ATN) true and interface clear control line (IFC)

false. Whenever the Distortion Analyzer is being ad-

dressed (whether in local

or

remote), the AD-

DRESSED annunciator on the front-panel will turn

on.

The Distortion Analyzer talk and listen addresses are

switch selectable as described under paragraph

2-7

in Section

2.

Refer to Table

2-1

for

a

comprehensive

listing of all valid HP-IB address codes.

To

determine

the present address setting, refer to the discussion

titled HP-IB Address in the Detailed Operating In-

structions near the end of this section.

3-19

Operation Model

89033

Table

3-3.

Message Reference Table

(1

of

2)

and

Controls

Interface

Functions'

ipplicable Response

Yes AH

1

SH

1

T5, TEO

L3, LEO

All

Distortion Analyzer operations except the LINE and

FLOAT switch functions are bus-programmable. All

measurement results, special displays, and error outputs

except the

'I-

- -

-"

display are available to the bus.

If

in remote and addressed to listen, the Distortion

Analyzer makes a settled measurement according to previ-

ously programmed setup. It responds equally to bus com-

mand GET and program code T3, Trigger with Settling (a

Data message).

Yes GET DT1

Yes Sets MEASUREMENT to AC LEVEL with the

80

kHz LP

FILTER on, and sets the trigger mode to free run. Resets

many additional parameters as shown in Table 3-5. Clears

Status Byte,

RQS

bit, Require Service message (if issued)

and Local Lockout. Sets the Service Request Condition to

the

22.2

state. Responds equally to Device Clear (DCL)

and Selected Device Clear (SDC) bus commands.

DCL

SDC DC1

Yes

~~~ ~~

Remote mode is enabled when the REN bus control line is

true. However, remote mode is not entered until the first

time the Distortion Analyzer is addressed to listen. The

front-panel REMOTE annunciator lights when the instrument

is actually in the remote mode. When entering remote

mode, no instrument settings or functions are changed, but

all front-panel keys except LCL are disabled, and entries in

progress are cleared.

REN RL1

Yes The Distortion Analyzer returns to local mode (front-panel

control). Responds equally to the GTL bus command and

the front-panel LCL key. When entering local mode, no in-

strument settings or functions are changed but entries in

progress are cleared. In local, triggering is free run only.

GTL RL1

Yes Disables all front-panel keys including LCL. Only the con-

troller can return the Distortion Analyzer to local (front-

panel control).

LLO RL1

Yes REN RL1

Clear

Lockout/

Set Local

The Distortion Analyzer returns to local (front-panel control)

and local lockout is cleared when the REN bus control line

goes false. When entering local mode, no instrument set-

tings or functions are changed, but entries in progress are

cleared. In local, triggering is free run only.

The Distortion Analyzer has no control capability.

No

co

Pass Control/

Take Control

Yes The Distortion Analyzer sets the

SRQ

bus control line true

if an invalid program code is received. The Distortion

Analyzer will also set

SRQ

true, if enabled by the operator

to do

so,

when measurement data is ready or when an in-

strument error occurs.

SRQ

SR1

Require

Service

*Commands, Control lines, and Interface Functions are defined in

IEEE

Std.

488.

Knowledge

of

these

might not

be

necessary

if

your controller's manual describes programming in terms of

the

twelve

HP-IB Messages shown in

the

left

column.

3-20

Model

89033

Table

3-3.

Message Reference Table

(2

of

2)

Response

Status Byte

Yes

c-c

Status

Bit

I

Abort

I

Yes

The Distortion Analyzer responds to a Serial

Poll

Enable

(SPE)

bus

command

by

sending an 8-bit byte

when

ad-

dressed to talk.

If

the instrument

is

holding the

SRQ

con-

trol

line

true

(issuing

the Require Service message) bit

7

(RQS

bit)

in

the Status Byte and

the

bit

representing the

condition causing the Require Service message to be

is-

sued

will

both

be

true. The

bits

in

the

Status

Byte

are

latched

but

can be cleared

by:

1)

removing the causing condition, and

2)

reading the Status Byte.

~~~ ~

The Distortion Analyzer does not respond

to

a parallel poll.

The Distortion Analyzer stops talking and listening.

t

I I

and

Controls

SPE

SPD

~~

I

FC

Operation

Interface

Functions*

T5,

TEO

PPO

T5,

TEO

L3,

LEO

'Commands, Control lines, and Interface Functions are defined in IEEE Std.

488.

Knowledge of these might not be

necessary if your controller's manual describes programming in terms of the twelve

HP-IB

Messages shown in the left

column.

Complete

HP-IB

capability

as

defined

in

IEEE

Std.

488

and ANSI

Std.

MC1.1

is:

SH1,

AH1, T5,

TEO,

L3, LEO,

SR1,

RL1,

PPO,

DC1, DT1,

CO,

El.

Local Lockout.

When a data transmission is inter-

rupted, which can happen by returning the Distortion

Analyzer to local mode by pressing the LCL key, the

data could be lost. This would leave the Distortion

Analyzer in an unknown state. To prevent this, a

local lockout is recommended. Local lockout disables

the LCL key (and the Clear Key Function,

S

(Shift)

AVG/RMS) and allows return-to-local only under

program control.

NOTE

Return-to-local can also be accomplished

by

turning the Distortion Analyzer's

LINE

switch to

OFF,

then back to

ON.

However,

this technique has several disadvantages:

It defeats the purpose and advantages of

local lockout (that

is,

the system control-

ler will lose control of a system

element).

There are several

HP-IB

conditions that

reset to default states at turn-on.

3-17.

Data Messages

The Distortion Analyzer communicates on the inter-

face

bus

primarily with data messages. Data messages

consist of one

or

more bytes sent over the

8

data

bus lines, when the bus

is

in the data mode (attention

control line [ATN] false). Unless

it

is

set

to

Talk

Only, the Distortion Analyzer receives data messages

when addressed

to

listen. Unless

it

is

set to Listen

Only, the Distortion Analyzer sends data messages

or

the Status Byte message (if enabled) when ad-

dressed

to

talk. Virtually all instrument operations

available in local mode may be performed in remote

mode via

data

messages. The only exceptions are

changing the LINE switch and the FLOAT switch.

In addition, the Distortion Analyzer may be triggered

via data messages

to

make measurements at a particu-

lar time.

3-18.

Receiving the

Data

Message

Depending on how the internal address switches are

set, the Distortion Analyzer can either talk only, talk

status only, listen only,

or

talk and listen both (normal

operation). The instrument responds to Data mes-

sages when

it

is enabled to remote (REN control line

true) and

it

is addressed to listen

or

set to Listen

Only.

If

not set to Listen Only, the instrument re-

mains addressed to listen until

it

receives an Abort

message

or

until

its

talk address

or

a universal unlisten

command is sent by the controller.

Listen Only.

If

the internal LON (Listen Only) switch

is set to

"l",

the Distortion Analyzer is placed in the

3-21

Operation

Listen Only mode when the remote enable bus control

line (REN) is set true. The instrument then responds

to all Data messages, and the Trigger, Clear, and

Local Lockout messages. However,

it

is inhibited from

responding to the Local

or

Abort messages and from

responding to a serial poll with the Status Byte

message.

Listen Only mode is provided to allow the Distortion

Analyzer to accept programming from devices other

than controllers (for example, card readers).

Data

Input

Format.

The Data message string,

or

program string, consists of a series of ASCII codes.

Each code is typically equivalent to a front-panel

keystroke in local mode. Thus, for a given operation,

the program string syntax in remote mode

is

the

same as the keystroke sequence in local mode.

Example

1

shows the general case programming order

for selecting Distortion Analyzer functions. Specific

program order considerations are discussed in

following paragraphs under “Program Order Consider-

ations”. All functions can be programmed together

as

a continuous string as typified in Example

2.

The

string in Example

2

clears most Special Functions

(with Automatic Operation), selects a distortion

measurement with 30 kHz low-pass filtering and log

units, then triggers a settled measurement.

Program

Codes.

All

of

the valid HP-IB codes

for

controlling Distortion Analyzer functions are summa-

rized in Table 3-6. All front-panel keys except the

LCL key have corresponding program codes.

Table 3-4 shows the Distortion Analyzer’s response

to various ASCII characters not used in

its

code set.

The characters in the upper table will be ignored

Model 89033

unless they appear between two characters of a

program code. The characters in the lower table,

if

received by the Distortion Analyzer, will always cause

Error

24

(invalid HP-IB code)

to

be displayed and

a Require Service message to be generated. The con-

troller recognizes the invalid code entry and clears

the Require Service condition. Thereafter, the invalid

code entry is ignored, and subsequent valid entries

are processed in normal fashion. As a convenience,

all lower case alpha characters are treated as upper

case.

In addition to the ignored codes given in Table 3-4,

codes used in the HP 8903A and 8903B Audio Analyz-

ers but not common to the Distortion Analyzer are

ignored. (They do not generate an error message.)

For

example, the output code

”APlVL”,

which sets

the audio analyzer’s source

to

lV,

will be ignored.

Table

3-4.

Distortion Analyzer Response

to

Unused

ASCII

Codes

I

lgnoredt

I

Generate Error

24

1

A

@

I

Z

B

J

[.

G

Y

1

I

-

E

Q

\

DEL

tExcept when inserted between two characters

of

a

program code.

EXAMPLE

1:

General Program Syntax and Protocol*

1

Controller Talk

Audio Analyzer Listen

[Automatic Operation] [Measurement] [Filters] [Special Functions] [Log/Lin] [Ratio] [Trigger]

{

‘Excluding Rapid Frequency

Count

Mode

EXAMPLE

2:

Typical Program String

AUMSLl

LGT3

-Trigger With Settling

Controller Talk

Audio Analyzer Listen

Automatic Operation

2

Distortion

rTL_

Log

30

kHz Low-Pass Filter

3-22

Model 89033 Operation

Turning

off

Functions.

When operating in local mode

the High-Pass/Bandpass (optional plug-in filters) and

Low-Pass Filters and the Notch Tune, the AVG/

RMS, and Ratio functions toggle

on

and off with

successive keystrokes. In remote mode, these func-

tions do not toggle on and off. Instead, each of the

above groups has a specific code which turns off all

the keys in the group. The HP-IB codes for turning

off these functions are given in the table below.

I

Function

I

HP-IB

Code

I

Average

off

(returns

to

RMS

mode)

HP/BP

FILTERS

all

off

LP

FILTERS all

off

NOTCH

HOLD

off

RATIO

off

Programming Numeric Data.

When entering ratio

references to the Distortion Analyzer, certain precau-

tions should be observed. Numeric data may be

entered in fixed, floating point,

or

exponential for-

mats. Usually, numeric data consists of

a

signed man-

tissa of up to five digits (including leading zeros),

one decimal point, and one-

or

two-digit signed expo-

nent. The decimal point may fall between any two

digits of the mantissa but should not appear ahead

of the fiist digit.

If

it

does, a leading zero will be

automatically inserted by the Distortion Analyzer.

Any digit beyond the five allowed for the mantissa

will be received as zero. The general format for nu-

meric data entry

is

given below, followed by several

examples illustrating various entries and the resulting

data as received by the Distortion Analyzer.

General Numeric Data Input Format:

+DDDDDE+NN

TTTT

LExponent Magnitude

IIL

Exponent Sign

Indicates Exponent

Follows

Example:

+

.12345E+01 issued

Example: 0.123403+01 received by

Example: +1234563+01 issued

Example: +12345OE+Ol received by

Example: +00012345 issued

Example: 12000 received by

In general,

do

not issue numeric

data

with more

significant digits than can be displayed on the

Distortion Analyzer’s five-digit left display.

5-Digit SignedA

Mantissa

Distortion Analyzer

Triggering Measurements with the Data Message.

A

feature that

is

only available via remote program-

ming is the selection of free run, standby,

or

triggered

operation of the Distortion Analyzer. During local

operation the Distortion Analyzer

is

allowed

to

free

run, outputting data to the display as each

measurement

is

completed. In remote, three addi-

tional operating modes are allowed: Hold, Trigger

Immediate, and Trigger with Settling. In addition,

the Clear Key Function can act as a manual trigger

while the instrument is in remote. The trigger modes

and use of the Clear Key Function are described

below.

Free

Run

(TO).

This mode

is

identical to local

operation and

is

the mode of operation in effect when

no other trigger mode has been selected. The

measurement result data available to the bus are

constantly being updated as rapidly as the Distortion

Analyzer can make measurements.

A

Device Clear

message

or

entry into remote from local sets the

Distortion Analyzer to the Free Run mode.

Hold

(Tl).

This mode

is

used to set up triggered

measurements (initiated by program codes T2

or

T3,

the Trigger message,

or

the Clear Key Function ex-

plained below). In Hold mode, internal settings can

be altered by the instrument itself

or

by the user via

the bus. Thus, the signal at the MONITOR output

can change. However, the instrument

is

inhibited

from outputting any data

to

the front-panel key lights

and display,

or

to

the HP-IB except as follows. The

instrument will issue the Require Service message

or

if an HP-IB code error occurs. The instrument will

issue the Status

Byte

message

if

serial polled.

(A

serial poll, however, will trigger

a

new measurement,

update displays, and return the instrument to Hold.)

Upon leaving Hold, the front-panel indications are

updated

as

the new measurement cycle begins. The

Status

Byte

will

be affected (and the Require Service

message issued) by the events that occur during the

new measurement cycle. The Distortion Analyzer

leaves Hold when

it

receives either the Free Run,

Trigger Immediate, Trigger with Settling codes,

or

the Trigger Message, when the

S

(Shift) AVG/RMS

keys (the Clear Key Function) are pressed (if not in

Local Lockout),

or

when

it

returns to local

operation.

Trigger Immediate (T2).

When the Distortion

Analyzer receives the Trigger Immediate code,

it

akes one measurement in the shortest possible time.

!

he instrument then waits for the measurement

results to be read. While waiting, the instrument can

3-23

Operation Model 89033

process most bus commands without losing the

measurement results. However,

if

the instrument re-

ceives GTL (Go To Local), GET (Group Execute

Trigger),

or

its

listen address

or

if

it

is

triggered by

the Clear Key Function, a new measurement cycle

will be executed. Once the data (measurement results)

are read onto the bus, the Distortion Analyzer reverts

to the Hold mode. Measurement results obtained via

Trigger Immediate are normally valid only when the

instrument

is

in a steady, settled state.

Trigger with Settling

(T3).

Trigger with Settling

is

identical to Trigger Immediate except the

Distortion Analyzer inserts a settling-time delay

before taking the requested measurement. This set-

tling time

is

sufficient to produce valid, accurate

measurement results. Trigger with Settling

is

the trig-

ger type executed when a Trigger message is received

via the bus.

Triggering Measurements with the Clear Key

Function.

When the Distortion Analyzer

is

in remote

Hold and not in Local Lockout, the front-panel Clear

Key Function may be used to issue a Trigger with

Settling instruction. First place the instrument in

Hold mode (code

Tl).

Trigger the measurement by

pressing the

S

(Shift) and AVG/RMS keys. Each

time this key sequence is entered the Distortion

Analyzer performs one Trigger with Settling

Measurement cycle, then waits for the data to be

read. Once the data is read out

to

the bus, the instru-

ment returns to Hold mode.

If

data

is

not read

between trigger cycles,

it

will be replaced with data

acquired from subsequent measurements.

Special Considerations

for

Triggered Operation.

When in free-run mode, the Distortion Analyzer must

pay attention

to

all universal bus commands, for

example, serial poll enable (SPE), local lockout (LLO),

etc. In addition,

if

it

is addressed to listen,

it

must

pay attention

to

all addressed bus commands, for

example,

Go

To Local (GTL), Group Execute Trigger

(GET), etc. As a consequence of this, the Distortion

Analyzer must interrupt the current measurement

cycle

to

determine whether any action in response

to these commands

is

necessary. Since many elements

of the measurements are transitory, the measurement

must be re-initiated following each interruption.

Thus, if much bus activity occurs while the Distortion

Analyzer is trying to take a measurement, that

measurement may never be completed.

Trigger Immediate and Trigger with Settling provide

a way to avoid this problem. When the Trigger Imme-

diate

(T2)

and Trigger with Settling

(T3)

codes are

received, the Distortion Analyzer will not allow its

measurement to be interrupted. (Indeed, handshake

of bus commands is inhibited until the measurement

is

complete.) Once the measurement

is

complete, bus

commands will be processed, as discussed under Trig-

ger Immediate above, with no loss of

data.

Thus, in

an HP-IB environment where many bus commands

are present, Trigger Immediate

or

Trigger with Set-

tling should be used for failsafe operation.

Reading Data from the Right or

Left

Display.

The

Distortion Analyzer can only read

data

to the HP-IB

once for each measurement made. Only the informa-

tion on one display can be read each time. Use the

codes RR (read right display)

or

RL (read left display)

to control which information is read. The display

will remain selected until the opposing display

is

specified

(or

until a clear message

is

received

or

power-

up occurs). Errors (which occupy two displays) are

output as described above, and DC LEVEL

measurement results (always occupying the right

display only) are placed on the bus (when requested)

regardless of which display is enabled.

Program Order Considerations.

Although program

string

syntax

is

virtually identical to keystroke order,

some program order considerations need

highlighting.

Automatic Operation (AU).

When Automatic Op-

eration

is

executed in remote only,

it

sets all Special

Functions prefixed

1

through 8 to their zero-suffix

mode and also affects many other Special Functions.

Thus when Automatic Operation is used,

it

should

appear at the beginning of a program string.

Trigger Immediate and Trigger with Settling

(T2

and

T3).

When either of the trigger codes

T2

or

T3

is

received by the Distortion Analyzer, a

measurement is immediately initiated. Once the

measurement is complete, some

bus

commands can

be processed without losing the measurement results.

However, any HP-IB program code sent to the

Distortion Analyzer before the triggered measurement

results have been output will initiate a new

measurement Thus, trigger codes should always ap-

pear at the end of a program string, and the triggered

measurement results must be read before

any

addi-

tional program codes are sent.

3-19.

Sending the Data Message

Depending on how the internal address switches are

set, the Distortion Analyzer can either talk only, talk

status only, listen only,

or

talk and listen both (normal

operation).

If

set to both talk and listen, the instru-

ment sends Data messages when addressed to talk.

The instrument then remains configured to talk until

it

is

unaddressed to talk by the controller. To

unaddress the Distortion Analyzer, the controller

must send either an Abort message, a new talk ad-

dress,

or

a universal untalk command.

3-24

Model

89033

Talk

Only

Mode.

If

the internal address switches are

set to a valid Talk address and the TON (Talk Only)

switch

is

set to

“l”,

the Distortion Analyzer

is

placed

in the Talk Only mode. In this mode instrument

is

configured to send Data messages whenever the bus

is in the data mode. Each time the measurement

is

completed, the measurement result will be output to

the bus unless the listening device is not ready for

data. If the listener

is

not ready and the Distortion

Analyzer

is

not in a trigger mode, another

measurement cycle is executed.

Talk Status

Only

Mode.

If

all the internal address

switches and the TON (Talk Only) switch are set to

“l”,

but the LON (Listen Only) switch is set to

“0”,

the Distortion Analyzer is placed in the Talk Status

Only mode. In this mode the instrument

is

configured

to send a one-byte data message whenever the bus

is in the data mode. The byte sent is an exact copy

of

the Status Byte. Each time this byte

is

successfully

sent on the bus, the internal Status Byte is cleared.

The Data Valid (DAV) handshake line is pulsed each

time the one-byte Data message is sent.

Data Output Format.

As

shown below, the output

data

is

usually formatted as a real constant in expo-

nential form: first the sign, then five digits (leading

zeros not suppressed) followed by the letter

E

and a

signed power-of-ten multiplier. (Refer to

Rapid

Frequency Count

in the

Detailed Operation Instruc-

tions

for the only exception to this format.) The

string is terminated by a carriage return (CR) and a

line feed (LF), string positions

11

and 12. Data is

always output in hndamental units (for example, Hz,

volts,

dB,

%,

etc.), and the decimal point (not sent)

is assumed to be to the right of the fifth digit of the

mantissa. Data values never exceed

4

000

000.

Table

3-5.

Response to a Clear Message

Parameter

Operation

Data Output Format:

+DDDDDE+NNCRLF

Signed Man

tr

][-rLL

Line Feed

NOTE

For the only exception to the above format,

refer to Rapid Frequency Count in the

Detailed Operating Instructions.

When an error is output to the bus,

it

follows the

same twelve-byte format described above except most

of the numeric digits have predetermined values as

shown below.

Error

outputs always exceed

9

000

000.

The two-digit error code

is

represented

by the last two digits of the five-digit mantissa. The

error code can be derived from the string by subtract-

ing

9

X

lo9, then dividing the results by 100000.

Error Output Format:

I

nd

i

cates Exponent

Fo

I

lows

Carriage Return

Exponent Sign Exponent Magnitude

+900DDE+05C

R

L

F

3

PLine Feed

Error Code Carriage Return

3-20.

Receiving the Clear Message

The Distortion Analyzer responds

to

the Clear message

by assuming the settings detailed in Table

3-5.

The

Distortion Analyzer responds equally

to

the Selected

Device Clear (SDC) bus command when addressed to

listen, and the Device Clear (DCL) bus command

whether addressed

or

not. The Clear message clears

any pending Require Service message and resets the

Service Request Condition (Special Function

22)

such

that the Require Service message will be issued on

HP-IB

code errors only (Special Function

22.2).

Measurement

Detection

Low-Pass

(LP)

Filter

High-Pass (HP)/ Bandpass

(BP)

(optional

plug-in Filters)

Special Functions

Ratio

Log/Lin

Right Display Read

Service Request Condition

Status Byte

Trigger

Mode

Local Lockout

Settina

AC

Level

RMS

80

kHz Low-Pass

On

All

off

All

Special Functions off or set to

their

zero-suffix mode

except Service Request Condition set to

22.2

(HP-I8

code error).

Off

Linear

(Refer

to

RATIO

and LOG/LIN Detailed Operating

Enabled

HP-IB Code Error

Only

Cleared

Free

Run

(Code

TO)

Cleared

Instructions.)

3-25

Operation

3-21. Receiving the Trigger Message

When in remote and addressed to listen, the

Distortion Analyzer responds to a Trigger message

by executing one settled-measurement cycle. The

Distortion Analyzer responds equally to a Trigger

message (the Group Execute Trigger bus command

[GET]) and a Data message, program code T3 (Trigger

with Settling). Refer

to

“Triggering Measurements

with the Data Message” under paragraph 3-18,

Receiu-

ing

the Data Message.

Model 89033

3-22. Receiving the Remote Message

The Remote message has two parts. First, the remote

enable bus control line (REN)

is

held true, then the

device listen address

is

sent by the controller. These

two actions combine to place the Distortion Analyzer

in remote mode. Thus, the Distortion Analyzer

is

enabled to go into remote when the controller begins

the Remote message, but it does not actually switch

to remote until addressed to listen the first time. No

instrument settings are changed by the transition

from local to remote, but the Trigger mode is set to

Free Run (code

TO).

When actually in remote, the

Distortion Analyzer lights

its

front-panel REMOTE

annunciator. When the Distortion Analyzer

is

being

addressed (whether in remote

or

local),

its

front-panel

ADDRESSED annunciator turns on.

3-23. Receiving the Local Message

The Local message

is

the means by which the control-

ler sends the

Go

To Local (GTL) bus command. If

addressed to listen, the Distortion Analyzer returns

to front-panel control when it receives the Local

message.

If

the instrument

was

in local lockout when

the Local message was received, front-panel control

is returned, but lockout is not cleared. Unless

it

re-

ceives the Clear Lockout/Set Local message, the

Distortion Analyzer will return to local lockout the

next time

it

goes to remote.

No

instrument settings

are changed by the transition from remote to local,

but all measurements are made in a free run mode.

When the Distortion Analyzer goes to local mode,

the front-panel REMOTE annunciator turns off.

However, when the Distortion Analyzer

is

being ad-

dressed (whether in remote

or

local),

its

front-panel

ADDRESSED annunciator lights.

If

the Distortion Analyzer is not in local lockout

mode, pressing the front-panel LCL (local) key might

interrupt a Data message being sent to the instrument,

leaving the instrument in a state unknown to the

controller. This can be prevented by disabling the

Distortion Analyzer’s front-panel keys entirely using

the Local Lockout message.

3-24. Receiving the Local Lockout Message

The Local Lockout message

is

the means by which

the controller sends the Local Lockout (LLO) bus

command.

If

in remote, the Distortion Analyzer re-

sponds to the Local Lockout Message by disabling

the front-panel LCL (local) key and the Clear Key

Function. (In remote, the Clear Key Function initiates

a Trigger with Settling cycle.) The local lockout mode

prevents

loss

of data

or

system control due to someone

accidentally pressing front-panel keys. If, while in

local, the Distortion Analyzer

is

enabled to remote

(that

is,

REN

is

set true) and

it

receives the Local

Lockout message,

it

will switch to remote mode with

local lockout the first time

it

is

addressed to listen.

When in local lockout, the Distortion Analyzer can

be returned

to

local only by the controller (using the

Local

or

Clear Lockout/Set Local messages),

or

by

setting the LINE switch

to

OFF

and back to ON,

or

by removing the bus cable.

3-25. Receiving the Clear LockoutlSet Local

Mess

age

The Clear Lockout/Set Local message

is

the means

by which the controller sets the Remote Enable

(REN) bus control line false. The Distortion Analyzer

returns to local mode (full front-panel control) when

it

receives the Clear Lockout/Set Local message.

No

instrument settings are changed by the transition

from remote with local lockout to local. When the

Distortion Analyzer goes to local mode, the front-

panel REMOTE annunciator turns off.

3-26. Receiving the Pass Control Message

The Distortion Analyzer does not respond to the

Pass

Control message because

it

cannot act as a

controller.

3-27. Sending the Require Service Message

The Distortion Analyzer sends the Require Service

message by setting the Service Request (SRQ) bus

control line true.

The

instrument can send the Require

Service message in either local

or

remote mode. The

Require Service message

is

cleared when a serial poll

is

executed by the controller

or

if

a Clear message

is

received by the Distortion Analyzer. (During serial

poll, the Require Service message

is

cleared immedi-

ately before the Distortion Analyzer places the Status

Byte message on the bus.) An HP-IB code error will

always cause a Require Service message to be issued.

In addition, there are two other conditions which

can be enabled to cause the Require Service message

to be sent when they occur. All three conditions are

described as follows.

3-26

Model 89033 Operation

a

Data Ready: When the Distortion Analyzer

is

ready

to send any information except error codes

or

the

Status Byte.

HP-IB Code Error: When the Distortion Analyzer

receives an invalid Data message. (This condition

always causes a Require Service message to be sent.)

NOTE

The

“----”

display indicates a transient

condition. After nine attempts to make a

measurement, it is replaced by

Error

31

which causes the Require Service message

to be sent.

Instrument Error: When any

Error

is

being

displayed by the Distortion Analyzer including

HP-

IB Code error, Error

24.

3-28. Selecting the Service Request

Condition

Use Special Function

22,

Service Request Condition,

to enable the Distortion Analyzer to issue the Require

Service message on any of the conditions above (ex-

cept HP-IB code errors which always cause the Re-

quire Service message to be sent). The Service

Request Condition Special Function is entered from

HP-IB. The conditions enabled by Special Function

22

are always disabled by the Clear message. A

description of the Service Request Condition Special

Function and the procedure for enabling the various

conditions are given under

Service Request Condition

in the

Detailed Operation Instructions.

Normally,

device subroutines for the Distortion Analyzer can

be implemented simply by triggering measurements

then reading the output

data.

In certain applications,

the controller must perform other tasks while control-

ling the Distortion Analyzer. Figure

3-7

illustrates a

flow chart for developing device subroutines using

the instrument’s ability to issue the Require Service

message when data is ready. This sub-routine struc-

ture frees the controller to process other routines

until the Distortion Analyzer is ready with data.

3-29. Sending the Status Byte Message

The Status Byte message consists of one %bit byte

in which

3

of the bits are set according to the enabled

conditions described above under Sending

the

Require

Service Message. If one

or

more of the three condi-

tions described above are both enabled and present,

all the bits corresponding to the conditions and also

bit

7,

the

RQS

bit, will be set true (and the Require

Service message

is

sent). If one of the above condi-

tions occurs but has not been enabled by Special

Function

22,

neither the bit corresponding to the

condition nor the

RQS

bit will be set (and the Require

Service message will not be sent). The bit pattern

of

the Status Byte is shown in the table labeled “Status

Byte:”, on the following pages.

Once the Distortion Analyzer receives the serial poll

enable bus command (SPE),

it

is

no longer allowed

to

alter the Status Byte. When addressed to talk

(following SPE), the Distortion Analyzer sends the

Status Byte message.

NOTE

Since the Distortion Analyzer cannot alter

the Status Byte while

in

serial

poll

mode,

it

is

not possible to continually request the

Status Byte while waiting

for

a condition

to cause a bit

to

be set.

After

the Status

Byte

message has been sent

it

will

be cleared if the Serial Poll Disable (SPD) bus com-

mand

is

received, if the Abort message

is

received,

or

if the Distortion Analyzer is unaddressed to talk.

Regardless of whether

or

not the Status Byte message

has been sent, the Status Byte and any Require

Service message pending will be cleared if

a

Clear

message

is

received. If the instrument

is

set

to

Talk

Only, the Status Byte is cleared each time the one-

byte Data message

is

issued to the bus.

3-30. Sending the Status Bit

Message

The Distortion Analyzer does not respond to a Paral-

lel Poll Enable (PPE) bus command, and thus cannot

send the Status Bit Message.

3-31. Receiving the

Abort

Message

The Abort Message

is

the means by which the control-

ler sets the Interface Clear (IFC) bus control line

true. When the Abort message

is

received, the

Distortion Analyzer becomes unaddressed and

stops

talking

or

listening.

3-27

0

per

at

i

o

n

Model

89033

(

START 8903E

)

I

SET TRIGGER

MODE TO HOLD

(HP-18 CODE T1)

I

ENABLE

SRQ

ON

I

DATA READY

I

(HPIIB

CODE 22.3SP)

I

c

CONF

1

GURE

MEASUREMENT

I

TRIGGER MEASUREMENT

(HP-IB CODE T2

I

OR

T3).

1

PROCESS OTHER

ROUTINES UNTIL

SRQ

CAUSES INTERRUPT

TO OTHER INSTRUMENT

SERVICE ROUTINES

INTERRUPT

ON

SRO

T

READ STATUS BYTE

FROM 8903E

SRQ

FROM

8903E

I

1

I

TEST OTHER 8903E

le

NO <9::tntp DUE TO DATA

SRQ

CONDITIONS

YES

READ DATA

I

FROM

8903E

I

4

(-)

Figure

3-4.

Example

Flow

Chart

for

Driving the Distortion Analyzer Using the Require Service Message (SRQ)

3-28

Model 89033

HP-IB

SYNTAX AND CHARACTERISTICS SUMMARY

Bit

8

7

6

5

4

3

2

Weight

128 64

32

16 8

4

2

HP4B

Service

RQS

Bit

Instru-

Request

0

(always)

Require

0

(always)

0

(always)

0

(always)

ment Code

Condition

Service Error Error

Operation

1

Data

Ready

Address:

Set in binary by internal switches

-

may be displayed on front panel using

S

(Shift) LCL. Factory

set

to

28

decimal.

General Operating Syntax:

(Excluding Rapid Frequency Count modes.)*

[Automatic Operation]

[Measurement]

[Filters] [Special Functions]

[Log/Lin]

[Ratio]

Numeric Data Input Format:

(Except in Rapid Source mode.)*

f

DDDDDEkNN

Exponent Magnitude

Exponent Sign

5-Digit Signed Mantissa

(leading decimal not allowed)

Indicates Exponent Follows

Output

Formats:

(Except in Rapid Frequency Count mode.)*

Data (valid data output value always

<4

X

109

and

in fundamental units):

+DDDDDE+NNCRLF

Signed Mantissar

TIT

T

Line Feed

Exponent Sign Exponent Magnitude

Indicates Exponent Follows Carriage Return

~~~~ ~

*

For information on Rapid Frequency

Count

mode refer

to

it

by name in the Detailed Operating

Instructions.

3-29

Operation

Table

3-6.

Distortion Analyzer Parameter to HP-IB Code Summary

Parameter

Automatic Operation

SPCL

SPCL SPCL

Measurements

AC Level

SINAD

Distortion

DC Level

Distortion Level

RMS Detector

AVG Detector

Automatic Notch Tuning

Notch Hold

Internal Plug-in HP/BP Filters

Left Plug-in Filter on

Right Plug-in Filter on

All

Plug-in HP/BP Filters

off

30

kHz LP Filter on

80

kHz LP Filter on

All LP Filters

off

LP Filters

Program Code

AU

SP

ss

M1

M2

M3

s1

s3

A0

A1

NO

N1

H1

H2

HO

L1

L2

LO

Parameter

Ratio

On

Off

Log/Lin

Lin

Log

Trigger Modes

Free Run

Hold

Trigger Immediate

Trigger with Settling

Miscellaneous

Read Left Display

Read Right Display

Rapid Frequency Count

Clear Key Function*

'Not

to

be confused with Clear message which

is

defined

in

Table

3.

Program Code

R1

RO

LG

LN

TO

T1

T2

T3

RL

RR

RF

CL

Model

89033

Program Code

A0

A1

AU

CL

HO

H1

H2

LG

LN

LO

L1

L2

M1

M2

M3

NO

N1

Table

3-7.

Audio

Analyzer HP-IB Code

to

Parameter Summary

Parameter

11

Program

COG

RMS Detector

AVG Detector

Automatic Operation

Clear Key Function*

All

Internal Plug-in HP/BP Filters

off

Left Plug-in Filter on

Right Plug-in Filter on

Log

Linear

All LP Filters

off

30

kHz LP Filter

on

80 kHz LP Filter on

AC Level

SINAD

Distortion

Automatic Notch Tuning

Notch Hold

RF

RL

RR

RO

R1

SP

ss

s1

s3

TO

T1

T2

T3

-

0-9

*Not

to

be confused with Clear messaae which

is

defined in Table

3-3.

Parameter

Rapid Frequency Count

Read Left Display

Read Right Display

Ratio on

Ratio

off

SPCL

SPCL SPCL

DC Level

Distortion Level

Free Run

Hold

Trigger Immediate

Trigger with Settling

-

(minus)

0-9

.

(decimal point)

3-30

Model

89033

Operation

Table

3-8.

Distortion Analyzer Special Function

to

HP-IB

Code

Summary

Special Function

Input Level Range (except DC Level)

Automatic Selection

300V range

189V range

11 9V range

75.4V range

47.6V range

30.0V range

18.9V range

11.9V range

7.54V range

4.76V range

3.00V range

1.89V range

1.19V range

0.754V range

0.476V range

0.300V range

0.189V range

0.1 19VV range

0.0754V range

Automatic Selection

300V range

64V range

16V range

4V range

Post Notch Gain

Automatic Selection

0

dB gain

20 dB gain

40 dB gain

60 dB gain

Hold Decimal Point

Automatic Selection

DDDD. range

DDD.D range

DD.DD range

D.DDD range

O.DDDD range

DD.DD

rnV

range

D.DDD mV range

0.DDDD rnV range

Input Level Range (DC Level only)

Post Notch Detector Response

(except in SINAD)

Fast RMS Detector

Slow

RMS

Detector

Fast AVG Detector

Slow AVG Detector

Automatic notch tuning

Hold notch tuning

Notch Tune

Program Code

1 .OSP

1.lSP

1.2SP

1.3SP

1.4SP

1.5SP

1.6SP

1.7SP

1.8SP

1.9SP

1.1OSP

1.1lSP

1.12SP

1.13SP

1.14SP

1.15SP

1.1 6SP

1.17SP

1.18SP

1.1 9SP

2.0SP

2.1 SP

2.2SP

2.3SP

2.4SP

3.0SP

3.1 SP

3.2SP

3.3SP

3.4SP

4.0SP

4.1 SP

4.2SP

4.3SP

4.4SP

4.5SP

4.6SP

4.7SP

4.8SP

5.0SP

5.1

SP

5.2SP

5.3SP

6.0SP

6.1SP

~~ ~ ~ ~~

Special Function

Error Disable

All

errors enabled

Disabled Analyzer errors

(Errors 12-17,31, and 96)

Disable External Source errors

(Error 19)

Hold Settings

Hold input level ranges,

post-notch gain, decimal

point and notch tuning

at present settings.

Re-enter Ratio Mode

Restore last RATIO reference

Display RATIO reference.

Time Between Measurements

Minimum time between

Add 1

s

between measurements

and enter RATIO mode if allowed.

measurements

SINAD Display Resolution

0.5 dB below 25 dB

0.01

dB above 25 dB;

0.01

dB

all ranges

Display Level in Watts

Display level as watts into 852.

Display level as watts into NNNR.

Read Display

to

HP-IB.

Read right display.

Read left display.

Displays HP-IB address (in binary)

in left display; right display

in form

TLS

where T=l

means talk only;

L=l

means

listen only; S=l means

SRQ.

HP-IB Address

Displays HP-IB address

in

decimal.

HP-I6 Service Request Condition

Enable a Condition to cause a

service request, N is the sum

of

any combination of the

weighted conditions below:

1-Data Ready

2-HP-IB error

4-Instrument error

The instrument powers

up

in

the 22.2 state (HP-IB error).

Program

Code

~~

8.0SP

8.1 SPor

8.3SP

8.2SP'

*(This code is

ignored)

9.OSP

11 .OSP

11.1SP

14.0SP

14.1SP

16.0SP

16.1 SP

19.OSP

19.NNNSP

20.0SP

20.1SP

21 .OSP

21.1 SP

22.NSP

3-31

Operation

Model

89033

Table

3-9.

Commonly- Used Code Conversions

ASCII

NUL

SOH

STX

ETX

EOT

EN0

ACK

BEL

BS

HT

LF

VT

FF

CR

so

SI

DLE

DC1

DC2

DC3

DC4

NAK

SY

N

ETB

CAN

EM

SUB

ESC

FS

GS

RS

us

SP

-

I

#

$

010

8

(

)

-

/

0

1

2

3

4

5

6

7

8

9

7

Binary

00

000

00

000

001

00

000

01

0

00 000

01 1

00

000

100

00 000

101

00

000

110

00

000

111

00

001

000

00

001 001

00

001 010

00001 011

00

001 100

00

001 101

00

001 110

00001 111

00

010

000

00

010 001

00

010 010

00

010 011

00

010 100

00

010 101

00

010 110

00

010 111

00011

OOO

00

011 001

00

011 010

00

011 011

00

011 100

00

011 101

00

011 110

00011 111

00

100

OOO

00

100 001

00

100 010

00100011

00

100

loo

00

100 101

00

100 110

00

100 111

00

101

000

00

101 001

00

101 010

00

101 011

00

101 100

00

101 101

00

101 110

00

101 111

00

110

000

00

110 001

00

110 010

00110011

00

110 100

00

110 101

00

110 110

00

110 111

00

111

000

00

111 001

00

111 010

00

111 011

00

111 100

00

111 101

00

111 110

00

111 111

-

Octal

000

00

1

002

003

004

005

006

007

010

01 1

012

013

014

015

016

017

020

021

022

023

024

025

026

027

030

031

032

033

034

035

036

037

040

041

042

043

044

045

046

047

050

051

052

053

054

055

056

057

060

061

062

063

064

065

066

067

070

071

072

073

074

075

076

077

-

Decima

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

-

Hexa-

decimal

00

01

02

03

04

05

06

07

08

09

OA

OB

oc

OD

OE

OF

10

11

12

13

14

15

16

17

18

19

1A

1B

1c

1D

1E

1F

20

21

22

23

24

25

26

27

28

29

2A

28

2c

2D

2E

2F

3G

31

32

33

34

35

36

37

38

39

3A

38

3c

3D

3E

3F

-

ASCII

0

A

B

C

D

E

F

G

H

I

J

K

L

M

N

0

P

R

S

T

U

v

W

X

Y

Z

I

a

\

I

A

-

a

b

C

d

e

f

9

h

I

k

I

m

n

I

0

P

q

r

S

t

U

v

W

X

Y

z

i

I

DEL

-

01

000

01

000

001

01

000

010

01

000

011

01

000

100

01

000

101

01

000

110

01

000

111

01 001

000

01 001 001

01 001 010

01 001 011

01 001 100

01 001 101

01 001 110

01 001 111

01 010

000

01 010 001

01 010 010

01 010 011

01 010 100

01 010 101

01 010 110

01 010 111

01 011

000

01 011 001

01 011 010

01 011 011

01 011 100

01 011 101

01 011 110

01 011 111

01 100

000

01 100 001

01 100010

01 100011

01 100 100

01 100 101

01 100 110

01 100 111

01 101

000

01 101 001

01 101

010

01 101 011

01 101 100

01 101 101

01 101 110

01 101 111

01 110

000

01 110 001

01 110010

01 110011

01 110 100

01 110 101

01 110 110

01 110 111

01 111

000

01 111 001

01 111 010

01 111 011

01 111 100

100

101

102

103

104

105

106

107

110

111

112

113

114

115

116

117

120

121

122

123

124

125

126

127

130

131

132

133

134

135

136

137

140

141

142

143

144

145

146

147

150

151

152

153

154

155

156

157

160

161

162

163

164

165

166

167

170

171

172

173

174

40

41

42

43

44

45

46

47

48

49

4A

48

4c

40

4E

4F

50

51

52

53

54

55

56

57

58

59

5A

58

5c

5D

5E

5F

60

61

62

63

64

65

66

67

68

69

6A

6B

6C

60

6E

6F

70

71

72

73

74

75

76

77

78

79

7A

78

7c

7D

7E

7F

3-32

Model

8903B

Description

Procedure

Example

Program Code

Indications

Measurement

Technique

Operation

AC

Level

The Distortion Analyzer contains a wideband, true rms

or

average-responding voltmeter

with high accuracy and sensitivity. Pressing the AC LEVEL key causes the Distortion

Analyzer to measure the differential ac voltage between the center and outer conductor of

the INPUT connector

or,

for Option 001 only, the center conductors of the (rear-panel)

INPUT connectors. Signals common to both high and low inputs are rejected. See the

following Warning and Caution.

To avoid the possibility

of

hazardous shock on standard instruments (those

without Option

OOl),

do

not apply more

than

42Vpeak to the outer conductor

of

the

BNC

INPUT connector when the FLOAT switch

is

in the FLOATposition.

~

3-33

Do

not apply

more

than

300

Vrms (either differential, common-mode,

or

a

combination) to the INPUT connector(s).

To make an ac level measurement, press the AC LEVEL key. AC level results can be

displayed in

V,

mV, Bm, watts,

or

as the ratio

to

an entered

or

measured value. The

Distortion Analyzer powers up displaying ac level

in

linear units (mV

or

V). To obtain

a

display in dBm (that is,

dI3

relative

to

1

milliwatt into a 600-ohm load, equivalent to dBre

0.775V), press the LOG/LIN key. To return to linear, simply press the LOG/LIN key again.

If

the ac level

is

to be displayed relative

to

a reference, refer

to

Ratio

and

LOG/LIN.-

To measure the ac level of a signal

at

the INPUT connector:

LOCAL

(keystrokes)

Measurement

7

AC

iY

(program

codes)

M1

T

Measurement

M1 is the program code

for

AC LEVEL.

When ac level

is

selected, the LED within the AC LEVEL key will light. The right display

shows the ac level with the appropriate units. The Distortion Analyzer automatically ranges

for maximum resolution and accuracy. The left display shows the input signal frequency.

If

the input level to the frequency counter is too small, the left display will show

0.000

kHz.

(This will often occur when the signal is in the stop band of the optional plug-in HP/BP

filters, but not the low-pass filters.)

In ac level the Distortion Analyzer acts as an ac voltmeter. The Distortion Analyzer

automatically sets the input attenuation and the gain settings of the various amplifiers

so

that the input signal amplitude lies within the range of the output detector. The output

Operation Model

8903B

AC

Level

(cont’d)

Measurement

Technique

(cont’d)

detector converts the ac level to a dc voltage which

is

then measured by the dc voltmeter

and after correction

for

input gain and attenuation, displayed in appropriate units. The

frequency of the input signal is also measured and displayed.

COUNTER/

LEFT DISPLAY

(FREQUENCY)

INTERNAL

PLUG-IN

VOLTMETER/

(AMPLITUDE)

HP/BP OUTPUT

FILTERS

RWAVG

LOW-PASS

DETECTOR

RIGHT DISPLAY

INPUT

-

.qC/,r/

-ucu

bU

-

INPUT PROGRAMABLE

PR~GRAHAELE

AMPLIFIER GAIN AMPLIFIER GAIN AMPLIFIER

AC

Level Measurement Block Diagram

Com men ts

The Distortion Analyzer powers up in the ac level measurement mode with the

80

kHz

low-pass filter activated. The

80

kHz

low-pass filter reduces the measurement bandwidth

from

750

kHz

to

80

kHz.

Two ac level detectors are available: true rms and average-responding (but

rms

calibrated).

See the section

Detector Selection

for

details.

Common Mode

Detector Selection

Display Level in Watts

Filters

Monitor

RATIO and

LOG/LIN

Special Functions

3-34

Model

89033

Operation

Automatic Operation

Description

The Automatic Operation code sets the instrument functions to automatic (that is, each

function is allowed to automatically range

to

the appropriate setting).

It

also cancels all of

the special functions.

Procedure

To set the Distortion Analyzer to automatic operation, you must use HP-IB.

Example

To set the Distortion Analyzer to automatic operation:

(program

codes)

AU

7-

Function

Program Code

AU is the HP-IB code for Automatic Operation.

indications

When the HP-IB program code is entered, the left and right displays

blank,

the right display

shows four dashes, then both displays show the current measurement mode and input.

Comments

The converse

of

the automatic operation mode

is

the Hold Settings Special (prefixed9).

Refer to

Hold

Settings.

For

information on which specific Special Functions are turned off by the Automatic

Operation mode, refer

to

Special Functions. Since Automatic Operation affects Special

Functions,

it

is

a good practice to place the AU code at the beginning of a program string

when programming the instrument.

Sections

Special Functions

3-35

Operation Model

89033

Common

Mode

Description

.

Common-mode rejection ratio,

or

“common-mode” as

it

is

usually referred

to,

is

a measure

of the ability of an amplifier to reject

signals

that are common

to

both amplifier inputs

while allowing the differential signals (which may

or

may not be the weaker signal)

to

be

amplified and passed on

to

the measurement circuitry.

Since the analyzer input is fully balanced,

it

can reject signals which are common to the

High and Low Inputs (with the INPUT FLOAT switch in the FLOAT position).

For

standard instruments, the High Input

is

the center conductor of the INPUT BNC connector;

the Low Input is its outer conductor. For instruments with Option

001,

the High and Low

Inputs are the center conductors of the respective HIGH and

LOW

INPUT connectors.

However, for valid measurement results, there are limitations

to

the maximum level of

common-mode signals.

To

avoid the possibility of hazardous shock on standard instruments (those without

Option

OOl),

do not apply more than 42V peak to the outer conductor of the

BNC INPUT connector when the FLOAT switch

is

in

the FLOAT position.

Do

not apply more than

300

Vrms (either differential, common-mode,

or

a

combination) to the INPUT connector(s).

Common-mode signal limitations exist because the instrument’s ranging detector (which

determines the input voltage range),

is

designed

to

read only the

differential

signal (between

the High and

Low

Inputs). Thus, the instrument can set an incorrect input range

if

a large

common-mode signal is present. Erroneous measurements may be obtained

as

a

result.

The Analyzer Input Block Diagram illustrates that the ranging detector senses the voltage

difference between the High and Low Input lines. Common-mode signals are “ignored”

by

the ranging detector, while the differential signals are measured. The block diagram also

illustrates that the High and Low Input lines have over-voltage protection circuits

that open

when the input voltage (single

or

combined common-mode and differential) exceeds the

maximum safe limit.

OVER-VOLTAGE

PROTECTION

DIFFERENTIAL-TO-

SINGLE-ENDEO CONVERTER

HIGH INPUT

ATTENUATOR

TO PROGRAMMABLE

GAIN AMPLIFIER

‘

HIGH

fl

LOW

INPUT

ATTENUATOR

Low

h

L

Analyzer Input Block Diagram

3-36

Model 89033 Operation

Common

Mode

(cont’d)

Example

If

a common-mode signal of 1OV is on the analyzer’s input with a 1V differential signal,

the ranging detector selects the 1.19V range. The signal that

is

present at the input

is

actually 11V

(1OV

common-mode signal

+

the 1V differential signal).

A

voltage signal this

large can exceed the input amplifiers’ operating range and cause erroneous measurements.

However, the instrument will not be damaged because the Over-voltage Protection circuitry

will open whenever the combined common-mode and differential signals exceed the

instrument’s safe operating range. (Setting Special Function

1.8

will set the input range to

11.9V.)

Comments

For

error-free measurements, the Operating Region

For

Valid

Measurements graphs, shown

below, indicate the maximum allowable common-mode input voltages for a given differential

input voltage. Case

1

is

for a single-ended source with a common-mode signal present on

both input lines. Case

2

is

for

a

balanced source with common-mode signals on both input

lines.

To

obtain the maximum common-mode input voltage level

from

the graphs, select the desired

value for the differential input voltage. Then read the common-mode input voltage level.

For example, on the Case

1

graph, for a differential input voltage level of lV, the maximum

common-mode input voltage level

is

2.8V.

For

a differential input voltage of 20V, the

maximum common-mode input level

is

20V.

Y

0

c

-8

c

a.

z

Y

a

-

8

7

3

0

3dOV

OIFFERENTIAL

INPUT

VOLTAGE

CASE

1.

Single-Ended Source

with

Common

Mode

on

Both

Lines

3-37

Operation

Comments

(cont’d)

Model

89033

Common

Mode

(cont’d)

Y

a

<

i-

_I

0

>

I-

=

L

z

w

-

n

0

z

0

7

3

5.6V

300V

VDIFF

(rms)

-D

IOV

DIFFERENTIAL INPUT VOLTAGE

CASE

2.

Balanced Source with

Common

Mode

on

Both

Sides

AC

Level

DC

Level

3-38

~

Model 89033

LOCAL

(keystrokes)

(program

codes)

DC

Level

LJW

2

DC

LEVEL

s1

T

Measurement

Operation

Description

Pressing the DC LEVEL key causes the Distortion Analyzer

to

measure the differential dc

voltage between the center and outer conductor of the INPUT connector or, for Option

001

only, the center conductors of the (rear-panel) INPUT connectors. Voltage common

to

both

high and low inputs are rejected. See the following Warning and Caution.

To avoid the possibility

of

hazardous shock on standard instruments (those

without Option

OOl),

do not apply more than 42Vpeak to the outer conductor

of

the BNC INPUT connector when the FLOAT switch is

in

the FLOATposition.

Do

not apply more than

300

Vrms

(either differential, common-mode,

or

a

combination) to the INPUT connector(s).

Procedure

To make a dc level measurement, press the

S

(Shift) key, then the DC LEVEL key. The

voltage can be expressed in either volts,

or,

if the voltage is positive, in dBm (that

is,

dB

relative

to

1

milliwatt into

600Q).

To obtain a display in am, press the LOG/LIN key.

To

return to linear, simply press the LOG/LIN again.

If

the dc level

is

to be displayed

relative

to

a reference level, refer

to

RATIO and LOG/LIN.

To measure the dc level at the INPUT connector:

Example

Program Code

Indications

Measurement

Technique

Comments

When dc level is selected, the LEDs within the DC LEVEL key and the

S

(Shift)

key will

light. The right display shows the dc level with the appropriate units. The Distortion

Analyzer automatically ranges for maximum resolution and accuracy. In the dc level

measurement mode, the left display

is

blanked even though

an

ac signal may be present.

In the dc level measurement mode the Distortion Analyzer automatically sets the input

attenuation and the gain of the input amplifier

so

that the signal amplitude lies within the

proper range of the dc voltmeter. The

signal

is then measured by the dc voltmeter and after

correction for input gain and attenuation, displayed in appropriate units.

In the dc level measurement mode only the ac component of the input signal

is

coupled to

the MONITOR output. The ac component also affects the input gain.

Common Mode

RATIO and LOG/LIN

Special Functions

3-39

Operation Model 89033

Default Conditions and Power-up Sequence

Description

When

first

turned on, the Distortion Analyzer performs a sequence of internal checks after

which the instrument

is

ready to make measurements. During the power-up sequence, all

front-panel indicators light

to

allow the operator to determine if any are defective. After

approximately four seconds, this sequence is completed and the Distortion Analyzer is preset

as follows:

MEASUREMENT

..............

AC LEVEL

DETECTOR

....................

RMS

LP FILTER

....................

LOW PASS 80 kHz

HPPeighting BP Filter

.........

Off

RATIO

........................

Off

Ratio Reference

.................

0

LOG/LIN

......................

LIN (see

RATIO

and

LOGILIN

Detailed

Operating Instruction)

Left Display

....................

Input Frequency

Right Display

...................

Input AC Level

Service Request Condition

........

HP-IB Code Error Only

Trigger Mode

...................

Free Run (Code

TO)

Status Byte

.....................

Cleared

Special Functions

...............

All Special Functions off

or

in their zero suffix,

except Service Request Condition which

is

set

to

22.2

(HP-IB Code Error).

NOTE

The FLOAT switch is set

manually.

Ratio and LOG/LIN

Service Request Condition

3-40

Model 89033 Operation

Detector Selection

(Special Function

5)

Description

Procedure

The Distortion Analyzer contains a wideband, true rms

or

average-responding voltmeter

with high accuracy and sensitivity. The Distortion Analyzer can be switched to have either

a true rms

or

averaging detector response.

To select the AVG Detector, press the AVG/RMS key. The key light will light to indicate

average detection. To select the RMS Detector, press the AVG/RMS key again. The

key

light will extinguish, indicating true rms detection.

Example

Program

Code

I

Detector

1

A0

or

5.0SP

Program Code

Indications

Measurement

Technique

Comments

Code A0

is

the HP-IB code

for

RMS

Detector.

A1

is the HP-IB code for AVG Detector.

For fast

or

slow detection selection (either rms

or

average), enter the following HP-IB codes:

5.0SP for fast rms detection,

or

5.1SP for slow rms detection.

For

average detection, enter

the following HP-IB codes: 5.2SP for

fast

average detection,

or

5.3SP for slow average

detection.

When 5.0SP

or

5.1SP is entered, the light in the AVG/RMS key will go out

if

it

is

on.

When 5.2SP

or

5.3SP is entered, the light in the AVG/RMS key will light indicating average

detection has been selected.

When measuring complex waveforms

or

noise, a true

rms

detector will provide a more

accurate rms measurement than an average-responding detector which has been calibrated

to indicate the rms value of a sine wave. For a sine wave, both the true rms and the

average-responding detectors give correct rms readings. However, when the signal is a complex

waveform,

or

when significant noise

is

present, the average-responding detector reading can

be in error. The amount of error depends upon the particular signal being measured.

For

noise, an average-responding detector reads low.

Many ac voltmeters employ an average-responding detector.

For

those applications requiring

the use of an average-responding detector, press the AVG/RMS key

for

average detection.

AC Level

Distortion

Distortion Level

SINAD

3-41

Operation Model

89033

8

1-999

Display

Level

in

Watts

19.OSP

19.NNNSP

(where

NNN

corresponds

to

the

load

resistance

in

ohms.)

(Special Function

19)

Description

The measurement mode can be set

to

read the ac input power level in watts into a specified

external load resistance by using Special Function 19 through HP-IB. The range

of

the

selectable load resistance (in ohms) is an integer value from

1

to

999.

Procedure

To set the measurement to display the ac level in watts into a specified resistance, enter

the corresponding

HP-IB

code.

Resistance

(0)

Program Code

Example

To

set the right display

to

read INPUT signal level in watts into an external 16R speaker:

(program

codes)

19.16SP

Code

LFunction

Program Code

For

HP-IB codes, refer

to

Procedure

above.

indications

The right display

shows

a four-digit readout of the ac power in watts but no units are

indicated. All measurement LEDs

go

off.

Comments

The load resistance in ohms must be an integer (for example, a resistance

of

5.80 cannot

be entered). The decimal point

has

already been used when entering the Special Function.

An attempt to enter a second decimal point

is

ignored.

Remember that the instrument assumes that the input voltage

is

being developed across

the specified external load resistance.

If

an incorrect resistance

is

entered, the readout in

watts is shown for the resistance entered.

Zeros immediately following the decimal point are optional. For example,when setting the

load resistance to

1

ohm, 19.1

is

equivalent to 19.01 and 19.001. However, 19.1 is not

equivalent to 19.10

or

19.100. Note that 19., 19.0, and 19.8 are equivalent (that

is,

they

both specify an

8R

load resistance).

The displayed power level is accurate regardless

of

distortion unless the Distortion Analyzer’s

audio detector is set to average responding.

Neither the RATIO nor the

LOG

function can be used with this Special Function.

Sections

Detector Selection

3-42

Model

89033

Operation

Distortion

Description

The Distortion Analyzer measures distortion by first determining the following value:

noise

+

distortion

signal

+

noise

+

distortion

D=

It

then converts

D

into the appropriate measurement units as follows:

%

units

=

D

X

100%

dB

units

=

2010g

D

The RATIO key can be used to compare the measured results to a predetermined ratio

reference value (refer to

RATIO

and

LOGILIN).

A

distortion measurement can be made on signals from

20

Hz to

100

kHz

and from

50

mV

to

300V

in the single-ended mode (FLOAT switch in the grounded position).

To make a distortion measurement, press the DISTN key. Use the filters

to

limit noise,

hum, spurious signals, etc. The Distortion Analyzer powers up with the LOW

PASS

80

kHz

filter activated.

To measure the distortion of an external source in a

30

kHz bandwidth:

Procedure

Example

a

(program

codes)

M3L

1

Measurement

T-

Filter

Program Code

M3

is the HP-IB code for the distortion measurement.

Indications

When distortion

is

selected, the LED within the DISTN key will light. The frequency and

distortion

of

the input signal are displayed, and the appropriate annunciators are lighted

(see

Description

above).

In the distortion measurement mode, the controller automatically sets the input attenuation

and the gain settings of various amplifiers. This

is

accomplished by measuring the input

signal with the ranging rms detector. This control ensures that the signal amplitude is within

the proper range

for

the input and output detectors. The Input RMS/AVG Detector converts

the ac level of the combined signal

+

noise

+

distortion to dc. The notch filter removes

the fundamental signal. The notch filter automatically tunes to the component whose frequency

is

measured by the counter (usually the fundamental of the input signal). The output detector

converts the residual noise

+

distortion to dc. The dc voltmeter measures both dc signals.

The controller then corrects for the programmed gain and attenuation, computes the ratio

of the two signals

,

and displays the results in appropriate units. The frequency of the input

signal is also measured and displayed.

Measurement

Technique

(Distortion Measurement

Block

Diagram on next page)

3-43

Operation Model

89033

Distortion (cont’d)

COUNTER/

LEFT OISPLAY

(F

REOUENCY)

FREQUENCY

HP/BP

INPUT FILTERS NOTCH

ATTENUATOR FILTER

IINpuTI++

OUTPUT

DETECTOR

RMS/AVG VOLTMETER/ RIGHT OISPLAY

CONTROLLER (AMPLITUDE)

INPUT

RMS/AVG

DETECTOR

(StNtO)

/

INPUT

AMPLIFIER

u1

-

I

RANGING

DETECTOR

RMS

u

-

.

L

Distortion Measurement

Block

Diagram

Comments

Distortion can be measured with either the true

rms

or

average-responding detector. Most

applications specify true

rms

detection.

Sections

Distortion Level

Filters

Notch Tune

RATIO

and LOG/LIN

3-44

Model

89033

Operation

Distortion

Level

Description

This measurement mode can be accessed only via HP-IB. The Distortion Analyzer measures

the distortion level by removing the fundamental of the input signal and then measuring

the ac level of the remaining noise and distortion. The mV and

V

units are displayed

in

the linear mode

or

the values are converted to dJ3m (that is,

dB

relative to

1

milliwatt into

a

6000

load). The RATIO key can be used to compare the measured results to a predetermined

ratio reference (refer to

RATIO and LOGILIN).

To make a distortion level measurement, you must use the HP-IB Distortion Level program

code

S3.

The filters are used to limit the bandwidth. The Distortion Analyzer powers up

with the LOW-PASS

80

kHz filter activated.

To measure distortion level on an external source signal in a

30

kHz bandwidth

Procedure

Example

(program

codes)

S3L1

Measurement

-J7--Filter

Program Code

S3

is

the HP-IB code for distortion level.

Indications

When distortion level

is

selected, the frequency and amplitude

of

the input signal are

displayed, and the appropriate annunciators and DISTN key light will light (see

Description

above).

In the distortion level measurement mode, the controller automatically sets the input attenua-

tion and the gain settings of various amplifiers. This control ensures that the signal amplitude

is

within the proper range for the output detector. The notch filter removes the fundamental

from the input

signal.

The notch filter automatically tunes to the component whose frequency

is

measured by the counter (usually the fundamental

of

the input signal). The output detector

converts the residual noise

+

distortion to dc. The dc voltmeter measures the

signal,

and

the controller corrects for the programmed gain and attenuation. The results are then

displayed in the appropriate units. The frequency

of

the input

is

also measured and displayed.

Measurement

Technique

(Distortion Level Measurement

Block

Diagram on next page)

3-45

Operation

Distortion

Level

(cont’d)

Model

89033

Measurement

Technique

(con t’d)

COUNTER/

LEFT OISPLAY

(FREQUENCY)

FREQUENCY

U

RANGIN6

RWS

DETECTOR

-

1

Distortion Level Measurement

Block

Diagram

Detector Selection

Distortion

Filters

Monitor

Notch

tune

RATIO

and

LOG/LIN

3-46

Model

89033

Operation

All

error messages enabled.

Disable analyzer error messages.

Error

Disable

(Special Function

8)

8.0SP

8.1SP

or

8.3SP

Description

The

Error

Disable Function is used

to

selectively disable operating error messages. Using

the

8.N

Special Function allows the user to enable all operator

error

messages,

or

disable

analyzer errors (measurement related errors).

(program

codes)

Procedure

To selectively disable

(or

enable) operator error messages, enter the corresponding

HP-IB

code.

8.1

SP

Code

TT-Function

Error

Message

Status

Example

To disable the analyzer error messages:

Program Code

For

HP-IB

codes refer to

Procedure

above.

Indications

As

the program code is entered, both displays will blank, and the entered code will flash

in the left display.

Both

displays return

to

the display that

is

appropriate for the currently

selected measurement mode.

Comments

HP-IB

codes

8.1SP

and

8.3SP

perform the same function.

HP-IB

code

8.2SP

can be entered

over the bus, but is ignored.

The error messages can

also

be

selectively disabled

to

prevent unwanted error interrupts to

the

HP-IB

bus controller.

Error

messages are one means by which the instrument safeguards accurate measurements.

When these safeguards are disabled, erroneous measurements can result under certain condi-

tions. This should be kept in mind when operating the instrument with error messages

disabled.

Sections

Error

Message Summary

Special Functions

3-47

Operation Model 89033

Error

Message

Summary

Description

The instrument generates error messages

to

indicate operating problems, incorrect HP-IB

entries,

or

service related problems. The error message

is

generally cleared when the error

condition

is

removed. (Error 31

is

an exception.) The Error Messages are grouped by error

code as follows:

Error

10

through Error

39

and

Error

90

through Error

99.

These are Operating

and Entry Errors that indicate that not all conditions have been met to assure a calibrated

measurement,

or

that an invalid

HP-IB

code sequence entry has been made. The Error

Disable Special Function

(8.N)

can be used to selectively disable certain operating error

messages. Entry Errors require that a new program code entry be made.

Error

65

through Error

89.

These are Service Errors that provide additional service

related information. Service Errors must be enabled

to

appear and

do

not necessarily represent

failures within the instrument. Service Errors are discussed in the Service Section

(8)

of

this manual.

HP-IB

Output

The HP-IB output format for errors is shown below:

+900DDE+05CR

LF

Fixed Data

IJ-

T

-LL

Line

Feed

Fixed Exponent

Format

Error Code Carriage Return

For

example, Error 10 is output

to

the HP-IB as +90010E+05CRLF. This format differs

from normal

data

outputs since normal

data

outputs will never exceed

4

X

109. Once an

error has been input

to

the computing controller, the error code is simply derived by

subtracting 9

X

lo9

from the input number, then dividing the result by 100 000.

Error

Displays

Shown below and on the next page are three types of error displays. The first is typical of

most error displays and is shown as

a

general case. The second and third have specific

meaning and occur often.

This display shows the general error display format. These errors are output to the HP-IB

as

shown under the HP-IB format above.

This display means that no signal has been sensed at the input. This display

is

output to

the HP-IB as Error 96 using the HP-II3 format shown above.

3-48

Model

89033

Operation

Error

Message

Summary

(cont’d)

Error

Displays

(cont’d)

This display means that a signal has been detected,

but

for

various reasons a measurement

result

is

not

yet

available. This display is

never

output

to

the

HP-IB

and

typically indicates

a transitory state

in

instrument operation. After

nine

successive occurrences,

the

display

changes to

Error

31.

Error

31

is

output

to

the

HP-IB

using

the

HP-IB

format shown above.

Error

Messages

The

table

below describes all Operating and

Entry

errors.

The

error code, message, and the

action

typically

required to remove

the

error-causing condition is

given.

Additional information

pertaining to particular errors is also

given.

Code

Error

I

Message Action Required/Comments

10

11

13

14

17

19

26

Reading too large for

display.

Calculated value out of

range.

Notch cannot tune to

input.

Input level exceeds

instrument specifications.

Operating

Errors

This error code indicates that although the required

calculation is within the capability of the instrument, the

result of the calculation exceeds the display

capabilities.

Enter new RATIO reference. Refer to

RATIO and LOG/LIN.

Adjust input frequency to within specified limits. Refer

to Table 1-1.

This error code indicates that the input overload

detector has tripped (not in range hold). This could be

caused by too large an ac signal, or too much ac on a

dc signal.

NOTE

Although error codes

17

and

19

are officially listed here under Operating

Errors, they should be considered rather

as

diagnostic indications.

Internal voltmeter cannot

make measurement.

Cannot confirm external

source frequency.

RATIO not allowed in

present mode.

This error code indicates that the counter has failed to

return a value. This can only be caused by a

malfunction in the counter. Refer to Service Sheet 14.

This error indicates that in notch routine, the frequency

could not be measured, and thus the notch could not

be adjusted. This usually indicates a counter problem.

Refer to Service Sheet 14.

This error code indicates that use of the RATIO key

does not make sense in the current mode. Refer to

RATIO and LOG/LIN.

3-49

Operation Model

89033

~~

65-89

Service-related errors.

Error

Message Summary

(cont’d)

Refer to paragraph

8-1

2,

Service Errors.

Error

Messages

(cont’d)

Action Required/Comments

I

Error

I

Message

Code

30

31

96

20

21

22

23

24

Input overload detector

tripped in range hold.

Cannot make

measurement.

(HP-IB only)

No

signal

sensed at input.

Entered value out of

range.

Invalid HP-IB code

sequence.

Invalid Special Function

prefix.

Invalid Special Function

suffix.

Invalid HP-IB code.

rating Errors (Cont’d)

This error code indicates that the input signal is too

high for the selected range. Use Special Function

1

to

enter a more realistic range setting, or enter AU over

the HP-IB to allow the Distortion Analyzer to seek the

correct input range. Refer to

Automatic Operation.

This error code indication occurs when the input signal

is changing too quickly for the Distortion Analyzer to

make consistent measurements or when the common

mode signal is too large for the Distortion Analyzer.

The

‘I-

-

- -

”

display indicates that the instrument is

trying to make a measurement. After nine unsuccessful

tries, Error

31

is displayed.

This error is sent on the HP-IB when the

‘I-

-”

display

is shown.

Entry Errors

Re-enter new value.

Check for compatibility

of

functions selected.

Check, then re-enter correct Special Function code.

Refer to

Special Functions.

Check, then re-enter correct Special Function code.

Refer to

Special Functions.

Check, then re-enter correct HP-IB code. This error

causes a Require Service message to be sent on the

HP-IB. Refer to Table

3-4

and accompanying text.

Service Errors

Sections

RATIO

and

LOG/LIN

3-50

Model

89033

Operation

LOCAL

(keystrokes)

(program

codes)

Filters

r

High-Pass Filter

7

Low-Pass

Filter7

HIGH

PASS

LOW

PASS

B

High-Pass Filter

!f-

Low

-Pass

F

i

I

ter

(High-Pass, Bandpass, Low-Pass)

Description

Procedure

Example

The optional plug-in high-pass and weighting bandpass, and the LP (low-pass) FILTER

keys cause the respective filters to be inserted into the audio signal path. The filters limit

the measurement bandwith. The high-pass and bandpass filters are inserted before the notch

filter (control of the notch filter is covered in the

Notch

Tune

discussion). The low-pass

filters are inserted after the notch filter. When in use, the high-pass, bandpass and low-pass

filters always affect the signal at the MONITOR output.

Select the desired signal filters by pressing the appropriate keys. Only one high-pass

or

bandpass and one low-pass filter can be in use at a time. To turn a filter off, press the key

again

or

select another filter in the same group. HP-IB codes for the different filter keys

(shown below) turn on the selected filter (defeating others in the group if on). To turn a

high-pass/bandpass

or

low-pass filter off via HP-IB, use code

HO

or

LO respectively,

or

select the alternate filter in the pair.

To select the left high-pass

or

bandpass filter and the

30

kHz low-pass filter:

Indications

Comments

Program Program

Code

@@

High-Pass/Bandpass Filter Code Low-Pass Filter

Both

off

(750

kHz low-pass)

Low Pass

30

kHz

Left High-Pass

or

Bandpass Filter

Right High-Pass or Bandpass Filter H2 Low Pass

80

kHz

L2

When a filter is activated (by either automatic

or

manual selection), the

LED

within that

filter key will light.

Two plug-in positions within the instrument permit the Distortion Analyzer to be configured

with various high-pass

and

band-pass filter combinations. The optional plug-in filter assem-

blies include a

400

Hz High-Pass (used

to

filter out

50/60

Hz

hum, and squelch signals),

and CCITT, CCIR, CCIR/ARM,

“A”

Weighting, and C-Message Weighting Bandpass Filters.

These weighting bandpass filters are all psophometric in nature; each filter characteristic

approximates the response of human hearing according to separately established standards.

These optional plug-in filter assemblies may be inserted in either the left-most

or

right-most

key position, according to the filter option number.

3-51

Model

89033

Operation

Filter

400

Hz

high pass

CClTT

weighting bandpass filter

CClR

weighting

bandpass filter

C-Message weighting bandpass filter

CCIR/ARM

weighting bandpass filter

“A

weighting bandpass filter

Filters

(cont’d)

Left-Most Key Position

Filter Option Number Right-Most Key Position

Filter Option Number

01

0

050

01

1

051

01

2

052

01

3

053

01

4

054

01

5

055

(High-Pass, Bandpass, Low-Pass)

Comments

(cont’d)

The selected filters are always in the path of the audio signal.

With all filters off, the

3

dB

measurement bandwidth

is

approximately

10

Hz

to

750

kHz.

The high-pass

or

bandpass filters affect the signal being counted however, the low-pass

filters do not. Repeating the HP-IB command

to

turn on

a

specific fdter has no effect (that

is, the filters cannot be toggled on and off using the same HP-IB command).

The individual filter characteristics are given in Table

1-1,

Specifications

and in Table

1-2,

Supplemental Information.

The optional, weighting bandpass plug-in filter assemblies weights the frequency response

of the Distortion Analyzer as shown in their respective curve plots.

I

m

0

-

Y

Y)

z

0

a.

Y)

W

a

t15

t10

t5

0

-5

-10

-15

-20

-25

-30

-35

-40

-45

-50

-55

10

FREQUENCY

(Hz)

CCITT

and

400

Hz High-Pass Filter Plot

3-52

Model

89033

Operation

Filters

(cont’d)

(High-Pass, Bandpass, Low-Pass)

t15

+lo

t5

0

-5

-10

-15

-20

-25

-30

-35

-40

-45

-50

-55

10

FREOUENCY

(Hz)

CCIR and CCIRIARM Weighting Filter Plot

m

0

-

W

u)

z

0

n

In

W

a

FREQUENCY

(HZ)

“A”

Weighting and “C”-Message Weighting Filter Plot

3-53

Operation

Model

89033

Filters

(cont’d)

(High-Pass, Bandpass, Low-Pass)

AC

Level

Distortion

Distortion Level

SINAD

3-54

Model

89033

Operation

Float

Description

To minimize measurement errors caused by ground loops, the analyzer input can be floated.

Floating the input improves rejection of low frequency and common mode signals (for

example, line-related hum and noise). The front-panel FLOAT switch determines whether

the input is floating

or

single-ended. When in the float mode, the analyzer input

is

fully

balanced.

To avoid the possibility

of

hazardous shock on standard instruments (those

without Option

001))

do not apply more than

42V

peak to the outer conductor

of

the BNC INPUT connector when the FLOAT switch

is

in

the FLOATposition.

Do

not apply more than

300

Vrms (either differential, common-mode,

or

a

combination) to the INPUT connector(s).

Procedure

To float the analyzer input, set the FLOAT switch to the FLOAT position. In the float

mode the center conductor is the High Input, and the

outer

conductor is the Low Input

that

is

isolated from chassis ground. In the single-ended mode (the FLOAT switch in the

grounded position) the outer conductor is connected directly to chassis ground.

The INPUT BNC connector allows the attachment

of

a shielded cable in the single-ended

mode, which minimizes electromagnetic interference (EMI). This is important if the Distortion

Analyzer

is

operated near a transmitter,

or

in

the presence

of

large RF signals.

When the FLOAT switch

is

in the grounded position, the outer conductor of the connector

is

connected

to

chassis ground.

If

EM1 shielding

is

not critical, banana-type connectors can be used. For Option

001)

two

BNC-to-banana adapters are supplied with the instrument

to

convert the BNC input and

output

to

dual banana with standard 3h-inch spacing. The adapters connect the conductor

of the banana connector to the center conductor of the BNC connector. These adapters are

normally used when the FLOAT switches are set in the FLOAT position.

Comments

DEVICE

FNDER

TEST,

8903E

Effect

of

Multipoint Ground System (FLOAT Switch Closed)

3-55

Operation Model

89033

Float

(cont’d)

Comments

(cont’d)

One major source of

error

which must be considered when measuring low level ac signals

or

when making low distortion measurements

is

error introduced by ground loops. The figure

above illustrates a typical measurement setup using the Distortion Analyzer. In the figure

the system common line

is

connected

to

chassis

or

earth ground at two separate points: the

chassis

of

the Distortion Analyzer and the common point

of

the device under test. Since

two physically separate ground points are seldom

at

the same ground potential, current will

flow in the system common line. Due

to

conductor resistance

(RC)

in the system common

line, the current causes a voltage drop. This voltage drop (a common mode voltage) sums

with the signal under measurement and can cause erroneous readings. Grounding the system

common line

at

a

single point minimizes the effect of common mode voltages caused by

ground loops. Floating the Distortion Analyzer input circuitry isolates the outer conductor

of

the Distortion Analyzer from chassis ground. Thus, the Distortion Analyzer input circuits

are grounded only through the device under test. Note that the system common line is now

grounded at

a

single point.

3-56

Model

89033

Operation

Description

Procedure

Hold

Decimal

Point

(Special Function

4)

The position of the decimal point in the right display can be held in a specific location by

using Special Function

4.

To hold the decimal point in the right display to a specific position, enter the corresponding

HP-IB program code.

Decimal

Hold Position

I

Program

Code

1-

Automatic Selection

DDDD.

V

Range*

DDD.D

V

Range

DD.DD

V

Range

D.DDD

V

Range

0.DDDD

V

Range"

DD.DD

rnV

Range

D.DDD

mV

Range

0.DDDD

rnV

Range"

4.0SP

4.1 SP

4.2SP

4.3SP

4.4SP

4.5SP

4.6SP

4.7SP

4.8SP

I

'The decimal point does not appear on the display. It is

shown to establish the position it would appear in the

numeric value

of

the readout.

"The zero does not appear on the display. It is shown

to clarify the position of the decimal point.

Example

To hold the decimal point after the first digit of a mV Range (D.DDD mV):

Program

Codes

Indications

Comments

(program

codes)

4.7SP

Code

1

-L

Function

For HP-IB codes refer to

Procedure

above.

As the program code

is

entered, both displays will blank, and the entered code will flash

in the left display. The right display will show the amplitude with the decimal held in the

position requested. The left display provides the normal information associated with the

selected measurement mode.

It

is possible

to

use the Hold Decimal Point Special Function to set the display for a readout

that exceeds the resolution of the instrument. For example, in the dc level measurement

.mode,

4.7SP

will set the display

to

a mV range. In this case, the three digits following the

decimal point will always be zeros, and are not significant digits in the amplitude readout.

Automatic Operation

Special Functions

3-57

Operation Model 89033

Hold

Settings

(Special Function

9)

Description

The Hold Settings Special Function is used

to

freeze the instrument in the presently selected

settings for the input level ranges, the post-notch gain, the decimal point position, and the

notch tuning.

Procedure

To hold the presently selected settings for the functions above, enter the HP-IB program

code 9.OSP.

Example

To

hold the present settings

of

the specified functions:

(program

codes)

9.OSP

TT

CodeJ

LFunction

Program Code

For

HP-IB code, refer to

Example

above.

Indications

As the program code is entered, both displays will blank, and the entered code will appear

in the left display. The displays will then show the normal readings for the currently selected

measurement mode.

Comments

Using Special Function

9

is

equivalent to entering the following special functions through

the HP-IB bus:

l.N Input Level Range (Except

DC

Level)

2.N

Input Level Range

(DC

Level Only)

3.N Post-Notch Gain

4.N

Hold Decimal Point (Right Display Only)

6.1

Hold Notch Tuning

For

Special Functions

1

through

4,

N is set equal to the currently selected value that the

instrument is using

for

that function. These values can be read by using the Special Special

Display (refer

to

Special

Functions).

Note that using the Hold Settings Special Function can cause inaccurate measurements

under some circumstances.

Once settings have been held by the Hold Settings Special Function, one

or

more of them

can be reset to their automatic modes by issuing the

0

suffix code

of

the corresponding

Special Function code.

As

an example, Hold Settings places the instrument in hold notch

tuning mode. Use

6.0

SP

to re-enter the automatic notch tuning mode.

Sections

Special Functions

3-58

Model

89033

Description

Procedure

Indications

Talk

Address

Char-

acter

Operation

HP-lB

Address

(Special Function

21)

The Distortion Analyzer’s present HP-IB address can be displayed by using the front-panel

S

(Shift) LCL keys (for the decimal display). This display

is

of the form “Addr=” (in the

left display)

“NN”

(in the right display), where

“NN”

is

the HP-IB decimal address. The

address set at the factory

is

28 (11100

in binary). The HP-IB address can also be displayed

using Special Function

21.

Information on Special Function

21

is

found in

Comments,

below.

To display the HP-IB address in decimal, key in the

S

(Shift) LCL keys.

To display the HP-IB address in decimal:

Listen Decimal

Address Equiva

Char- lent

acter

LOCAL

(keystrokes)

Assuming the same address, the following will be displayed

A

list of the allowable addresses for the Distortion Analyzer

is

given below:

-

A5

0

-

Address Switches

-

A4

0

1

-

A3

0

1

0

1

-

A2

0

1

0

1

0

1

0

1

-

A1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

Talk

Address

Char-

acter

@

A

B

C

D

E

F

G

H

I

J

K

L

M

N

0

-

Listen

Address

Char-

acter

-

Decimal

Equiva

lent

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

-

I

-

A5

1

-

...

......

.

::5qp$

. .

...

(...

.+:.:.:

.:.:.:.:,

,:..../

.........

:x

.....

.

...

,

..Ip

Address Switches

Program

Codes

For HP-IB codes refer to the Program Code table under

Comments

following.

3-59

Operation Model

89033

Binary

Decimal

HP-IB

Address

(cont’d)

21.0

SP

21.1

SP

(Special

Function

21)

0

’

Comments

The HP-IB address display

is

continuously updated. This makes setting the address easy

since the result of changing a switch setting

is

immediately visible on the display. For

information on setting the

HP-IB

address of the Distortion Analyzer, refer to Section

2

of

this

manual.

The factory-set address

is,

as

shown in the examples, decimal 28. The

T

and

L

bits

are

set

to

0.

The

S

bit powers up at

0.

T

L

S

NOT NOT NOT

TALK LISTEN REQUESTING

ONLY ONLY SERVICE

TALK LISTEN REQU ESTlNG

ONLY ONLY SERVICE

To

clear the display (from the instrument front panel), press the LCL key, then any function

key. The instrument reverts to the new measurement mode.

The HP-IB address can

also

be displayed via Special Function

21.

Since Special Functions

can only be executed via HP-IB, the instrument’s HP-IB address must be known prior

to

its use. The primary value of using

HP-IB

is

that

the

status

of the Require Service message

can

be

displayed.

To display the HP-IB address via HP-IB, key in the appropriate

HP-IB

program code as

follows:

Display

Format

As

the program code is entered,

it

will appear on the left display. When the HP-IB code

is entered, the top row measurement key lights and annunciators

will

turn off.

If

the

21.0

Special Function

was

entered, the left display will show a binary number of the form

AAAAA

where

AAAAA

is

the HP-IB address in binary. The right display will show a binary number

of the form TLS where the T, L, and

S

have the meaning indicated in the table on the

following page.

If

T

and L are both 1, the instrument is set

to

talk only (talk overrides listen). If all the

A

digits are set to

1

and

T

is

1,

the instrument will be in

talk

status only (that is, output

the status byte only).

(If

all digits

W.TL

are

1

but

S

is

0,

the Remote Interface board

is not installed.) If the

21.1

Special Function was entered, the left display will show the

statement “Addr=” and the right display will show the decimal value

of

the instrument’s

HP-IB address

(28

if it has not been changed).

Special Functions

Remote Operation, Hewlett-Packard Interface Bus

3-60

Model 89033 Operation

Description

Procedure

Input

Level

Range

(DC

Level)

(Special Function

2)

In all measurement modes the input level range can be set to a desired range by using

Special Function

2.N

through HP-IB. The following discussion describes this function

formode only. Refer

to

Input Level Range (Except

DC

Level)

for additionthe automatic

operation mode, the input level range is determined by both the dc and ac level (if there

is one)

of

the input signal.

To

set the input level range to a selected range,

or

to re-enter the automatic selection mode,

the corresponding HP-IB program code.

Input

Level

Range

(Full

Scale)

Automatic Selection

300V

range

64V

range

16V

range

4V

range

Input

Attenuation

40

dB

24

dB

12

dB

0

dB

Example

To

set the input level range to the 16V range:

Program

Codes

Indications

a

Comments

Program

Code

HP-IB

2.0SP

2.1 SP

2.2SP

2.3SP

2.4SP

(program

codes)

Code

YL

F

unction

For HP-IB codes, refer to

Procedure

above.

As

the program code

is

entered,

it

will flash on the left display, which then temporarily

blanks out.

Note

that for all measurement modes except dc level, the left display will return

to show the input signal frequency after the HP-IB code

is

entered.

When the Distortion Analyzer powers up,

or

when Automatic Operation is selected, the

input level range is placed in the automatic selection mode.

If the input level range

is

set such that the input signal level causes the input overload

detector to trip,

Error

30 will be displayed.

Manually selecting the gain

of

the input level circuitry can cause measurement error.

Measurement accuracy is not specified whenever the gain

of

the input level circuitry is

manually selected because the selected gain setting may be less than optimum. It

is

important

to note that error messages indicating invalid measurements due to incorrect gain settings

are not generated unless overload conditions occur. Automatic operation ensures accurate

measurements for all combinations

of

input signals and measurement modes.

Automatic Operation

DC

Level

Input Level Range (Except

DC

Level)

Monitor

Special Functions

3-61

Operation Model

89033

Input Level Range (Except

DC

Level)

(Special Function

1)

Description

In all measurement modes the input level range can be set

to

a desired range by using

Special Function

1

.NN

through HP-IB. The following discussion describes this function for

function for all measurement modes except

DC

Level mode. Refer to

Input

Leuel

Range

(DC

Leuel)

for additional information. The input circuitry consists

of

a programmable

attenuator and two programmable amplifiers. In automatic operation mode, the gain of the

attenuator-amplifier section of the input is automatically set according to the level of the

input signal.

Procedure

To

set the input level range to a selected range

or

to re-enter the automatic selection mode,

enter the corresponding HP-IB program code.

Input Level Range

(Full

Scale) Program

Code

Automatic Selection

300V

189V

119v

75.4v

47.6V

30.0V

18.9V

1 1.9v

7.54v

4.76V

3.00V

1.89V

1.19v

0.754V

0.476V

0.300V

0.1 89V

0.119v

0.0754V

1 .OSP

1.15p

1.25p

1.35p

1.45p

1.55p

1.65p

1.75p

1.85p

1.95p

1.1OSP

1.11SP

1.1 2SP

1.13SP

1.14SP

1.1 5SP

1.1 6SP

1.17SP

1.1 8SP

1.1 9SP

Example

To

set the input level range to the

30.0V

range:

(program

codes)

1.6SP

Code

-7-Z-Function

Program Code

For

HB-IB codes, refer to

Procedure

above.

e

Indications

As

the program code

is

entered, it will appear on the left display. The display returns to

show the input signal frequency.

3

-62

Model

89033

Operation

Input Level Range (Except

DC

Level)

(Cont’d)

(Special

Function

1)

Comments

When the Distortion Analyzer

is

first powered up

or

when Automatic Operation is selected,

the input level range

is

placed in the automatic selection mode.

If

the input level range is

set such that the input signal level creates an overrange condition, an error message will

be displayed. The error message generated depends on instrument settings

and

the input

signal level.

For

example,

if

the input level range is set such that the input signal level

causes the input overload detector to trip,

Error

30

will be displayed. For a complete listing

of

the error messages, refer to

Error

Message

Summary.

Manually selecting the gain

of

the input level circuitry can cause measurement error.

Measurement accuracy

is

not specified whenever the gain

of

the input level circuitry is

manually selected because the selected gain setting may be less than optimum.

It

is

important

to note that error messages indicating invalid measurements due to incorrect gain settings

are not generated unless overload conditions occur. Automatic operation ensures accurate

measurements

for

all combination

of

input signals and measurement modes.

Sections

Automatic Operation

Input Level Range (DC Level)

Monitor

Special Functions

3-63

Operation Model

89033

Monitor

Description

The MONITOR output provides

a

means of monitoring the ac signal into the output

rms

detector. The auto-ranging MONITOR output level is normally a

0.3

to

3

Vrms

signal which

is

proportional

to

the input signal. In ac level and dc level the MONITOR output provides

a

scaled representation of the ac component of the input signal. In SINAD, distortion, and

distortion level the MONITOR output provides a scaled representation of the input signal

with the fundamental removed. The output is dc coupled with a

600R

output impedance,

and a BNC female connector. The MONITOR output can be used to drive other

test

instruments, such

as

an oscilloscope, wave analyzer,

or

spectrum analyzer for further analysis.

Block Diagram

A

simplified block diagram

of

the Distortion Analyzer measurement circuits illustrating the

relationships between the MONITOR output and the other circuit blocks

is

shown below.

The MONITOR output block diagram illustrates the signal path from the INPUT to the

MONITOR output. The diagram

is

that

of

a programmable gain amplifier with a tunable

notch filter. In ac level and dc level, the notch filter is bypassed. In SINAD, distortion,

and distortion level the notch filter

is

switched into the signal path, removing the fundamental

frequency.

/-INPUT STAGE GAIN- /-POST NOTCH GAIN

-\

INTERNAL

PLUG-IN

HP/EP PROGRAUABLE

PROGRAUABLE

FILTERS GAIN AUPLIFIER

NOTCH GAIN AUPLIFIER

INPUT

ATTENUATOR

(INPUrl)

::

w

OUTPUT

DETECTOR

FILTERS

INPUT

AWPLIF IER

)I

RUWAVG

-

Monitor Output

Block

Diagram

Comments

The MONITOR output gain and sensitivity (that is, the net signal gain from the INPUT

to the MONITOR output) are dependent on the input stage gain and the post-notch gain.

Both the input stage gain and the post-notch gain

can

be determined by viewing the Special

Special Display (refer

to

Special

Functions).

The input stage gain, and post-notch gain for various instrument settings are listed in the

tables below.

3-64

Model

89033

Comments

(Cont’d)

Log

(dB)

0

+20

+40

+60

Operation

Linear

1

10

100

1000

Monitor

(Cont’d)

Special Special

Display

1.”

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

1.10

1.11

1.12

1.13

1.14

1.15

1.16

1.17

1.18

1.19

INPUT STAGE GAIN (Except dc)

Input level

Range

300V

189V

119v

75.4v

47.6V

30.0V

18.9V

11.9v

7.54v

4.76V

3.00V

1.89V

1.19v

0.754V

0.476V

0.300V

0.1 89V

0.119v

0.0754V

Gain

-40

-36

-32

-28

-24

-20

-1

6

-1

2

-8

-4

0

+4

+8

+12

$1

6

+20

+24

+28

+32

0.01

00

0.01 58

0.0251

0.0398

0.0631

0.1

000

0.1 585

0.251 2

0.3981

0.631

0

1-00

1.58

2.51

3.98

6.31

10.00

15.85

25.1 2

39.81

I

POST-NOTCH GAIN

I

Special Special

Display

3.N

3.1

3.2

3.3

3.4

The measurement system net gain equals the combined gain of the two stages. To calculate

the net gain use the following formulas:

Net Gain (LOG)

=

Input Stage Gain (LOG)

+

Post-Notch Gain (LOG)

or

Net Gain (LIN)

=

Input Stage Gain (LIN)

X

Post-Notch Gain (LIN)

In ac level the MONITOR output is a scaled replica

of

the input signal. The MONITOR

output level

is

calculated

as:

VOut

=

Vi,,

X

Net Gain

where

Vi”

is

the input signal level and the linear net gain is used.

3-65

Operation Model

89033

Monitor (Cont’d)

Comments

(Cont’d)

In SIN

AD,

distortion, and distortion level, the fundamental frequency

is

removed (suppressed)

by more than

80

dB.

The output after the notch filter includes all harmonics of the

fundamental plus any noise, hum, and other spurious signals that may be present. These

signal impurities are amplified and are available at the MONITOR output for further analysis.

The following equations express the MONITOR output level as a function of the parameter

being measured (the displayed reading). (Use linear Net Gain.)

For

distortion:

Displayed Reading (in

7%)

X

Vin

X

Net Gain

100

Vout

=

or

For

distortion level:

Vou,

=

Displayed Reading (in volts)

X

Net Gain

or

v

=

1ODisplayed Reading (in

dBm)/PO

x

Net Gain

out

For

SINAD:

100

Displayed Reading (in

%)

x

Vin

X

Net Gain

vout

=

or

V

=

10-iDisplayed Reading

(in

dB)1/20

x

V

x

Net Gain

out

in

In

the above equations

Vout

is

the MONITOR output level as measured with a true

rms voltmeter and

Vin

is

the input signal level.

The MONITOR output does not respond

to

dc signals presented at the INPUT.

In

the dc level measurement mode only the ac components

of

the input signal are presented

at the MONITOR output.

Sections

DC Level

Distortion

Distortion Level

Input Level Range (DC Level)

Input Level Range (Except DC Level)

3-66

Model 89033 Operation

Automatic

Notch

Tuning

[

:oldNoih

Tuning

Notch

Tune

6.0SP

or

NO

6.1SP

or

N1

(Special Function

6)

Description

In SINAD, distortion, and distortion level modes, the Distortion Analyzer automatically

tunes the notch filter to the input frequency. By means of keyboard entry using the NOTCH

key, the notch filter can be held to the current notch filter frequency setting.

To freeze the notch filter, press the NOTCH TUNE key. To return to the automatic tuning

mode, press the NOTCH TUNE key again,

or

enter the HP-IB program code NO

or

6.0SP.

Procedure

LOCAL

(keystrokes)

(program

codes)

Notch

Tune

Notch

Tune

i.1

N1

Function

T

or

Code

Y?-

Function

4

Program Code

1-1

Example

To freeze the notch filter, press NOTCH TUNE:

Codes

The above procedure gives the HP-IB codes

NO

and N1 for the Notch Tuning function.

Notch Tuning may also be controlled over HP-IB with Special Functions 6.0 and 6.1.

Indications

When the NOTCH TUNE key

is

pressed, the LED within the NOTCH TUNE key will

light, indicating the notch filter

is

on. Pressing the NOTCH TUNE key again will turn off

the key light, indicating the notch

filter

is

off.

When either HP-IB

program

code 6.0SP

or

6.1SP is entered, the program code will flash

on the left display. The display blanks, then shows the input signal frequency.

For

HP-IB

program code 6.1SP the light within the NOTCH TUNE key will turn on. The light will

turn off for

HP-IB

program code 6.0SP. When the HP-IB program codes NO or N1

are

used, there

is

no numeric code shown in the left display.

When the Distortion Analyzer first powers up

or

when Automatic Operation is selected

(NOTCH TUNE key light is off), the Distortion Analyzer

is

placed in the automatic notch

tuning mode.

In the automatic tuning mode the Distortion Analyzer counts the frequency of the input

signal, then coarsely tunes the notch filter

to

that frequency. The notch filter is then fine

tuned via circuitry internal to the notch filter. In the hold tune mode, the notch filter is

no longer coarsely tuned, however the fine tune circuitry still remains operational. Thus the

notch filter still automatically tunes, but now over a limited range. In the hold tuning mode

the tuning

or

nulling range of the notch filter is approximately

5%

of the frequency of the

original notch filter setting.

Comments

Sections

Distortion

Distortion Level

SINAD

Special Functions

3-67

Operation Model

89033

Post-Notch Detector Filtering (Except

SINAD)

(Special Function

5)

Description

The Distortion Analyzer normally makes audio measurements using a fast-responding detector.

By means of HP-IB program code entry, additional low-pass filtering can be added

after

the post-notch detector. The additional low-pass filtering (slow detector) is useful in stabilizing

measurements on unstable

or

noisy signals,

or

whenever display jitter

is

considered excessive.

Procedure

To

change the Distortion Analyzer post-notch filtering response from

fast

to

slow

or

vice

versa, enter the corresponding HP-IB program code.

Post-Notch

Detector Response

Fast

RMS

Detector

Slow RMS

Detector

Fast

AVG

Detector

Slow

AVG

Detector

5.0SP

5.1

SP

5.2SP

5.3SP

Example

To enter a slow rms detector response mode:

(program

codes)

Code

-YT-

Function

Program

Codes

For HP-IB codes, refer to the

Procedure

above.

Indications

As the HP-IB program code

is

entered, it will flash on the left display, with the display

returning to show the input signal frequency. When

HP-IB

program code 5.2SP

or

5.3SP

is

entered, the LED within the AVG/RMS key will light

if

not already on.

If

the light

is

already on,

it

will remain on. When HP-IB program code 5.0SP

or

5.1SP

is

entered, the

LED within the AVG/RMS key will turn off

(if

not already off).

Comments

When the Distortion Analyzer is

first

turned on

or

when Automatic Operation

is

selected,

the fast rms detector is selected.

In SINAD, additional low-pass filtering is always used. Fast detection (either

rms

or

avg)

cannot be selected by means

of

HP-IB entry when in SINAD. Slow detection can be used

when

in

SINAD.

Sections

Special Functions

3-68

Model

89033

Operation

Post-Notch

Gain

(Special Function

3)

Description

The overall stage gain of the post-notch circuit can be manually set by HP-IB program

code entry. The gain is selectable from

0

dB

to

60

dB

in

20

dB

steps.

In automatic operation

mode, the instrument will automatically select the optimum post-notch gain.

Procedure

To

manually set the gain of the post-notch circuit,

or

to re-enter the automatic selection

mode, enter the corresponding HP-IB program code.

Post-Notch

Gain

Automatic Selection 3.0SP

0

dB

gain

3.1

SP

20

dB

gain 3.2SP

40

dB

gain 3.3SP

Example

To set the post-notch gain to

40

dB:

(program

codes)

Code

YE

F

" "

Ct

i

on

Program

Codes

For

HP-IB codes, refer to

Procedure

above.

Indications

As

the program code is entered,

it

will flash on the left display, the display then returns

to show the input signal frequency.

Comments

When the Distortion Analyzer

is

first powered up,

or

when Automatic Operation

is

selected,

the Distortion Analyzer is placed in the automatic selection mode.

If

the post-notch gain

is

set such that the input signal level causes the post-notch circuitry

to be overdriven, four dashes will be displayed on the right display. If this overload condition

is

not corrected within nine measurement cycles,

Error

31

will be displayed.

Manually selecting the gain of the post-notch circuit can cause measurement error.

Measurement accuracy is not specified whenever the gain

of

the post-notch circuitry

is

manually selected because the selected gain setting may be less than optimum.

It

is

important

to note that error messages indicating invalid measurements due to incorrect gain settings

are not generated unless overload conditions occur. Automatic operation ensures accurate

measurements for all combination

of

input signals and measurement modes.

Sections

Monitor

Special Functions

3-69

Operation Model 89033

Rapid

Frequency

Count

Description

Rapid Frequency Count mode allows a remote controller

to

partially bypass the Distortion

Analyzer’s own internal controller. The advantage

is

that frequency count measurements

can then be obtained from the Distortion Analyzer much more quickly. The

data

obtained,

however,

is

in a packed binary form, and thus requires additional processing to produce the

final results in hertz

(Hz).

Once the Rapid Frequency Count mode is entered, data will be

placed on the bus in four-byte sequences until the mode is terminated. Rapid Frequency

Count mode is terminated whenever the Distortion Analyzer receives a bus command,

or

whenever it is sent new programming data.

To

use

the Rapid Frequency Count mode, the remote controller must be able to read the

four-byte compacted frequency data using a binary specifier. First, place the Distortion

Analyzer into the ac level measurement mode, set

it

to measure the input signal (that is,

the signal before the notch filter), and to trigger with settling. The HP-IB codes for this

configuration are M146.1SPT3. Next, issue the HP-IB code for Rapid Frequency Count

(RF) and then read the frequency

data

from the Distortion Analyzer. The Distortion Analyzer

does not send carnage return, line feed,

or

any other characters as delimiters.

The frequency data will be in the form shown below:

Procedure

BYTE

1

BYTE

2

BBBB BBBB

r.

BBBB BBBB

I

Jl

260

minus

J

number of

Least

significant

clock Carries digit (

LSD)

of

clock count

Second

least

significant

digit

(2LSD)

of clock count

BYTE

3

BYTE

4

BBBB BBBB

-

255minus

J

number

of

Most significant

Cycle carries digit (MSD) of

clock count

Cvcle

count

To obtain the frequency, compute:

Total clock counts

=

LSD

+

16(2LSD)

+

256(MSD)

+

1024(260

-

BYTE

1)

Total cycle counts

=

Cycle count

+

16(255

-

BYTE 3)

Total cycle counts

Total clock counts

x

(2.106)

Frequency

=

Where:

LSD

=

Least significant digit of clock count

2LSD

=

Second least significant digit

of

clock count

MSD

=

Most significant digit of clock count

Using a BASIC controller such

as

the Hewlett-Packard Model

85B

Desktop Controller, the

computation

is

set up in seven steps as shown below:

10 OUTPUT

728

USING “K

;

“46.1SPT3,RF

20

ENTER

728

USING

“#,E

;

A,B,C,D

30

T=IP(B/16)+16*BINAND(B,15)+16*BINAND(D,48)+1024*(26O-A)

40

E=BINAND(D,15)+16*(255-C)

50

F=lP(E/T*200000000)/100

60 DlSP

F

70

END

3-70

Model 89033 Operation

Rapid Frequency Count (cont’d)

Procedure

Explanation:

Line 10: Places the Distortion Analyzer in the Rapid Count Mode (“46.1SPT3” sets up the

analyzer for transient free operation).

Line 20: Enter the four rapid count bytes using the Binary format “#,B”.

Line 30: Calculate T=total clock counts by bit manipulation and proper weighting.

Line

40:

Calculate

E=total

cycle counts by bit manipulation and proper weighting.

Line

50:

Calculate the frequency

F=(total

cycle count/total clock count)

X

2

106. Note

that the value is multiplied by 100

to

round the integer part and then divide by

100 to round the answer to

2

digits to the right of the decimal.

(cont’d)

Line 60: Displays the frequency count result.

Line 70: Terminates the program.

Using a

HPL

controller such as the Hewlett-Packard Model 9825A Desktop Controller, the

computation

is

set up in seven steps as shown below:

0:

wrt

728,

“RF

1:

frnt,

z,

4b

2: red 728, rl, r2, r3, r4

3:

shf

(r2, 4)

+

16 (band (r2, 15)

+

band (r4, 28))

+

1024 (260

4)

-

r5

4:

band

(r4,

15)

+

16 (255 -r3)

-

r6

5:

2e6r6/r5

-

B

6:

dsp

B

7: end

Explanation:

Line

0:

Place the Distortion Analyzer in the Rapid Frequency Count mode.

Steps 1,2: Establish a format suitable for reading four binary bytes from the Distortion

Analyzer. Take the readings and store the value in four

“r”

variables. The value

stored

is

the decimal equivalent of the binary word.

Shift various bytes around and weight their value by the proper amount (in

accordance with the routine given) to obtain the number of Distortion Analyzer

clock counts. Assign that value to variable

“r5”.

Position bits correctly and weight appropriately to determine the number of cycle

counts. Assign that value to variable 56”.

Since the Distortion Analyzer uses

a

reciprocal counter, the frequency of the

input signal equals the number of input cycles (r6) divided by total time elapsed

during these input cycles. The denominator

is

determined by counting the number

of 2 MHz clock counts that occur during these input cycles and multiplying by

the frequency of the clock

(2

MHz). Total time equals number of clock counts

divided by 2010~.

Line 3:

Line

4:

Line

5:

r5

Total time (seconds)

=

Thus:

Input frequency (Hz)

=

($)X

2

-106

r5/2

-106

Line 6:

Line 7: Terminates the program.

Displays the frequency count result.

3-71

Operation Model

89033

Rapid

Frequency Count (cont'd)

Program

Code

Program Code RF is the

HP-IB

code that initiates the Rapid Frequency Count mode.

indications

When in Rapid Frequency Count mode, the Distortion Analyzer's left display will

show

''-

-

-*

Comments

The major advantage of Rapid Frequency Count mode

is

that

data

can be taken in rapid

sequence and stored in an array in the computing controller. Then, at a later time when

operations

do

not require immediate controller attention, the packed binary data can be

converted into decimal frequency

data.

This way the time required for the Distortion Analyzer

to process the data into decimal frequency is eliminated. This greatly increases its

measurement speed for measuring tone burst sequences.

3-72

Model

89033

Operation

LIN

O/O

YO

%

O/O

RATIO

and

LOG/LIN

LOG

LI

N

LOG

dB

V

or

rnV'

dBrn

into

600Q

dB

V

or

mV

dBrn

into

600Q

dB

YO

dB'

dB

YO*

dB

V

or

rnV'

dBrn

into

600Q

(Special Function

11)

Description

The RATIO key can be used

to

compare any measurement (except frequency and power)

to a reference value. The reference value can be the result

of

a previous measurement. The

LOG/LIN (logarithmic/linear) key can be used to express the results in logarithmic

or

linear

units. The following table shows which units are applicable to the individual measurement

modes:

Measurement

AC

LEVEL

DC

LEVEL

SINAD

DISTN

LEVEL

I

RATIO

On

I

RATIO

Off*

~~~ ~ ~ ~~ ~

*After

initial power on, switching measurement mode results in the configuration

indicated

by

the asterisks. In subsequent operations, the last setting

of

the

LOG/LIN

key

is

remembered for each measurement mode and applied to the new

measurement.

When the RATIO LED is on, the measurement result

is

compared to a reference value.

The reference value can be the result of a previous measurement. The LOG/LIN key allows

any measurement result to be viewed

in

linear

or

logarithmic format.

The Distortion Analyzer stores only one ratio reference at a time. When in ratio,

if

a new

measurement is selected, ratio is disabled.

When returning to the previous measurement, it

is

possible

to

re-enter the ratio mode with

the same factor as before using HP-IB program code 11.0. Additionally, the ratio reference

can be displayed using HP-IB program code

11.1.

To

use the RATIO key, set the display to the desired reference value. This can be done by

adjusting the signal parameter being measured to a reference setting,

or

by entering the

numeric reference via the HP-IB, followed by HP-IB code R1. The entry must be made in

fundamental units (for example, for

a

ratio reference of

60

mV enter

.06

regardless of the

displayed value). The display will show the measurement result relative to the reference

value. The units used with the right display depend upon the setting of the LOG/LIN key

(see table above). Pressing the LOG/LIN key alternates the display between the LOG and

the LIN functions. When the measurement mode

is

changed, the last setting of the LOG/LIN

key

for

that mode is remembered and applied to the new measurement.

To re-enter ratio with the previous ratio reference

or

to

read the reference, enter in the

corresponding HP-IB program code. The special function codes are listed as follows:

Procedure

I

Ratio

Operation

Re-enter ratio

with

the pre-

vious reference.

11 .OSP

I

Read ratio reference.

I

11.1SP

I

Examples

If the display shows

100

mV, to enter this value as the RATIO reference for future

measurements:

3-73

Operation Model

89033

LOCAL

(keystrokes)

a

(program

codes)

Examples

(cont’d)

Ratio

Q

RATIO

R1

Ratio

T

RATIO

and

LOG/LIN

(cont’d)

(Special Function

11)

If

the display shows

O.lOOV,

to compare this to a value of

2V:

(program

codes)

2R1

Data JLRatio

Program

Codes

The HP-IB codes for re-entering ratio

or

for reading the reference are given above. The

e

HP-IB codes for the RATIO and LOG/LIN keys are given below:

Function

LOG

LIN

RATIO Off

RATIO

On

LG

LN

RO

R1

Indications

When the instrument

is

displaying a ratio measurement, the RATIO key lights. The status

of the LOG/LIN key can be determined by observing the the current measurement mode,

the measurement unit lights, and the table above.

The ratio mode can also be used to view an extra digit of resolution when the right display

is

only showing three digits. Depending upon the current value displayed, entering either

lOORl

or

1R1 will cause an unscaled right display readout (that is, the numbers are correct

but the decimal point may not be

in

the correct position). However, an extra digit of

resolution is displayed (for example, if

1.58

was originally displayed, the new display might

indicate

1.576).

Note that the units annunciator will change to

%

and should be interpreted

properly.

Ratio cannot be used with a frequency measurement. Also,

if

a negative reference is entered,

the ratio indication will be displayed in absolute (unsigned) value.

The LOG function cannot be used with

a

reference that is zero

or

negative.

If

the reference

is zero,

Error

20

(entered value out of range)

is

displayed.

If

the reference

is

negative,

Error

11

(calculated value out of range) is displayed.

Comments

Sections

DC Level

Distortion

Distortion Level

Error

Message Summary

SINAD

Special Functions

3-74

Model

89033

Operation

~

(program

codes)

Read

Display

to

HP-IB

(Special Function

20)

20.1SP

Code

1

LF unction

or

YFunct ion

Description

The Distortion Analyzer can be set

to

read the information shown in either the left

or

right

display to the HP-IB bus. Using Special Function

20

through HP-IB allows the operator

to manually determine which display’s information will be placed on the HP-IB bus. This

capability is typically used in the Talk Only Mode when logging

data

to

a

monitoring device.

(Note that when set to Listen Only, the Distortion Analyzer cannot place data on the bus.

If it is set to talk and listen both, front-panel control is relinquished and HP-IB codes

RR

and

RL

determine the

data

output.)

Tu

Bytes

1

I

and 12:

CR,

LF (carriage return, line feed)

Bytes

9

and

10:

Two-digit exponent

Byte

8:

Sign of exponent,

+

or

-

Byte

7:

E

(exponent)

Bytes 2-6: DDDDD, reading from display where

Byte 6 corresponds to the

least

significant digit

of

the reading in the display.

Procedure

To

set the Distortion Analyzer to output data to the HP-IB from either the left

or

right

display, enter the corresponding HP-IB program code.

Display

1

Read

Right

20.0SP

(or

RR)

20.1SP

(or

RL)

Example

To read the left display to the HP-IB:

Program Code

For

HP-IB codes, refer to the table in the

Procedure

above.

Indications

As

the program code

is

entered, both displays will blank, the entered code will flash in the

left display, and four dashes will momentarily appear in the right display. Both displays

then return to the display that is appropriate

for

the current measurement mode.

Sections

3-75

Operation Model

89033

Condition

Service Request Condition

Weight

(Special Function

22)

~~

Data ready

HP-IB

code error

instrument error

Description

The Distortion Analyzer will issue a Require Service message under various circumstances.

For

example, a Require Service message will always be issued

if

an

HP-IB

code error occurs.

Using

HP-IB

program codes, the operator may enable one

or

more conditions

to

cause the

Require Service message to be issued. Whenever the enabled condition occurs, it sets both

the bit corresponding to the condition, and bit

7

(RQS bit) in the Status

Byte.

The bits

set in the status byte and the Require Service message are not cleared unless the status

byte is read (by serial polling), a Clear message

is

received and executed by the Distortion

Analyzer,

or

a ControlIer Reset

or

Controller Clear Service Special Function is performed.

The enabled Service Request conditions are always disabled again whenever a Clear message

is

received and executed by the Distortion Analyzer,

or

whenever a Controller Reset,

or

Controller Clear Service Special Function

is

performed. Automatic operation does not clear

a

Require Service message.

1

2

4

Procedure

To

enable one

or

more conditions

to

cause the Distortion Analyzer

to

issue a Require Service

message, sum the weights

of

the conditions

to

be enabled (from the table below). This

sum

becomes the code suffix of Special Function

22.

Enter the special function code (prefix,

decimal, and suffix) via the

HP-IB

program code. An

HP-IB

code error (weight

2)

will

always cause a Require Service message. This condition cannot be disabled, and

if

the weight

is not summed in, it will be assumed by the instrument.

Example

To set the Distortion Analyzer to send a Require Service message when an instrument error

occurs

(or

when an

HP-IB

code error occurs) first compute the special function suffix by

summing the weights corresponding to those conditions:

(2)

+

4

=

6

Then enter the code:

(program

codes)

Code

YT-

Function

Program Code

Compute the special function code as described under

Procedure

above.

3-76

Model

89033

Operation

Bit

8

7

6

Weight

128

64

32

0

RQS

0

Condition

(always) (always)

Service Request Condition (cont’d)

(Special Function

22)

5

4

3

2

1

16

8

4

2

1

0

Instru-

HP-IB

Data

(always (always) ment Code Ready

Error

Indications

As the HP-IB program code is entered, it will flash on the front-panel display, then the

display returns to show the measurement previously selected. When any enabled condition

occurs, both the RQS bit and the bit corresponding

to

the enabled condition are set in the

status byte, and the SRQ control line on the HP-IB will be set true. The Distortion

Analyzer’s status byte is shown below for reference.

Comments

For

more information

on

HP-IB operation, serial polling, and the Status Byte message, refer

to

the HP-IB discussion titled

HP-IB

Operation

appearing earlier in Section

3

of

this manual.

The HP-IB Address Special Function provides a convenient means to determine at any

time whether a Require Service message

is

being issued by the Distortion Analyzer.

Sections

HP-IB Operation (appears earlier in Section

3)

3-77

Operation Model

8903E

~

LOCAL

(keystrokes)

(program

codes)

SINAD

NOTCH

TUNE

El

Enter

a

clean

external signal.

S

SINAD

-

N1

7-

Measurement

-

Function

Description

The Distortion Analyzer measures SINAD (SIgnal to Noise And Distortion) by first determin-

ing the following value:

signal, noise, and distortion

noise and distortion

S=

S

is then converted into the appropriate measurement units as follows:

%

units

=

S

X

100%

dB

units

=

2010g

S

A

SINAD measurement can be made on signals from

20

Hz to

100

kHz and from

50

mV

to 300V in the single-ended mode (FLOAT switch in grounded position). SINAD measure-

ments are generally made to determine the sensitivity of a receiver. In SINAD mode, the

Notch Filter tunes

to

the Counter Frequency. However, with noisy input signals (SINAD

ratios less than

15

a),

the signal

is

too noisy and unsettled for a good reading. Consequently,

the notch filter jumps around trying to lock on to the input signal. The resulting SINAD

reading will probably be erroneous. The following procedure will allow you to make stable

SINAD measurements at any SINAD ratio.

Procedure

First, input a clean external source signal (SINAD ratio greater than 20

dB),

with Notch

Tune on automatic tuning (NOTCH TUNE off). Press

S

(Shift) SINAD. This allows the

Notch Filter to tune

to

the input frequency. Freeze the notch filter by pressing the NOTCH

TUNE key. This locks the NotchtFilter onto the input frequency. Enter your desired signal

to be measured (SINAD less than

15

dB),

but at the same external source frequency. The

SINAD ratio measurement

is

read on the right display.

Example

To select SINAD:

Program Code

M2

is the HP-IB code

for

the SINAD measurement.

a

Indications

When the HP-IB program code is entered, both displays blank and four dashes are momentar-

ily displayed in the right display. The displays then return to the normally displayed

information

for

the currently selected measurement mode. The

LEDs

in the DISTN/SINAD

and

S

keys light and the appropriate SINAD information for the input signal is displayed.

3-78

Model

89033

Operation

IH*/y

SINAD

(cont’d)

c*

-

c*

-

c/

-

uuuu

Measurement

Technique

In the SINAD measurement mode, the controller automatically sets the input attenuation

and the gain

of

various amplifiers. This is accomplished by measuring the signal with the

ranging rms detector. This control ensures that the signal amplitude is within the proper

range of the input and output detectors. The input detector converts the combined signal

+

noise

+

distortion ac signal to dc. The notch filter then removes the fundamental signal

and the output detector converts the noise

+

distortion ac signal to dc. The dc voltmeter

measures both signals. The controller then corrects for the programmed gain and attenuation,

computes the ratio, and displays the results in the appropriate units. The frequency

of

the

input signal is also measured and displayed.

COUNTER/

LEFT DISPLAY

LFREQUENCY~

SINAD

Measurement

Block

Diagram

Comments

During a SINAD measurement, the output detector uses increased filtering to obtain more

consistent readings in the presence of noise.

SINAD can be measured with either the true rms

or

average responding detector. Most

applications specify true rms detection.

The Distortion Analyzer powers up with Special Function

16.1

active

for

0.0

dB

resolution

at all SINAD ratios. Special Function

16.0

rounds the digital display to

0.5

dB

to reduce

digit flicker,

for

SINAD

ratios less than

25

dB.

Sections

Special Functions

3-79

Operation Model

89033

Special Functions

Description

General Information.

Special Functions extend user control of the instrument beyond that

normally available from dedicated front-panel keys. They

are

intended for the user who has

an understanding of the instrument, and the service technician who needs arbitrary control

of

the instrument functions. Special Functions are accessed via HP-IB entry of the appropriate

numeric code (refer to

Procedures

below). The codes comprise

a

prefix, decimal, and suffix.

Special Functions are disabled by

a

variety of means, depending upon the function. Refer

to the comprehensive listings below

for

actions which clear or disable any Special Function.

Special Functions are grouped by their prefixes into three categories as follows:

Prefix

0

This

is

the Direct Control Special Function and is intended for use in servicing

the Distortion Analyzer. All instrument error messages and safeguards are inactive.

This is discussed in detail in Section

8.

If

the Direct Control

is

entered inadvert-

ently, enter Automatic Operation (AU) over the HP-IB.

Prefixes

1

to

39

These are the User Special Functions which are used during normal instrument

operation when a special configuration, a special measurement, or special informa-

tion is required. All error messages and some safeguards remain in effect unless

the operator disables them. These Special Functions are described below.

Prefixes

40

to

99

These are the Service Special Functions used

to

assist

in troubleshooting an

instrument fault. The functions available are quite diverse

-

special internal

measurements, software control, and special service

tests

and configurations. Most

instrument safeguards are relinquished. These Special Functions are discussed in

detail in Section

8.

If

a Service Special Function

is

entered inadvertently, enter

Automatic Operation (AU) over the HP-IB.

Viewing Special Function States.

The operator-requested settings of Special Functions

prefixed

1

through

8

may be viewed by pressing the

S

(Shift) Notch Tune keys once. This

display

is

called the Special Display.

If

some of these Special Functions are in automatic

modes (generally the 0-suffix setting), the actual instrument settings of these functions may

be displayed by pressing the

S

(Shift) Notch Tune keys a second time while the Special

Display is active. This display

is

called the Special Special Display.

If

desired, these displays

can be cleared by pressing any key except the LCL

or

S

(Shift) keys.

A

summary of User

Special Functions is given on the following pages. Following the summary are procedures

for using Special Display. These displays are also illustrated and explained.

NOTE

The following special functions are ignored: 7.0SP, 7.1SP, 8.2SP, 10.0SP) 12.1SP

through 12.9SP, 13.OSP) 13.1SP, and 17.1SP through 17.9SP. The instrument

will accept the above HP-IB codes (with the possibility of an erroneous display),

but they will not result in a measurement.

3-80

Operation

-

N

Model

89033

Hold Decimal Point

1

Decimal Point not

displayed.

Special Function Summary

(1

of

3)

-

N

1

References

and

Post-Notch

Detector

Response

HP-IB

Code

1 .OSP

l.lSP

1.2SP

1.3SP

1.4SP

1.5SP

1.6SP

1.7SP

1.8SP

1.9SP

1.1 OSP

1.11SP

1.12SP

1.13SP

1.14SP

1.15SP

1.1

6SP

1.17SP

1.1 8SP

1.19SP

Special Function Description

CLEAR”(

Comments

RUTO.

OP.

Code

1

.o

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

1.10

1.11

1.12

1.13

1.14

1.15

1.16

1.17

1.18

1.19

2.0

2.1

2.2

2.3

2.4

3.0

3.1

3.2

3.3

3.4

Name

Input Level

Range (except

DC level)

Automatic selection

300V range

189V range

119V range

75.4V range

47.6V range

30.0V range

18.9V range

11.9V range

7.54V range

4.76V range

3.00V range

1.89V range

1.1

9V range

0.754V range

0.476V range

0.300V range

0.189V range

0.119V range

0.0754V range

-

Y

-

N

~

Automatic Selection

300V range

64V range

16V range

4V range

-

Y

Input Level

Range (DC

Level only)

2.0SP

2.1 SP

2.2SP

2.3SP

2.4SP

-

N

Input Level Range

(DC Level only)

Post-Notch

Gain 3.0SP

3.1 SP

3.2SP

3.3SP

3.4SP

Automatic selection

0

dB gain

20 dB gain

40 dB gain

60 dB gain

-

Y

-

N

Post-Notch Gain

Hold Decimal

Point (right

display only)

4.0SP

4.1 SP

4.2SP

4.3SP

4.4SP

4.5SP

4.6SP

4.7SP

4.8SP

Automatic Selection

DDDD.range1

DDD.D range

DD.DD range

D.DDD range

0.DDDD range2

DD.DD mV range

D.DDD

mV

range

0.DDDD

mV

range2

-

Y

4.0

4.1

4.2

4.3

4.4

4.5

4.6

4.7

4.8

5.0

5.1

5.2

5.3

2

Leading zero not

displayed. Shown

to clarify decimal

point position.

~~ ~

Fast

RMS

Detector

Slow

RMS

Detector

Fast Average Detector

Slow Average Detector

-

Y

Post-Notch

Detector

Filtering

(except in

SINAD)

5.0SP

5.1SP

5.2SP

5.3SP

Nl

I

N

=

No;

-

=

Not

Applicable:

Y

=

Yes; ‘Except the

LCL

Keys

“The

Clear

Key

Function.

I

3-81

Operation Model

89033

Special

Function Summary

(2

of

3)

Special Function Disable

1

References and

HP-IB

Code Description

Name Code

RUTO.

OP.

Notch Tune 5.0

5.1 6.0SP

6.1 SP

-

Y

-

I

Notch Tune

Automatic notch tuning

Hold notch tuning

All

errors enabled

Disable Analyzer errors

(Errors 12-17,31 ,and 96)

NI

1

-

I

Error

Disable

Error Disable 5.0

5.1

or

5.3

8.0SP

8.1SP

or

8.3SP

-

Y

Nl

Hold Settings

I--

Hold Settings

9.0

9.OSP Hold input level ranges,

post-notch gain, decimal

point and notch tuning

at present settings.

Y

~~ ~

11 .OSP

11.1SP

Restore last RATIO

reference and enter

RATIO mode if allowed.

Display RATIO

reference

N

Y

Re-enter Ratio

Mode 11.0

11.1

RATIO and

LOG/LIN

YI

Time Between

Measurements 14.0

14.1

14.0SP

14.1SP

Minimum time between

measurements

Add 1s between

measurements

-

Y

Measurement

_t----

SINAD

SINAD Display

Resolution 16.0

16.1

16.0SP

16.1 SP

0.01 dB above

25

dB;

0.5 dB below 25 dB

0.01 dB all ranges

-

Y

Nl

Display Level in

T

Display Level

in Watts 19.0

19.NNN

19.OSP

19.NNNSP

Display level as watts

into 8Sl

into

NNNSl

Y

yI

~~

Read Display

to HP-IB 20.0

20.1 20.0SP

20.1 SP Read right display

Read left display N

N Read Display to

HP-IB

I

~ ~~

HP-IB Address 21

.o

21.1

21 .OSP

21.1 SP

Displays HP-IB address

(in binary) in left display;

right display in form TLS

where:

T=l means talk only;

L=l means listen only;

S=l means SRQ.

Displays HP-IB address

in decimal.

Y

I

HP-IB Address

N

=

NO;

-

=

Not

ADDliCable;

Y

=

Yes;

'Except the

LCL

Keys "The Clear Key

Function.

3-82

Model 89033 Operation

(program codes)

Special Function

Summary

(3

of

3)

Code

I

Special

Function

I

HP-I6

Name

Service Request

Description

Enable a condition

to

cause a service request,

N

is

the

sum

of

any

combination

of

the

weighted conditions

below:

1-Data Ready

2-HP-IB

error

4-Instrument error

The instrument powers

up

in

the

22.2

state

(HP-IB

error).

Disable

I

References

and

AUTO.

OP.

N

I

N

=

No:

-

=

Not Applicable;

Y

=

Yes; 'Except

the

LCL.

S

(Shift),

and

Numeric

Keys

"The Clear Key

Function.

Procedure Entering Special Functions.

To use a special function, enter the corresponding HP-IB

program code.

Special Display.

To display the user-requested modes of Special Functions

1

through

8,

press the

S

(Shift) key then the NOTCH TUNE key

or

enter the HP-IB code SP. The

digit position (noted beneath the displays) corresponds to the special function prefix, and

the number displayed in that position corresponds to the special function suffix.

Special Special Display.

To determine the actual instrument settings of functions prefixed

1

through

8,

press the

S

(Shift) key and the NOTCH TUNE key once while Special Display

is

active

or

enter the HP-IB code

SS.

(If

the Special Display described above

is

not in

effect, press the above mentioned keys twice

to

get this display.) The digit position corresponds

to the function prefix, and the number displayed in that digit corresponds to the function

suffix.

Examples Entering Special Functions.

To set the post-notch gain to

40dB:

Special Display.

When the

S

(Shift) and NOTCH TUNE keys are pressed, the following

display results,

(=

PREFIXES)

1

2

3

4

5

6

7

8

3-83

Operation Model 89033

Special

Functions (Cont’d)

Examples

This display indicates that the following Special Functions were selected by the operator:

(cont’d)

Code

-

1.17

2.0

3.0

4.6

5.0

6.1

8.1

-

Special Function

Name

Input

Level Range (Except

DC

Level)

Input

Level Range

(DC

Level only)

Post-Notch Gain

Hold Decimal Point

Post-Notch Detector

Notch Tune

Error Disable

User-Requested Setting

0.189V range

Automatic Selection

DD.DD

mV

range (right display only)

Fast

RMS

Detector Filtering (Except

in

SINAD)

Hold notch tuning

Disable analyzer errors

Special Special Display.

When the

S

(Shift) and NOTCH TUNE keys are pressed again

while the Special Display is active and the following display results, the actual instrument

settings are tabulated below.

(=

SUFFIXES)

(=

PREFIXES)

-

Code

1.17

2.1

3.4

4.6

5.0

6.1

8.1

-

1

2

3

4

5

6

7 8

Special Function

Name

Input

Level Range (Except

DC

Level)

Input

Level Range

(DC

Level only)

Post-Notch Gain

Hold

Decimal Point

Post-Notch Detection Filtering

Notch Tune

Error Disable

Actual Instrument Setting

0.189V range

300V range

60 dB

Range

DD.DD

mV

range

Fast

RMS

Detector (Except

in

SINAD)

Hold

notch tuning

Disable analyzer errors

Code

HP-IB Codes

for

the special functions are summarized in the

Special

Function Summary

above.

Indications

Entering Special Functions.

As

the HP-IB program code

is

entered, both

displays will blank, and the entered code will flash in the left display.

Four

dashes will momentarily appear in the right display, then are replaced

with the appropriate reading

for

the selected measurement mode.

3-84

Model 89033 Operation

Special Functions (Cont’d)

Comments

If

a User Special Function (prefixes

1

to 39) has a suffix of zero, the zero need not be

entered. For example,

5.0

SP

equals

5.

SP.

(However,

1.1

SP

does not equal 1.10

SP.)

If

when entering an HP-IB program code, Error

21

(invalid key sequence) is displayed, the

special function requested has not been executed. Entry of invalid special function suffixes

results in display of Error 23. For additional information on Direct Control Special Functions

(prefix

0)

or Service Special Functions (prefixes

40

to

99)

refer to Section

8.

Sections

Default Conditions and Power-up Sequence

Special Function Summary table (under Description above)

3-85

Operation

Minimum

Add

1

second

Model

8903E

~~~

14.0SP

14.1SP

Description

Procedure

e

(program

codes)

Example

Code

YT-

Function

Program

Codes

Indications

Time Between Measurements

(Special Function

14)

A

one-second delay between measurements can be added using Special Function

14.

It

can

be used to to allow the device under test to settle before making the measurement.

To

add

or

delete the one second time delay between measurements, enter the corresponding

HP-IB

program code.

Time

Delay

Between

Measurements

To

set a one second time delay between measurements:

For

HP-IB

codes, refer to

Procedure

above.

As the program code is entered, both displays will blank and the entered code will flash in

the left display. Both displays then return to the display that

is

appropriate

for

the currently

selected measurement mode.

Automatic Operation

Special Functions

3-86

Model

8903E

Performance Tests

Section

4

PERFORMANCE TESTS

4-1.

INTRODUCTION

The procedures in this section test the instrument’s electrical performance using the specifications

of

Table

1-1

as the performance standards. AI1 tests can be performed without access to the interior of the instrument.

A

simpler operational test is included in Section

3

under

Bclsic Fienctional

Cheeks

(paragraph

3-10).

The Basic

Functional Checks also test

the

instrument’s ability

to

function in the automatic mode (which is not thoroughly

checked by the Performance Tests).

NOTE

Unless

otherwisc nottd,

no

warm-icp pcriod

is

rtqicired for these

tt’sts.

Line

vollagtp rniist

he

within

+5%

and

-1090

ojthe spt~i*l/ied inpict voltage

(100,

120,

220,

or

240

Vac)

if

the performance tes/s art’

to

be

considtwd valid.

4-2.

EQUIPMENT

REQUIRED

Equipment required for the performance tests is listed in Table

1-3,

Rec*omrncndt>d

Tcsf

Eqiriprncwt

in Section

1

of this manual. Any equipment that satisfies the critical specifications in the table may be substituted for the

recommended model(s).

NOTE

The perJormance

tests

arc ha.5t.d

on

the asslimption that the rtx*omrntwdcd

k’sf

quip-

mcnf

is

used.

Siihstif itling altcmafc

fesl

cqiiipmcwf

may reqirirr modgfication

of

sornc

proccd

i

r

res.

4-3.

TEST RECORD

Results

of

the performance tests may be tabulated on the Test Record shown in Table

4-1

at the end

of

the procedures. The Test Record lists all of the tested specifications and their acceptable limits. The results,

recorded at incoming inspection, can be used for comparison

in

periodic maintenance and troubleshooting

and after repairs or adjustments.

4-4.

CALIBRATION CYCLE

This instrument requires periodic verification of performance. Depending

on

the use and environmental con-

ditions, the instrument should be checked using the following performance tests at least once every year.

4-5.

ABBREVIATED

PERFORMANCE

TESTING

No

abbreviation of performance testing is recommended.

4-

1

Performance Tests

Characteristic

AC

LEVEL

Accuracy

Model 8903E

PERFORMANCE TESTS

Performance Limits Conditions

32VO

39%

50

mV

to

300V;

20

Hz

to

20

kHz

50

mV

to

300V;

20

kHz

to

100 kHz

0.3 mV

to

50

mV;

20

Hz

to

100

kHz

4-6.

AC

LEVEL

ACCURACY PERFORMANCE

TEST

SPECIFICATION:

DESCRIPTION:

For each ac range, ac level accuracy is determined

by

measuring the output

of

an ac calibrator. In addition, for

the lowest range, the output

of

an audio synthesizer is set

to

the lowest level of the just-completed calibration.

This level

is

established as a ratio reference, then the signal is attenuated

by

a precise amount.

The procedure is run with the outer conductor of the input connector grounded, then with the inner conductor

grounded and the signal applied

to

the (ungrounded) outer conductor.

A

controller with HP-IB is recommended for this test since it provides the

most

convenient method for setting

level ranges. However, an alternate method, not requiring a controller, is also mentioned

in

the procedure.

Voltagcs

iip

fo

300

Vrms will

be

applied

to

fhc

Distortion Analyzer's inpirf connmor.

EQUIPMENT:

AC Calibrator..

..............

HP 754A and HP 746A, Datron 4200,

or

Fluke

5200A and Fluke 5215A

Audio Synthesizer

.....................................

HP

3336C

Controller with HP-IB

............................

HP

85B

Opt 007

Dual Banana to

BNC

Adapter

.........................

HP

101

10B

Dual Banana

to

BNC Adapter

.......................

HP 1251-2277

.....................

PROCEDURE

NOTE

The

Distortion Analyzt~'.~ HP-IB addrtw is asslimed

IO

be

728.

All

HP-IB command.s

are given

in

BASIC.

High-Level, High-Input AC Level Accuracy

1. Connect the HP-IB controller

to

the Distortion Analyzer. Key in and execute the following command:

O'JTPUT

728;

"41

.OSP

LO"

to

initialize the instrument and

set

the

80

kHt

LOW

PASS filter

off.

NOTE

Ifa

confrolkr

is

not

king

iiwd,

swilch

lhc

Dislorfion Analyzrr

to

oirthen

hack

on.

AJivr

powr-tip, press

thc

80

kHz

LOW

PASS

to tirm

if

c$$

4-2

Model

8903E

Performance Tests

PERFORMANCE

TESTS

2.

Set the Distortion Analyzer’s

INPUT

switch

to

ground. Connect the ac calibrator

to

the Distortion Ana-

lyzer’s

INPUT.

3.

Set the ac calibrator to the level indicated in the table. (Use the high voltage amplifier where needed.)

Using the controller, key in and execute the Special Function and ratio commands indicated in the table

below. Now set the ac calibrator to the frequency indicated in the table. The right display

of

the Distortion

Analyzer should read within the limits indicated.

NOTE

if

a

controller is not being used, procwd as joIlows:

a.

St>t

the ac calihrator

(lcvel

and jkyircncy) as indicated.

b.

Prtx

S

(Shfl) NOTCH TUNE

S

(Shifr) NOTCH TUNE.

In

the

kji

display. the digit

or digits displayed in position

I

and the digit prtwding it

(if

not

hlankcd) shoiild

agree

with the Special Firnction

sigfjx

of

the controlkr command in the table. (For

example, the display for

1.2SP

shoirld

he

2

in posiiion

I

(the preceding digit hlank).

The display for

1.12SP

shoirld he

I.?

with

2

in position

I

and

I

preceding it.)

c.

Pre.$s

AC

LE

VEL.

Compiite the ratio

of’

fhe wading in the right display

to

ihe

calibrator

set

fing.

The ratio shoiild

he

within the limits indicated in the tahk

Controller

Commands

OUTPUT

728:

“1.1

SP

300R1*’

“1.2SP 150R1”

“1.3SP 100R1“

”1.4SP 70R1”

“1.5SP 45R1”

“1.6SP 30R1”

AC Calibrator

~~~ ~~

Level

(Vrms)

300

150

100

70

45

30

Frequency

(Hz)

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

Minimum

98

96

98

96

98

96

98

Ratio Limits

(“IO)

Actual Maximum

1 02

102

104

1 02

102

1 02

102

1 02

104

102

1 02

104

102

~~

4-3

Performance Tests

Model

8903E

PERFORMANCE TESTS

Controller

Commands

OUTPUT

728;

"1.7SP 15R1"

"1.8SP

1

OR1

"

"1.9SP

7R1"

"1

.lOSP 4.5R1

'I

"1.1

1

SP 3R1

I'

"1.12SP 1.5R1"

"1.13SP lR1"

"1.14SP 0.7R1"

"1.15SP 0.45R1"

"1.16SP 0.3R1"

AC

Calibrator

Level (Vtms)

15

10

7

4.5

3.0

1.5

1

.o

0.7

0.45

0.30

Frequency

(Hr)

20

2

000

20 000

100

000

100

000

20

000

2

000

20

2 000

20 000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2 000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

Minimum

98

96

98

96

98

96

98

96

98

96

98

Ratio Limits

(%)

Actual Maximum

102

104

1

02

1

02

102

104

102

1

02

102

1

02

104

1

02

102

1

02

1

02

102

104

102

1

04

104

1

02

1

02

102

4-4

Model

8903E

Performance Tests

PERFORMANCE TESTS

Controller

Commands

OUTPUT

728:

"1.17SP 0.15R1"

"1.1

8SP

0.1

R1"

"1.19SP 0.07R1"

"0.007R1"

AC Calibrator

~~

Level (Vrms)

0.15

0.1

0

0.07

0.007

Frequency

(Hz)

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

Minimum

98

96

98

96

Ratio Limits

("A)

Actual Maximum

102

1

02

102

104

1

02

1

02

1

02

1

02

1

02

1

02

104

High-Level, Low-Input AC Level Accuracy

4.

On the Distortion Analyzer, set the INPUT switch

to

FLOAT.

5.

Connect the equipment

as

shown

in

Figure

4-1.

Note how the cable connects

to

the Distortion Analyzer's

input through the two adapters. The adapters reverse

the

outer

and inner conductor connections to the

cable.

8903E

DISTORTION

ANALYZER

I

(NOTE THE

ORIENTATION

OF

THE GROUND

TERMINAL.)

1

GROUND INDICATOR

4-5

Performance Tests Model

8903E

PERFORMANCE

TESTS

6.

Set the ac calibrator

to

the level indicated in the table. (Use the high voltage amplifier as needed.) Using

the controller,

key

in and execute the Special Function and ratio commands indicated in the table below.

Now set the ac calibrator

to

the frequency indicated in the table. The right display

of

the Distortion

Analyzer should read within the limits indicated.

NOTE

If

a

controller

is

not

being

iiscd,

follow

the procediire

of

the

Note

in

sfep

3.

Controller

Commands

OUTPUT

728;

"1.6SP 30R1"

"1.7SP 15R1"

"1.8SP

1

OR1

"

"1.9SP

7R1"

"1.1OSP 4.5R1"

"1.1

1

SP 3R1"

"1.12SP 1.5R1"

"1.13SP

1

R1"

AC

Calibrator

Level (Vrms)

30

15

10

7

4.5

3.0

1.5

1

.o

Frequency

(Hz)

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2 000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20 000

100

000

100

000

20

000

2

000

20

2 000

20 000

100

000

Minimum

96

98

96

98

96

98

96

98

96

Ratio Limits

("A)

~

Actual

~~

Maximum

104

1

02

1

02

1

02

102

1

02

102

104

1

02

102

1

02

102

1

02

1

02

104

102

1

02

102

1

02

104

1

02

1

02

102

104

4-6

Model

8903E

Performance Tests

PERFORMANCE

TESTS

Controller

Commands

OUTPUT

728:

"1.14SP 0.7R1"

"1.15SP 0.4541

"

"1.1

6SP

0.3R1"

"1.17SP 0.15R1"

"1.18SP 0.1 R1"

"1.1

9SP

0.07R1"

"0.007Rl"

AC Calibrator

Level

(Vrms)

0.7

0.45

0.30

0.15

0.1 0

0.07

0.007

Frequency

(Hr)

100 000

20

000

2

000

20

2

000

20 000

100 000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2 000

20

2

000

20 000

100 000

100

000

20

000

2

000

20

Minimum

96

98

96

98

96

98

96

Ratio Limits

(%)

Actual Maximum

104

102

1

02

1

02

102

1

02

102

104

1

02

102

1

02

1

02

1

02

104

1

02

1

02

1

02

1

02

102

104

Low-Level, Low-Input

AC

Level

Accuracy

7.

On the Distortion Analyzer, press the

LCL

key

and set RATIO

off.

8.

Replace the ac calibrator with the audio synthesizer. (Leave the adapters as they are.) Set the audio

9.

Set the audio synthesizer to the frequency indicated in the table below. For each setting, perform the

a. Press RATIO if it is

on.

Set the audio synthesizer to

7

mVrms as read

on

the Distortion Analyzer.

b. Decrease the

level

of the audio synthesizer by exactly

26

dB. Note the reading of the right display

of

c. Multiply the reading on the right display by the entry in the table of step

6,

which corresponds to the

sythesizer's level to approximately

7

mVrms as read on the Distortion Analyzer.

following procedure:

Press RATIO.

the Distortion Analyzer.

4-7

Performance Tests Model

8903E

Synthesizer

Frequency

(Hz)

20

2 000

20 000

100

000

PERFORMANCE TESTS

ac calibrator setting of

0.007

Vrms at the current frequency. Divide the result by

100.

The computed

ratio should be within the limits indicated below.

For

example, if the reading in step b was

5.03%

and the corresponding reading of step

6

is

101.5%,

the computed result is

Displayed

Reading

of

Step

b

(YO)

Minimum

Limits

of

Computed Result

(YO)

Actual Maximum

4.81 5.21

5.03%

x

101.5%

=

5.11%o.

100%

Synthesizer Displayed

Frequency Reading

of

(H4

Step

b

(YO)

100

000

20

000

2

000

20

Limits

of

Computed Result

(YO)

Minimum Actual Maximum

4.81 5.21

4-8

Model 8903E Performance Tests

PERFORMANCE TESTS

4-7.

DC

LEVEL

ACCURACY PERFORMANCE

TEST

SPECIFICATION:

DC LEVEL

Accuracy

I

Characteristic

I

Performance Limits

I

Conditions

1

k0.75%

of

reading

400

mV

to

300V

f3

rnV

<400

mV

DESCRIPTION:

The output from a dc standard

is

applied to the input

of

the Distortion Analyzer and the voltage

on

the display

is compared against the output

from

the standard. The procedure is run with the outer conductor

of

the input

connector grounded then with the inner conductor grounded and the signal applied

to

the (ungrounded) outer

conductor.

DC

Standard

Voltage (Vdc)

300

30

3

0.4

0.04

Voitagcs

rip

to

300

Va’c

will

be

applitd to the Diftorfion Analyztd~

inpuf

connecfor.

DC Voltage Limits (Vdc)

Minimum Actual Maximum

297.75 302.25

29.775 30.225

2.9775

3.0225

0.397

0.403

0.037

0.043

EQUIPMENT:

DC Standard..

.

. . . .

.

. . .

.

HP

740B,

Datron

4000,

or

Fluke

893AR

Low-Input

DC

Level

Accuracy

4.

On the Distortion Analyzer, set the

INPUT

switch

to

FLOAT.

5.

Connect the equipment as shown in Figure

4-2.

Note how the cable connects to the Distortion Analyzer’s

input through the two adapters. The adapters reverse the outer and inner conductor connections to the

cable.

4-9

Performance Tests

DC

Standard

Voltage (Vdc)

0.04

Model

8903E

DC Voltage Limits (Vdc)

Minimum

I

Actual Maximum

0.037

I

0.043

PERFORMANCE

TESTS

0.4

3

30

8903E

DISTORTION

ANALYZER

0.397

0.403

2.9775

3.0225

29.775

30.225

DC

STANDARD

(NOTE THE

ORIENTATION

OF

THE

QROUND

TERYINAL.)

QROUND

INDICATOR

6.

Set the dc standard to give the output voltage indicated below.

For

each setting, the right display on the

Distortion Analyzer should read within the limits indicated.

4-

10

Model 8903E

LOW

PASS

FILTER

80 kHz

80

kHz

80 kHz

80

kHz

80 kHz

Off

Performance Tests

PERFORMANCE TESTS

Lii

Actual

4-8.

RESIDUAL DISTORTION AND NOISE PERFORMANCE TEST

SPECIFICATION:

Characteristic

DISTORTION

AND

SINAD

Residual

Noise

and

Distortion

Performance Limits

The higher of

-80

dB

The higher of

-70

dB

The higher

of

-68

dB

or 15pV

or

45

pV

or

45

uV

Conditions

20

Hz to POkHz;

20 kHz to

50

kHz;

50

kHz

to

100 kHz;

80 kHz bandwidth

500

kHz bandwidth

500 kHz bandwidth

DESCRIPTION:

The output of a low-distortion audio oscillator is connected

to

the Distortion Analyzer’s input, and the com-

bination

of

distortion and noise

is

measured at various frequencies and levels. The test measures the distortion

and noise

of

the oscilllator and analyzer simultaneously. If either instrument is

out

of specification, a known,

good oscillator or analyzer can be substituted

to

determine which instrument is at fault.

EQUIPMENT:

Audio Oscillator..

. . . .

.

. .

.

. .

.

. . . .

,

.

HP

339A or HP 8903B

PROCEDURE:

1. Switch the Distortion Analyzer

off,

then back on to initialize

it.

Set the INPUT switch to ground. Connect

the output of the audio oscillator

to

the Distortion Analyzer’s INPUT.

2.

On

the Distortion Analyzer, press DISTN. Set the audio oscillator frequency and level (open-circuit) and

the Distortion Analyzer’s LP FILTER as indicated below. For each setting, the right display should

be

within the limits indicated.

r--

~

Audio Oscillator

Frequency

(Hz)

20

1

000

1

000

1

000

1

000

20

000

50

000

50

000

100 000

100

000

100

000

Level

(V)

3.0

2.5

1.9

0.3

3.0

0.3

3.0

2.5

1.9

its

(%)

Maximum

0.01

0.03

0.04

4-1

1

Performance Tests

Characteristic

DISTORTION

Model 8903E

PERFORMANCE TESTS

Performance Limits Conditions

4-9.

DISTORTION AND SINAD ACCURACY PERFORMANCE TEST

SPECIFICATION:

Accuracy

il

dB

32

dB

20

Hz

to

20

kHz

20

kHz

to

100

kHz

Accuracy

*l

dB

I

i2dB

SINAD

20

Hz

to

20

kHz

I

20

kHz

to

100

kHz

DESCRIPTION:

A signal with a known distortion level is created artificially by summing the outputs from two audio oscillators

at the input of the Distortion Analyzer. The artifical distortion is then measured by the Distortion Analyzer.

To

calibrate the distortion, the second oscillator is set to a harmonic of the low-distortion oscillator, the two

signals are set

to

a common reference level using an external voltmeter with a very flat frequency response,

then the level of the second oscillator is attenuated to obtain a precise ratio.

EQUIPMENT:

Audio Oscillator, Low-Distortion

............

HP 339A or HP 8903B

Audio Oscillator.

......................................

HP 3336C

True RMS Voltmeter

..................................

HP 3403C

PROCEDURE:

1.

Switch the Distortion Analyzer

OK

then back on to initialize it. Set the Distortion Analyzer controls

as

follows:'

INPUT switch

...............................

ground

MEASUREMENT.

...........................

DISTN

LOG

LTN..

....................................

LOG

2.

Connect the equipment as shown in Figure 4-3. The output impedance of both oscillators should

be

50n.

Set the voltmeter to read ac volts. Set the output of the low-distortion oscillator

to

6V

into an open

circuit.

8903E

DISTORTION ANALYZER

1

I

SECOND

AUDIO OSCILLATOR

I

AUDIO OSCILLATOR

TRUE

INPUT

RMS

VOLTMETER

50

OHM

FEEDTHROUGH

TERMINATION

Figlire

4-3.

Disforfion

and

SINAD

A

ccitracy

TtW

Sefiip

4-12

Model

8903E

Second Oscillator Low-Distortion

Frequency

(Hz)

Atten (dB) Frequency

(HI)

200

000

10 100

000

200

000

60

loo

000

Oscillator

300 000

60

100

000

300

000

10 100

000

Performance Tests

PERFORMANCE

TESTS

Level (dB)

Minimum Actual Maximum

-1

2.4 -8.4

-62.0

-58.0

-62.0 -58.0

-12.4 -8.4

3.

Set the oscillator frequencies as indicated below.

For

each frequency setting, perform the following pro-

a. Set the second oscillator level

to

minimum. Note the level of the output of the low-distortion oscil-

b.

Set the low-distortion oscillator amplitude

to

OV.

Adjust the second oscillator’s level for the same

c.

Decrement (that

is,

attenuate) the second oscillator’s output level as indicated.

d. Set the low-distortion oscillator level to

6V.

The display on the Distortion Analyzer should read

cedure:

lator

on

the external voltmeter.

reading as

in

step

a.

within the limits indicated.

Second Oscillator

Frequency

(Hz)

50

4

000

4

000

4

000

4

000

4

000

4

000

4

000

4

000

6

000

6

000

8

000

8

000

10

000

10

000

40

000

40

000

Atten (dB)

10

80

10

20

30

40

50

60

70

80

10

80

10

80

Low-Distortion

Oscillator

Frequency

(Hz)

25

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2

000

20

000

20

000

Level (dB)

-81

.o

-1

1.4

-21

.o

-31

.O

41

.O

-51

.O

-61

.O

-71

.O

-81

.o

-81

.o

-1

1.4

-1

1.4

-81.0

-81

.o

-1

1.4

-1

1.4

-81

.o

Maximum

-9.4

-79.0

-9.4

-19.0

-29.0

-39.0

49.0

-59.0

-69.0

-79.0

-9.4

-79.0

-9.4

-79.0

4-13

Performance Tests

Audio Synthesizer MEASUREMENT

Frequency (Hz) Level (mV) Mode

20

5

AC

LEVEL

20

50

DlSTN

99 900

50

DlSTN

99 900

5

AC

LEVEL

150

000

5

AC

LEVEL

Model

8903E

PERFORMANCE TESTS

Frequency Limits (Hz)

Minimum Actual Maximum

19.99 20.01

19.99

20.01

99 895 99 905

149 980 150

020

4-10.

FREQUENCY ACCURACY AND SENSITIVITY PERFORMANCE TEST

SPECIFICATION:

Characteristic

FREQUENCY

Measurement

Range

Accuracy

Sensitivity

Performance Limits

20

Hz

to

150 kHz

20

Hz

to

100 kHz

f0.004%

3tl

digit

50

mV

5

mV

Conditions

AC

level mode

Distortion and

SINAD

modes

Distortion and SINAD modes

AC

level mode

DESCRIPTION:

The frequency of an audio synthesizer is measured at various levels with the Distortion Analyzer’s counter.

EQUIPMENT:

Audio Synthesizer

.

. . .

.

. .

.

. . .

.

. .

.

. . .

.

. . . .

.

HP

3336C

NOTE

The

audio

synthesizer's

time base accuracy mirst be

4

ppm or btwr.

4-14

Model

8903E

Performance

Tests

PERFORMANCE

TESTS

4-1

1.

AUDIO

FILTERS

PERFORMANCE

TEST

SPECIFICATION:

Characteristic

AUDIO FILTERS

30

kHz Low-Pass Filter

3

dB Cutoff Frequency

80 kHz Low-Pass Filter

3

dB Cutoff Frequency

400

Hz High-pass Filter (Option

010

or

050)

3

dB Cutoff Frequency

CCITT

Weighting Filter (Option 011 or

051)

Deviation from Ideal Response(')

CCIR Weighting Filter (Option

012

or 052)

Deviation from Ideal Response(2)

C-Message Weighting Filter (Option

013

or

053)

Deviation from Ideal Response(3)

CCIR/ARM

Weighting Filter (Option

014

or

054)

Deviation from Ideal Response(4)

Performance

Limits

30

kHz

32

kHz

80 kHz

M

kHz

400

Hz

MO

Hz

A2

dB

il

dB

i0.2

dB

32

dB

zt3

dB

32

dB

fl

dB

f0.5

dB

fO.l

dB

f0.2

dB

i0.4

dB

il

dB

f2

dB

fO.1

dB

ztl dB

&l

dB

i0.5

dB

iO.l

dB

f0.2

dB

k0.4

dB

zt1 dB

i2

dB

Conditions

20

to

55O,

80%

relative humidity

50

to

300 Hz

300

Hz to

3

kHz

800

Hz

3

to

3.5

kHz

3.5

to

5

kHz

20

to

55O,

8O%

relative humidity

20

to

31.5

Hz

31.5

to

200

Hz

0.2

to

6.3

kHz

6.3

kHt

6.3

to

7.1

kHz

7.1

to

10

kHz

10

to

20

kHz

20

to

31.5

kHz

20

to

55O,

80%

relative humidity

1

kHz

60

Hz to

5

kHz

20

to

55O,

80%

relative humidity

31.5

to

200

Hz

200

Hz to

6.3

kHz

6.3

kHz

6.3

to

7.1

kHz

7.1

to

10

kHz

10 to

20

kHz

20

to

31.5

kHz

See the Internattonal Telegraph and Telephone Consulatlve Committee (CCITT), Fifth Plenary Assembly, 1972, Telephone Transmission

Quality, The International Telecommunication Union (1973), pp. 87-91. (CCITT Recommendation P53.)

21

See the International Radio Consultative Committee (CCIR), Recommendations and Reports

of

the CCIR, 1978,

Vol.

X,

pp.

162-163.

(CCIR recommendation 409-3.)

3,

See the Bell System Technical Reference 41009, May 1975.

'I

See Dolby Laboratories Inc., Engineering Field Bulletin

No.

19/4.

~

4-15

Performance Tests Model 8903E

PERFORMANCE TESTS

“A”

Weighting Filter (Option

015

or

055)

Deviation

from

Ideal Response15)

I

Characteristic

I

Performance Limits

I

Conditions

20

to

55’,

80%

relative humidity

20

Hz

to

10

kHz

10

to

20

kHz

fO.l

dB

1

kHz

f0.5

dB

fl

dB

~~

DESCRIPTION:

The output of the Distortion Analyzer is connected to the input. At various frequencies, the ac level of the

output is measured with the audio filters in and out. The ratio of the two levels is the frequency response of

the filter at that frequency.

EQUIPMENT:

Audio Synthesizer

.....................................

HP 3336C

Controller with HP-IB

............................

HP

85B

Opt

007

PROCEDURE:

NOTE

The

Distortion Analyzer’s HP-IB addrcss is assiimcd

to

he

728.

All

HP-IB commands

are given in

BASIC.

1.

Connect the HP-IB controller

to

the Distortion Analyzer. Key in and execute the following command:

OUTPUT

728;

“41

.OSP

LO”

to initialize the instrument and set the

80

kHz LOW PASS FILTER

off.

2. Set the Distortion Analyzer’s INPUT switch to ground. Connect the audio synthesizer to the Distortion

Analyzer’s INPUT. Press the LCL

key

then set LOG/LIN

to

LOG.

3.

Set the audio synthesizer’s level to

2V

into an open circuit and set its frequency as indicated below.

For

each setting, perform the following procedure:

a. Set

all

filters

OK

Set RATIO

off

b. Set RATIO on. Set in the filter

as

indicated below.

b.

Note the dB ratio. If it is not between -3.01 and -2.99 dB, increment

or

decrement the audio

synthesizer’s frequency slightly until the indicated level is correct. The displayed frequency should

be within the limits indicated.

4-16

Model

8903E

Performance Tests

PERFORMANCE

TESTS

initial

SOURCE

Frequency

Setting (Hz)

400'

30

000

80

000

High- Pass Frequency Limits (Hz)

or Low-Pass

400 Hz HP

360

440

30

kHz LP

28

000

32

000

80

kHz LP

76

000

84

000

Filter Minimum Actual Maximum

4.

Key in and execute the following command on the controller:

OUTPUT

728;

"48.1

SP"

to

enable up-ranging

of

the output gain. Press

LCL.

Set the audio synthesizer's frequency as indicated

below in the table appropriate

for

the installed weighting filter.

For

each setting, perform the following

procedure:

a. Set all filters

off.

Set RATIO

off.

b. Set RATIO

on.

Select the appropriate weighting filter.

The

displayed ratio should be within the limits

indicated.

Tahk

for

CCITT

Weighting Filter (Option

011

or

051)

Frequency

(Hz)

50

100

200

300

500

800

1000

2000

3000

3500

5000

Ratio Limits

(d

Minimum

-43.0

-65.0

-23.0

-11.6

-4.6

-0.2

0.0

-4.0

-6.6

-1

0.5

-39.0

Actual Maximum

-61

.o

-39.0

-19.0

-9.6

-2.6

+0.2

+2.0

-2.0

-4.6

-6.5

-33.0

4-17

Performance

Tests

Actual

PERFORMANCE TESTS

Maximum

Model

8903E

Table

for

CCIR

Weighting Filtcr (Option

012

or

052)

SOURCE

Frequency

IHzI

31.5

63

1

00

200

400

800

1

000

2

000

3 150

4

000

5

000

6 300

7 100

8

000

9

000

10

000

12

500

14

000

16

000

20

000

31

500

Ratio Limits

(dB)

Minimum

-30.9

-24.9

-20.8

-14.3

-8.3

-2.4

-0.5

+5.1

+8.5

+10.0

+11.2

+12.1

+11.8

+11.0

+9.7

+7.7

-1

.o

-6.3

-1

2.7

-23.2

44.7

-22.9

-1

8.8

-1

3.3

-7.3

-1.4

+0.5

+6.1

+9.5

+11.0

+12.2

+12.3

+12.2

+11.8

+10.5

+8.5

+1

.o

4.3

-1

0.7

-21.2

40.7

4-18

Model

8903E

Performance Tests

PERFORMANCE TESTS

Table

for

C-Message

Wtighting

Filter

(Option

013

or

053)

SOURCE

Frequency

(Hz)

60

100

200

300

400

500

600

700

800

900

1000

1200

1300

1500

1800

2000

2500

2800

3000

3300

3500

4000

4500

5000

Ratio Limits

(dB)

Minimum

-56.7

43.5

-26.0

-17.5

-1

2.4

-8.5

-5.7

-3.7

-2.5

-1.6

-0.1

-1.2

-1.5

-2.0

-2.3

-2.4

-2.9

-3.5

-6.2

-8.6

-15.5

-22.5

-29.5

Actual Maximum

-54.7

41.5

-24.0

-15.5

-1

0.4

-6.5

-3.7

-1.7

-0.5

+0.4

+0.1

+0.8

+0.5

0.0

-0.3

-0.4

-0.9

-1.5

4.2

-6.6

-13.5

-20.5

-27.5

4-19

Performance

Tests

Model

8903E

PERFORMANCE TESTS

Table

for

CCIR/ARM

Wtighting

Filter

(Option

014

or

054)

SOURCE

Frequency

(W

31.5

63

100

200

400

800

1

000

2

000

3

150

4

000

5

000

6 300

7 100

8

000

9

000

10

000

12 500

14

000

16

000

20

000

31 500

Ratio Limits

((

~ ~~

Minimum Actual

-36.5

-30.5

-26.4

-1

9.9

-13.9

-8.0

-6.1

-0.5

+2.9

+4.4

+5.6

+6.5

+6.2

+5.4

+4.1

+2.1

-6.6

-11.9

-1

8.3

-28.8

-50.3

Maxim

u

m

-34.5

-28.5

-24.4

-1

8.9

-12.9

-7.0

-5.1

+0.5

+3.9

+5.4

+6.6

+6.7

+6.6

+6.2

+4.9

+2.9

4.6

-9.9

-1

6.3

-26.8

-46.3

4-20

Model

8903E

Performance

Tests

PERFORMANCE

TESTS

SOURCE

Ratio Limits

(dB)

Frequency

20

25

31.5

40

50

63

80

100

125

160

200

250

31 5

400

500

630

800

1

000

1

250

1

600

2

000

2 500

3 150

4

000

5

000

6 300

8

000

10

000

12 500

16

000

(Hz)

I

Minimum

-51

.O

-45.2

-39.9

-35.1

-30.7

-26.7

-23.0

-1

9.6

-1

6.6

-1

3.9

-11.5

-9.1

-7.1

-5.3

-3.7

-2.4

-1.3

-0.1

+0.1

+0.5

+0.7

+0.8

+0.7

+0.5

0.0

-0.6

-1.6

-3.0

-5.3

-7.6

-1

0.3

20

000

Actual Maximum

-50.0

-44.2

-38.9

-34.1

-29.7

-25.7

-22.0

-1

8.6

-15.6

-12.9

-1

0.5

-8.1

-6.1

4.3

-2.7

-1.4

-0.3

+0.1

+1.1

+1.5

+1.7

+1.8

+1.7

+1.5

+1

.o

+0.4

-0.6

-2.0

-3.3

-5.6

-8.3

4-2

1

Performance Tests Model 8903E

PERFORMANCE

TESTS

4-12.

INPUT

IMPEDANCE PERFORMANCE

TEST

SPECIFICATION:

I

Characteristic

I

Performance Limits

I

Conditions

I

GENERAL

I

Input Impedance

I

1OOkn

*lo/o

I

Except

dc

level mode

1

DESCRIPTION:

An audio oscillator is connected

to

the Distortion Analyzer’s input, and a ratio reference is set. A known

impedance is then added in series with the input. The drop in level is a measure of the output

or

input

impedance. The test is repeated with the audio oscillator connected to the analyzer’s (ungrounded) outer

conductor.

NOTE

An

arrangcmcnt

of

!wo BNC-to-clip fead adapters (such as

HP

8120-1292)

and

a

makc-

lo-malt> BNC adapfer

(sirch

as

HP

1250-0216)

provide

a

convenient

way

to

insert

fhe

series resistor wifhoir

f

sf

ripping

cables

or

soldering leads.

EQUIPMENT:

Audio Oscillator..

.........................

HP

8903B or HP 3336C

Dual Banana

to

BNC Adapter

.........................

HP

101

10B

Dual Banana

to

BNC Adapter

.......................

HP 1251-2277

Resistor,

lOOkn

.....................................

HP

0698-7497

PROCEDURE:

1.

Switch the Distortion Analyzer

off,

then back on to initialize it. Set the INPUT switch to ground.

2.

Set the audio oscillator

to

3 Vrms at 100

Hz.

Connect the audio oscillator’s output to the Distortion

Analyzer’s

INPUT.

Press RATIO.

3.

Insert the

lOOkn

resistor in series with the center conductor of the audio oscillator’s output. The right

display should read between 49.90 and

50.40%

if the audio oscillator has

600n

output impedance, or

between 49.00 and

5

1.00%

if the audio oscillator has

50n

output impedance.

Display with 6000 Impedance: 49.90

Display with

50n

Impedance: 49.00 50.40°/o

5

1

.OO%

4.

On

the Distortion Analyzer, set the

INPUT

switch to FLOAT.

5.

Connect the equipment as shown

in

Figure 4-4. Note

how

the cable connects to the Distortion Analyzer’s

input through the two adapters. The adapters reverse the outer and inner conductor connections

to

the

cable.

4-22

Model

8903E

Performance Tests

PERFORMANCE

TESTS

8903E

DISTORTION ANALYZER

AUD

IO

OSCILLATOR

(NOTE THE

ORIENTATION

OF

THE QROUND

TERMINAL.)

1

QROUND INDICATOR

Figirrc

4-4.

Inpirf Irnpcdancc

Test

Setiip

6.

Press RATIO twice

to

establish a new reference.

7.

Insert the

lOOk0

resistor in series with the inner conductor of the audio oscillator’s output. The right

display should read between

49.90

and

50.40%

if the audio oscillator has

6000

output impedance

or

between

49.00

and 51.00% if the audio oscillator has

500

output

impedance.

Display with

6000

Impedance:

49.90

50.40%

5

1

.OO~/o

Display with

500

Impedance:

49.00

4-23

Performance Tests Model

8903E

PERFORMANCE

TESTS

4-13.

COMMON-MODE REJECTION RATIO PERFORMANCE TEST

SPECIFICATION:

I

Characteristic

I

Performance Limits

I

Conditions

I

GENERAL

Common Mode Rejection

Ratio

>60

dB

>50

dB

Differential

input

<2V;

20

to

1000

Hz

Differential

input

>2V; 20

to

1000

Hz

I

>40

dB

I

1

to

20

kHz

DESCRIPTION:

The output from an external audio oscillator is connected

to

both inner and outer conductors of the Distortion

Analyzer's input connector. The outer conductor is set to float. The ac level of the common-mode input is

then measured for two different input ranges.

EQUIPMENT:

Audio Oscillator.,

.........................

HP

8903B or

HP

3336C

Controller with HP-IB

............................

HP

85B

Opt

007

Dual Banana to BNC Adapter

.........................

HP

lOllOB

8903E

DISTORTION ANALYZER

I

i

I

1

OUTPUT

AUDIO

OSCILLATOR

AUDIO

CABLE

8903E INPUT SOURCE

BNC CONNECTOR OUTPUT

i&

STANDARD

BNC

MALE

GROUND

\

BRA

I

OED

TERMINAL

BIND

I

NG OUTER

POST CONDUCTOR

Figiirti

4-5.

Common-Mode Rqiection Ratio

Tcw

St>(

icp

PROCEDURE

NOTE

The

Distortion Analyzer's

HP-IB

addrtw is assitmcd

to

be

728.

AN

HP-113

commands

are given in

BASIC.

1.

Connect the HP-IB controller to the Distortion Analyzer. Key in and execute the following command:

OUTPUT

728;

"41

.OSP"

to initialize the instrument. Set the Distortion Analyzer's

INPUT

switch to

FLOAT.

4-24

Model

8903E

Performance Tests

Controller Oscillator

Commands Frequency

OUTPUT

728;

(Hz)

"1.12SP" 20

1

000

20 000

"1.1

SP" 20

000

1

000

20

PERFORMANCE TESTS

AC Level Limits

(mV)

Actual Maximum

1

.o

1

.o

10.0

3.2

2.

Set the audio oscillator to

1V

at

20

Hz.

The output impedance of the oscillator should be

600n.

3.

Connect the equipment as shown in Figure

4-5.

Note the use of the dual-banana-to-BNC adapters to tie

the inner and outer conductors of the input connector together.

NOTE

cables in place

of

the stripped

RF

coaxial cahltp.

dt>siripd, the connections can also

he

ma&

using

a

variely

of'

adapkrs and jiimper

4-25

Performance

Tests

Model

89033

Table

4-1.

Performance Test Record

(1

of

10)

Hewlett-Packard Company

Model

8903E

Audio Analyzer

Tested by:

Serial Number Date

-

Para.

No.

4-6.

Test Description

AC

LEVEL ACCURACY PERFORMANCE TEST

High-level, High-Input AC level Accuracy

__

Controller

Commands

OUTPUT

728;

(SP)

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

1.10

AC Calibrator

level

(Vrms)

300

150

100

70

45

30

15

10

7

4.5

Frequency

(Hz)

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

Minimum

98%

96%

98%

96%

98%

96%

98%

96%

98%

96%

98%

Results

Actual Maximum

102%

104%

102%

104%

102%

104%

1 02%

102%

1 02%

104%

102%

1 02%

102%

104%

102%

104%

4-26

Model 89033

Performance

Tests

Table

4-1.

Performance Test Record

(2

of

10)

Para.

No.

4-6.

(Cont’d)

Test Description

AC

LEVEL ACCURACY PERFORMANCE TEST (Cont‘d)

Hiah-Level, Hi!

Controller

Commands

OUTPUT

728;

(SP)

1.11

1.12

1.13

1.14

1.15

1.16

1.17

1.18

1.19

.Input AC Level Accuracy (Cont’d)

AC Calibrator

Level

(Vrms)

3.0

1.5

1

.o

0.7

0.45

0.30

0.15

0.10

0.07

0.007

Frequency

(Hz)

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

Minimum

98%

96%

98%

96%

98%

96%

98%

96%

98%

96%

98%

Results

Actual Maximum

102%

104%

1 04%

102%

1

02%

102%

104%

102%

1

02%

102%

104%

102%

104%

102%

104%

102%

4-27

Performance

Tests

Model

89033

Table

4-1.

Performance Test

Record

(3

of

10)

Para.

No.

4-6.

Cont'd.

Test Description

AC

LEVEL ACCURACY PERFORMANCE TEST ICont'dl

High-Leve

Controller

Commands

OUTPUT

728;

(SP)

1.6

1.7

1

.a

1.9

1.10

1.11

1.12

1.13

1.14

1.15

Low-Input

AC

Level Accuracy

AC Calibrator

Level

(Vrms)

30

15

10

7

4.5

3.0

1.5

1

.o

0.7

0.45

Frequency

100

000

20

000

2

000

20

2

000

20

000

100 000

100

000

20

000

2

000

20

2

000

20

000

100 000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

(Hz)

Minimum

96%

98%

96%

98%

96%

98%

96%

98%

96%

98%

96%

Results

Actual Maximum

104%

102%

104%

102%

104%

1

04%

102%

1

04%

104%

1

02%

102%

1

02%

102%

104%

102%

1

02%

102%

104%

4-28

Model

89033

Performance Tests

Table

4-1. Performance Test Record (4 of 10)

Test Description

AC LEVEL ACCURACY PERFORMANCE

TEST

(Cont'dl

High-level, low-Input AC Level Accuracy (Cont'd)

Controller

Commands

OUTPUT

728;

(SP)

1.16

1.17

1.18

1.19

AC Calibrator

level

(Vrms)

0.30

0.15

0.1

0

0.07

0.007

Frequency

(Hz)

100

000

20 000

2

000

20

2 000

20

000

100

000

100

000

20

000

2

000

20

2

000

20

000

100

000

100

000

20

000

2

000

20

Synthesizer

Frequency

(Hz)

Displayed

Reading

of

Step b

(O/O)

Low-level, low-lnp

20

2

000

20

000

100

000

AC level Accuracy

I

low-Level, High-Input AC Level Accuracy

100

000

20

000

2

000

20

Minimum

96%

98%

96%

98%

96%

98%

96%

Results

Actual Maximum

104%

102%

104%

102%

104%

102%

4-29

Performance

Tests

Model

89033

Table

4-1.

Performance

Test

Record

(5

of

10)

Test Description

I-b-7.I-

DC

LEVEL

ACCURACY

PERFORMANCE

TEST

High-Input DC-Level Accuracy

DC Standard Voltage

300 Vdc

30 Vdc

3 Vdc

0.4

Vdc

0.04

Vdc

I

4-8.

~~

Low-Input DC-Level Accuracy

DC Standard Voltage

0.04

Vdc

0.4

Vdc

3 Vdc

30 Vdc

300 Vdc

I

1

DISTORTION AND NOISE PERFORMANCE TEST

100

000

Audio Oscillator

Frequency

(Hz)

20

1

000

1

000

1

000

1

000

20

000

50

000

50

000

100

000

100

000

3.0

2.5

1.9

0.3

3.0

0.3

3.0

2.5

1.9

LOW

PASS

FILTER

80

kHz

80

kHz

80

kHz

80

kHz

80 kHz

80

kHz

Off

Results

Maximum

Minimum Actual

297.75 Vdc

29.775 Vdc

2.9775 Vdc

0.397 Vdc

0.037 Vdc

0.054 Vdc

0.594 Vdc

2.9775 Vdc

29.775 Vdc

297.75 Vdc

302.25 Vdc

30.225 Vdc

3.0225 Vdc

0.403 Vdc

0.043 Vdc

0.403 Vdc

3.0225 Vdc

30.225 Vdc

302.25 Vdc

0.01~/0

0.01

%

0.01%

0.01

Yo

0.01

Yo

0.01

Yo

0.03%

0.04%

4-30

Model

89033

Performance Tests

Second Oscillator

Frequency Atten

(Hz)

(dB)

Table

4-1.

Performance Test Record

(6

of

10)

Low-Distortion

Oscillator

Frequency

(Hz)

Para.

No.

4-9.

-

Test Description

50

4

000

4

000

4

000

4

000

4

000

4

000

4

000

4

000

6

000

6

000

8

000

8

000

10

000

10

000

40

000

40

000

Readings in step

3

~

10

80

10

20

30

40

50

60

70

80

10

80

10

80

25

2

000

2

000

2

000

2

000

2

000

2

000

2

000

2 000

2

000

2

000

2

000

2

000

2

000

2

000

20

000

20

000

Readings in step

4

200

000

200

000

300

000

300

000

10

60

10

100

000

100

000

100

000

100

000

Minimum

-1

1.4 dB

-81.0 dB

-1

1.4 dB

-21.0 dB

-31.0 dB

-41.0

dB

-51.0 dB

-61.0

dB

-71.0

dB

-81.0

dB

-81.0

dB

-1

1.4 dB

-11.4 dB

-81.0 dB

-1

1.4

dB

-1

1.4 dB

-81.0

dB

-12.4 dB

-62.0 dB

-12.4 dB

Results

Actual Maximum

-9.4

dB

-79.0 dB

-9.4 dB

-19.0 dB

-29.0

dB

-39.0

dB

-49.0

dB

-59.0

dB

-69.0 dB

-79.0

dB

-79.0

dB

-9.4

dB

-9.4

dB

-79.0

dB

-79.0

dB

-9.4

dB

-9.4

dB

-79.0

dB

-8.4 dB

-58.0

dB

-58.0

dB

-8.4 dB

4-31

Performance

Tests

Model

89033

Initial SOURCE

Frequency Setting

(Hz)

400'

30

000

80

000

'Option

010

or

050

Table

4-1.

Performance Test Record

(7

of

10)

Filter

400 Hz HP

30 kHz LP

80 kHz LP

Para.

No.

4-10.

4-11.

Test Description

FREQUENCY ACCURACY AND SENSITIVITY

PERFORMANCE TEST

MEASUREMENT

Mode

AC

LEVEL

DlSTN

DlSTN 99 900

AC

LEVEL 99 900

AC

LEVEL 150

00

AUDIO FILTERS PERFORMANCE TEST

SOURCE Frequency

(Hz)

CClTT Weighting Filter (Option

011

or

051)

50

100

200

300

500

800

1

000

2

000

3

000

3

500

5

000

CClR Weighting Filter (Option 012

or

052)

31.5

63

100

200

400

800

1000

2

000

3 150

Minimum

19.99

99 895

149 980

360 Hz

28

000

Hz

76

000

Hz

-65.0

dB

-43.0 dB

-23.0

dB

-1

1.6 dB

-4.6

dB

-0.2 dB

0.0

dB

-4.0 dB

-6.6

dB

-10.5 dB

-39.0 dB

-30.9 dB

-24.9 dB

-20.8

dB

-14.3

dB

-8.3

dB

-2.4

dB

-0.5

dB

+5.1

dB

+8.5

dB

Results

Actual Maximum

20.01

99 905

150 020

440 Hz

32

000

Hz

84

000

Hz

-61.0 dB

-39.0 dB

-19.0 dB

-9.6 dB

-2.6

dB

+0.2

dB

+2.0 dB

-2.0 dB

-4.6 dB

-6.5 dB

-33.0 dB

-28.9 dB

-22.9 dB

-18.8

dB

-13.3

dB

-7.3 dB

-1.4 dB

+0.5

dB

+6.1 dB

+9.5

dB

4-32

Model

89033

Performance

Tests

Table

4-1.

Performance Test Record

(8

of

10)

-

Para.

No.

-

4-11

Cont'd)

-

Test Description

AUDIO FILTERS PERFORMANCE TEST (Cont'd)

CClR Weighting Filter (Option

012

or

052)

(Cont'd)

4

000

5

000

6 300

7

100

8

000

9

000

10

000

12 500

14

000

16

000

20

000

31 500

C-Message Weighting Filter (Option 013

or

053)

60

100

200

300

400

500

600

700

800

900

1

000

1 200

1

300

1 500

1

800

2

000

2 500

2

800

3

000

3 300

3

500

4

000

4 500

5

000

CCIR/ARM Weighting Filter (Option 014

or

054)

31.5

63

100

200

400

800

1

000

Results

Maximum

Minimum Actual

+10.0 dB

+11.2 dB

+12.1 dB

+11.8 dB

+11.0 dB

+9.7 dB

+7.7 dB

-1.0 dB

-6.3 dB

-12.7 dB

-23.2 dB

-44.7 dB

-56.7 dB

-43.5 dB

-26.0 dB

-17.5 dB

-12.4 dB

-8.5 dB

-5.7 dB

-3.7 dB

-2.5 dB

-1.6 dB

-0.1 dB

-1.2 dB

-1.5 dB

-2.0 dB

-2.3 dB

-2.4 dB

-2.9 dB

-3.5 dB

-6.2 dB

-8.6

dB

-15.5 dB

-22.5 dB

-29.5 dB

-36.5 dB

-30.5 dB

-26.4 dB

-19.9 dB

-13.9 dB

-8.0 dB

-6.1 dB

+11

.O

dB

+12.2 dB

+12.3 dB

+12.2 dB

+11.8 dB

+10.5 dB

+8.5 dB

+1.0 dB

-4.3 dB

-10.7 dB

-21.2 dB

-40.7 dB

-54.7 dB

-41.5 dB

-24.0 dB

-15.5 dB

-10.4 dB

-6.5 dB

-3.7 dB

-1.7 dB

-0.5 dB

+0.4 dB

+0.1 dB

+0.8

dB

+0.5 dB

0.0

dB

-0.3 dB

-0.4 dB

-0.9 dB

-1.5 dB

-4.2 dB

-6.6 dB

-13.5 dB

-20.5 dB

-27.5 dB

-34.5 dB

-28.5 dB

-24.4 dB

-18.9 dB

-12.9 dB

-7.0 dB

-5.1 dB

I

4-33

Performance

Tests

Model

89033

Table

4-1.

Performance Test Record

(9

of

10)

Para.

No.

(Cont‘d)

4-1

1

Test Description

AUDIO

FILTERS

PERFORMANCE TEST (Cont’d)

SOURCE Frequency

(Hz)

(Cont’d)

CCIR/ARM Weighting Filter (Option 014

or

054) (Cont’d)

2

000

3 150

4

000

5

000

6 300

7 100

8 000

9

000

10

000

12 500

14 000

16 000

20 000

31 500

“A”

Weighting Filter (Option

015

or 055)

20

25

31.5

40

50

63

80

100

125

160

200

250

31

5

400

500

630

800

1

000

1 250

1

600

2 000

2 500

3 150

4

000

5

000

6 300

8

000

10

000

12

500

16 000

20

000

Results

Maximum

Minimum Actual

~~~

-0.5

dB

+2.9 dB

+4.4 dB

+5.6 dB

+6.5 dB

+6.2 dB

+5.4 dB

+4.1 dB

+2.1 dB

-6.6 dB

-11.9 dB

-18.3 dB

-28.8 dB

-50.3 dB

-51.0 dB

-45.2 dB

-39.9 dB

-35.1 dB

-30.7 dB

-26.7 dB

-23.0 dB

-19.6 dB

-16.6 dB

-13.9 dB

-11.5 dB

-9.1 dB

-7.1 dB

-5.3 dB

-3.7 dB

-2.4 dB

-1.3 dB

-0.1 dB

+0.1 dB

+0.5

dB

+0.7 dB

+0.8 dB

+0.7 dB

+0.5 dB

0.0

dB

-0.6 dB

-1.6 dB

-3.0 dB

-5.3 dB

-7.6 dB

-10.3 dB

+0.5

dB

+3.9 dB

+5.4 dB

+6.6 dB

+6.7 dB

+6.6 dB

+6.2 dB

C4.9 dB

+2.9 dB

-4.6 dB

-9.9 dB

-16.3 dB

-26.8 dB

-46.3 dB

-50.0 dB

-44.2 dB

-38.9 dB

-34.1 dB

-29.7 dB

-25.7 dB

-22.0 dB

-18.6 dB

-15.6 dB

-12.9 dB

-10.5 dB

-8.1 dB

-6.1 dB

-4.3 dB

-2.7 dB

-1.4 dB

-0.3 dB

+0.1 dB

+1.1 dB

+1.5 dB

+1.7 dB

+1.8 dB

+1.7 dB

t1.5 dB

+1.0 dB

+0.4 dB

-0.6 dB

-2.0 dB

-3.3 dB

-5.6 dB

-8.3 dB

4-34

Performance

Tests

Model

89033

4-12.

4-13.

Table

4-1.

Performance Test Record

(10

of

10)

I

INPUT IMPEDANCE

PERFORMANCE TEST

High

Input

49.00%

Low

Input

49

.OO%

COMMON-MODE REJECTION RATIO

PERFORMANCE TEST

\

I

Para.

No. Test Description

+

Minimum

Oscillator Frequency

(Hz)

Controller Commands

OUTPUT

728;

(SP)

1.12

1.1

20

1

000

20

000

20

000

1

000

20

Results

Actual Maximum

51

.OO%

51.00%

1

mV

1

mV

10.0

mV

10.0

mV

3.2 mV

4-35

Model

8903E

Adjustments

Section

5

ADJUSTMENTS

5-1.

INTRODUCTION

This section contains adjustments and checks that assure peak performance of the Distortion Analyzer. The

instrument should be readjusted after repair or failure

to

pass

a

performance test. Allow a

30

minute warm-up

prior

to

performing the adjustments. Removing the instrument

top

cover and the internal shield cover is the

only disassembly required for all adjustments.

To

determine which performance tests and adjustments

to

perform after a repair, refer

to

paragraph

5-5,

Post

-R

epa ir

Tes

f

s,

A

dji

rst

men

1s.

and Ch wks.

5-2.

SAFETY CONSIDERATIONS

This section contains information, cautions, and warnings which must be followed for your protection and

to

avoid damage

to

the equipment.

A

djiistments describt.d

in

this stciion arc pcvjhrmcd wifh power siipplicd

lo

fhc

insfnimcwt

and with proftcfivc c0vcv-s rcvnowd. Mainfcnancc shoirld

he

pcv-formcd only by stv-vicc

fraincd pcrsonncl who arc a warc

of

thc hazard involwd Cfor cxampk, jirc and dccfrical

shock). Whcw

maintenance

can be perjormtid withoir

f

powc’r applicd.

the

powcr

shoirld

he

rcmoved.

5-3.

EQUIPMENT REQUIRED

Most adjustment procedures contain a list of required test equipment. The test equipment is also identified by

callouts in the test setup diagrams, where included.

If

substitutions must be made for the specified test equipment, refer to Table

1-3

in Section

1

of this manual

for the minimum specifications. It is important

that

the test equipment meet the critical specifications listed in

the table if the Distortion Analyzer is

to

meet its performance requirements.

5-4.

FACTORY-SELECTED COMPONENTS

Factory-selected components are identified on the schematics and parts list by

an

asterisk

(*)

which follows

the reference designator. The normal value or range of the components is shown. The Manual Changes sup-

plement will provide updated information pertaining

to

the selected components. Table

5-

1

lists the reference

designator, the criteria used for selecting a particular value, the normal value range and the service sheet where

the component part is shown.

5-5.

POST-REPAIR TESTS, ADJUSTMENTS, AND CHECKS

Table

5-2

lists the performance tests, adjustments and checks needed

to

calibrate or verify calibration of

a

repaired assembly. The tests, adjustments and checks are classified by assembly repaired.

The table is also useful

as

a cross reference between performance tests and assemblies when the failure is

a

specification that is slightly

out

of

limits.

After all repairs, perform the

Basic

Fiinc-[ionul

Cheeks

(paragraph

3-

10)

and the

Inltv-nal R&rcnt.t> Freqircncy

A

djirslment

(paragraph

5-7).

The Basic Functional Checks utilize automatic tuning and measurements which

exercise nearly every circuit in the instrument

(except

the Remote Inteface Assembly).

5-

1

Adjustments Model

8903E

Reference

Designator

A2C4 and A2C89

A2C9 and A2C102

A4R143 and A4R144

5-6.

RELATED ADJUSTMENTS

Service Range

of

Basis

of

Sheet Values Selection

1

43 to 56 pF

1

6.2 to 7.5 pF

6

See Input Flatness Adjustment (paragraph 5-8).

See Voltmeter Adjustment (paragraph 5-13 or 14).

147 kR to infinity

The procedures

in

this

section can be done

in

any order, but it

is

advisable

to

check the time base reference

first.

Assembly Repaired Test, Adjustment, or Check

A1 Keyboard and Display Assembly Power-Up Checks

Service Special Functions (Use 60.0 SPCL, Key Scan, and

exercise all keys.)

A2 Input Amplifier Assembly AC Level Accuracy Performance Test

DC Level Accuracy Performance Test

Tuhk

5-

I.

Factory

Sdccltd

Components

Ref.

Para.

8-27*

8-23'

4-6

4-7

A3 Notch Filter Assembly

A4 Output Amplifier/Voltmeter

Assembly

A7 Latch Assembly

A8 Controller/Counter Assembly

A9 Remote Interface Assembly

A10 Remote Interface Connector

Assembly

A1

1

Series Regulator Socket

Assembly

A1

2

Connector/Filter Assembly

A13 Power Supply and Mother Board

Assembly

Common-Mode Rejection Ratio Performance Test 4-1 3

Input Flatness Adjustment 5-8

Common-Mode Rejection Adjustment

5-9

400 Hz High-Pass and Weighting Bandpass Filters Adjustment

Distortion and Noise Performance Test

Notch Filter Tune and Balance Adjustment

AC Level Accuracy Performance Test

5-1

1

4-8

5-1 2

4-6

4-7

4-8

4-9

DC Level Accuracy Performance Test

Distortion and SINAD Accuracy Performance Test

Distortion and Noise Performance Test

Voltmeter Adjustment 5-13 or 14

Basic Functional Checks 3-1

0

Frequency Accuracy and Sensitivity Performance Test 4-1

0

Power-Up Checks 8-27'

Basic Functional Checks 3-1

0

Frequency Accuracy and Sensitivity Performance Test 4-1

0

Internal Reference Frequency Adjustment 5-7

Power-Up Checks 8-27*

HP-IB Functional Checks 3-1

1

Power-Up Checks 8-27*

I

Basic Functional Checks 3-1

0

Power-Up Checks 8-27*

Distortion and Noise Performance Test

I

Audio Filters Performance Test

I

4-8

I

4-11

A14 Line Power Module

I

These paragraphs are found in the HP 89036

Service

Manual.

5-2

Model

8903E

r

0

O

E

VERTICAL

INPUT

ODUD

0

won

-

0

00

Adjustments

ADJUSTMENTS

EXTERNAL

TR

I

WER

OUTPUT

FREQUENCY

STANDARD

5-7.

INTERNAL REFERENCE FREQUENCY ADJUSTMENT

Reference:

Service Sheet

15.

Description:

An

oscilloscope, triggered by an external reference, is used to monitor the internal reference frequency while

it

is

adjusted.

Equipment:

Frequency Standard

..............................

House Standard

Oscilloscope

..........................................

HP

1740A

Procedure:

1. Allow the equipment to warm up for

15

minutes.

2.

Connect the equipment

as

shown in Figure

5-1.

(The figure shows the setup for house-standard

frequencies of

2

MHz or lower.

If

the frequency

of

the frequency standard is

5

or

10

MHz,

reverse

the vertical input and external trigger connections

on

the oscilloscope.)

3.

Set the oscilloscope’s vertical sensitivity to view the Distortion Analyzer’s time base reference

(or

the frequency standard output). Set the horizontal scale for

0.1

ps

per division. Set the oscilloscope

to

trigger externally.

4.

Adjust

A8C27

for

a waveform movement

of

10 divisions per second

or

less. A totally non-metallic

adjustment

tool

is recommended.

NOTE

A

movemtwf

oJ

the wavcfbrm

lo

[he

right (or

lty?

if

tht.

oscilloscope

conntxYion.s

arc

rtwrscu‘)

a[

a

rule

of’

one

division pcr second mt~ans [hat [he

Dislorfion

A

nalyzcr’s

lime

ha.se.frcqiiency is low

hy

0.

I

ppm.

5-3

Adjustments

OUTPUT

-

INPUT

UDUU

0.

Bo

0

wan-0

Model 8903E

ADJUSTMENTS

AC

CAL

I

BRAT

I

OR

5-8.

INPUT FLATNESS ADJUSTMENT

Reference:

Service Sheet

1.

Description:

An ac calibrator is connected to the input of the Distortion Analyzer. The Distortion Analyzer is set

to

measure

ac level. The frequency of the calibrator is varied between

1,

40,

and

100

kHz and the flatness adjusted is for

a constant level at all three frequencies. The procedure is repeated for two other input ranges. The entire

procedure is run with the outer conductor of the input connector grounded, then with the inner conductor

grounded and the signal applied to the (ungrounded) outer conductor.

Voltages up

to

60

Vrms will

he

applied

to

the Distortion Analyzer's inpiit

connector

and

will

be

prtwnt

on

thc assembly being adjrislcd. Do

not

extend tht. assembly or probe its

circiiilry whcn high

volfagc

is applied to tho inpiit.

Equipment:

AC Calibrator..

...........

HP 745A

or

Datron 4200

or

Fluke

5200A

Dual Banana to BNC Adapter

.........................

HP 101 10B

Dual Banana to BNC Adapter

.......................

HP 1251-2277

Figlire

5-2.

High-Input Flatntw Adjirsrmenl Test Set iip

Procedure:

High-Input Flatness Adjustment

1. Set the ac calibrator to

1

kHz

at

4

Vrms.

2.

Connect the equipment as shown

in

Figure

5-2.

3.

Switch the Distortion Analyzer

off,

then back on to initialize it. Set the INPUT switch to ground.

Set LP FILTER

off.

4. The right display of the Distortion Analyzer should read between

3.9

and 4.1V. Check that the input

is

on range 10 by pressing

S

(Shift) NOTCH TUNE

S

(Shift) NOTCH TUNE. The first two digits of

the left display should be 10. Press AC LEVEL. Press RATIO.

5.

Set the ac calibrator frequency to

40

kHz. Adjust A2C3

(HIGH

12 DB) for a reading

on

the right

display between 99.70 and 100.3Yo.

5-4

Model 8903E Adjustments

ADJUSTMENTS

6.

Set the ac calibrator frequency

to

100

kHz.

Adjust A2C3 for a reading between 99.50 and

100.5%.

Repeat steps

5

and

6

as

often

as

needed until the flatness at

40

kHz

and

100

kHz

is

within the limits

given.

NOTE

If

fhe Jla(ners cannof

hc

adjii.yft>d

.so

fhuf

fhs

40

kHz

and

100

kHt

wadings art’ hofh

within fhc givcw limits, chungc A2C4 as

jofbrlows:

IJ’fhc

100

kHz

wading is higher fhan

af 40

kHz,

dwrt>asr A2C4 by approximately

10%.

ljfhe 40

kHz

reading is highcr fhan

that af

100

kHt,

incwasc> A2C4 hy approximafdy

10%.

7.

On the Distortion Analyzer, press RATIO to turn it

OK

8.

Set the ac calibrator frequency to

1

kHz

and level to 15 Vrms.

9.

The right display of the Distortion Analyzer should read between

14.7

and

15.3V.

Check that the

input

is

on range

7

by pressing

S

(Shift) NOTCH TUNE

S

(Shift) NOTCH TUNE. The first digit of

the left display should be

7.

Press

AC

LEVEL.

Press RATIO.

10. Set the ac calibrator frequency to

40 kHz.

Adjust A2CIO

(HIGH

24

DB) for a reading on the right

display between

99.70

and 100.3%.

11. Set the ac calibrator frequency to

100

kHz.

Adjust A2C10 for a reading between

99.50

and

100.5%.

Repeat steps 10 and 11 as often as needed until the flatness at

40

kHz

and

100

kHz

is within the

limits given.

NOTE

Uthe jlatncss cannot

hc

adjiisted

.so

that the 40

kHz

and

100

kHz

reading.% arc both

within

thc

givcn limifs, changc A2C9 as./i~llows: IJ’fhc

100

kHz

reading

is

highcv- rhan

af 40

kHz,

dt.c.reast> A2C9 by approximuldy

1090.

Iffhe

40

kHz

wading is higher rhan

that at

100

kHz,

incrcase A2C9 by approximafdy

10%.

12. On the Distortion Analyzer, press RATIO to turn it

off,

13. Set the ac calibrator frequency

to

1

kHz

and level to

60

Vrms.

14.

The right display of the Distortion Analyzer should read between

58.8

and

61.2V.

Check that the

input

is

on range

4

by pressing

S

(Shift) NOTCH TUNE

S

(Shift) NOTCH TUNE. The first digit of

the left display should be

4.

Press AC LEVEL. Press RATIO.

15. Set the ac calibrator frequency to

40

kHz.

Adjust A2C109

(HIGH 40

DB)

for a reading

on

the right

display between 99.70 and 100.3°/o.

16.

Set the ac calibrator frequency

to

100 kHz. Adjust A2C109 for a reading between 99.50 and

100.5%.

Repeat steps

15

and

16

as often

as

needed until the flatness at

40 kHz

and

100

kHz

is

within the

limits given.

5-5

Adjustments Model 8903E

ADJUSTMENTS

Low-Input Flatness Adjustment

17. Set the ac calibrator to

1

kHz at 4 Vrms.

18.

On the Distortion Analyzer, set the INPUT switch

to

FLOAT.

19. Connect the equipment as shown

in

Figure 5-3. Note how the cable connects

to

the Distortion

Analyzer's input through the two adapters. The adapters reverse the outer and inner conductor

connections

to

the cable.

8903E

DISTORTION

ANALYZER

Bo

(NOTE THE

ORIENTATION

OF

THE QROUND

TERMINAL.)

.

QROUND INDICATOR

Figitre

5-3.

Low-Input Flalnm Adjitstment

Te..rt

Setirp

20. Switch the Distortion Analyzer

off,

then back on

to

initialize it. Set LP FILTER

off.

21. The right display of the Distortion Analyzer should read between 3.9 and 4.1V. Check that the input

is on range

10

by pressing

S

(Shift)

NOTCH TUNE

S

(Shift) NOTCH TUNE. The

first

two digits of

the left display should be

10.

Press AC

LEVEL.

Press RATIO.

22. Set the ac calibrator frequency

to

40

kHz. Adjust A2C90 (LOW 12 DB) for a reading on the right

display between 99.70 and

100.3%.

23. Set the ac calibrator frequency to

100

kHz. Adjust A2C90 for a reading between 99.50 and 1O0So/o.

Repeat steps 22 and 23 as often as needed until the flatness at 40 kHz and

100

kHz is within the

limits

given.

NOTE

If'the.flatness cannot he adjirsted

.so

that thc

40

kHz and

100

kHt

readings arc both

within Ihe given limits, change AZCH9

as

Jollow.~:

Ijthe 100

kHz

reading is higher than

at

40

kHz, det.rt.ase A2C89

hy

approximaldy

10%.

Il'thc

40

kHz reading

is

higher lhan

that

at

100

kHz,

increase AZC89 by approximately

IOYO.

24.

On

the Distortion Analyzer, press RATIO to turn

it

off.

25. Set the ac calibrator frequency

to

1

kHz and level

to

15

Vrms.

26. The right display of the Distortion Analyzer should read between 14.7 and 15.3V. Check that the

input is on range

7

by pressing

S

(Shift) NOTCH TUNE

S

(Shift) NOTCH TUNE. The first digit of

the left display should

be

7.

Press AC LEVEL. Press RATIO.

27. Set the ac calibrator frequency to

40

kHz. Adjust A2C110

(HIGH

24

DB)

for

a reading on the right

display between 99.70 and

100.3%.

5-6

Model

8903E

Adjustments

ADJUSTMENTS

28.

Set the ac calibrator frequency to 100 kHz. Adjust

A2C110

for a reading between

99.50

and

100.5%.

Repeat steps

27

and

28

as oflen

as

needed until the flatness at

40

kHz and

100

kHz is within the

limits given.

NOTE

If

the flatness

cannot

he

adjirstrd

so

that

the

40

kHz

and

100

kHz

readings are both

within the givcn limirs, changc A2C102 as follows:

If

the

100

kHz

reading is highcr than

at

40

kHz,

decrease A2Cl02 by approximately

10%.

Ifthc

40

kHz

reading is highcr than

that at

IO0

kHz,

increase

A

2CI

02

by approximattly

1

OOb.

29.

On the Distortion Analyzer, press RATIO to turn it

off.

30.

Set the ac calibrator frequency

to

1

kHz and level to

60

Vrms.

31.

The right display of the Distortion Analyzer should read between

58.8

and

61.2V.

Check that the

input is

on

range

4

by pressing

S

(Shift)

NOTCH TUNE

S

(Shift) NOTCH TUNE. The first digit

of

the left display should be

4.

Press AC

LEVEL.

Press

RATIO.

32.

Set the ac calibrator frequency

to

40

kHz. Adjust A2C110 (HIGH

40

DB) for a reading on the right

display between

99.70

and

100.3%.

33.

Set the ac calibrator frequency to

100

kHz. Adjust A2CI

10

for a reading between

99.50

and

100.5%.

Repeat steps

32

and

33

as often as needed until the flatness at

40

kHz and

100

kHz

is

within the

limits given.

34.

Perform the

A

C

Levd A ccirracy Pc.rfbrmanc.c. TtW

(paragraph

4-6).

5-7

Adjustments Model

8903E

ADJUSTMENTS

5-9.

COMMON-MODE REJECTION ADJUSTMENT

Reference:

Service Sheet

1.

Description:

An audio oscillator, set to

1

Vrms at

1

kHz, is connected to both the high and

low

(that is, the inner and outer

conductor) inputs

of

the Distortion Analyzer.

The

low

input.

is

set to float.

The

common-mode, ac level

is

then

adjusted

for

Equipment:

Procedure:

minimurn response.

Audio Oscillator..

.........................

HP

8903B

or

HP

3336C

Dual Banana to

BNC

Adapter

.........................

HP

101

10B

8903E

DISTORTION ANALYZER

OUTPUT

AUDIO

Bo

OSCILLATOR

8903E

INPUT

BNC CONNECTOR

&

STANDARD

BNC

MALE

GROUND

\

TERUI NAL BRAIDED

BINDING OUTER

POST CONDUCTOR

Fig1

I

re

5-4.

Common -Mode Rcjt’c*lion

A

dji

1sl

m cnl Tti.TI StY

I

ip

1. Switch the Distortion Analyzer

off,

then back on to initialize it. Set the Distortion Analyzer’s INPUT

switch to

FLOAT.

2.

Set the audio oscillator to

1V

at

1

kHz.

The output impedance

of

the oscillator should be

GOOR.

3.

Connect the equipment as shown in Figure

5-4.

Note how the cable center conductor and shield

are connected to the Distortion Analyzer INPUT connector and ground terminal.

NOTE

4.

Adjust

A2R43 (CM)

for the minimum level on the right display, but less than

0.2

mV

5.

Perform the

Common-Modc Rujcx*lion

Ratio

PcJrformancc

Tcsl

(paragraph

4-13).

5-8

Model 8903E Adjustments

ADJUSTMENTS

5-10.

INPUT

DC

OFFSET

ADJUSTMENT

Reference:

Service Sheet

1.

Description:

With the Distortion Analyzer set

to

measure dc level and the input grounded, the dc

offset

is

adjusted

for

a

display

of

OV.

Equipment:

Feedthrough Termination,

6000

.

. . . . . .

.

. .

. . .

.

HP 11095A

Procedure:

1.

Switch the Distortion Analyzer

off,

then back on to initialize it.

Set

the INPUT switch

to

ground.

Set MEASUREMENT

to

DC

LEVEL.

2.

Connect the

600a

feedthrough

(or

a

short

circuit

or

a

50fl

load)

to

the

INPUT.

3.

Adjust A2R44 (OFFSET)

for

a

steady reading

of

-0.OOV

on the right display.

5-9

Adjustments Model 8903E

ADJUSTMENTS

5-1

1.

400

HZ HIGH-PASS AND WEIGHTING BANDPASS FILTERS ADJUSTMENT

Reference:

Service Sheet 2, 2A, and 2B.

Description:

An audio oscillator is connected

to

the input

of

the Distortion Analyzer. The oscillator

is

set

to

a specified

frequency and a level reference

is

set. The filter

to

be

adjusted

is

then inserted and its gain is adjusted for

a

level equal to the reference.

Equipment:

Audio Oscillator..

. . . .

.

. . . . .

.

. . .

. .

. . . . . . .

HP 8903B or HP 3336C

Procedure:

NOTE

In

the

following

procedirrcs,

the

lefl-most

filter circiiil board is designated

A2A

I

and

the

righl-most

board

A2A2.

Thc

board locafion

corresponds

lo option

series

010

and

050

resptct

i

vely.

1. Switch the Distortion Analyzer

off,

then back on to initialize it. Set the INPUT switch

to

ground.

2. Set the audio oscillator amplitude

to

1

Vrms and connect its output to the Distortion Analyzer’s

INPUT.

3. Perform the following steps for each filter installed.

400

Hz High-Pass Filter

(Option

010

or

050)

a. Set the weighting filter

off,

if

on.

Set RATIO

off.

Set

the

audio oscillator’s frequency

to

2

kHz.

Set RAT10

on.

b. Press HIGH PASS 400

Hz.

Adjust A2AlR6

or

A2A2R6 (400 HZ) for a reading between

99.60 and 99.80% on the right display.

c.

Set the audio oscillator’s frequency

to

1

kHz. The right display should read between 99.00

and

101.0%.

CCITT Weighting Filter (Option

011

or

051)

a. Set

HIGH

PASS 400 Hz

or

weighting filter

off

if on. Set the audio oscillator’s frequency

to 800

Hz.

Set RATIO

off.

Set RATIO on.

b. Press CCITT WEIGHTING. Adjust A2AlR4 or A2A2R4 (CCITT) for

a

steady reading

of

100.0%

on

the right display.

CCIR Weighting Filter (Option

012

or

052)

a. Set

HIGH

PASS

400

Hz

or

weighting filter off

if

on. Set the audio oscillator’s frequency

to 6300

Hz.

Set RATIO

off.

Set

RATIO

on.

b. Press CCIR WEIGHTING. Adjust A2AlR7

or

A2A2R7 (CCIR) for a steady reading

of

407.4Oh

(

12.20 dB)

on

the

right

displny.

5-10

Model

8903E

Adjustments

ADJUSTMENTS

C-Message Weighting Filter (Option 013 or

053)

a. Set

HIGH

PASS

400

Hz

or

weighting filter

off

if on. Set the audio oscillator's frequency

to

1

kHz.

Set

RATIO

off.

Set

RATIO

on.

b.

Press

C-M

ESSAGE

WEIGHTING.

Adjust

A2A

1

R6

or

A2A2R6 (CMSG)

for a steady read-

ing of

100.0%

on the right display.

CCIR/ARM Weighting Filter (Option 014

or

054)

a. Set

HIGH

PASS

400

Hz

or

weighting filter

off

if on. Set the audio oscillator's frequency

to

6300 Hz.

Set

RATIO

off.

Set

RATIO

on.

b.

Press

CCIR/ARM WEIGHTING.

Adjust

A2AlR7

or

A2A2R7 (CCIR)

for a steady reading

of

213.8% (6.6

dB) on the right display.

"A"

Weighting Filter (Option

015

or

055)

a. Set

HIGH

PASS

400

Hz

or

weighting filter

off

if on. Set the audio oscillator's frequency

to

1

kHz.

Set

RATIO

off.

Set

RATIO

on.

b.

Press

"A" WEIGHTING.

Adjust

A2AlR3

or

A2A2R3 (A-WTD)

for a steady reading

of

100.Oo/o

on the right display.

4.

Perform the

Audio

Filkw

Perjorrnance

Tcsr

(paragraph

4-1

1).

5-1

1

Adjustments Model

8903E

ADJUSTMENTS

5-12.

NOTCH

FILTER

TUNE AND BALANCE ADJUSTMENT

Reference:

Service Sheet

4.

Description:

The Distortion Analyzer is set to measure the distortion from a clean audio oscillator. The output from the

notch filter is observed on an oscilloscope while the tuning and balance are adjusted for a minimum. The

measured distortion is also monitored on the amplitude display.

Equipment:

Audio Oscillator..

..........................

HP

8903B

or

HP

339A

Oscilloscope

..........................................

HP

1740A

8903E

DISTORTION

ANALYZER

OSCILLOSCOPE

EXTERNAL INPUT

TRIQGER

YON

I

TOR

iaiaC.0

e

0

B

o

E%O

-

0

rn

00

1

OUTPUT

I

Figlire

5-5.

Nofch

Fikr

Tune

and

Balancv

A

djitsfmenf

Test

Setup

Procedure:

1.

Switch the Distortion Analyzer

off,

then back on

to

initialize

it.

Set the INPUT switch to FLOAT.

Set MEASUREMENT to DISTN. Set

LOG

LIN to

LOG.

2.

Set the audio oscillator to

2.8V

at

1

kHz.

Connect the equipment as shown in Figure

5-5.

3.

Set the oscilloscope to view the ac signal at the MONITOR output. Set the oscilloscope’s trigger to

external.

4.

Adjust A3R62 (TUNE OFFSET) and A3R63 (BAL OFFSET)

for

minimum signal and noise on the

oscilloscope display.

5.

Observe the right display of the Distortion Analyzer. It should read

-90

dB or less. Readjust the two

adjustments to minimize the reading on the display which must be

-90

dB

or

less.

NOTE

If

thc wading

of’step

5

cannot

hc

hroiight within limit, it

may

btl

that thc

soiirctj

has

exccssivc

distortion.

5-12

Model 8903E Adjustments

A4TP1

(STEP

3)

(Dc

OUT)

-

INPUT

owma-0

no

1

ODD0

lm,

ADJUSTMENTS

INPUT

DIG

I

TAL

VOLTMETER

,

5-13.

VOLTMETER ADJUSTMENT (USING AN

HP-IB

CONTROLLER)

Reference:

Service Sheets

6

and

7.

Description:

The Distortion Analyzer is set to measure the ac level from an audio oscillator. The internal ac-to-dc converter

(as yet uncalibrated) produces a dc voltage that is read by the internal dc voltmeter and monitored by an

external dc voltmeter. The sensitivity of the internal dc voltmeter

is

adjusted

so

that the amplitude display

of

the Distortion Analyzer agrees with the level measured by the external dc voltmeter.

The ac level from the audio oscillator is then monitored by an external ac voltmeter. The ac-to-dc converter is

adjusted

so

that the amplitude display

of

the Distortion Analyzer agrees with the level measured by the external

ac voltmeter at two different levels. Since there are two ac-to-dc converters, one true-rms responding and one

average responding, two separate adjustments are made.

NOTE

If

an

HP-IB conlroller

is

no1

avuiluhk,

iisc

[he

nexl

udjirslmcnl procediire,

Voltmeter

Adjustment (Not Requiring an HP-IB Controller).

Equipment:

Audio Oscillator..

..........................

HP 89038 or HP 339A

Controller with HP-IB

............................

HP

85B

Opt

007

Digital Voltmeter..

....................................

HP

3455A

8903E

DISTORTION ANALYZER

OUTPUT

AUD

IO

I

-

TEE

OSCILLATOR

Figirrc

5-6.

Vollmcler

A

djirblmzn

1

Tcsl

Sclirp

Procedure:

NOTE

Thc

Distortion

A

nalyzrr's HP-IB addrcss

is a.wrmc.a'

lo

hc>

728.

AN

HP-IB commands

arc>

given

in

BA

SIC.

1.

Connect the HP-IB controller to the Distortion Analyzer. Key in and execute the following com-

mands:

OUTPUT

728;

"41 .OSP

1.1

1

SP

3.1

SP"

OUTPUT

728;

"49.3SP"

Adjustments Model 8903E

ADJUSTMENTS

to

initialize the instrument, set the input range to 3V, set the post-notch amplifier gain to

0

dB, and read

the output rms detector voltage directly.

NOTE

The above commands shoirld

not

he concatcnated.

A

short waiting period hctwetw

them

is

needed.

If

thc

HP-IB

commands are

to

be

piit

into

a program, insert a

200

ms

wait

betwcvn /he two oirtpirt statements.

2. Set the Distortion Analyzer’s INPUT switch

to

ground.

3.

4.

5.

6.

7.

8.

9.

Set the audio oscillator

to

3V

at

1

kHz.

Connect the equipment as shown in Figure

5-6.

Connect

the voltmeter

to

A4TP1 (DC OUT).

Set

the voltmeter

to

read dc volts. Adjust A4R125 (DC CAL) for a reading on the right display of the

Distortion Analyzer that is the same as the reading on the voltmeter (within

d~0.5

mV). (See Service

Sheet

7.)

Connect the voltmeter to the INPUT of the Distortion Analyzer as shown in Figure

5-6.

Set the

voltmeter to read ac volts. On the Distortion Analyzer, press the LCL key, then set the MEASURE-

MENT mode

to

AC LEVEL.

Adjust A4R91 (RMS SCALE) for a reading on the right display of the of the Distortion Analyzer

that is the same as the reading on the ac voltmeter (within

&I

mV). (See Service Sheet

6,)

Set the audio oscillator level

to

150

mV. On the Distortion Analyzer adjust A4R85 (RMS OFFSET)

for a reading on the right display that

is

the same as the ac reading on the ac voltmeter (within

k0.5

mV). (See Service Sheet

6.)

If A4R85 does not have sufficient range, add

or

alter A4R143 or A4R144

as follows:

a. Unsolder A4R143 or A4R144, if present.

b.

With a

dc

voltmeter, measure the voltage at the junction of A4R72 and A4C46.

c.

If the voltage (ignoring polarity) is greater than

2

mV, compute R= lSOO/V, where V is the

voltage measured (in volts).

d.

Select a resistor which has a standard value resistance nearest

R.

If the measured voltage is

negative, solder the new resistor in the location for A4R143; if positive, replace A4R144.

e.

After a five-minute warm up, measure the voltage again which should be between

-2

and

+2

mVdc.

f. Repeat the adjustment of A4R85.

Set the audio oscillator’s level to 3V. Repeat steps

6

through 8 until the right display of the Distortion

Analyzer and the ac voltmeter readings are the same within the limits stated in steps

6

and

7

for both

3V and 150 mV.

On the Distortion Analyzer, press AVG to select the average-responding detector. Set the audio

oscillator’s level

to

3V.

5-14

Model

8903E

Adjustments

ADJUSTMENTS

10.

Adjust A4R93 (AVG

SCALE)

for

a reading on the right display

of

the Distortion Analyzer that is the

same as the reading on the ac voltmeter (within

zk

1

mV).

(See Service Sheet

6.)

11.

Set

the audio oscillator’s level

to

150

mV. On the Distortion Analyzer, adjust

A4R149

(AVG

OFFSET)

for

a reading on the right display that is the same as the reading on the ac voltmeter (within

*OS

mV).

(See Service Sheet

6.)

12.

Set AMPTD

to

3V. Repeat steps

10

through

12

until the right display

of

the Distortion Analyzer and

the ac voltmeter are the same within the limits stated in steps

10

and

11

for

b0t.h

3V

and

150

mV.

Adjustments Model 8903E

ADJUSTMENTS

5-1

4.

VOLTMETER ADJUSTMENT (NOT REQUIRING

AN

HP-IB

CONTROLLER)

Reference:

Service Sheets

6

and

7.

Description:

The Distortion Analyzer is set

to

measure the ac level

of

an external audio oscillator. The ac signal at the

oscillator's output is monitored by an external ac voltmeter. The ac-to-dc converter is adjusted

so

that its

dc output agrees with the level measured by the external ac voltmeter at two different levels. Both the

rms-

responding and average-responding ac-to-dc converters are calibrated. The internal ac-to-dc converter produces

a

dc

voltage that is read by the internal dc voltmeter and monitored by an external dc voltmeter. The sensitivity

of

the internal dc voltmeter is adjusted

so

that the amplitude display

of

the Distortion Analyzer agrees with the

level measured by the external dc voltmeter.

Equipment:

Procedure:

1.

Switch

NOTE

If'

an

HP-IB

controllcr is availahkc, this adjirs~mc~n~ can

bc

simpl!fic~d using

adj

I

r

s

1

mm

1

proced

I

ire,

Voll

m etcr A dji

t

slmen

I

(Using an

HP-IB

Coni

roller).

Audio Oscillator..

..........................

HP

8903B

or

HP 339A

Digital Voltmeter

(A)

..................................

HP 3468A

Digital Voltmeter

(B)

..................................

HP

3455A

NOTE

Voltmeter

A

is optional.

If

one

volrrnrler i.r iwd,

conn(w

it, as rt.qitirt.d,

thc prcvio1r.s

hrlwtvn the

poin1.s indiicarcd in (hc proc'c~/iirc~ and Figiirc

5-7.

SCI

il

lo

rcad

dc

volts whcw connccled

to

A4TPI and ac

volls

whcw

conncwcd

lo

the

ICY

at thc Dislorlion Analyzc.r's INPUT.

Record Ihc. rcadings jor comparison

in

s~rhscyiicv~l

~1cp.s.

the Distortion Analyzer

off,

then back on to initialize

it.

Set the INPUT switch to ground.

2.

Connect the equipment as shown in Figtire

5-7.

Connect voltmeter

B

to A4TPl (DC

OUT)

and set

it

to

measure

dc

volts. Set voltmeter

A

to

measwe ac volts. Set the audio oscillator

to

2.5

Vrms at

1

kHz.

A4TPl

IDC

OUT)

.

I

INPUT

D

IQl

TAL

1

VOLTMETER

A

8903E

DISTORTION ANALYZER

1

I

AUD

IO

OSCILLATOR VOLTMETER

B

5-

16

Model 8903E Adjustments

ADJUSTMENTS

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

Press

S

(Shift) NOTCH TUNE

S

(Shift) NOTCH TUNE. The left display should read 11214.

NOTE

Do

nof

press

any addifional kcys

rinfil

skp

8.

This

display

musf

he

prcwnf

fhrurigh

Jftp

7

in

order

lo

prevenl instrirmcnl ranging.

Set the audio oscillator

to

3

Vrms at

1

kHz.

Adjust A4R91 (RMS SCALE)

for

a reading

on

voltmeter

B

that is the same as the reading

on

voltmeter

A (within

fl

mV). (See Service Sheet

6.)

Set the audio oscillator amplitude

to

150

mV. Adjust A4R85 (RMS OFFSET) for a reading on

voltmeter

B

that is the same as the reading on voltmeter A (within

k0.5

mV). (See Service Sheet

6.)

If A4R85 does not have sufficient range, add

or

alter A4R143

or

A4R144 as follows:

a.

b.

C.

d.

e.

f.

Unsolder A4R143

or

A4R144 if present.

With a dc voltmeter, measure the voltage at the junction of A4R72 and A4C46.

If the voltage (ignoring polarity) is greater than 2 mV, compute

R=

1500/V, where V is the

voltage measured (in volts).

Select

a

resistor which has

a

standard value resistance nearest

R.

If the measured voltage is

negative, solder the new resistor in the location for A4R143; if positive, replace A4R144.

After a five-minute warm-up, measure the voltage again which should be between -2 and

+2 rnV dc.

Repeat the adjustment of A4R85.

Set

the audio oscillator amplitude

to

3V.

Repeat steps

5

through 7 until the readings tor voltmeter

A and voltmeter

B

agree within the limits stated for both

3V

and

150

mV.

On

the Distortion Analyzer, select the averaging detector. Set the audio oscillator amplitude

to

2.5V

and key in

S

(Shift) NOTCH TUNE

S

(Shift) NOTCH TUNE. The left display should read 11214.

NOTE

Do

not

prtx

any

addirionul kcys rrrilil slt’p

12.

This display

mial

hci

prcwnl through

sfcp

11.

Set the audio oscillator amplitude to 3V. Adjust A4R93 (AVG SCALE) for

a

reading on voltmeter

B

that is the same as the reading on voltmeter A (within fl mV). (See Service Sheet

6.)

Set the audio oscillator

to

150 mV. Adjust A4R149 (AVG

OFFSET)

for a reading on voltmeter

B

that is the same as the reading

on

voltmeter A within

f0.5

mV. (See Service Sheet

6.)

Set

the audio oscillator amplitude

to

3V.

Repeat steps

9

and 10 until the readings for voltmeter A

and voltmeter

B

agree within the limits stated

for

both 3V and 150 mV.

Press AC LEVEL. Set the audio oscillator to

3V

at

1

kHz.

Leave the Distortion Analyzer’s detector

in average.

Adjust AJR125 (DC CAL) until the right display of the Distortion Analyzer and voltmeter

B

agree

(within

k0.5

mV).

5-17

A_8903E A 8903E

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