HP 8903B Operation Manual

..

,

.':tis:.

.**e..

:

.

:

.

Agilent Technologies. Inc 24001

E

Mission

Liberty

take, WA

99019

.

Ag

i I en

t

Technologies

Innovating

June

Dear Customer,

As semiconductor products, health care solutions, and chemical analysis became a new company, Agilent Technologies. Now, many of your Hewlett-Packard products and services are in the care

Agilent Technologies.

the

8,2000

of

November

HP

Way

1,1999,

four of Hewlett-Packard's businesses, test and measurement,

www

agilent

corn

of

At Agilent Technologies, we are working diligently to make this transition as smooth as possible for

you. However, as a result of this transition, the products and related documentation contained in this

shipment may be labeled with either the Hewlett-Packard name and logo, the Agilent Technologies

of

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(HP), but applies to your Agilent Technologies product. Hewlett-Packard and Agiient branded

products with the same model number are interchangeable.

Whatever logo you see, the information, products, and services come from the same reliable source.

If

you have questions about Agilent Technologies products and services, please visit our website at

http://www. anilent.com.

both. Information in this package may refer to Hewlett-Packard

Sincerely,

Rebranding

Team

HP

8903B

2450A

AUDIO

(Including Option

ANALYZER

001)

Operation and Calibration Manual

SERIAL

This

manual applies directly to instruments with

serial numbers prefixed

to

2922A

For

numbers, refer

THIS

and all

additional important information about serial

MANUAL’’

Mqior

to

“INSTRUMENTS COVERED in Section

NUMBERS

changes that apply

rev.ZOJUN91

1.

Fourth Edition

to

your

instrument.

BY

This

material may be reproduced by Government pursuant der the clause at

Copyright

EAST 24001

Operation and Calibration Manual HP Part 08903-90079

Other Documents Available: Service Manual (Volume Microfiche Operation and Service Manual HP Part 08903-90080

MISSION

1,

2)

HP Part 08903-90062

GHEWLETT-PACKARD COMPANY 1985

AVENUE, TAF C-34, SPOKANE, WASHINGTON, U.S.A. 99220

to

DFARS

the Copyright License

52.227-7013

or

for the

(AF’R

US.

un-

1988).

Printed in U.S.A. : November 1989

HEW

PACKARD

LETT@

1

Regulatory Information

(Updated

March

1999)

1

Regulatory

Safety Considerations

Information

(Updated

March

1999)

GENEFtAL

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

Publication

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

or

product input wiring terminals, power cord, SAFETY

A

Indicates instrument damage can occur

A

Indicates hazardous voltages.

&

-

Indicates earth (ground) terminal

WARNING

SYMBOLS

A

WARNING

~~~~ ~

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

practice, or the like, which,

could result in personal injury.

if

supplied power cord set.

indicated operating limits are exceeded.

~ ~

if

not correctly performed or adhered to,

Do

not proceed beyond a

WARNING

sign until the indicated conditions are fully understood and met.

~

A

CAUTION

CAUTION note denotes a hazard. It calls attention

procedure, practice,

to,

could result in damage

or

the like, which, if not correctly performed

to

or

destruction

of

part

to

an operation

or

all of the product. not proceed beyond an CAUTION note until the indicated conditions are hlly understood and met.

1010,

or

adhered

to

Do

a

the

2

Chapter

1

Safety Considerations for this Instrument

Regulatory

Information

(Updated

March

1999)

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 product dangerous. Intentional interruption

Whenever it

is

likely that the protection has been impaired, the

is

to

make the

prohibited.

instrument must be made inoperative and be secured against any unintended operation.

If

this instrument

voltage reduction), make sure the common terminal

is

to be energized

via

an auto transformer (for

is

connected

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

normal condition (in which

No

operator serviceable parts in this product. Refer servicing to

all

means for protection are intact) only.

qualified personnel. To prevent electrical shock, do not remove covers.

Servicing instructions are for use by qualified personnel only. To

avoid electrical

qualified to do

shock,

so.

do not perform any servicing unless you are

to

a

The opening

dangerous voltages. Disconnect the product from

while it The power cord

live for

5

of

covers

is

being opened.

is

or

removal of parts

connected to internal capacitors that

seconds after disconnecting the plug

is

likely to expose

all

voltage sources

from

its

my

remain

power supply.

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

only with example, normal blow

250

V

fuse(s) or the same current rating and type (for

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

Pollution Degree INDOOR

is

USE

designed for use in Installation Category

2

per

IEC

1010

and

IEC

664

respectively. FOR

ONLY.

I1

and

This product has autoranging line voltage input, be sure the supply voltage is within the specified range.

~~~~

Chapter

1

3

Regulatory Information (Updated

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.

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 watts dissipated in the cabinet. cabinet

is

used.

March

1999)

greater than

Do

not attempt to clean internally.

4"

C

for every

If

the total power dissipated in the

800

watts, then forced convection must be

100

Product

Markings

CE - the CE mark accompanied by

CSA

-

the

CSA

a

mark

is

a registered trademark

of

the European Community. A CE mark

year indicated the year the design was proven.

is

a registered trademark

of

the Canadian Standards Association.

4

Chapter

1

CERTIFICATION

Hewlett-Packard Company certifies from

the factom. Hewlett-Packard further certifies that its calibration measurements are traceable to the

United States National Bureau of Standards, to the extent allowed

that

this

product met

its

published specifications at

by

the

Bureau's calibration facility, and

the

time of shipment

to the calibration facilities of other International Standards Organization members.

WARRANTY

This Hewlett-Packard instrument product is warranted against defects

date

period of one year from option, either repair

For

warranty senrice shall prepay shipping charges to However, Buyer shall pay all shipping charges, duties, and taxes for products returned country.

HP warrants that its software and firmware designated by HP for use with an instrument will execute its programming instructions when properly installed on that instrument. HP does not warrant that the operation of the instrument,

The foregoing warranty shall not apply to defects resulting from improper Buyer, Buyer-supplied software environmental specifications

NO OTHER WARRANTY IMPLIED WARRANTIES

or

of shipment. During the warranty period, Hewlett-Packard Company will at

replace products which prove

repair, this product must be returned

HP

and HP shall pay shipping charges to return the product

or

sohare,

or

firmware will be uninterrupted

LIMITATION

or

interfacing, unauthorized modification

for

the product,

IS

EXPRESSED OR IMPLIED. HP SPECIFICALLY DISCLAIMS THE

OF

MERCHANTABILITY AND FITNESS FOR A PAWICULAR PURPOSE.

or

to

be defective.

to

a service facility designated by HP. Buyer

OF

WARRANTY

improper site preparation

in

material and workmanship for a

to

the Buyer.

to

HP from another

or

error free.

or

inadequate maintenance by

or

misuse, operation outside of the

or

maintenance.

its

EXCLUSIVE REMEDIES

THE REMEDIES PROVIDED HEREIN ARE BUYERS SOLE AND EXCLUSIVE REMEDIES.

HP

SHALL NOT BE LIABLE FOR CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT, TOFU', OR LEGAL THEORY.

ANY

DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR

ANY

OTHER

ASSISTANCE

Product maintenance agreements and other customer assistance agreements are available for HewlettPackard products.

For

any assistance, contact your nearest Hewlett-Packard Sales and Service Office. Addresses are provided

at the back

of

this manual.

Safety Considerations

Model

8903B

SAFETY

GENERAL

This product and related documentation must be reviewed for familiarization with safety markings and instructions before operation.

This product with a protective earth terminal).

BEFORE

Verify that the product is set to match the available line voltage and the correct fuse

SAFETY EARTH GROUND

An uninterruptible safety earth ground must be provided from the main power source to the product input wiring terminals, power cord, set.

SAFETY SYMBOLS

/I\

is

necessary for the user to refer to the instruction

manual (refer to Table of Contents).

is

a Safety Class I instrument (provided

APPLYING

Instruction manual symbol: the product will be marked with this symbol when

Indicates hazardous voltages.

POWER

or

is

installed.

supplied power cord

CONSIDERATIONS

it

(WARNING

Any interruption of the protective (grounding) conductor (inside ment) terminal will cause a potential shock hazard that could result ing one conductor of a two conductor outlet is not sufficient protection).

been impaired, the instrument inoperative and be secured against any unintended operation.

If this instrument is to be energized via an autotransformer (for voltage reduction) make sure the common terminal earth terminal

Servicing instructions are

trained personnel only. electric shock, do not perform any servicing unless qualified to do

or

disconnecting the protective earth

Whenever it

is

likely that the protection has

of

or

in

personal injury. (Ground-

the power source.

so.

I

outside

is

for

To

the

must

be made

connected to the

use by service-

avoid dangerous

instru-

Indicates earth (ground) terminal.

The WARNING sign denotes a

hazard. It calls attention to a procedure, practice, performed

jury.

the indicated conditions are fully understood and met.

operating procedure, practice, correctly performed age to not proceed beyond a CAUTION sign until the indicated conditions are fully understood and met.

or

Do

not proceed beyond a WARNING sign until

or

destruction of part

or

the like, which,

adhered to, could result in personal in-

The

CAUTION

ard. It calls attention to an

or

adhered to, could result in dam-

or

all of the product.

if

not correctly

sign denotes a haz-

the like, which, if not

Do

Adjustments described formed with power supplied to the instrument while protective covers are removed. Energy available at manypoints may, sult in personal injury.

Capacitors inside the instrument may still be charged even connected from its source of supply.

For

continued protection against fire hazard, replace the line fuse(s) only with of the same current rating and type (for exam-

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

rep a ired fuses

fuseholders.

if

the instrument

in

the manual are per-

if

contacted, re-

has

250V

Do

o

r

s

ho r t

c irc

been dis-

fuse(s)

not use

u

i

t ed

Model

8903B

Safety Considerations

ATTENTION

Static Sensitive

Devices

This instrument was constructed in an ESD (electro-static discharge) protected environment. This is because most of the semiconductor devices used by static discharge.

Depending on the magnitude of the charge, device substrates can be punctured charge. The results can cause degradation of device performance, early failure,

These charges are generated tact, separation of materials, and normal motions of persons working with static sensitive devices.

When handling devices, adequate precautions must be taken to prevent device damage

or

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 DEVICES,’

or

destruction.

in

Section VIII Service Section.

in

this

instrument are susceptible to damage

destroyed by contact

immediate destruction.

in

or

servicing equipment containing static sensitive

or

mere proximity of a static

numerous ways such

FOR

STATIC SENSITIVE

as

simple con-

HP 8903B

Table

of

Contents

TABLE

Section +General Information

Introduction Specifications Safety Considerations Instruments Covered By Manual

Manualchanges

Description

General Audio Testing Transceiver Testing Systems

Options

Electrical Options Mechanical Options

Hewlett-Packard Interface Bus

Compatibility

Selecting the HP-IB Address Accessories Supplied Electrical Equipment Available

HP-IB Controllers Front-to-Rear-Panel Connectors Retrofit Kit Rear-to-Front-Panel Connectors Retrofit Kit

Mechanical Equipment Available

Chassis Slide Mount Kit Chassis Tilt Slide Mount Kit

Recommended Test Equipment

Principles

Voltmeter and Notch Filter Counter Source Controller

Basics

of ACLevel Frequency DCLevel Signal Impurities Distortion SINAD Signal-to-Noise Ratio Internal Source Plotting

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

of

Operation

for

Simplified Block Diagram

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

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

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

Audio Measurements

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

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

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

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

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

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

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

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

OF

CONTENTS

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

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

1.1

1-1

1.2

1.2 1-2

1-3

1-4

1-5

1-6 1-6

1-6

1-8

1-8 1-8 1-8

1-8

1-9 1-9 1-9 1-9 1-9

1-10

1-11

1-12 1-12 1-12 1-13

1-13

1-15 1-15 1-16

1-16

Table

of

Contents

Section 2-Installation

HP

8903B

Introduction Initial Inspection Preparation

Power Requirements Line Voltage and Fuse Selection

Power Cables

HP-IB Address Selection Interconnections Mating Connectors

Operating Environment

Bench Operation

Rack Mounting

Storage and Shipment

Environment Packaging

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

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

for

Use

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

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

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

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

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

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

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

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

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

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

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

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

Section %Operation

Introduction

General Operating Characteristics

"urn-On Procedure Local Operation Remote Operation

Operator's Checks

Operator's Maintenance

Front-Panel Features Basic Functional Checks

Simplified Operation Rear-Panel Features

Description Equipment

Procedure

Preliminary Check AC Level and Output Level Check

Filter Check Distortion Check

SINAD Check Signal-to-Noise Ratio Check

Sweep, X Axis, Y Axis, Pen Lift, and DC Level Check

HP-IB Functional Checks

Description Initial Setup Equipment

Address Recognition Remote and Local Messages and the LCL Key

Sending the Data Message Receiving the Data Message

Local Lockout and Clear Lockout/Set Local Messages

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

2.1

2.1 2-2

2.2

2.3

2.5

2.6

2.8

-3-1 3-1

3-1 3-1

3-2 3-3

3-3 3-4 3-6

3-12

3-8

3-11

3-12 3-12 3-12 3-12

3-12 3-13

3-15 3-15

3-16 3-16 3-16 3-16

3-16 3-17

3-17 3-18

3-18

HP 8903B

Table

of

Contents

ClearMessage AbortMessage Status Byte Message Require Service Message Trigger Message and Clear Key Triggering

Remote Operation. Hewlett-Packard Interface Bus

HP-IB Compatibility Remote Mode LocalMode Addressing Data Messages Receiving the Data Message Sending the Data Message Receiving the Clear Message Receiving the Trigger Message Receiving the Receiving the Local Message Receiving the Local Lockout Message Receiving the Clear Lockout/Set Local Message Receiving the Pass Control Message Sending the Require Service Message Selecting the Service Request Condition Sending the Status Byte Message Sending the Status Bit Message

Receiving the Abort Message HP-IB ACLevel

Amplitude

Automatic Operation CommonMode

DCLevel Default Conditions and Power-up Sequence

Detector Selection

Display Level in Watts

Display Source Settings

Distortion Distortion Level Error Disable

Error Message Summary Filters Float Frequency Hold Decimal Point Hold Settings HP-IB Address 3-79 Increment Input Level Range (DC Level) Input Level Range (Except DC Level)

Monitor

Notch~ne

Output Impedance Plot Limit 3-96

Post-Notch Detector Filtering (Except SINAD)

Syntax

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Remote

Message

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

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

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

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

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

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

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

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

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

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

and Characteristics Summary

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

3-18

3-19

3-20 3-21 3-22 3-22 3-23 3-23 3-23 3-23 3-26 3-26 3-30 3-31 3-32 3-32 3-33 3-33 3-33 3-33 3-33 3-34 3-34 3-35

3-35

3-35 3-42 3-44 3-46 3-47 3-50 3-52 3-53 3-55 3-57 3-58 3-60 3-62 3-64 3-68 3-72 3-74 3-76 3-78

3-82 3-84 3-86 3-88

3-91

3-93

3-98

Table of Contents HP 8903B

Post-Notch Gain Rapid Frequency Count Rapidsource RATIO and LOG/LIN Read Display Service Request Condition Signal-to-Noise Special Functions Sweep Sweep Resolution Time Between Measurements X-YRecording

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

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

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

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

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

to

HP-IB

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

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

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

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

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

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

Section 4-Performance

Introduction Equipment Required TestRecord

Calibration Cycle Abbreviated Performance Testing

Performance Test

Performance Test Performance Test 3 Distortion and Noise Performance Test 4 Distortion, SINAD, and Signal-to-Noise Accuracy Performance Test 5 Frequency Accuracy and Sensitivity Performance Test 6 Audio Filters Performance Test Performance Test

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

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

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

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

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

1

AC

Level Accuracy and Output Level Accuracy and Flatness

2

DC Level Accuracy

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

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

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

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

7

Input and Output Impedance

8

Common-Mode Rejection Ratio

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

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

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

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

3-100 3-102 3-105 3-109 3-112 3-114 3-116 3-121

3-128 3-131 3-134 3-135

4.1

4.1 4-1

4.1

4-2 4-12 4-14 4-16 4-19 4-21 4-28 4-29

Section 5-Adjustments

Introduction Safety Considerations Equipment Required Factory-Selected Components Post-Repair Tests, Adjustments, and Checks Related Adjustments Adjustment Adjustment Adjustment 3 Common Mode Rejection Adjustment 4 Input DC Adjustment 5 400 Hz High-Pass and Weighting Bandpass Filters Adjustment 6 Notch Filter Tune and Balance Adjustment Adjustment Adjustment 9 Oscillator and Output Attenuator

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

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

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

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

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

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

1

Internal Reference Frequency

2

Input Flatness

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

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

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

Offset

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

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

7

Voltmeter

8

SINAD Meter

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

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

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

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

5.1

5.2

5.4

5.5

5.8

5.9 5-10 5-12 5-13 5-15 5-16

Model

8903B

General Information

1-1.

INTRODUCTION

This manual contains information required to install, operate, test, adjust, and service the HewlettPackard Model 8903B Audio Analyzer. This manual documents options installed in the Audio Analyzer such

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

address selection for remote operation), and storage and shipment.

Section

operating instructions for both local and remote operation, and maintenance information.

Section

instrument against the critical specifications in Table

Section

1

GENERAL INFORMATION

as

rear-panel connections and internal plug-in filters.

2,

Installation:

3,

Operation:

4,

Performance Tests:

provides information about initial inspection, preparation for use (including

provides information about panel features, and includes operating checks,

provides the information required

1-1.

to

check performance of the

Section

Sections 1 through 5 are bound in this volume, the Operation and Calibration Manual. One copy of the Operation and Calibration Manual is supplied with the instrument. Sections 6 through in

two

instrument unless specifically requested (as Option 915) at time of instrument order. Copies of all volumes can be ordered separately through your nearest Hewlett-Packard office. The part numbers 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 Each microfiche contains up to 96 photo-duplicates of the manual’s pages. The microfiche package also includes the latest MANUAL UPDATES packet, as well as all pertinent Service Notes.

1-2.

SPECIFICATIONS

Instrument specifications are listed in Table which the instrument may be tested. Characteristics listed under Supplemental Information, Table are not warranted specifications but are typical characteristics included as additional information for the user.

5,

Adjustments:

6,

Replaceable Parts:

7,

Instrument Changes:

8,

Service:

separate volumes, the Service Manual. Copies of the Service Manual are not supplied with the

provides the information required to properly adjust the instrument.

provides ordering information for all replaceable parts and assemblies.

provides instrument modification recommendations and procedures.

provides the information required

x

150

mm

1-1.

These are the performance standards, or limits against

to

repair the instrument.

(4

x

6 inch) microfilm transparencies of this manual.

8

are bound

1-2,

1-1

General Information Model

1-3.

SAFETY CONSIDERATIONS

8903B

This product is a Safety Audio Analyzer and all related documentation must be reviewed for familiarization with safety markings and instructions before operation. Refer to the Safety Considerations page found at the beginning of this manual (installation, performance testing, adjustment,

1-4.

INSTRUMENTS COVERED

Serial

stamped on the serial number plate attached to the rear letter constitute the serial number prefix, and the last five digits form the suffix. The prefix is the same for all identical instruments. however, apply directly to instruments having the same serial prefix(es) as listed under SERIAL NUMBERS on the title page.

Options.

documented in this manual. The differences are noted under the appropriate paragraph such in Section

1-5.

MANUAL UPDATES

An instrument manufactured after the printing of this manual listed on the title page. Having a serial number prefix that indicates that the instrument is slightly different from those documented in the manual. In this case, your manual information includes any hardware manual.

Class

I instrument (that is, provided with a protective earth terminal). The

for

a summary of the safety information. Safety information pertinent to the task at hand

or

service) is found throughout the manual.

BY

MANUAL

Numbers.

is

assigned sequentially and is different for each instrument. The contents of this manual

Electrical Option

1,

This instrument has a two-part serial number in the form

of

the instrument. The first four digits and the

It

changes only when a change

001,

internal plug-in filter options, and various mechanical options are

the Replaceable Parts List, and the schematic diagrams.

is

provided with updating information to make it as current

or

software changes that have occurred as well as corrections to the

is

made to the instrument. The suffix,

may

is

greater than that shown on the title page

OOOOAOOOOO

have a serial prefix that

as

possible. This updating

which is

as

Options

is

not

A Description

A

“MANUAL UPDATES” packet is shipped with the Operation and Calibration Manual when necessary to provide you with the most current information available at the time packets consist of replacement and addition pages which should be incorporated into the manual to bring it up to date.

Signing Up

Hewlett-Packard offers a Documentation Update Service that will provide you with further updates and changes as they become available. If you have not received update information that matches the serial number of your instrument, you can receive this information through the Update Service.

If

you

join this service immediately to ensure that your manual is kept current. For more information, refer

to the Documentation Update Service reply card included in this manual

Hewlett-Packard Company Technical Writing Department 24001 Spokane, WA. 99220 (509) 922-4001

of

the Manual Update Packet

for

the Documentation Update Service

operate

E.

or

service instruments with different serial prefixes, we strongly recommend that you

Mission-TAF C-34

or

contact:

of

shipment. These

1-2

Model 8903B

1-6.

DESCRIPTION

General

The HP Model 8903B Audio Analyzer is a complete audio measurement system covering the frequency range of source has a maximum open-circuit output of 6 Vrms and a selectable output impedance of either

6000. The analyzer can perform distortion analysis, frequency count, and ac level, dc level, SINAD, and signal-to-noise ratio measurements. The Audio Analyzer reduces the number of instruments required in many applications involving audio signal characterization.

20

Hz

to

100 kHz.

General Information

It

combines a low-distortion signal source with a signal analyzer. The

50

or

The Audio Analyzer is easy distortion measurements, the Audio Analyzer automatically tunes to and levels the input signal. Measurement and output ranges are automatically selected for maximum resolution and accuracy. firthermore, tuning is independent of the source. Thus, the source can be set to one frequency while

is

the analyzer tune the analyzer

The combined capabilities of the instrument are enhanced by microprocessor control, resulting capability than would be available from separate instruments. For example, when making signal-to-noise ratio measurements, the Audio Analyzer monitors the ac level while turning the source on and microprocessor then computes and displays the ratio of the on and in either

In addition, the source can be swept. This makes measurements such as frequency response

distortion characterization simple

parameters and versatile display formats. For example, ac level can be displayed in V, mV, dBm into

6000, watts,

Virtually all functions are remotely programmable through the Hewlett-Packard Interface Bus

(HP-IB'). Programming is easy input. This eliminates the need to switch between multiple inputs under remote control and reduces software development time and hardware costs. The Audio Analyzer measures the true rms level on all ac measurements. True rms measurements assure greater accuracy when measuring complex waveforms and noise. For those applications where average detection be switched to average-responding distortion measurements typically can be made to less than

20

kHz

at

(Serial Prefix 2730A and above) can be switched This detector is designed

measuring the distortion on a signal

to

the source).

5%

or

dB.

or

as a ratio (in

a 1.5V level. For those applications where quasi-peak detection

to

use. All measurements are selected by one

at

another frequency (that is, there

off

levels. The ratio can be displayed

to

perform. Microprocessor control allows flexible entry of source

%

or

dB)

referenced to an entered

and

straightforward; all measurements are made through a single

(rms

calibrated) detection through special functions. Accurate

to

this type of detection through special functions.

to

meet the requirements specified by CCIR 468-3.

or

measured value.

0.003%

or

two keystrokes. For

is

no need to

or

complete

is

required, the analyzer can

(-90

dB)

between

is

required, the analyzer

20

in

more

off.

The

Hz and

Audio Testing

The Audio Analyzer has numerous features which make audio testing simple and convenient. These features include flexible data entry and display formats, convenient source control, and swept

For

measurements capability. measurements can be displayed in volts, dBm into 600R,

%

or

dB

in is simplified by using the source frequency increment and decrement keys together with the relative display feature. When sweeping, the Audio Analyzer tuning steps an x-y recorder, hard copy measurement results can be obtained. X-axis scaling entered start and stop frequencies. Y-axis scaling the plot limits entered through the keyboard. Any valid display units (except mV) are allowed when

plotting. To change the scaling from frequency response to swept distortion plots, simply key in new

HP-IB: Not just IEEE-488, but the hardware, documentation and support that delivers the shortest path to a measurement system.

relative to a measured

A

major contribution of the Audio Analyzer is its ability to make swept measurements.

example, distortion results can be displayed in

or

watts. Measurement results can be displayed

or

entered value. Finding the

its

source frequency in logarithmic increments. With

is

determined by the measurement units selected and

3

dB

points of filters and amplifiers

%

or

dB.

AC level

is

determined by the

1-3

General Information Model

8903B

values for the plot limits.

No

adjustment of the x-y recorder

is

necessary. The Audio Analyzer also features high accuracy. The instrument can typically measure flatness of

20

Hz to

20

and

1-2.

kHz and swept distortion over the same range to

Figure

9

w

v,

p

'0

g

'?o

-

I-

+0.2,

1-1.

npical Combined Source and

-70

-75

-80

-85

I,,

0.003%

AC

!

9

-95

D

2

-100

3

0

-105

v)

-110

20Hz

5OHz

2OOHz

500Hz

FREQUENCY

PkHr

5kHz

to

0.5%

(0.05

(-90

dB).

I1

Level Flatness

20kHz

dE3)

over the range

See Figures

1-1

Balanced

Figure

Input.

1-2.

Typical Combined Source and Analyzer Residual Distortion

(80

kHz

With Vsource Set to 1.5V

BW)

The Audio Analyzer has a selectable balanced input configuration for testing balanced devices. For example, in the quest for higher output power, many audio amplifiers use bridged output stages. Such amplifiers can be difficult to characterize because their outputs cannot be grounded. To

to

test these devices, the usual approach has been

use a balanced, calibrated isolation transformer connected to an analyzer with an unbalanced input. Balanced inputs on the Audio Analyzer make transformers unnecessary. With the analyzer input in the float position, connect the bridged device directly to the Audio Analyzer to make measurements.

Transceiver Testing

The Audio Analyzer has several measurements and features specifically designed for transceiver testing.

It

has SINAD and signal-to-noise ratio measurements for receiver testing, optional internal plug-in

weighting filters for testing to international standards, a reciprocal counter for measuring squelch tones,

400

and an optional internal plug-in

Hz high-pass

transmitter audio distortion.

SINAD is one sensitivity

of

the most basic receiver measurements. It must be made repeatedly when performing

or

adjacent-channel sensitivity tests. In the Audio Analyzer, the SIN AD 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 excellent repeatability and speed typical). Some automatic distortion analyzers have

SINAD on noisy signals. The Audio Analyzer overcomes this problem by tuning the notch filter to

filter

for eliminating squelch tones when measuring

(2

readings/second

a

tendency to become untuned when measuring

1-4

Model

8903B

the source frequency when measuring SINAD. SINAD measurement results are indicated both by the digital display and a front-panel analog meter. The meter is specifically marked for

25

dB,

sensitivity and selectivity. For SINAD ratios less than

0.5

dB

rounded to the nearest Signal-to-noise ratio measurements are also filtered for improved repeatability and speed

ing/second typical), and automatic display rounding Audio Analyzer uses true

instruments employ average detection which reads low for noise. The discrepancy can be greater and varies with the ratio being measured. For correlating results with past test data, the Audio Analyzer’s detector can be switched via special functions

For those applications where quasi-peak detection is required, the analyzer (Serial Prefix above) can be switched

to

meet the requirements specified by CCIR

For transceivers, the Audio Analyzer has an optional, internal plug-in seven-pole 400 Hz high-pass filter for rejecting squelch tones. Rejection of squelch tones up to audio distortion measurements squelch tones.

Under remote control, the Audio Analyzer can generate

is

maximum count rate applications such as unsquelching pagers (see Figure

8

to reduce digit flicker.

is

provided. For accurate noise measurements, the

rms

detection for both SINAD and signal-to-noise measurements. Most older

to

this type of detection through special functions. This detector is designed

468-3.

to

1%

residual distortion can be made without disabling the transmitter

or

ms/reading and the minimum tone duration

1-3).

the digital display

an average responding configuration.

250

Hz

is

greater than

count burst tone sequences. Typically the

is

12

General Information

EIA

is

40

dB.

ms. This

is

fast

and CEPT

automatically

1.5

2730A

Therefore,

enough for

(1

read-

dB

and

or

Figure

1-3.

Two-Tone

Burst

Sequence

(15

ms

Duration)

Systems

The Audio Analyzer features capabilities for general systems applications. The audio source

programmable in frequency, level, and output impedance has very low distortion. The distortion measurements are fully automatic, programmable, and

is

1.5

first distortion measurement The combined distortion of the internal source together with the measurement section is typically

0.003%

Often systems applications involve measuring low level ac signals. The Audio Analyzer features a full

range ac level display of and from Quasi-peak detection. The

Since many systems have noise problems, the Audio Analyzer has both

reject high frequency noise. In addition, the optional internal plug-in line-related hum and noise by more than

Two special binary programming modes are available in remote operation. A rapid frequency count mode provides a packed, four-byte output for fast counting. Also, a rapid source binary programming mode of data.

(-90

dB)

between

20

Hz

to

20

is

available which allows the internal oscillator tuning to be programmed directly with five bytes

20

0.3000

kHz). The ac detector is switchable between true rms, average-responding, and

3

seconds with a measurement rate of 2 readings/second thereafter.

Hz

and

20

kHz at a

mV with an accuracy of

dB

measurement bandwidth for each detector is greater than

68

dB.

1.5V

fast.

The typical time

level.

4%

of reading

to

(2%

of reading for levels

30

and

80

kHz low-pass filters

400

Hz

high-pass filter attenuates

tune and return the

500

>50

kHz.

is

mV

to

1-5

General Information

1-7.

OPTIONS

Electrical Options

Model 8903B

Electrical Option

001.

This option provides rear-panel (instead of front-panel) connections for both

the INPUT and OUTPUT HIGH and LOW BNC connectors.

Internal Plug-in Filter Options.

The Audio Analyzer has

two

plug-in filter positions; each position can be loaded with any one of six optional filters. Each filter is referenced to its corresponding filter position by one as Option 010 which corresponds to the left-most filter position,

of

two

option numbers. For example, the 400 Hz high-pass filter option can be ordered

or

as

Option

050

which corresponds to the right-most filter position. These optional plug-in filters can be configured in any combination desired.

there is no filter ordered for a position, a jumper

is

loaded and a label marked

(If

is placed above the filter key on the front panel.) The following list includes the name and option numbers for each available filter.

0

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

0

CCITT Weighting Filter (Option 011, 051)

0

CCIR Weighting Filter (Option 012, 052)

0

C-MESSAGE Weighting Filter (Option 013, 053)

0

CCIR/ARM Weighting Filter (Option 014,

0

“A”

Weighting Filter (Option 015,

055)

054)

Specific information on each plug-in filter option can be found in the Detailed Operating Instructions in Section 3 under “Filters”.

Mechanical Options

The following options may have been ordered and received with the Audio Analyzer. ordered with the original shipment and are now desired, they can be ordered from the nearest HewlettPackard office using the part number included in each of the following paragraphs. The mechanical options are shown in Figure 1-4.

If

they were not

“No

Filter”

Front Handle Kit (Option

HP

part number 5061-9689.

Rack Flange

Kit

(Option

907).

908).

Ease of handling

is

increased with the front-panel handles. Order

The Audio Analyzer can be solidly mounted to an instrument rack

using the flange kit. Order HP part number 5061-9677.

Rack Flange and Front Handle Combination Kit (Option 909).

a

a rack flange kit packaged together; it is composed of

HP

Order

part number 5061-9683.

unique part which combines both functions.

This

is

not a front handle kit and

1-6

Model

8903B

General Information

SPARE INTERNAL FUSES

OPTION

909

RACK FLANGE AND FRONT

HANDLE COMBINATION KIT

BNC TO BANANA PLUG ADAPTERS

’

OPTION907

FRONT HANDLE KIT

Figure

1-4.

OPTION

908

RACK FLANGE KIT

NOTE:

Refer

to

ACCESSORIES

HP

8903B Accessories Supplied, and Options

SUPPLIED,

for

more

details.

907,

908, and 909

1-7

General Information Model 8903B

1-8.

HEWLETT-PACKARD INTERFACE BUS

Compatibility

The Audio Analyzer is compatible with HP-IB to the extent indicated by the following code: SH1,

T5,

AH1,

bus via open collector TTL circuitry. An explanation of the compatibility code can be found in IEEE

Standard 488, ANSI Standard MC1.l. Analyzer, refer to

TEO, L3, LEO,

IEEE Standard Digital Interface for Programmable Instrumentation

Remote Operation, Hewlett-Packard Interface

SR1,

RL1, PPO, DC1, DT1,

For

more detailed information relating to programmable control of the Audio

CO,

El.

The Audio Analyzer interfaces with the

or the identical

Bw

in Section 3 of this manual.

Selecting the HP-IB Address

The HP-IB address switches are located within the Audio Analyzer. The switches represent a fivebit binary number. This number represents the talk and listen address characters which an HP-IB

two

controller is capable of generating. In addition, to talk only

HP-IB

1-9.

ACCESSORIES SUPPLIED

or

Address Selection

listen only. A table in Section 2 shows all HP-IB talk and listen addresses. Refer to

in Section 2

of

this manual.

more switches allow the Audio Analyzer to be set

The accessories supplied with the Audio Analyzer are shown in Figure

Fast

blow fuses with a 1.5A rating for 100/120 Vac operation (HP 2110-0043) and a

220/240 Vac operation (HP 2110-0001) 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

1-1

the customer. to the country of destination.

Four type BNC-to-banana-plug adapters (HP 1250-2164) are also supplied for use when double-ended

inputs

conductor of the BNC connector adapted to. These adapters are used when the front-panel INPUT

or

0.

ELECTRICAL EQUIPMENT AVAILABLE

(Also refer to Service Accessories, Table

HP-I6

The Audio Analyzer has controller

or

OUTPUT FLOAT switches are set to FLOAT.

Controllers

If

the voltage

outputs are desired. The conductor of the banana connector is connected to the center

or

computer for automatic systems applications.

is

not specified, the rating of the installed fuse will be selected according

an

HP-IB interface and can be used with any HP-IB compatible computing

Front-to-Rear-Panel Connectors Retrofit Kit

This kit contains all the necessary components and full instructions for converting instruments with front-panel connections for INPUT and OUTPUT HIGH and LOW to rear-panel connections. serial prefixes 2730A and below, order above, order HP part number 08903-60199. After installation and calibration, performance will be identical to the

HP

8903B Option 001.

1-4.

1.OA

1-4.)

HP

part number 08903-60171. For serial prefix 2742A and

rating for

For

Rear-to-Front-Panel Connectors Retrofit Kit

This kit contains all the necessary components and full instructions for converting instruments with rear-panel connections for INPUT and OUTPUT HIGH and serial prefix 2730A and below order HP part number 08903-60172. order HP part number 08903-60200. After installation and calibration, performance will be identical to the standard HP 8903B.

1-8

LOW

to front-panel connections. For

For

serial prefix 2742A and above,

rev.26JU.9

Model

1-1

1.

8903B

MECHANICAL EQUIPMENT AVAILABLE

General Information

Chassis

This kit components part number adapters for non-HP rack enclosures.

Chassis Tilt

This kit instrument up

part

AC/OC

HIGH

IN^

c>-

I" I

%?

ACfOC

Slide

number

ATTFTOR

Mount Kit

is

extremely useful when the Audio Analyzer

or

the rear-panel

1494-0060

Slide

is

INPUT

-

Mount Kit

the same as the Chassis Slide Mount Kit above except

or

down

90".

1494-0061

OVER- TO-SINGLE- PROGRAMMABLE

VOLTAGE ENOEO- GAIN

PROTECTION

-

OVFII-

VOLTAGE

PROTECTION

for

OIFFERENTIAL-

AMPLICIER AMPLIFIER

VOLTAGETO-TIME

CONVERTER

is

possible without removing the instrument from the rack. Order HP

for

431.8

mm

(17

Order HP part number

the correct adapters for non-HP rack enclosures.

I

is

rack mounted. Access

in.) fixed slides and part number

it

also allows the tilting of the

INTERNAL

PLUG-IN

HP/BP

I

1494-0062

1I

FILTER

for

431.8

mm

PROGRAMMABLE PROGRAMMABLE

to

internal circuits and

1494-0061

(17

for the correct

in.) tilting slides and

!t

MONITOR

1-12.

1-13.

SINAO METER

-0

RB8giE;o

2

rn

KEYBOARO AN0 OISPLAY

a8

ooDD

..--

D

w..

0

-P

Figure

1-5.

Simplified

HP

8903B

Audio Analyzer

Block

Diagram

RECOMMENDED TEST EQUIPMENT

Table

1-3

lists the test equipment recommended for use in testing, adjusting, and servicing the Audio

If

Analyzer.

any of the recommended equipment

specifications may be substituted. Table

1-3

is

unavailable, instruments with equivalent minimum

also includes some alternate equipment listings.

PRINCIPLES OF OPERATION FOR SIMPLIFIED BLOCK DIAGRAM

The HP

a general purpose voltmeter with

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 Audio Analyzer also has selectable input filters, logarithmic frequency sweep,

outputs The operation

Counter, Source, and Controller. Refer to Figure

8903B

for

Audio Analyzer combines three instruments into one: a low-distortion audio source,

a

tunable notch filter at the input, and a frequency counter.

plotting measurement results vs. frequency, and HP-IB programmability.

of

the instrument

is

described in the following order: Voltmeter and Notch Filter,

1-5.

x

and

y

1-9

General Information Model

8903B

Voltmeter

The amplitude measurement path flows from the INPUT connectors (HIGH and LOW) to the MONITOR output (on the rear panel) and includes the Input RM$/Average and Output RMS/Average/QuasiPeak Detectors, dc voltmeter (the Voltage-to-Time Converter and Counter), and SINAD meter circuitry. Measurements are made on the difference between the signals at the HIGH INPUT connector and the LOW INPUT connector Signals that are common to both the HIGH and LOW connectors are balanced out.

The input signal Input Attenuator to Protection circuit opens whenever its input exceeds 15V. The differential signal single-ended signal (that is, a signal referenced to ground) and amplified. In the dc level mode, the dc voltage Gain Amplifier which Amplifier are programmed to keep the signal level into the Input Detector and Notch Filter between

1.7

modes. The output from the first Programmable Gain Amplifier 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 Detector and becomes the numerator of the SINAD measurement and the denominator of the distortion measurement (refer to to make the ac level measurement; the Output RMS/Average/Quasi-peak Detector is used for this measurement. For dc level measurements, the Ranging RMS Detector also monitors the ac component

(if there otherwise, the gain of the input path is determined by measuring the dc level. two internal plug-in filters can be inserted into the signal path. The used to suppress line hum weighting filters have bandpass frequency responses that simulate the “average” response 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, the Notch Filter. The output from the filter and signal-to-noise ratio modes the Notch Filter the output from the Notch Filter is converted to dc by the Output RMS/Average/Quasi-peak Detector and measured by the dc voltmeter.

When measuring distortion counted at the input to the filter. Coarse tuning circuitry internal to the Notch Filter. When measuring SINAD, the Notch Filter the Controller to the same frequency as the internal source. Thus, a SINAD measurement only made with the internal source as the stimulus and permits measurements in the presence large amounts of noise (where the Controller would be unable to determine the input frequency). external source

of

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

The 30 kHz and the 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 rear-panel MONITOR output connector. The frequency of this signal

ac

The Output Detector is read by the dc voltmeter in the ac level, SINAD (the denominator), distortion (the numerator), distortion level, and signal-to-noise ratio measurement modes.

and

Notch

is

measured at this point by the dc voltmeter. The signal

and 3 Vrms

is

one) and lowers the gain of the input path

the frequency of the internal source. The

3

dB

bandwidth of the measurement system is approximately

level

and signal-to-noise ratio measurement modes because of the increased sensitivity at this point.

Filter

(or

ground). Differential and common-mode levels can be as high as 300V.

is

ac coupled for all measurement modes except dc level. The signal

a

level of 3V

is

ac coupled. The gain

to

optimize their effectiveness and accuracy, particularly in the distortion and SINAD

Basics

or

less. To protect the active circuits that follow, the Over-Voltage

of

this amplifier and the Differential-to-Single-Ended

of

Audio Measurements).

is

further amplified by a Programmable

HP/BP

The Input RMS/Average Detector

if

the signal will overload the input amplifiers;

filters to the Input RMS/Average

At

400

Hz high-pass filter

or

the low frequency squelch tone used on some mobile transceivers. The

or

distortion level, the fundamental of the signal is removed by

is

the distortion and noise of the signal. In the ac level

is

bypassed. After amplifying and low-pass filtering,

or

distortion level, the Notch Filter

is

via the Controller. Fine tuning and balance are via

is

used in the SINAD measurement mode, the source frequency must be within

two

Programmable Gain Amplifiers, following the Notch

80

kHz LP Filters are selected from the Keyboard. With no low-pass filtering,

is

automatically tuned to the frequency

0.3

to 3V at the MONITOR output.

750

kHz. The filters are most

is

also measured by the Counter in the

It

is

scaled by the

is

converted

this point, one of the

is

coarse tuned by

is

is also used to set the

is

not used

is

usually

normally

If

to

5%

a

of

an

1-10

Model

8903B

gain

of

the

two

Programmable Gain Amplifiers. Both the input and output detectors can be configured via special functions to respond to the absolute average of the signal instead In the SIN AD mode the outputs from the Input RMS/Average and Output RMS/Average/Quasi-peak

of

Detectors are converted to a current representing the log of the ratio

to

Meter Amplifier

very noisy conditions, the panel meter makes The Voltage-to-Time Converter converts the dc inputs into a time interval which

Counter. The Output Detector can also be configured via special functions to respond

of the signal. This type of detector types. The Quasi-peak Detector has a fast rise time coupled with a slow decay time constant which “captures” impulses

drive the SINAD panel meter. Since SINAD measurements are often made under

it

or

other

signals

easier

is

designed

with a high crest factor (noise

to

average the reading and to discern trends.

respond to impulse type signals better than other

the

or

repetitive signal bursts).

General Information

of

the true

two

signals by the SINAD

is

measured by the

to

the quasi-peak

Counter

rms

value.

The Counter of the signal at The reference Counter has four inputs and three modes of operation:

Voltage Measurement.

accumulated count is proportional and distortion level), the count display. For ratio measurements (SIN measurements are processed and displayed. For SINAD and distortion, the ratio of the output of the Input RMS/Average Detector and Output RMSIAveragejQuasi-Peak Detector to-noise, the ratio of computed. One output is with the Oscillator on, the other is with the Oscillator

Input Frequency Measurement.

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 frequency is displayed on the left display.

Source Frequency Measurement.

when the Oscillator of the source frequency, the output

the result processed by the Controller.

is

a reciprocal counter. To measure frequency, it counts the period of one

its

input, then the Controller divides the number of periods by the accumulated count.

for

the Counter is the 2 MHz Time Base which also is the clock for the Controller. The

The time interval from the Voltage-to-Time Converter

to

the dc voltage.

is

processed directly by the Controller and displayed on the right

AD,

distortion, and signal-to-noise), the counts

two

consecutive outputs from the Output RMS/Average/Quasi-peak Detector is

The signal from the last Programmable Gain Amplifier or the HP/BP

The Counter measures the frequency

is

being tuned. The frequency is normally not displayed. To make a measurement

of

the Oscillator is fed

For

direct measurements (ac level, dc level,

is

computed. For signal-

off.

is

processed by the Controller, and the

of

the internal source only

into

the Counter, the period measured,

or

more cycles

is

counted. The

of

two

successive

and

Source

The source covers the frequency range from from Keyboard by the Controller using a tune-and-count routine. (Note that the frequency is not obtained by frequency synthesis.) The switch following the Oscillator is normally closed except in the signal-to-noise ratio measurement mode

is

The output from the Oscillator The Output Amplifier sets the source output level in fine steps. The Floating Output Amplifier converts

the single-ended input into a floating signal (either output can be grounded The Output Attenuator sets the output level in coarse steps. The maximum signal to the OUTPUT connectors is 6V into an open circuit the source is level.)

HP-IB

programmable to either

approximately

or

20

Hz

to

100

kHz.

It is tuned to the frequency entered

or

when an amplitude of OV

3V.

3V into the matching termination. The output impedance of

50

or

600R. (The keyboard-selected level

is

entered from the Keyboard.

or

floated up to

is

the open-circuit

1OV

peak).

1-11

General Information Model

Controller

The entire operation of the instrument is under control of a microprocessor-based Controller. The Controller sets up the instrument at turn-on, interprets Keyboard entries, executes changes of operation, continually monitors instrument operation, sends measurement results and errors to the

is

used

front-panel displays, and interfaces with HP-IB. In addition, its computing capability

For

circuit operation. into ratios (in

’3%

example, it forms the last stage of the Counter, converts measurement results

or

dB),

etc. It also contains routines useful for servicing the instrument.

to

8903B

in

mode

simplify

1-14.

AC

BASICS

The “audion frequency range is usually taken to be from that good, but the term is a convenient one to describe sub-RF frequencies encountered in electronics. The frequency range of the Audio Analyzer extends beyond the audio range up

Electronic instrumentation provides most of the tools for quantitative analysis of audio signals. Thus,

if

signal by a transducer of some kind (for example, strain gauge or microphone) before

Apart

in the audio range

frequency (pitch), and shape (timbre). You can also determine 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 parameter sought does not lend itself visual analysis. Thus, the Audio Analyzer was designed. 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.

OF

AUDIO MEASUREMENTS

to

100

kHz.

the signal is non-electrical (for example, mechanical

from attentive listening

is

visually with an oscilloscope. Here you get a feeling for the signal’s size (loudness),

to

a hi-fi system, the most intuitive way of analyzing an electrical signal

20

Hz to

or

acoustic),

It

combines into one instrument a series of

20

kHz. Few people have hearing

to

include fundamentals

it

must be converted

it

can be analyzed.

if

these parameters change with time

to

an electrical

to

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

rms

peak level to the the rms value

This measurement is greatly simplified with a rms voltmeter which electronically measures the rms level and displays the result. However, no other information about the signal is provided. The Audio Analyzer contains both an rms- and an average-responding voltmeter. The displayed whenever the AC SPCL. The quasi-peak level can be displayed by entering which converts the measurement result into watts for

is

level can be mathematically determined. If the signal is sinusoidal, for example,

the peak amplitude divided by

LEVEL

mode is selected. The average level can be displayed by entering

a.

rms

level of the signal

5.7

SPCL. A special function

a

specified (external) load resistance.

is

also provided

or

easy

is

5.2

1-12

Another important ac signal characteristic you can easily set a reference level (such as the change in level as the input frequency is changed. (The source’s level

too

must be checked.) The Audio Analyzer makes this measurement easier in three ways. First, the

it analyzer contains a flat, wide-range oscillator that can be used as the stimulus. Second, the reference

100%

or

0

dB

can be set to automatically swept and the results can be plotted by connecting an x-y recorder to the (rear-panel)

Y

X AXIS and 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. This measurement

is

made easier by the Audio Analyzer when used with

input level, then either measure

ratio reference. Then measure the output. The result can be expressed in either the input can be swept and the gain plotted

logarithmically, the result

AXIS outputs.

by the press of a button (the RATIO key). Third, the measurement can be

it

and set it as a reference (press RATIO)

is

a Bode magnitude plot if

is

the variation in level vs. frequency (flatness). Of course

1V)

at a particular frequency (such

is

its

internal oscillator. You

as

a function of frequency (since the frequency plots

dJ3

is

used).

as

assumed

first

or

key in the

1

kHz) and monitor

to

be flat; otherwise,

key in the desired

level

as the

’%

or

dB.

If desired,

Model

Frequency

8903B

General Information

Another common and basic measurement

time interval between like points on the repetitive waveform and take the reciprocal. With

is

counter, frequency much more accurate than could be made visually with an oscilloscope.

The Audio Analyzer contains a counter which displays the frequency of the input signal for all ac

measurements. the signal (as you do with an oscilloscope) and computes the reciprocal advantage of this technique measurement time.

DC

Level

Although not part of an audio signal, dc level example, bias voltages and outputs from ac-to-dc converters). Sometimes plots of dc level vs. frequency

(as

are desired The Audio Analyzer has dc level as one of

in the case of

measured electronically and displayed. The measurement

It

should be noted that the counter

is

that for low (audio) frequencies, higher resolution

an

ac-to-dc converter).

is

frequency. With an oscilloscope, you simply determine the

is

easier and usually

is

a reciprocal type; it measures the period

to

obtain the frequency. The

is

obtained in a shorter

is

a quantity often encountered in audio equipment (for

its

measurement modes.

Signal Impurities

Distortion, SINAD, and signal-to-noise ratio are used to describe the impurity content of a signal. These terms are somewhat related and

is,

sinusoid, that are not always undesirable. Impurities, for example, are what add character instruments. Pure a pure signal is applied

is

degrading the signal. There are several common classifications of impurities: harmonic distortion

(harmonics of the fundamental), intermodulation distortion (beat signals of

signals), noise (random signals), and spurious signals (for example, line hum and interference). All but intermodulation distortion are easily measured by the Audio Analyzer.

one whose frequency spectrum contains only a single spectral component. Impurities

signals

in music sound monotonous. However, when testing a linear audio system,

to

the input, anything but a pure signal at the output indicates that the system

can

often be confused. A pure signal

is

defined

to

the sound of musical

two or

as

more non-related

a

frequency

a perfect

of

if

Distortion

Harmonic distortion on a spectrally pure signal is created by non-linearities in the circuit through

it

which running the active device into saturation signal level, filtering,

According to Fourier mathematics, the non-linear terms in the circuit’s transfer function give rise harmonics of the signal. Total harmonic distortion (THD) is usually defined sum of the harmonics to the rms level of the fundamental. The ratio

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 a trained eye can discern distortion as low a examples of waveforms with 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, the best instrument to measure harmonic distortion. The audio spectrum analyzer method, however, requires a fairly expensive instrument and some mathematical manipulation.

passes. The non-linearities can arise in the transfer characteristics of the active devices

or

cutoff. Often, distortion can be reduced by reducing the

or

adding negative feedback.

as

the ratio of the rms

is

“gentle” (for example, not clipped),

5%

on an oscilloscope display. Figure

5%

THD and the components that combined

usually converted

to

produce them.

to

1-6

shows several

7%

or

is

perhaps

or

dB.

(5%

by

to

1-13

General Information Model

8903B

SIN X AND

SIN

X

+

0.05

SIN X AND

0.05

SIN

0.05

SIN

2X

3X

SIN X AND

SIN

X

+

0.05

SIN X AND

0.05

COS

0.05

COS

2X

COS

3X

2X

SIN

X

+

0.05

SIN

3X

Figure

1-6. Several Waveforms Each With

The traditional method

is

with a distortion analyzer. The method

of

measuring distortion (accepted by the Institute of High Fidelity and others)

5%

THD

is

analyzer, you simply measure the signal level and set

of

tuned to the frequency

the fundamental, and measure the’output of the filter relative to the input. This is the method used by the Audio Analyzer in the DISTN mode where the tuning and measuring are done automatically. When using the distortion analyzer method,

is

the measurement result

not “total harmonic distortion” as defined above except under the condition that the distortion is not too excessive but that it does predominate over any other signal impurities. Some examples will illustrate these restrictions.

The Institute of High Fidelity, Inc., Standard Methods High Fidelity, Inc., New

1-14

York

(1978),

p.

9.

SIN

X

+

0.05

COS

3X

and the Signal Components Which Produced Them

simple and adequate for most situations. With a distortion

it

up

as

a reference, then you insert a notch filter,

it

is

important to understand that

Of

Measurement

For

Audio Amplifiers,

The

Institute

of

Model

8903B

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

is

harmonic 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 the fundamental level were 1 Vrms, the second harmonic level would be fundamental). The total input level (measured with a true rms voltmeter) components, namely,

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 level. The distortion measured by a distortion analyzer will be 1.4% (that is, 40% then, can you be sure that the result is a valid measurement of distortion? One way (rear-panel) MONITOR output with an oscilloscope. If the waveform to the fundamental, the measurement are provided to remove unwanted signals. Use the optional 400 Hz High-Pass Filter hum. Use the filters that do not affect the fundamental and the harmonics of interest. Sometimes include hum and noise as part of the “distortion” measurement. For this reason, the measurement often referred to as a THD + N (total harmonic distortion plus noise) measurement.

then 20

is

1%

dJ3

below the fundamental as viewed on

Input

=

,/(1)2

+

(0.1)2

but that there is an additional hum component that has a level

is

actual total harmonic distortion.

30

kHz

or

80

kHz Low Pass Filter

to

remove out-of-band noise. However, select only

a’

spectrum analyzer. When this signal

as

the level of the fundamental.

=

1.005V

is

clean and harmonically related

0.1

If

General Information

Vrms (one-tenth of the

is

the rms sum of the

1%

of

the fundamental

or

3

dB

high). How,

is

to observe the

it

is not, selectable filters

to

remove line

it

is

desired to

is

If

two

is

SINAD

For most practical purposes the SINAD measurement, as made by the Audio Analyzer,

It

reciprocal of the distortion measurement. that the notch filter the signal at its input). This permits measurements in the presence of large amounts of impurities and

assures that the fundamental is tuned out.

frequency setting of the internal source.

SINAD is an acronym for SIgnal, Noise, And Distortion. The ratio (normally expressed in

computed in the

SINAD

The equation eliminates the

SINAD is used most often in determining the sensitivity of a receiver. Receiver sensitivity as the RF level that, when modulated in a specified manner with a pure audio tone, creates a certain

SINAD (usually 10

noise.) Sometimes a psophometric (that is, noise measuring) filter is required in the receiver sensitivity measurement. Optional plug-in weighting filters modify the frequency response of the Audio Analyzer with a bandpass characteristic that approximates the response of human hearing. Weighting filters which meet most international standards are available.

is

coarsely programmed to the frequency of the internal source (but fine tuned to

SINAD

measurement

=

20

or

12

dB)

rms value

log

two

rms value

restrictions discussed in connection with the distortion measurement.

at the receiver’s audio output. (The tone can just be discerned in the

is usually expressed in

If

an external source is used,

is

of

signal, ndse and distortion

of

ndse and distortion

dB.

The one subtle distinction

it

must be within 5%

is

equal

is

defined

to

of

dB)

the

is

the

Signal-to-Noise Ratio

Measurement of the signal-to-noise ratio requires the use of the Audio Analyzer’s internal source. The

off

Audio Analyzer simply turns the source (set to a specified level) on and

is

for both conditions. This comfortable volume, then lifting the tone arm and listening to the level

similar to the experience you have when listening to a recording at a

and measures the ac level

of

the residual hiss and hum.

1-15

General Information

Internal Source

Model 8903B

The internal source

is

distortion permits measurements

about the same

is

used when a low-distortion stimulus

as

that

of

the

Audio

Analyzer’s measurement system. The combination

of

distortion

as

low as

0.003%

(-90

for

the device under

dB).

test

is

Plotting

When used in conjunction with the sweep mode, any of the measurements vs. frequency can be plotted

using

the rear-panel stimulus. This simplifies traditionally time consuming measurements such as flatness, gain, distortion, and SINAD vs. frequency, be used via HP-IB).

X

and

Y

AXIS outputs and

and

does not require the use

an

x-y recorder. The internal source is used as the

of

an external controller (although this

desired. Its

too

can

1-16

Model

8903B

General Information

lhble

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

period.

1-1.

Specifications

SYSTEM SPECIFICATIONS

(1

of

5)

I------

Characteristic

DISTORTION

Residual Distortion and Noise (the higher 80 kHz BW

500

SIG/NOISE

Frequency Range Display Range

Accuracy

Input Voltage Range Residual Noise (the

higher of)

of):

kHz BW

Performance Limits

-80 dB or

-70

-65 dB or

50

0

f

1

50

-85 dB or

-70

17

pV

dB or

50

pV

50

pV

Hz to 100 kHz to 99.99 dB dB

mV to 300V

17

pV

dB or 50pV

20 Hz to 20

Hz to 50 kHz

50

kHz to 100 kHz

80 kHz BW

500 kHz BW

SOURCE

20

Conditions

kHz

FREQUENCY

Range Resolution Accuracy

OUTPUT

Range Resolution Accuracy

Flatness

Distortion and

Noise (the higher of) Impedance

SlNAD

Fundamental Frequency Range Display Range Accuracy

Input Voltage Range

LEVEL

20 Hz to

0.3% increments

0.3% of setting

0.6 mV to 6V Better than 0.3%

f2%

f3% of setting

f5%

f0.7%

f2.570 (f0.22

-80

-70

-65 dB or 38pV

6000

20 Hz to 100 kHz

0 to 99.99 dB

fl

f2

100

of setting

(f0.06

dB or 15pV dB or 38pV

fl%

dB

50 mV

to

kHz

dB) dB)

or

500

300V

Open circuit

60 mV to 6V; open circuit; 6 mV to

0.6

mV to 6

20

Hz to

20

Hz to

20

Hz to

20

Hz to

50

kHz to

f2%

MEASUREMENT

Front-panel selectable

20 Hz to

20

kHz to

20

Hz to

50

kHz

6V;

open circuit;

rnV;

open circuit;

20

kHz; 1 kHz reference

100

kHz; 1 kHz reference

20

kHz; 80 kHz BW

50

kHz;

500

100

kHz; 500 kHz BW

20

kHz (unfiltered or with low-pass filters)

100

kHz

20

Hz to

kHz BW

(HP-IB)

100

20

Hz to 100 kHz

kHz

Residual Noise and Distortion (the higher of)

rev.

30DEC88

-80 dB

-70

-65 dB or

or

dB or

15

45

pV

pV pV

20

50

Hz to Hz

to

kHz

20

kHz; 80 kHz BW

50 kHz;

to

500

100

kHz; 500 kHz BW

kHz

BW

1-17

General Information Model

8903B

Characteristic

DISTORTION

Fundamental Frequency Range Display Range

Accuracy

Input Voltage Range Residual Noise and Distortion (the

of)

higher

AC LEVEL

Full Range Display

Overrange Accuracy

DC LEVEL

Full Range Display

Overrange

Accuracy

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

lbble

SYSTEM SPECIFICATIONS (Cont'd)

Performance Limits

20

Hz to 100 kHz

0.001% to 100%

0

(-99.99 to

fl

dB

f2

dB

50

mV to 300V

-80 dB or 15

-70

dB or 45

-65 dB or 45

300.0V, 30.00V,

3.000V, .3000V,

30.00 mV,

3.000 mV, .3000 mV 33%

k2Yo

f4% f4'/0

300.0V, 48.00V,

16.00V, 4.00V

33%

fl

.O%

f6 mV

20

Hz to 150 kHz

20 Hz to 100 kHz

5

digits

0.01 Hz

k(0.004Y0

50

mV

5.0 mV

30

f2

3rd order response, 18 dB/octave or 60 dB/decade

80 f4 kHz 3rd order response, 18 dB/octave or

60 dB/decade

dB)

pV

of reading

+1

digit)

kHz

1-1.

Specijitatwns

(2

of

5)

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

kHz to

50

kHz;

500

kHz BW

50

kHz to 100 kHz;

Except on the 300.0V range

50

mV to 300V;

50

mV to 300V;

0.3 mV to 50mV;

Except on the 300.0V range 600 mV to 300V Vin <600 mV

In ac level mode In distortion, SINAD, and signal-to-noise modes Frequencies >lo0 Frequencies 400 Hz

Distortion and SINAD modes only In ac level and signal-to-noise modes only

500

kHz BW

20

Hz to

20

kHz

to

20

Hz to 100 kHz

Hz

20

kHz

100 kHz

-18

rev.

3ODEC88

Model

8903B

General

Information

Characteristic

PLUG-IN AUDIO

400 Hz Highpass Filter

3 dB Cutoff Frequency

Rolloff

CClTT Weighting Filter

Deviation from Ideal

Response:

CClR Weighting Filter Deviation from Ideal Response:

FILTERS

lhble

SYSTEM

Performance

400

f40 Hz

7th order response:

42 dB/octave or

140 dB/decade

jz

0.2 dB

jz

1.0 dB

k

2.0 dB

jz

3.0 dB

f

2.0 dB

f

1.4 dB

rt

1.0

dB

rt

0.85 dB

rt

0.7

dB

f

0.55

dB

f

0.5

dB

f

0.2

dB

f

0.4 dB

f

0.6 dB

f

0.8 dB

f

1.2 dB

f

1.65 dB

f

2.0 dB

+

2.81-inf dB

Limits

1-1.

Specifications

(3

SPECIFICATIONS (Cont'd)

CCllT Recommendation P53

20

to 55OC, 80% relative humidity At 800 Hz 300 Hz to 3 kHz 50

Hz to 300 Hz, 3 kHz to 3.5 kHz

3.5 kHz to

CClR

Recommendation 468-2,

20 to 55OC, 80% relative humidity

31.5 Hz to 63 Hz 63 Hz to 100 Hz

100 Hz to 200 Hz 200 Hz to 400 Hz 400 Hz to 800 Hz

800 Hz to 1 kHz

1 kHz to 6.3 kHz

6.3 kHz to 8 kHz

8

kHz to 9 kHz

9 kHz to 10 kHz

10 kHz to 12.5 kHz

12.5 kHz to

16 kHz to

20 kHz to 31.5 kHz

at 31.5 kHz

of

5)

5

kHz

14

kHz

20 kHz

Conditions

DIN

45405

C-MESSAGE Weighting Filter

Deviation from

Ideal Response:

CCIR/ARM Weighting

Filter

Deviation from

Ideal Response:

rev.30DEC88

f

2.0 dB

f

1.0

f

0.2

f

2.0 dB

f

3.0 dB

f

2.0

f

1.4 dB

f

1.0 dB

f

0.85 dB

f

0.7

f

0.55

f

0.5

f

0.2 dB

dB dB

dB

Per BSTM 41004 20 to 55OC, 80% relative humidity

60 Hz

to

300 Hz

300 Hz to 3 kHz

1

kHz

at 3 kHz to 3.5 kHz

3.5 kHz to 5 kHz

CClR Recommendation 486-2, averaging responding meter,

No.

Dolby Labs bulletin 20 to 55OC, 80% relative humidity

31.5 Hz to 63 Hz 63 Hz to 100 Hz 100 Hz to 200 Hz 200 Hz to 400 Hz 400 Hz to 800 Hz

1

800 Hz to

1 kHz to 6.3 kHz

6.3 kHz to 8 kHz

kHz

19/4.

1-19

General Information

Model

8903B

I

Characteristic

Deviation from

nble

SYSTEM SPECIFICATIONS (Cont'd)

Performance Limits

f

0.4 dB

f

0.6

dB

f

0.8 dB

f

1.2 dB

f

1.65

dB

-f

2.0

dB

+2.8/-inf dB

f

2.5

dB

f

2.0 dB

f

1.5

dB

f

1.0dB

+1.5/-2.0 dB

+1.5/-3.0

+2.0/-4.0 dB

+3.0/-6.0

+3.0/-inf dB

dB

1-1.

Specifications

(4

of

5)

Conditions

8 kHz to 9 kHz 9 kHz to 10

12.5 kHz to 14 kHz

16

20 kHz to 31.5 kHz at 31.5 kHz

IEC Recommendation 179 and ANSI S1.4, type 1 sound level

meter 20 to 55'C, 80% relative humidity

20 25

31.5

50

4

kHz to

6.3

8

kHz to

10

12.5 Hz to

10

kHz

kHz to 12.5 kHz

kHz to 20 kHt

Hz

to 25 Hz

Hz

to

31.5 kHz

Hz to

50

Hz

to 4 kHz

6.3

kHz

kHz to 8 kHz

10

kHz

kHz to 12.5 kHz

26

kHz

Operating Storage

INPUT TYPE

MAXIMUM INPUT

INPUT IMPEDANCE

Resistance

Shunt Capacitance

COMMON MODE REJECTION RATIO

REMOTE OPERATION

POWER REQUIREMENTS

Line Voltage

100,

120, 220,

240 Vac

100,

120 Vac

0"

to 55OC

-55O

to 75OC

Balanced

425V Peak

100

kR

fl%

101 kR

<300

>60

>45

>30 dB

HP-IB STD 488-1 978 Compatibility Code: SH1, AH1,

L3,

PPO, DC1,

pF

dB dB

LEO,

fl%

T5,

SR1,

DT1,

TEO,

RL1,

CO,

El

Full differential

Differentially applied, or between either input and ground.

Except in dc level mode

1

kHz

only

of

x

IEEE

Std. 488-1 978,

10

and

+

10

keys,

In dc level mode Each terminal to ground

20

Hz to 1 kHz, Vin < 2V 20 Hz to 20 Hz to 20 kHz The Hewlett-Packard Interface Bus (HP-IB) is HewlettPackard Company's implementation "Digital Interface for Programmable Instrumentation". All functions except the line switch, the and the low terminal float/ground switches are remotely

controllable.

48 to

66

Hz

48 to 440 Hz

1-20

rev.

30DE

C88

Model

8903B

General Information

Characteristic

POWER DISSIPATION

CONDUCTEDAND RADIATED INTERFERENCE

(EMI)

CONDUCTEDAND RADIATED SUSCEPTIBILITY

NET WEIGHT

DIMENSIONS

(Full

Envelope)

Height Width Depth

nble

SYSTEM SPECIFICATIONS (Cont’d)

~~~

Performance Limits

~~

100-A maximum

MIL STD 461 B

MIL

STD

461 B-1980

12.3 kg (27

16.4 kg (36

146 mm (5.75 in.) 425 mm (16.8 in.) 462 mm (18.2 in.)

Ib)

1-1.

Specifiations

(5

of

5)

Conditions

Conducted and radiated interface is within the

of

requirements

FTZ

and

methods CEO3 and RE02 of MIL STD 461 B

526/527.

Conducted and radiated susceptibility meets the requirements (1 voltlmeter)

methods CSOl , CS02, and

of

MIL STD 461 B dated 1980.

RS03

of

Net

Shipping

Note: For ordering cabinet accessories, the module sizes are

5

1/4H

x

1MW x 170.

rev.30DE

C88

1-21

General Information Model

8903B

lbble

All

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

1-2.

Supplemental

Information

SOURCE

Frequency Switching Speed:

HP-IB programming time).

Sweep Mode:

points/decade or stop frequencies. impedances vs frequency.

Logarithmic sweep with up to

255

Points total between entered start

Output Level Switching Speed:

HP-IB programming time.

<3

ms (does not include

500

20 ms (does not include

Typical Source to Analyzer Isolation (Option

System distortion and noise can be degraded when driving low impedance loads (with source output impedance in the

50R

mode) due to coupling from the source output to the

analyzer input.

See Figure

MEASUREMENT

SINAD

Detection: Resolution:

dB, the display duce digit flickering with noisy signals. (Full resolution is available

16.1

Analog Meter*

ratios Accuracy: 1 dB typical.

Tuning:

quency.

Time to Return First Measurement:

Measurement Rate:

True

rms

or

rms

calibrated average.

0.01

dB for ratios >25 dB. For ratios <25

is

rounded

by

defeating this feature using Special Function

.)

active in SINAD only and for SINAD

518

dB (or

524

notch filter is tuned to analyzer source fre-

to

the nearest half dB to re-

dB using Special Function 7.1).

1.5s

typical.

2.0

readingsls typical.

AC LEVEL

AC Converter:

nals with (crest factor age detection, quasi-peak detection (Meets

standard.)

3

dB Measurement Bandwidth:

Time

to

Measurement Rate:

detectors.

True rms responding detection for sig-

Return First Measurement:

2.5 readings/s for

Quasi-peak Detector Accuracy:

f6%.

DC LEVEL:

Time to Return First Measurement: Measurement Rate:

3

FREQUENCY MEASUREMENT

SIG/NOISE

Resolution: Measurement Rate:

average detectors (one reading/2 seconds for quasipeak detector).

Detection:

peak.

Time

Operation:

input voltages as the internal source is switched on and

Off.

Same as SINAD.

One readinglsecond for rms and

True rms or

of

Return First Measurement:

The Audio Analyzer displays the ratio of the

rms

calibrated average or quasi-

~2.5s typical.

DISTORTION

3

dB Measurement Bandwidth:

Detection:

True rms or rms calibrated average.

10

Hz to

500

kHz

Displayed Resolution:

0.0001%

0.001%

0.01

0.1

Time to Return First Measurement:

Measurement Rate:

(<0.1%

(0.1% to

O/O

(3%

YO

(>30%

The meter has hysteresis. The trip point for the 24dB range

3%

to

30%

distortion)

~~ ~~

distortion)

2 readings/s typical.

1.5s

typical.

Measurement Rate:

lected.

Counting Technique:

AUDIO FILTERS

400

Hz

High-Pass Filter Rejection:

>65

dB at

60

REAR-PANEL INPUTS AND OUTPUTS

Recorder Outputs:

X

Axis: 0 to

cillator frequency.

10

Output Resistance:

Y

Axis:

0 to

10

and entered plot limits

Output Resistance: Pen

Lift:

TIL

Monitor Output:

Output Impedance: In ac level mode, provides scaled output of measured input signal In SINAD, distortion, and distortion level modes, provides scaled output removed.

is

>

18 dB, and the trip pont for the 18-dB range

same as measurement mode

reciprocal with 2 MHz time base.

Hz.

Vdc corresponding to the log of the

1

kR

Vdc corresponding to the displayed value

1

kR

output

600R

of

input signal with the fundamental

1-7

for the plot of various load

of

53),

rms

calibrated aver-

>500

kHz.

~1.5s

rms

(20 Hz

~1.5s

reading/s.

>40

001

only)

CClR

468-3

typical.

and average

to

20

typical.

dB at

240

is

<17 dB.

kHz)

se-

Hz;

os-

1-22

rev.

30DE

C88

Model

8903B

General

Information

Instrument

AC Calibrator

Audio Synthesizer

Computing Controller

DC Standard

Digital Voltmeter

Feedthrough Termination

Frequency Standard

Oscilloscope

Power Supply

Type

lbble

Accuracy: 0.5%, 7 mV to 300V, 20 Hz to 100 kHz Flatness: fO.1%, 20 Hz to 100 kHz, <6V Output Current: 60 mA Frequency Accuracy: f5%

Frequency Range: 20 Hz to 500 kHz Frequency Accuracy: f4ppm Output Range: 0.6 Vrms into 500. Output Attenuation Accuracy: f0.075 dB, to 0.3 mV range

HP-I6 compatibility as defined by IEE std. 488 and the identical ANSl Std. MCl PPO, DCO, DTO, and C1, 2,3,4,5.

Output Range: 3 mV to 300V Accuracy: f0.1% f0.3mV

AC Accuracy: f0.2% at 6 Vrms and 1 kHz DC Accuracy: f0.2% at 1

Impedance: Impedance Accuracy: fl% Maximum Dissipation: 180 mW

Impedance: 600R Impedance Accuracy: Maximum Dissipation: 100 mW

Frequency: 0.1,

Accuracy:

Bandwidth: c3 dB down Sensitivity: 5mV per division minimum Input Impedance: 1 MR Triggering: Internal and External

output: to f15V

fl

500

ppm

1-3.

Recommended

Critical Specifications

.l:

SH1, AH1, T2, TEO,

V

fl

YO

1,

2,

5,

or 10 MHz

0 to

10

MHz

Test

Equipment

L2,

LEO, SRO,

HP 745A and HP 746A, Datron 4200 or

Fluke 5200A and Fluke 521 5A

HP 3336C

HP 9825A/ 98034Al98213A

or

HP 858 Opt.

007 HP 7408 or Datron 4000 or

Fluke 893AR

HP 3455A

HP

11

048C

HP

11

095A

House Standard

HP 174OC

P

-

A

Resistor 1 OOkR Signature

Analyzer

Test Oscillator

I

HP 8904A Multifunction Synthesizer

20 dB Pad

C = Operator’s Checks; P = Performance Tests;

rev.30DEC88

Accuracy: f 0.1% Because the signatures documented are unique to a given signature analyzer type, no substitution of types is

recommended. Frequency:

OUtDUt: 30

Frequency Range: 20Hz to 350 kHz Frequency Accuracy: A4 ppm Output Range: 9V p-p into 50R Flatness: f0.09dB. 20Hz to 350kHz

Attenuation: Frequency Range: 20 Hz to 100 kHz Impedance:

1

kHz

VPD

20

dB (fO.l dB)

5OQ

A

=

Adjustments; T = Troubleshooting

HP0698-7497 HP 5005A

HP 8904A

Texscan FP-50 [20dB]

P

I

1-23

General Information Model

8903B

Accessory’

Digital Test/

Extender Board

Foam Pad

Specifications

No

substitution recommended

44 contacts

30

contacts

Conductive polyurethane foam,

(2

x

22), 3 required

(2

x

15),

2

required

12

x

12

x

0.25 inches (nonmagnetic)

NOTE

The

performance tests, adjustments, and troubkshooting procedures based on the assumption that the recommended test equipment Substituting alternate test equipment

may

require modifiation

procedures.

Suggested

HP 08903-6001 8

HP 08901-60084

HP 08901-60085

HP 4208-0094

Model

are

is

used.

of

some

1-24

rev.30DEC88

Model

8903B

Installation

2-1.

INTRODUCTION

This section provides the information needed pertinent to initial inspection, power requirements, line voltage and fuse selection, power cables, interconnection, mating connectors, operating environment, instrument mounting, storage, and shipment.

In addition, this section also contains the procedure for setting the internal HP-IB talk and listen address switches.

2-2.

INITIAL INSPECTION

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 instrument has been checked mechanically and electrically. Procedures

performance are given in Section

defect, Packard office. If the shipping container is damaged, notify the carrier as well as the Hewlett-Packard office. Keep the shipping materials for the carrier’s inspection.

or

Section

2

INSTALLATION

to

install the Audio Analyzer. Included is information

p7imim-l

To

avoid hazardous electrical shock, there are signs of shipping damage to any portion of the outer enclosure (covers, panels, meters).

4.

If the contents

if the instrument does not pass the electrical performance test, notify the nearest Hewlett-

do

not perform electrical tests when

for

checking electrical

are

incomplete,

or

the cushioning material shows signs of stress,

if

there

is

mechanical damage

or

2-3.

PREPARATION FOR USE

Power Requirements

The Audio Analyzer requires a power source of 100, 120, single phase maximum.

or

[mJ

To

avoid the possibility of hazardous electrical shock,

440

126.5

220,

Hz

single phase. Power consumption is 100

instrument at line voltages greater than

greater than

3.5

mA.

100

or

66

120 Vac,

Hz.

Leakage currents at these line settings may exceed

+5%

to

-lo%,

48

to

do

not operate this

Vac with line frequencies

or

240

Vac,

+5%,

to -lo%,

48

to

66

Hz

VA

2-

1

Installation Model

I\"'NGI

This

is a Safety terminal). mains power source to the product input wiring terminals, power cord,

supplied power cord set. Whenever impaired, the product any unintended operation.

If this instrument is to be energized via an external autotransformer, make sure

pole of the power source.

An

the

autotransformer's common terminal

Line Voltage and Fuse Selection

BEFORE PLUGGING THIS INSTRUMENT into the Mains (line) voltage,

be sure the correct voltage and fuse have been selected.

Class

I

product (that

uninterruptible safety earth ground

must

be made inoperative and be secured against

is,

provided with a protective earth

it

is likely that this protection has been

is

must

be provided from the

or

connected to the earthed

8903B

Verify that the line voltage selection card and the fuse are matched to the power source. Refer to Figure 2-1,

Fast blow fuses may be ordered under

and 2110-0001,

Line Voltage and &e Selection.

HP

part numbers 2110-0043, 1.5A for 100/120 Vac operation

1.OA

for

220/240 Vac operation.

Power Cables

(WARNINGI

BEFORE CONNECTING THIS INSTRUMENT, the protective earth

terminals 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

not be negated by the use

protective conductor (grounding).

This instrument is equipped with a three-wire power cable. When connected to an appropriate

receptacle, this cable grounds the instrument cabinet. The type of power cable plug shipped with each instrument depends on the country of destination. Refer

power cables available.

of

an extension cord (power cable) without a

to

Figure

2-2

for the part numbers of the

must

ac

power

2-2

Model 8903B Installation

HP-I6

Address Selection

This task should be performed only

e

by

service 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

disconnected before attempting to change the

HP-IB

In the Audio Analyzer, the HP-IB talk and listen addresses are selectable by following procedure explains how the switches are to be set. Refer and listen addresses. The address

(In binary, this

is

11100; in decimal

is

factory set for a Talk address

it

is

28.) To change the HP-IB address, the top cover

Analyzer must be removed.

address.

to

Table

of

"\"

an

internal switch. The

2-1

for a listing of the

and a listen address of

of

the Audio

talk

"<"

.

Operating voltage

1.

Open cover door,

2.

Remove the Line Voltage Selection Card. Position the card

Push

3.

Rotate the Fuse

the

cover door.

IS

the card

shown

firmly

Pull

in

pull

into

module

window.

the

FUSE

the

lever to

Figure

PULL

lever and rotate to left. Remove

slot.

its

normal position. Insert a fuse of the correct value

2-1.

Line Voltage and he Selection

To

avoid the possibility

shock,

do

voltages greater than 126.5 Vac with line frequencies greater than 66 at these line settings may exceed 3.5

so

not operate this instrument at line

the

the line voltage appears at top-left cover.

fuse.

of

hazardous electrical

Hz

(leakage currents

mA).

in

the holder. Close

2-3

Installation

Model

8903B

Plug

TLPe

00

250V

\u

8

6

125V

fi

1

oov

(Same plug

@z3

pJ

00

as

250V

E

250V

above)

Cable

HPParf

Number

8120-1351

8120-1703 4 90°/900 90

8120-1369 8120-0696 4 NZSSl98/ASC112' 80

81 20-1 689 7 STR/STR' 79 8120-1692 2 STR/90° 79

81 20-1 378 8120-1521 6 STR/90° 80

8120-1751

8120-4753 2 STR/STR 90 81 20-4754 3 STR/90° 90

81 20-21 04 3 STR/STR SEVl 01

8120-2296 4 STR/90° 79 8120-3997 4 STR/90° 177

81 20-0698 6 STR/STR NEMAG-15P 90

0

90°/STR BS1363A' 90

0

STR/STR 79

STR/90°

1

STR/STR NEMA51

1

STR/STR 90

1959-24507 Type 12

Plug

Description

5P'

1

cable

Length

(inches)

80

79

Mint Gray

Jade Gray

Gray Gray

Black

I

Rhodesia,

Singapore

Austrailia,

New Zealand

East and West Europe, Saudi

~ Arabia, Egypt,

(unpolarized in

many nations)

United States, Canada, Mexico, Phillipines, Taiwan

U

.S./Canada

Switzerland

United States,

Canada

I

2-4

250V

0

8

fi

Part number shown

cable including plug.

8120-2956 8120-2957 4 90°/900 8120-3997 4 STR/STR

8120-421 1 7 STR/STR'IEC83-81 79 8120-4600

81 20-1 860 6 STR/STR'CEE22-V1 59

8120-1575 0 STR/STR 31

8120-2191 8 STR/90° 8120-4379 8 90°/900 80

for plug

E = Earth Ground;

Figure

3

90°/STR 79

8

STR/90° 79

(Systems Cabinet Use)

59

IS

industry identifier for plug only. Number shown for cable

L

=

Line; N = Neutral;

2-2.

Power Cable and Mains Plug

STR

=

Straight

Gray

Black

I

Jade Gray

Jade Gray Jade Gray

I

Jade Gray

is

HP

Part Number for complete

Part

Numbers

Denmark

I

South Africa, India

1

Model 8903B Installation

To set the

1.

2.

3.

4.

5.

6.

HP-IB

Disconnect the line (Mains) power cable. Remove any HP-IB cables Remove the Audio Analyzer top cover.

a. Remove the

screw within each foot.

b. Unscrew the Pozidriv screw at the center of the rear edge of the top cover. This

screw and will cause the top cover

c. Lift

d. Locate the HP-IB address switch accessible through a hole near the center rear of the internal

shield cover.

Use a pencil (LON) condition. The switch with a circuit board places it in Only setting will override. Analyzer will output one byte (the defeats HP-IB operation.)

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

the HP-IB connector.

Address on the Audio Analyzer:

or

connectors from the HP-IB connector.

two

plastic feet from the rear of the

off

the top cover.

to

set the switches to the desired HP-IB address and Talk Only (TON) or Listen Only

is

illustrated in Figure

“5”)

is

the most significant address bit

its

“1”

If

the address switches and the TON switch are

position.

status

top

cover by removing the panhead Pozidriv

to

pull away from the front frame.

2-3.

Facing the board, the left hand switch

(A5

in Table

If

the TON and LON switches are both set

byte) each measurement cycle. (Setting

2-1).

Setting a switch toward the printed

all

set

to

“l”,

all

switches

HP-IB

is

a captive

(marked

“l”,

the Talk

the Audio

cable

to

“1”

to

7.

To confirm the setting, refer this manual.

to

HP-IB Address in the

Interconnections

Interconnection data for the Hewlett-Packard Interface Bus

Mating Connectors

Interface Connector.

screws are metric.

Coaxial Connectors.

BNC male connectors.

The HP-IB mating connector is shown in Figure

Coaxial mating connectors used with the Audio Analyzer should be the

Detailed Operating

is

provided in Figure

Instructions

2-4.

Note that

in Section 3 of

two

securing

50R

2-5

Installation Model

8903B

Figure

The Address Shown is

2-4.

OPERATING ENVIRONMENT

The operating environment should be within the following limitations: Temperature

Humidity Altitude..

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

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

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

Bench Operation

The instrument cabinet has plastic feet and foldaway tilt

(The plastic feet are shaped to ensure self aligning

raise the front

of

the instrument for easier viewing

Rack Mounting

The Audio Analyzer exercised when lifting to avoid personal injury. Use equipment slides when rack mounting.

2-3.

HP-IB Address Switch Shown

11

100

in

Binary with Both Talk Only and Listen Only

is

heavy for its size

as

Set

by

the Factory.

<95%

<4570

stands

of

the instruments when stacked.) The tilt

of

the front panel.

(12.3

for convenience in bench operation.

kg,

27

lb). Care

meters

must

be

Off.

0"

(15

to

+55"C

relative

000

feet)

stands

2-6

DO

NOT

BLOCK instrument does not use a cooling fan, it is important that good ventilation be provided. Allow

the ventilation holes in the bottom panel. Since this

for

1

to 2 inches clearance around the bottom panel.

Model

8903B

lbble

2-1.

Allowable

HP-IB

Address Codes

Installation

I

Address Switches

A5

A4 A3 A2 A1

00000

00001 00010 00011 00100 00101 00110 00111 01000 01001

0[11011101

01100 01101 01110 01111

10000 10001

C

I

1]0]0

11011

I

1

0 0

I

10101

10110

I

Talk listen Decimal Address Address EquivaChar- Char- lent acter acter

@

A B

C

D

E

F

I

SP

!

,

#

$

%

&

G

I

~ ~~

1

H

I

J

L

M

N

0

P

Q

S

T

U

V

(

1

-

I

0

1

I

3

4 20 5

6

i

0

1

2

3 4

5

6

~~ ~

7

8

9

~~

10

12

13

14 15

16 17

I

-

I

19

21

22

Rack mounting information

as

the instrument paragraph

1-13,

options, they may be ordered through the nearest Hewlett-Packard office. Refer to

Mechanical

0

1

111 111

0

11010 11011 11100

11101 11110

is

provided with the rack mounting kits.

Options,

in Section

X

Y

Z

I

\

1

n

1.

8 9

<

- -

>

24

25

26

27

28 29 30

If

the kits were not ordered with

2-7

Installation

2-5.

STORAGE

Environment

AND SHIPMENT

Model

8903B

The instrument should be stored in a clean,

to

apply

Temperature Humidity

Altitude..

both storage and shipment:

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

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

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

dry

environmer-_. The following environmental limitations

Packaging

Original Packaging.

through Hewlett-Packard offices. please fill out one of the blue tags located required, return address, model number, and full serial number and attach the container “FRAGILE” by model number and full serial number.

Other

cially available materials:

Packaging.

1.

Wrap the instrument in heavy paper center, complete one of the blue tags mentioned above and attach

2.

Use a strong shipping container. A doublewall carton made adequate.

3.

Use enough shock-absorbing material instrument to provide a panel with cardboard.

Containers and materials identical to those used in factory packaging are available

If

the instrument is being returned

at

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

to

assure careful handling. In any correspondence refer

The following general instructions should be used for re-packaging with commer-

or

plastic.

(75

firm

cushion and prevent movement in the container. Protect the front

to

(If

shipping

100

mm layer; 3 to 4 inches) around

15

300

to

Hewlett-Packard for servicing,

it

to

the instrument. Mark

to

a

Hewlett-Packard office

it

to

the instrument.)

of

1.9

MPa

(275

-55°C

meters

to

psi) test material is

to

+75”C

<95%

the instrument

(50

all

relative

000

or

service

sides of

feet)

4.

Seal the shipping container securely.

5.

Mark the shipping container “FRAGILE”

to

assure careful handling.

2-8

Model

8903B

Installation

SIGNAL GROUND

REN

DIO

DIO DIO DIO

11

10

9 8

7

6

8 7

6

5

SHOULD BE GROUNDED NEAR TERMINATION

OF

OTHER WIRE

TWISTED PAIR

OF

P/O TWISTED PAIR WITH P/O TWISTED PAIR WITH

P/O TWISTED PAIR WITH

P/O TWISTED PAIR WITH P/O TWISTED PAIR WITH P/O TWISTED PAIR WITH

ISOMETRIC

THREAD

-

M3.5 x 0.6

Logic Levels

The Hewlett-Packard Interface Bus logic levels are

0.0 Vdc

Programming and

to

+0.4 Vdc and the false (0) state is 2.5 Vdc to

Output

Data Format

SHIELD -CONNECT TO ATN EARTH

SRQ

IFC NDAC

NRFD

DAV

EO1 DIO DIO DIO DIO

24-PIN MICRO-RIBBON (SERIES

TTL

compatible, that is, the true (1) state is

+5

Vdc.

4

3

2

1

GROUND

57)

CONNECTOR

Refer to Section 3, “Operation”.

Mating Connector

HP

1251 -0293; Amphenol 57-30240.

Mating Cables Available

HP 10631A, 1 meter (3.3 HP 10631C, 4 meters (13.2

ft),

HP 10631B, 2 meters (6.6

ft),

HP 10631

D,

0.5

ft)

meters (1.6

ft)

Cabling Restrictions

1. A Hewlett-Packard Interface Bus system may contain no more than 2 meters (6.6 connecting cable per instrument.

2. The maximum accumulative length of connecting cable

system is 20 meters (65.6

~

Figure

ft).

2-4.

Hewlett-Packard Interface

for

any Hewlett-Packard Interface Bus

Bus

Connection

ft)

of

2-9

Model

8903B

Operation

3-1.

INTRODUCTION

General

This section provides complete operating information for the Audio Analyzer. Included in this section are descriptions of all front- and rear-panel controls, connectors, and indicators, remote and local operator's checks, operating instructions, and operator's maintenance.

Operating Characteristics

Table

3-1

briefly summarizes the major operating characteristics of the Audio Analyzer. The table not intended to be an in-depth listing of all operations and ranges but gives an idea of the instrument's capabilities. Section

HP-IB

For

1;

Table

capabilities, refer to the summary contained in Table

Turn-On Procedure

Section

3

OPERATION

more information on the Audio Analyzer capabilities, refer

1-1,

Specifications;

and Table

1-2,

Supplemental Information.

3-3,

Message Reference Table.

to

the description in

For

information on

is

Befor

extension cords, auto-transformers, and devices connected to connected earth grounding will cause a potential shock hazard that could result

personal

the unit under test and the Audio Analyzer prior to energizing either unit.

For

250V

circuited fuseholders.

Before the Audio Analyzer is switched on,

the power source,

Do

to be greater than

instrument may result.

the Audi

to

injury.

continued protection against fire hazard, replace the line fuse with a

fast blow fuse

not allow the voltage at the

Analyzer is switched on, all protective earth terminals,

it

should be

a protective earth socket. Any interruption of the protective

in

In addition, verify that a common ground exists between

of

the same rating.

or

damage

+1OV

or

to

the instrument may result.

SOURCE

less than

Do

not use repaired fuses

it

must be set to the voltage of

OUTPUT HIGH

-1OV

(ac + dc)

or

LOW

or

damage

or

short

terminal

to

the

3-1

Operation Model 8903B

If

the Audio Analyzer is already plugged in, set the LINE switch to ON.

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

are given under Operator's Maintenance.

3.

Plug in the power cable.

4.

Set the LINE switch to ON.

NOTE

If

the power cable

2-1).

is

not

F'use Ratings

When the

LINE

switch is set to

ON,

all front-panel indicators will light

for

approximately 4 seconds after which the instrument is ready to be operated.

Local

Operation

Information covering front-panel operation of the Audio Analyzer below. To rapidly learn the operation of the instrument, begin with Simplified Operation and Operator's Checks. Once familiar with the general operation of the instrument, use the Detailed Operating Instructions for in-depth and complete information on operating the Audio Analyzer.

Simplified Operation.

the Audio Analyzer.

not an exhaustive listing of all Audio Analyzer functions. However, an index to the Detailed Operating Instructions appears in Table 3-2 to guide the operator to the more complete discussion of the topic

of interest.

Panel Features.

3-1.

Figure the rear panel.) Rear-panel features are shown in Figure for rear-panel signal levels and

Detailed Operating Instructions.

reference for the Audio Analyzer user. The instructions 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 controls, inputs, and outputs, (for example, Amplitude, Monitor, etc.). Also included are instructions for using the many User Special Functions

etc.).

The Detailed Operating Instructions are indexed by function in Table

(For Option

Simplified Operation provides a quick introduction

It

is designed to rapidly orient the new user with basic procedures and therefore is

F'ront-panel controls, indicators, and connectors are illustrated and described in

001,

the INPUT and OUTPUT HIGH and

3-2.

This figure provides a good quick reference

also

includes the impedance

The Detailed Operating Instructions provide the complete operating

(for

example, Hold Settings,

at

is

given in the sections described

to

front-panel operation of

LOW

connectors are located on

the rear-panel connections.

Error

Disable, Special Functions,

3-2.

of

nearly all

3-2

Each section contains a general description which covers signal levels, ranges, and other general information. 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 Audio Analyzer

At

uses to make the measurement. away from measurement pitfalls and to help get the most out of the Audio Analyzer. Also included references to other sections which contain related information. The Detailed Operating Instructions are designed needed to apply the instrument to the task at hand.

so

that both casual and sophisticated users can rapidly find at one location all the information

the end of each discussion are comments intended

to

guide the user

are

Model

8903B

Operation

Operating Information Pull-Out Cards.

to

reference sheets attached a

complete listing of HP-IB codes and Functions. The cards are intended of front-panel operation.

Supplemental Information.

pertinent to the operating of the Audio Analyzer this manual. what the Audio Analyzer in the Detailed Operating Instructions and provides a basis for applying the Audio Analyzer measurement situations.

It

is intended

mathematical analysis.

Remote

Operation

The Audio Analyzer Instructions pertinent operation including capabilities, addressing, input and output formats, the status byte, and service requests.

In addition

other locations. Address setting output formats appear on one of the Operating Information pull-out cards, and numerous examples of program strings appear throughout the Operation above.

Principles

to

provide an intuitive understanding of audio measurements rather than an in-depth

e

is

At

the end of the discussion is a complete

to

the section described above, information concerning remote operation appears in several

the Audio Analyzer by a tray located below the front-panel. They contain

to

In addition to the information described above several other discussions

of

Operation

is

and how

Basics

capable

to

HP-lB

of

Audio Measurements

of

remote operation visa the Hewlett-Packard Interface Bus (HP-IB).

operation cover

is

discussed in Section

The Operating Information pull-out cards are flexible plastic

data

and error output formats, Error codes, and User Special

be a reference for the user who already

to

its

fullest capabilities are contained in Section 1 of

for

a Simplijied

it

works. This information supplements the block diagrams given

Detailed Operating Instructions

Block

Diagram

is a general discussion of audio measurements.

all

considerations and instructions specific

summary

2

of all codes and formats.

Installation.

has

a basic understanding

is

a

fundamental description of

A

summary

of HP-IB codes and

described under Local

to

various

to

remote

3-2.

OPERATOR’S

CHECKS

Operator’s checks are procedures designed functions.

Basic Functional Checks.

assumes that most front-panel controlled functions are being properly executed by the Audio Analyzer.

HP-IB Functional Checks.

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 performing the Basic Functional Checks). The procedures check all

Two

procedures are provided

of

the applicable bus messages summarized in Table

This procedure requires an oscilloscope and interconnecting cables. It

This series

to

verify the proper operation of the Audio Analyzer’s

as

described below.

of

procedures require an HP-IB compatible computing

3-3.

main

3-3

Operation Model

Operator's Maintenance

(WAR"GI

For

continued protection against fire hazard, replace the line fuse with a

250V

fast blow fuse of the same rating only.

short-circuited fuseholders.

The only maintenance the operator should normally perform is the replacement of the primary power fuse located within the Line Power Module (A14). Figure 2-1, steps 1 and

3.

For

Do

not use repaired fuses

instructions on how

or

to

change the fuse, refer

8903B

to

Fuses may be ordered by looking up the reference designator ordering the correct part number for 100/120 Vac fast

blow).

If the instrument does not operate properly and Hewlett-Packard

located at the end

Paragraph

2-7

in Section

for

service, please complete one of the blue repair tags

of

this manual and attach

2

for

or

for 220/240 Vac operation (both fuses are 250V

NOTE

it

packaging instructions.

F1

in

Section

is

to the instrument. Refer

6,

Replaceable

being returned

to

Parts,

and

3-4

Model

8903B

lhble

3-1.

Operating Characteristics Summary

Operation

Operating Parameter

Output Limits

Input

Limits

Measurements (including counter frequency measurements except in

DC Level)

Detection

Capabilities

~~~

Frequency: Level:

20

Hz to

100

0.6

mV to 6V (open circuit).

kHz

Impedance: 50R or 6000 selectable, floating output can be selected.

Frequency: Level: Impedance:

20

Hz to

x0

to 300V ac or dc.

100

kfl (except dc level);

100

kHz

(150

kHz, ac level)

101

kR (dc level); floating input can

be selected.

AC Level:

~0

to 300 Vac;

20

Hz to

150

kHz.

Full

range display from

.3000 mV to 300.0V in seven ranges.

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.

SlNAD meter marked for EIA and CEPT readings. SIG/NOISE:

99.99 DISTN:

dB.

50

mV to 300V;

50

mV to 300V;

50

Hz to

100

kHz. Display range 0 to

20

Hz to 100 kHz. Display range

-99.99

to 0 dB

DISTN LEVEL: Similar to ac level except that the notch filter is used in the measurement

~ ~~~ ~~ ~ ~ ~

True rms, average detection, or Quasi-Peak (output Detector only).

Swept

Measurements

Audio Filters

Manual Operation

Remote Operation

All

measurements can be swept and frequency vs. measurement result

can be plotted using an external

HP/BP Filter - Up to HIGH PASS

400

Hz:

two

of the following HP/BP filters may be installed:

400

f40

X-Y

recorder.

Hz (3 dB cutoff) CCllT Weighting: CCllT Recommendation P53. CClR Weighting: CClR

C-MESSAGE:

BSTM

A-Weighting: ANSI CCIR/ARM Weighting: CClR

468-2

#41009

S1.4,

FIG

IEC rec

468-2,

1

179

Dolby Labs

LP FILTER

Low PASS

30 kHz:

80

kHz:

30f2

kHz (3 dB cutoff).

80 f4

kHz (3 dB cutoff).

~~~

~

Output level and frequency, input attenuation, ratio, log/linear, display

resolution, measurement selection, and many other operations can be

manually controlled.

All

Audio Analyzer operations except the LINE switch,

switches, and the

+lO

and

x

10

FREQ/AMPT ADJUST keys can be

two

FLOAT

controlled via the Hewlett-Packard Interface Bus.

3-5

Operation Model

3-3.

FRONT-PANEL FEATURES

~ ~

~~

8903B

3

31

30

29

28'

6

27

///I

26 25 24 23

Figure

/I

3-1.

7 8 9 10 11 12 13 14 1 2 45

22 21 20 19

Bont-Panel Features

\

\\

\

18

15

\

16

17

1.

HP-IB

Annunciators indicate remote operation status.

2.

LCL

(local) key returns the Audio Analyzer to keyboard control from remote

3.

START

sweep.

4.

FREQ

of

5.

AMPTD

of the source.

6.

The codes,

7.

Frequency Display Annunciators

8.

MEASUREMENT CYCLE

9.

Unit keys

10.

AUTOMATIC OPERATION

automatically range as appropriate).

11.

Measurement Display Annunciators

12.

RATIO

13.

LOG/LIN

and

STOP FREQ

and

FREQ INCR

the source.

and

AMPTD

two

Numeric Displays

or

instrument

select units and complete manual

key causes measurements to be displayed in

key causes results

keys display

INCR

keys display

show the frequency, measurement results, numeric key entries, error

or

Special Function status.

indicator blinks after each measurement cycle.

key switches instrument

to

or

initiate entry of the

or

initiate entry of the frequency and frequency increment

or

initiate

indicate the frequency units.

entry of the amplitude

data

entry.

to

indicate the measurement result units.

%

or

be displayed in logarithmic

(HP-IB)

start

and stop frequencies of the

or

amplitude increment

automatic &e., functions allowed

dB

relative

or

linear units.

to

a reference.

control.

to

3-6

Model

8903B

14.

15.

16.

17.

18.

19.

20.

21.

22.

MEASUREMENT

keys command the Audio Analyzer

to

make and display the selected measure-

ment.

SINAD

meter

is

marked for

EIA

and CEPT sensitivity and selectivity readings (when within

limits).

INPUT FLOAT LOW PASS RIGHT-MOST OPTIONAL PLUG-IN FILTER

filter slot. The CCITT WEIGHTING (band pass) FILTER (Option according

LEFT-MOST OPTIONAL PLUG-IN FILTER

slot. The

SPCL

couples measurement signal into the instrument.

switch provides floating input when required.

30

kHz and

to

CCITT recommendation

80

kHz filters reject high frequency noise.

key selects the filter that

P53.

is

installed in the right-most

051)

weights receiver testing

key selects the filter installed in the left-most filter

400

Hz HIGH

PASS

filter (option

010)

rejects line related noise and squelch tones.

key completes entry of Special Function codes for accessing instrument operations

additional to those having dedicated front-panel keys. Also permits reading

or

hardware status.

CLEAR

key erases keyboard entries in progress. In remote hold, CLEAR initiates a Trigger with

Settling measurement cycle.

Operation

of

Special Function

23.

Numeric

selection

24.

OPERATING INFORMATION

keys are used for manual entry of frequency, amplitude, limits, RATIO references, and

of

Special Functions.

Function, HP-IB, and error codes.

25.

FREQ/AMPTD ADJUST

x

10

and

+lo

key initiates

26.

The

SWEEP

keys change the source frequency

keys modify the specified increment.

or

settings.

27.

PLOT LIMIT

28.

LINE

switch applies power

29.

FLOAT

30.

SOURCE OUTPUT

31.

IMPEDANCE

key displays

switch provides floating output when required.

provide

light indicates

pullout cards are quick operating references that list Special

or

amplitude in specified increments.

restarts a logarithmic sweep between the

or

initiates entry

to

the Audio Analyzer when set

0.6

mV to

500

source output impedance

of

plotter limits.

6V

(open circuit),

20

to

Hz

if

ON.

lit,

to

600R

START

100

kHz signal. when

and

off.

STOP

FREQ

3-7

Operation Model

8903B

SIMPLIFIED

OPERATION

SOURCE FREQUENCY AND AMPLITUDE

Frequency

To

set source frequency

press:

Amplitude:

To

press:

Frequency Increment

To

Amplitude Increment

To

@

I5j

set source amplitude to

@

13)

set frequency increment step to

set amplitude increment step to

to

[.1

[F)

500

I.]

3V,

.

Hz,

10

200

.

Hz,

mV,

Stepping Increments

MEASUREMENT

For ac level,

I

For dc level, signal-to-noise, or distortion level measurements,

FILTERS

HP/BP

To

step frequency up

press:

up

slowly in

press:

10

SINAD,

AC

I.ll'lormPJo,BPJ

S

@)

10

Hz

(as

set above),

(holding

Hz

steps).

or distortion measurements,

DC

LEVEL

a

'

down causes frequency to move

SIG/

NOISE LEVEL

5

Filter

To

activate any of the optional plug-in filters, press:

DISTN

CORRESPONDING

FILTER

[.I

3-8

LP

Filter

To

activate the

LOW

PASS

30

kHz

filter,

press:

LOW

30 kHZ

I.1

PASS

__

Model

8903B

SWEEP

Start Frequency

To

press:

Stop

Frequency

To

Starting

To

RATIO

set the start frequency

Is:R:RDT]

II]

set the stop frequency of the sweep to

the

Sweep

start the frequency sweep, press:

and

LOG/LIN

I.1

of

the sweep to

.

SWEEP

I.1

100

10

Hz,

kHz,

.

press:

Io)

Operation

-

.

RATIO

To

set the displayed measurement

LOG/LIN

To

convert from linear to logarithmic (or from logarithmic to linear) measurement units,

AC LEVEL DC LEVEL SINAD

SIG/NOISE

DISTN DISTN LEVEL

Measurement

Mode

Duringpower up, the Audio Analyzer is initialized and set to AUTOMATIC OPERATION.

LIN

9%

5%

5% 5%

5%

as

the ratio reference, press:

RATIO

on

LOG

dB

dB dB

dB

NOTE

r.7

RATIO

.

RATIO

LI N LOG

V

or

mV

V

or

mV dBm

9% 9%

5%

V

or

mV

off

dBm

into 6000

into

6000

dB

into 6000

NOTE

Some delilys may be noted when pressing keys during sweeps with an x-y

recorder enabled. These delays allow the pen to lift before moving. However, the keys are recognized and

the

waiting for

Audio Analyzer to respond.

it

is

unnecessary to hold

them

down while

3-9

Operation

Model

8903B

Table

3.2

.

Detailed Operating Instruction Table

of

Contents (functional Listing)

r

Section Page Section Page

Source

Amplitude Display Source Setting Frequency

Increment

Output Impedance

Measurements

AC Level

Common Mode DC Level Detector Selection Distortion Distortion Level Signal-to-Nosie SINAD

Filters

Filters (Low.Pass. High.Pass.

Bandpass)

Notch Tune

Post-Notch Detector Filtering

Sweep and

Plot Limit Sweep Sweep Resolution Time Between Measurements

X-Y

Data Manipulation

Display Level is Watts

Hold Decimal Point

RATIO and LOG/LIN

Errors

Error Disable Error Message Summary

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

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

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

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

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

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

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

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

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

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

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

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

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

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

X-Y

Recording

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

....................................... 3.130

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

Recording

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

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

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

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

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

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

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

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

3-44

3.57 3-74

3.83

3.95

3.42

3.47

3.50

3.53 3-58 3-60

3-118 3-120

3-68 3-93

3-100

3-98

3.133

3.136 3-137

3.55 3-76

3.111

3.62

3.64

Inputs and Outputs

Float

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

Monitor

X-Y

Special Functions

Detector Selection ....................... 3-53

Display Level in Watts Display Source Setting

Error Disable

Hod Decimal Point Hold Settings HP-IB Address Input Level Range (DC Level)

Input Level Range

(Except

Notch Tune Post-Notch Detector Filtering Post Notch Gain Read Display to HP-IB Service Request Condition Special Functions Sweep Resolution Time Between Measurements

H

P-l

HP-IB Address Rapid Frequency Count Service Reques Condition Rapid Source Read Display to HP-IB

Miscellaneous

Automatic Operation

Default Conditions and Power up

Sequence

Float

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

Recording

DC

B

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

A2

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

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

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

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

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

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

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

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

Level)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

3-72 3-90

3.137

3.55 3-57

3-62

3.76

3.78

3.80 3-86

3.88

3.93

3-1

00

3-102

3.114

3.116

3.123

3.133

3.136

3.80

3.104

3.116

3.107

3.114

3-46

3-52 3-72

I

3-10

The detailed operating instructions are arranged in alphabetical order at the

d

Do

not apply more than

300

Vrms to the

INPUT

.

end

of

the

Operation section

.

rev.15MAY88

Model 8903B Operation

3-4.

REAR-PANEL FEATURES

1

8

2

3

7

4

Figure

3-2.

Rear Panel Features

5

6

1.

HP-18

Connector.

connects the Audio Analyzer

to

Hewlett-Packard Interface Bus for remote

operations. when in remote mode, the front-panel REMOTE annunciator lights.

2.

MONITOR.

SINAD,

with the fundamental removed. Output impedance

3.

X AXIS.

start to the stop frequencies. The Output impedance is

4.

Y

AXIS.

limit of the plot. The lower limit equals

1

kR.

5.

Fuse.

6.

Line Power Module.

window indicates nominal line voltage

In ac level mode, provides a scaled voltage output representing the input signal. In

distortion, and distortion level modes, provides a scaled voltage output of the input

is

6000.

A

scaled voltage output representing the log of the oscillator frequency range from the

start

frequency equals

1

kR.

A

scaled voltage output representing the amplitude range from the lower

OV.

The upper limits equals

1.5A

rating

for

100/120

permits operation from

Vac.

LOA

rating for

100,

to

which instrument must be connected (see Figure

OV

220/240

120, 220,

and the stop frequency equals

1OV.

Vac.

or

240

Vac. The number visible in

Center conductor is safety earth ground.

7.

PEN LIFT.

TTL compatible output that

is

used for pen control. TTL high signal

pen.

8.

Serial Number Plate.

instrument configuration. The last five digits form the suffix that

First four numbers and letter comprise the prefix that denotes the

is

unique to each instrument.

signal

1OV.

to

the upper

Output impedance

2-1).

is

used to lift

is

3-11

Operation Model

3-5.

BASIC FUNCTIONAL CHECKS

Description

8903B

Using only an oscilloscope, the overall operation of the Audio Analyzer

89038

AUDIO

OUTPUT

Figure

ANALYZER

MON

I

TOR

OUTPUT VERTICAL

3-3.

Basic

I

finctional

Equipment

Oscilloscope

. . .

. .

. . . . . . . .

. . . . . .

. . .

. . . . . . . . .

.

. . . . . . .

. . .

PROCEDURE

Preliminary Check

OSClLLOSCOPE 89038 OSClLLOSCOPE

lo

I

~ ~

Checks

.

. .

. . . . . . . . .

is

INPUT

Setup

verified.

. .

. . . .

I

. . .

. . . .

. . .

HP 1740A

1.

Remove any cables from the Audio Analyzer’s INPUT OFF, then back 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 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

80

kHz key lights should light.

3.

Connect a BNC-to-BNC cable between the HIGH OUTPUT and the HIGH INPUT. See Figure in 47.1 then pressing the SPCL button. The SPCL key light should be lit.

4.

Connect the oscilloscope

3-3.

to

ON and note that the front-panel

Set both FLOAT switches

to

the MONITOR output on the rear panel. See Figure

AC Level and Output Level Check

5.

Press AMPTD. While the key

6.

Press 1 and V to set the amplitude to 1 Vrms. The left display should show between 1040 Hz (the frequency the source is set to during power up). The right display should show

0.960

between approximately 7 Vpp.

7.

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

and 1.040V. The oscilloscope should show a 1 kHz

is

to

pressed,

or

OUTPUT. Set the LINE switch

LED

annunciators, display segments and

0.000

kHz

and the right display should

the grounded position. Set impedance

0.00

mV should show in the right display.

(1

ms period) sine wave of

to

50R

3-3.

100%.

to

PASS

by keying

960

and

3-12

Basic Functional Checks

rev.04OCT88

Model

8903B

Operation

NOTE

In this and the following steps, the displays may

vary

a few least-significant

digits.

8.

Key in

should remain lit. The right display should remain at approximately

9.

Key in

600R

The right display should drop by approximately

10.

Set the impedance back to 50Rby keying in FLOAT switch to FLOAT. Move the cable from the HIGH OUTPUT Short out the HIGH OUTPUT connector (inner conductor should show approximately

11.

Remove the short from the HIGH OUTPUT, reconnect the HIGH INPUT OUTPUT, and set the OUTPUT switch

12.

Move the cable from the HIGH INPUT to the LOW INPUT. Set the INPUT switch The right display should show

13.

Reconnect the HIGH OUTPUT to the HIGH INPUT

position. Press LOW

14.

Press the STOP FREQ key. While the key (the stop frequency setting at power up).

5.2

SPCL to measure ac level with the average-responding detector. The SPCL key light

100%.

5.0

SPCL to measure ac level again with the rms-responding detector. Set impedance by

by keying in

47.0

then pressing the SPCL button. The SPCL key light should extinguish.

0.6%

(down

to

approximately

47.1

then pressing the SPCL button. Set the OUTPUT

to

the LOW OUTPUT.

to

outer conductor). The right display

95%.

to

the ground position.

100%.

and

set the INPUT switch

PASS

80

kHz. Verify that the

is

LOW

PASS

pressed, the left display should show

80

kHz key light goes

99.4%).

to

the HIGH

to

the ground

20.000

FLOAT.

off.

kHz

Filter

15.

Press

100

kHz.

The left display should show between

16.

Press SWEEP. During the sweep, the SWEEP key light should light. The source frequency sweeps, starting from approximately should show between

96

and

20

Hz and stopping

104%

throughout the entire sweep.

99.70

and

at

approximately

100.30

100

kHz.

The right display

Check

17.

Press the LOG/LIN key. The right display should read approximately

18.

Press LOW

19.

Use the numeric approximately

72

and

20.

Press LOW level) should show between

21.

Press LOW PASS

22.

If

the instrument has Option HIGH-PASS key light should light. Adjust the frequency of the source (to approximately until the right display reads

23.

Press the filter key listed in the following tables for the filter options installed in the instrument. The respective key light should light. For each filter, set the source frequency table. Verify that the level ratio shown in the right display is within the limits shown frequency.

PASS

80

kHz.

data

and units keys to set frequency (but not the level) of the source

80

kHz) until the right display reads

88

kHz.

PASS

30

kHz. The

of

the source (to approximately

26

and

34

30

kHz again to turn it

010

-3

dB.

The left display should show between

30

kHz key light should light. Adjust the frequency (but not the

30

kHz) until the right display reads

kHz.

off.

or

050

installed, press the

dB.

The left display should show between

400

Hz

0.00

HIGH

dB.

-3

dJ3.

PASS

360

The left display

key. The

and

440

as

shown in the

400

Hz.

for

(to

Hz

Hz)

each

rev.

04

OCT88

Basic Functional Checks

3-13

Operation

Table

for

CCITT Weighting Filter (Option 011

or

051)

Model

8903B

Table

I

Oscillator

300 800 000

3 3

500

5 000

(Hz)

Frequency

for

CCIR Weighting Filter (Option 012 or 052)

Oscillator

Frequency

10

20

31.5

200 6 300 7 100

000

(Hz)

1

RATIO

Limits (dB)

-12.1

to

-9.1

to

+0.4

-4.1

-5.5

-0.4

-7.1

-11.5

-40.0 to -32.0

RAT^

Limits (dB)

-31.4

to

-28.4

to -13.1

-14.5

to to to to

+12.4 +12.3

+8.7

-20.7

+12.0 +11.7

+7.5

-23.7

Table

for

C-Message Weighting Filter (Option 013

~ ~

-~

Oscillator RATIO

Frequency

for

CCIRIARM Weighting Filter (Option 014

1

3 5

100

500

000

(Hz)

~~

I

Oscillator

Frequency

20

200

6 300

7

100

10

000

(Hz)

31.5

Limits (dB)

-44.0

to

-9.0

-0.2

to

-4.0

to

-30.0

to

RATIO

limits (dB)

-37.0

to to

-20.1 +6.4

to

+6.1 to +6.7 +1.9

to

-29.3

to

-41.0

-6.0 +0.2

-1.0

-27.0

-34.0

-18.7 +6.8

+3.1

-26.3

or

053)

054)

3-14

Model

8903B

Table

for

“A”

Weighting Filter (Option

015

or

Operation

055)

Distortion Check

24.

Set

all

filters on the Audio Analyzer

key light should light.

25.

Set the source frequency

SINAD Check

26.

Press

SINAD.

27.

Key in should show between display.

6.1

Oscillator

Frequency

10 20 000

to

(Hz)

50

200

000

1

2

000

off.

Press LOW

1

kHz. The right display should show

RATIO

Limits

(dB)

-30.9 to -29.5

to

to -7.8

PASS

-1 0.3 +0.2

+1.9

-1.8

80

-1 1.7

-0.2

+0.5

-3.2

-10.8

Wz.

Press

0.01%

The SINAD key light should light. The right display should show

SPCL

to

hold the notch

12

and

19

filter.

Set the source frequency

dB.

The SINAD meter should read within

to

890

DISTN. The DISTN

or

less.

80

dB

or more.

Hz.

The right display

fl

dB

of the right

Signal-to-Noise Ratio Check

28.

Press AUTOMATIC OPERATION. Press S (Shift) SIG/NOISE. The right display should show

85

dB

or more.

Sweep, X Axis, Y Axis, Pen Lift, and DC Level Check

29.

Disconnect the cable from the OUTPUT and reconnect

panel.

30.

Press S (Shift) DC LEVEL.

31.

Press SWEEP. The right display should show a voltage rising from approximately uniform

32.

Move the cable from the X AXIS connector

33.

Press

34.

Press

35.

Disconnect the cable and reconnect it to the PEN LIFT connector.

36.

Press SWEEP. The right display should momentarily show a TTL high level (greater than then drop display should then show a TTL high level.

steps.

START

STOP

to

the Y AXIS connector.

FREQ. The right display should show between

FREQ. The right display should show between 9.6 and

a TTL

low

level (less than

0.4V)

and remain there until the sweep is complete. The

it

to

the X AXIS connector on the rear

0

-0.01

and

0.01V.

10.4V.

to

1OV

in

2.4V),

3-15

Operation

3-6.

HP-IB

Description

FUNCTIONAL

Model 8903B

CHECKS

The following ten procedures check the Audio Analyzer’s ability

to

process

or

send all of the applicable

HP-IB messages described in Table 3-3. In addition, the Audio Analyzer’s ability to recognize its

is

HP-IB address significant data line which These procedures do not check whether interpreted and executed by the instrument, however,

checked and all of the bus data, handshake, and control lines except D108 (the most

is

not used by the Audio Analyzer) are set to both their true and false states.

or

not all Audio Analyzer program codes are being properly

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:

0

The Audio Analyzer performs properly when operated via the front-panel keys (that is, in local

mode). This can be verified with the Basic Functional Checks.

0

The bus controller properly executes HP-IB operations.

0

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

If the Audio Analyzer appears should be confirmed before attempting

to

fail any of these HP-IB checks, the validity of the above assumptions

to

service the instrument.

The select code of the controller’s HP-IB interface is assumed to be 7. The address of the Audio 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 Audio Analyzer to the bus controller via the HP-IB interface. Do not connect any equipment to the Audio Analyzer’s INPUT.

Equipment

HP-IB Controller

-or-.

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

-or-.

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

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

HP 9825A/98213A (General and Extended

HP 9000 Model 226

or

any HP 9000 series 200 Computer

HP 85B Option 007

Address Recognition

Description

Set the Remote Enable

(REN)

bus

control line false.

Send the Audio Analyzer’s listen address.

~~ ~

Check that the Audio Analyzer’s REMOTE annunciator is

HPL

IC1

7

wrt

728

off

but its ADDRESSED annunciator

BASIC

LOCAL

OUTPUT

7

728

1/0

ROM)

is

on.

3-16

Model 8903B

Operation

Description

Unaddress the Audio Analyzer

I

different address.

L

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are

by

sending a

I

HPL

wrt

729

I

Remote and Local Messages and the LCL Key

Description

Send the Remote message (by setting Remote Enable,

Analyzer

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on.

-message to the Audio Analyzer.

REN,

true and addressing the Audio

to

listen).

-~~

~

1

HPL

rem728 REMOTE 728

Icl 728

I

BASIC

OUTPUT 729

off.

BASIC

LOCAL

I

Check that the Audio Analyzer’s REMOTE annunciator is

~-

Send the Remote message

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on. Press the LCL key on the Audio Analyzer. Check that the Audio Analyzer’s REMOTE annunciator is now

but that its ADDRESSED annunciator remains on.

~ ~

to

the Audio Analyzer.

off

but its ADDRESSED annunciator is on.

rem 728 REMOTE 728

Sending the Data Message

Description HPL

Address the Audio Analyzer to talk and store its output data in variable there

is

no signal at its INPUT.)

Display the value

of

V.

(The output is

V.

E96

since

red 728,V

dsp

V

BASIC

ENTER 7289

PRINT

V

off,

Check that the Audio Analyzer’s REMOTE annunciator is is

on.

The controller’s display should read

9009600000.00

off

but that

(HPL)

its

or

9009600000

ADDRESSED annunciator

(BASIC).

3-17

Operation

Receiving the Data Message

Model

8903B

Description:

messages. The Data messages sent

both their true and false states. This check assumes the Audio Analyzer is able

its own address Audio Analyzer’s LINE switch to OFF, then to

Send the first part

This check determines whether

also

cause the 7 least significant

and

properly make the remote/local transitions. Before beginning this check, set the

or

not the Audio Analyzer properly receives Data

HP-IB

data lines to be placed in

to

handshake, recognize

ON.

Description

of

the Remote message

HPL

BASIC

rem 7 REMOTE 7

(enabling the Audio Analyzer to remote). Address the Audio Analyzer to listen (completing

728,”M2”

OUTPUT

728;“M2”

wrt

the Remote message), then send a Data message (selecting the

SINAD

measurement).

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on. Check that its SINAD key light

is

on.

Local Lockout and Clear Lockout/Set Local Messages

Description:

Lockout message, disabling all front-panel keys. The check Lockout/Set Local message assumes that the Audio Analyzer the remote/local transitions. Before beginning this check, set the Audio Analyzer’s LINE switch to OFF, then to

This check determines whether

is

properly received and executed by the Audio Analyzer. This check

is

able to handshake, recognize

ON.

or

not the Audio Analyzer properly receives the Local

also

determines whether or not the Clear

its

own

address, and properIy make

also

BASIC

REMOTE

Send the

first

Description HPL

part

of

the Remote message

rem

7

(enabling the Audio Analyzer to remote). Send the Local Lockout message. Address the Audio Analyzer to listen (completing

It0

wrt

7

728

LOCAL

LOCKOUT

OUTPUT

728

the Remote message).

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on. Press the Audio Analyzer’s LCL key. Both its REMOTE and ADDRESSED annunciators should remain on.

Send the Clear Lockout/Set Local message.

Check that the Audio Analyzer’s REMOTE annunciator is

IC1

7

off

but its ADDRESSED annunciator

LOCAL

7

Clear Message

Description:

message. This check assumes that the Audio Analyzer is able to handshake, recognize its own address, make the remotejlocal changes and receive Data messages. Before beginning this check set the Audio Analyzer’s LINE switch to OFF, then to ON.

This check determines whether

or

not the Audio Analyzer properly responds to the Clear

7

is

on.

3-18

Model

8903B

Operation

I

Send the

the

Audio

Address the

first

part

Analyzer

Audio

Description

of

the Remote message (enabling

to

remote).

Analyzer

to

listen

(completing the

HPL

rem

wrt

728,“M2”

BASIC

7

REMOTE

OUTPUT

728;”M2”

Remote message), then send a Data message that

selects the SINAD measurement.

I

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on and that

SINAD

the

Send the Clear message (setting the Analyzer’s measurement

key light

is

also

to

AC

on.

LEVEL).

Audio

clr 728 RESET

728

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on and that

AC

the

Abort

LEVEL key light is on.

Message

7

Description

Send the Remote message

to

the

Audio

Analyzer.

HPL

rem

728

BASIC

REMOTE

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are

cli

Send the

Analyzer

I

Abort

message, unaddressing the

to

listen.

Audio

I

Check that the Audio Analyzer’s ADDRESSED annunciator is

7

off.

Note that the BASIC “ABORTIO”

statement sends both the Abort message and the Local message. Thus

If

Analyzer’s REMOTE annunciator should remain on.

REMOTE annunciator should turn

off.

Send the Local message

BASIC is being used, the Audio Analyzer’s

IC1

7

I

if

HPL is being used, the Audio

ABORT10

ABORTIO

7

(HPL

Local message was already sent

with

the

ABORT10

above.)

Address the

output

data

Audio

in

variable

Analyzer

V.

to

talk

and store

its

red

728,V

ENTER

728;V

728

on,

7

only).

7

statement

,

1

(The

mi.

OSA

Check

on.

IJG90

that the

Audio

Analyzey’s REMOTE annunciator is

off

but

its

ADDRESSED

annunciator

3-19

is

Operation Model

8903B

I

Send the Abort message, unaddressing the Audio Analyzer to talk.

Description

I

Check that both the Audio Analyzer’s REMOTE and

Send the serial poll-enable bus command (SPE) through the interface serial poll mode.

On the Audio Analyzer, key in

to

place the Audio Analyzer in

61.3

SPCL.

The right display should show

wti 0,7; wti

Audio Analyzer is in serial poll mode (indicated by the

Send the Abort message, removing the Audio Analyzer from serial

poll

mode.

HPL

cli 7 ABORT10

ADDRESSED

I

annunciators

6,

24 (Series 80 Controllers)

SENDBUS 728;

(Series 200/300 Controllers)

SEND

1.0.

“1”).

cli 7 ABORT10

BASIC

7

are

off.

1,

24

7;

CMD

1,24

This indicates the

7

I

Check that the Audio Analyzer’s right display shows left serial-poll mode upon receiving the Abort message.

Status Byte Message

Description:

message in both the

to

handshake, recognize its own address, and make the remotellocal changes. Before beginning this

check, set the Audio Analyzer’s LINE switch

Place the Audio analyzer in address it to talk (causing it to send the Status Byte message).

Series

200/300 controllers: Define V with

the program instruction:

lOV=O

20 END.

Display the Value

Check that interface The controller’s display should

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

local

and remote modes. This check assumes that the Audio Analyzer is able

Description

serial

poll mode and

of

V.

Audio

(HP

Analyzer’s

IIPL)

used, the Audio Analyzer’s ADDRESSED annunciator may

REMOTE

read

0.00

annunciator is

(HPL)

to

OFF,

or

0

0.0.

This indicates the Audio Analyzer properly

then

to

ON.

HPL

rdS

(728)-V

rds (728)-V

dsp

V

off.

Depending upon the vintage

(Series

BASIC

80

STATUS 728;V

V

Controllers)

200/300 Controllers)

=

SPOLL

PRINT

be

(728)

V

of

either

the

(BASIC).

HP-IB

on

or

off.

Model

8903B

Description

HPL

Operation

~

BASIC

Send the Remote message.

Place

the

Audio Analyzer

address

it

to talk (causing

message). Display the value

Check

HP-IB

or

off.

Require

Description:

that

interface

The controller’s display should read

Service

of

V.

the

Audio

(HF’

HPL)

Message

This check determines whether or not

Service message (set the SRQ

is

able

to

handshake, recognize

messages. Before

beginning

then after the power-up sequence

Description

part

of

the

Send the first the

Audio

Analyzer

Remote message (enablinc

to

remote).

in

serial poll mode and

it

to

send

the

Analyzer’s

used,

REMOTE

the

bus

its

this

check, set the Audio Analyzer’s

is

Status Byte

I

annunciator

Audio Analyzer’s

0.00

(HPL)

control

line

true). This check assumes that the Audio Analyzer

rem

728

REMOTE

(Series

rds

(728)-+V

dsp

V

is

on.

Depending upon the vintage

ADDRESSED

or

0

(BASIC).

the

Audio Analyzer can issue the Require

annunciator may

STATUS

(Series

V

2001300

=

SPOLL

PRINT

728

80

Controllers)

728;V

Controllers)

V

(728)

be

either

own address, make the remote/local changes, and receive

LINE

complete, press the

DISTN

HPL

rem

7

switch

key.

~~~ ~ ~

to

(Series

OFF,

then

BASIC

80

Controllers)

REMOTE

200/300

REMOTE

Co

728

7

ntro

of

to

the

on

Data

ON,

I

le

rs)

Address the Audio Analyzer to listen (completing

Remote message) then send a Data message

be

(enabling a Require Service message to

upon

Instrument Error).

Make the controller wait 2 seconds the

Audio

Analyzer to send the Require Service

(This

step

is

not

message.

time

is

allowed.)

Read the binary status

necessary

of

interface and store the data step,

7

is

the

interface’s select code).

Display the value the

SRQ

bit,

~~~

Check that the

of

the

numbered

SRQ

from

value

to

the controller’s HP-IB

in

variable

bit

(in

0).

is

1,

this

indicating the Audio Analyzer issued the Require Service message

sent

allow time

if

sufficient

V

(in

step,

this

6

is

the

for

dsp“SRQ =”,bit

wrt

728,’22.4SPw

wait

rds

(7)

2000

+V

(6,V)

OUTPUT

(Series

PRINT

(Series

WAIT

STATUS

200/300

V

=

SPOLL

“SRQ

200/300

728;”22.4SP”

2000

80

Controllers)

7;

V

Co

nt

(728)

80

Controllers)

=”;

BIT

Controllers)

ro

“PRINT/SRQ=”BIT(V,G)

Ilers)

(V.7)

3-2

1

Operation Model 8903B

Trigger Message

Description:

message and whether the CLEAR key serves as

and

Clear Key Triggering

This check determines whether

or

not the Audio Analyzer responds

a

manual trigger in remote. This check assumes that

to

the Trigger

the Audio Analyzer is able to handshake, recognize its own address, make the remoteAocal changes,

and send and receive Data messages. Before beginning this check, set the Audio Analyzer’s LINE

to

OFF,

then

to

ON,

switch

I

Send the first part

the Audio Analyzer to remote).

Address the Audio Analyzer to listen (completing the Remote message), then send a Data message

(placing the Audio Analyzer in Hold mode).

Send the Trigger message.

Address the Audio Analyzer data in variable V.

Display the value

Description

of

the Remote message (enabling

of

V.

then, when the power-up sequence

to

talk and store the

I

wrt 728, “TI”

trg

red 728,

dsp

HPL

rem

728

is

compIete, press the DISTN key.

BASIC

7

V

(Series 80 Controllers)

REMOTE 7

(Series 2001300 Controllers)

REMOTE 728

OUTPUT 728;

TRIGGER 728 ENTER 728;

PRINT

V

Check that both the Audio Analyzer’s REMOTE and ADDRESSED annunciators are on. The controller’s display should read 9009600000.00 (HPL)

or

9009600000

(BASIC).

“T1

V

”

3-7.

Address the Audio Analyzerto talkand store the data in variable

Check that the controller’s

V.

“run”

indicator is still

red 728,

on

indicating that

V

the Audio Analyzer. Press the Audio Analyzer’s CLEAR key. The controller’s

off.

turn

REMOTE OPERATION, HEWLETT-PACKARD INTERFACE

it

BUS

ENTER 728:V

has not received data from

“run”

indicator should

The Audio Analyzer can be operated through the Hewlett-Packard Interface Bus (HP-IB). Bus compatibility, programming, and data formats are described in the following paragraphs.

Except for the

LINE

switch, the

s10

and

x

10

keys, the low terminal ground/FLOAT switches, and the Controller Reset Service Special Function, all Audio Analyzer operations (including servicerelated functions) are fully programmable via HP-IB. In addition, rapid-source tuning and rapidfrequency count capabilities (not available from the front panel) are provided in remote operation.

A

quick test

Audio

Analyzer can respond

For more information about HP-IB, refer

Packard Electronic Systems and Instruments Hewlett-Packard Interface

of

HP-IB

is

described under

to

or

send each

Bus”

(HP part

HP-IB

to

number

Functional Checks.

of

the applicable bus messages described in Table

IEEE

Standard

488,

catalog, and the booklet,

These checks verify that the

ANSI

Standard

MC1.l,

“Tutorial Description

5952-0156).

the

Hewlett-

of

3-3.

the

3-22

Model

8903B

Operation

HP-IB

Compatibility

The Audio Analyzer’s complete bus compatibility ANSI Analyzer’s

Standard

MC1.1)

HP-IB

is

described

capabilities in terms

at

the end of Table

of

the twelve bus messages in the left-hand column.

(as

defined by IEEE Standard

3-3.

Table

3-3

488,

and the identical

also summarizes the Audio

Remote Mode

Remote Capability.

(exceptions are the LCL and CLEAR keys). However, front-panel displays and the signal

outputs remain active and valid. In remote, the Audio Analyzer When addressed messages. When addressed Whether addressed or not, the Audio Analyzer Lockout/Set Local, and Abort messages, and in addition, the Audio Analyzer may issue the Require Service message.

Local-to-Remote Mode Changes.

the Remote message. The Remote message

0

Remote enable

0

Device listen address received once (while REN

When the Audio Analyzer switches on

its

front panel

In remote, most of the Audio Analyzer’s front-panel controls are disabled

may

to

listen, the Audio Analyzer will respond

to

talk,

the Audio Analyzer can issue the Data and Status

will

The Audio Analyzer switches

has

two parts. They are:

bus

will

control line

turn on.

(REN)

to

set true.

remote, both the REMOTE and ADDRESSED annunciators

to

respond

is

true).

be addressed

the Data, Trigger, Clear (SDC), and Local

to

the Clear (DCL), Local Lockout, Clear

to

remote operation upon receipt

to

talk

Byte

at

various

or listen.

messages.

of

Local Mode

Local Capability.

instrument

Clear, Local Lockout, Clear Lockout/Set Local, and the Abort messages. When addressed instrument can issue Data messages and the Status can issue the Require Service message.

Remote-to-Local Mode Changes.

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 [FEN] false.) the Audio Analyzer switches

will

In local, the Audio Analyzer’s front-panel controls are fully operational and the

respond

to

the Remote message. Whether addressed or not,

Byte

message, and whether addressed or not,

The Audio Analyzer always switches

If

it

to

local from remote whenever

its

front panel LCL key

it

will

also respond

to

local from remote whenever

is

not in Local Lockout mode,

is

pressed.

Addressing

The Audio Analyzer interprets the byte on the bus’ eight

if

the bus line (IFC) false. Whenever the Audio Analyzer ADDRESSED annunciator on the front panel will turn on.

The Audio Analyzer

to

Table

address setting, refer to the discussion titled

near the end

is

in the command mode: attention control line (ATN) true and interface clear control

is

being addressed (whether in local or remote), the

talk

and listen addresses are switch selectable as described in Section

2-1

for a comprehensive listing

of

all

valid

HP-IB

of

this section.

data

HP-IB

Address

lines as an address or a bus command

address codes. To determine the present

in the

Detailed Operating Instructions

to

talk,

2.

to

the the

Refer

it

3-23

Operation Model

8903B

HP-IB

Data

Trigger

Clear

Message

Applicable

Yes

llable

3-3.

Message

Reference

Table

(1

of

2)

Response and Functions'

All Audio Analyzer operations except the LINE switch, FLOAT switch, and the bus-programmable. and error outputs except the

s10

and

x10

functions are

All

measurement results, special displays,

"

--

"

display are available to the

bus.

If

in remote and addressed to listen, the Audio Analyzer makes a settled measurement according to previously programmed setup.

It

responds equally to bus command GET

and program code T3, Trigger with Settling (a Data message).

Sets SOURCE to 1 kHz and 0 mV, MEASUREMENT LEVEL with the

80

kHz

LP FILTER on, and sets the trigger

to

AC

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

to Device Clear (DCL) and Selected Device Clear

22.2

state. Responds equally

(SDC)

bus

commands.

Controls

AH

1

SH1 T5, TEO,

L3, LEO

GET

DCL

DT1

DCI

SDC

Remote

Local

Local Lockout

Clear Lockout/ Set Local

Pass Control/ Take Control

Yes

No

Remote mode is enabled when the REN bus control line is

REN

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

the Audio 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 and CLEAR are disabled, and entries in progress are cleared.

The Audio Analyzer returns to local mode (front-panel control). GTL

Responds equally to the GTL bus command and the front-panel LCL key. When entering local mode, no instrument settings or functions are changed but entries in progress are cleared. In local, triggering is free run only.

Disables all front-panel keys including LCL and CLEAR. Only

LLO the controller can return the Audio Analyzer to local (front-panel control).

The Audio Analyzer returns to local (front-panel control) and

REN RLI

local lockout is cleared when the REN bus control line goes false. When entering local mode, no instrument settings or functions are changed, but entries in progress are cleared. In

local, triggering is free run only.

The Audio Analyzer has no control capability.

RL1

co

*

Commands, Control lines, and Interface Functions are defined in your controller's manual describes programming in terms of the twelve

3-24

IEEE

Std.

488.

HP-IB

Knowledge

Messages

of

these might not be necessary

shown

in the left column.

i

Model

8903B

Operation

HP-I8

Message

Require Service

Status Byte

Status Bit

Abort

Applicablc

Yes

No

Yes

nble

The Audio Analyzer sets the invalid program code is received. The Audio Analyzer will also set SRQ true, measurement data is ready or when an instrument error occurs.

The Audio Analyzer responds to a Serial bus command by sending an 8-bit byte when addressed to talk. (issuing the Require Service message) bit Status Byte and the bit representing the condition causing the Require Service message to be issued will both be true. The bits in the Status Byte are latched but can be cleared by:

1)

2)

The Audio Analyzer does not respond to a parallel poll.

The Audio Analyzer stops talking and listening.

3-3.

Message Reference Table

Response

SRQ

bus control line true if an

if

enabled by the operator to do

If

the instrument is holding the

removing the causing condition, and

reading the Status Byte.

SRQ

(2

of

2)

so,

when

Poll

Enable

control line true

7 (RQS

(SPE)

bit) in the

I I

and

Controls

Interface

Functions‘

T

SPE

SPD

I

IF‘

T5,

I

PPO

T5,

I

L3,

TEO

TEO,

LEO

’

Commands, Control lines, and Interface Functions are defined in your controller’s manual describes programming in terms of the twelve

Complete HP-IB capability as

SR1, RL1,

LEO,

Local

Analyzer

in

(and

Lockout.

to

an unknown state. To prevent

the

CLEAR key)

PPO,

When

local mode

DC1,

by

and

defined

DT1,

a data transmission is

pressing

allows return-to-local only

CO,

the

this,

in

IEEE

Std.

El.

LCL

key,

the

a

local lockout is recommended. Local lockout disables

IEEE

488

interrupted,

data

under

NOTE

Return-to-local can also be accomplished

LINE

switch to

OFF,

then back to

ON.

disadvantages:

0

It defeats the purpose and advantages of local lockout (that is, the system controller will lose control

0

There are several

HP-IB

conditions that reset to default states at

turn-on.

Std.

488.

HP-IB

and

ANSI

could

program control.

by

Knowledge

Messages shown in the left column.

Std.

which can happen

be

lost. This would leave

turning the Audio Analyzer’s

of

these might not be necessary if

MC1.l is:

SH1,

by

returning

AH1,

the

However, this technique has several

of

a system element).

T5,

TEO, L3,

the

Audio

Audio Analyzer

the

LCL

key

-

3-25

Operation

Data Messages

The Audio Analyzer communicates on the interface bus primarily with data messages. Data messages

or

consist of one

more bytes sent over the 8 control line [ATN] false). Unless addressed to listen. Unless Status Byte message in local mode may be performed in remote mode via the LINE switch, FLOAT switches, the Function. In addition, the Audio Analyzer may be triggered via data messages at a particular time.

Receiving the Data Message

Depending on how the internal address switches are set, the Audio Analyzer can either talk only, talk status only, listen only,

it

messages when Listen Only. If not set Abort message

is

or

until its talk address

Model 8903B

data

bus lines, when the bus is in the data mode (attention

it

is

set

to

Talk Only, the Audio Analyzer receives

it

is

set to Listen Only, the Audio Analyzer sends data messages

(if

enabled) when addressed to

+lo

or

talk and listen both (normal operation). The instrument responds to Data

enabled

to

remote (REN control line true) and

to

Listen Only, the instrument remains addressed to listen until

or

a universal unlisten command is sent by the controller.

or

talk.

Virtually all instrument operations available

data

messages. The only exceptions are changing

x10

keys, and the Controller Reset Service Special

it

is addressed to listen

data

messages when

to

make measurements

it

or

set to

receives

the

an

Listen

in the Listen Only mode when the remote enable bus control line (REN) then responds to all Data messages, and the Trigger, Clear, and Local Lockout messages. However,

is

Only.

If

the internal LON (Listen Only) switch is set to

inhibited from responding to the Local

“l”,

the Audio Analyzer is placed

is

set true. The instrument

or

Abort messages and from responding to a serial poll with

it

the Status Byte message. Listen Only mode is provided

to

allow the Audio Analyzer to accept programming from devices other

than controllers (for example, card readers).

Data input Format.

With the exception of the Rapid Source mode, each code keystroke in local mode. Thus, for a given operation, the program string the same as the keystroke sequence in local mode.

Rapid Source

in the

The Data message string,

or

program string, consists of a series of ASCII codes.

(For

Detailed Operating Instructions.)

is

typically equivalent

syntax

to

a front-panel

in remote mode

is

information about RS, Rapid Source, refer to

Example 1 shows the general-case programming

order for selecting Audio Analyzer functions. Specific program order considerations are discussed in

the following paragraphs under

“Program Order Considerations.

together as a continuous string as typified in Example

hnctions (with Automatic Operation),

programs

the source

2.

The string in Example 2 clears most Special

”

AI1 functions can be programmed

to

440

Hz

at

lV,

selects a distortion

measurement with 30 kHz low-pass filtering and log units, then triggers a settled measurement.

Program

summarized in Table

Codes.

Most all of the valid HP-IB codes for controlling Audio Analyzer functions are

3-6.

All front-panel keys except the LCL key and the

+lO

and

x10

keys have

corresponding program codes (exception: Service Special Functions).

Table

3-4

shows the Audio Analyzer’s response to various ASCII characters not used in

its

code set.

The characters in the top column will be ignored unless they appear between two characters of a

if

program code. The characters in the bottom column,

24

cause Error

(invalid HP-IB code) to be displayed and a Require Service message to be generated.

received by the Audio Analyzer, will always

The controller 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.

3-26

Model

8903B

Operation

lbble

EXAMPLE

Audio Analyzer Listen

[Automatic Operation] [Source Frequency] [Source Amplitude] [Measurement] [Filters] [Special Functions] [LoglLin] [Ratio] [Start Frequency].

.

.[Stop Frequency] [Plot Limit] [Sweep] [Trigger]

1:

General Program

Controller Talk

*Excluding Rapid Source

Syntax

1

or

Rapid Frequency CountModes.

3-4.

I

(9

B

G

tExcept

gram code.

and

Audio Analyzer Response

lgnoredt

Generate Error

E

when inserted

Protocol'

I

J

Q

Y

Z

\

between

[

1

24

two

characters

to

Unused ASCII Codes

n

I

of

N

DEL

a

pro-

1

I

.

EXAMPLE

Audio Analyzer Listen

2

Typical Program String

Controller Talk

Automatic Operation2

Source Frequency Log

Source Amplitude

Turning

filters), and Low-Pass Filters, and Ratio functions toggle remote mode, these functions do not toggle on and code which turns given in the following table.

off

Functions.

AU

FR440HZAPl

-TTTTTT_

When operating in local mode, the High-Pass/Bandpass (optional plug-in

off

all the keys in the group. The

HP/BP

LP

FILTERS

Function

FILTERS

RATIO

SWEEP

off

I

VLM3L1

all

off

LGT3

Trigger With Settling

30

kHz

Low-Pass

Distortion

on

and

off

with successive keystrokes. In

off.

Instead, each of the above groups has a specific

HP-IB

off

codes for turning

I

HP-IB

Code

HO

LO

RO

off

I

Filter

these functions are

wo

Programming Numeric Data.

references, plot limits,

or

When programming source amplitude

issuing any numeric data (other than specific

Analyzer, certain precautions should be observed. Numeric

or

frequency, entering ratio

HP-IB

data

may be entered in fixed, floating

codes) to the Audio

3-27

Operation

Model

8903B

point,

may fall between any two digits of the mantissa but should not appear ahead of the

or

exponential formats. Usually, numeric

data

(including leading zeros), one decimal point, and one-

consists of a signed mantissa of up

or

two-digit signed exponent. The decimal point

to

first

five digits

digit.

If

it

does, a leading zero will be automatically inserted by the Audio Analyzer. Any digit beyond the five

data

entry

is

allowed for the mantissa will be received as zero. The general format for numeric below, followed by several examples illustrating various entries and the resulting

data

as

given

received by

the Audio Analyzer.

General Numeric Data Input Format:

f

DJ

D

D]l

Nf

5-Digit Signed Exponent Magnitude

Mantissa

Indicates Exponent

Follows

Exponent Sign

Example: + .123453+01 issued

0.123403+01 received by Audio Analyzer

Example: +1234563+01 issued

1234503+01 received by

Audio Analyzer

Example: +00012345 issued

12000 received by

Audio Analyzer

In general, do not issue numeric

data

with more significant digits than can be displayed on the Audio

Analyzer’s left five-digit display.

NOTE

The above numeric data input format information does not apply to the

Rapid Source mode. Refer to Rapid Source

in

the

Detailed Operating

Instructions.

Triggering Measurements with the Data Message.

programming local operation, the Audio Analyzer measurement is completed. In remote (except

is

the selection of free run, standby,

is

allowed to free run outputting data

or

in

sweep), three additional operating modes are allowed

Hold, Trigger Immediate, and Trigger with Settling. In addition, the CLEAR key can act

A feature that

triggered operation

is

only available via remote

of

the Audio Analyzer. During

to

the display as each

as

a manual trigger while the instrument is in remote. The trigger modes and use of the Clear key are described below.

Free Run

when no other trigger mode has been selected. The measurement result

(TO).

This mode is identical to local operation and is the mode of operation in effect

data

available

to

the bus are

constantly being updated as rapidly as the Audio Analyzer can make measurements. A Device Clear

or

message

entry into remote from local sets the Audio Analyzer

NOTE

to

the Free Run mode.

3-28

nee Run triggering (code

the sweep function (code

or

use of CLEAR key triggering will cause only the start frequency point to

TO)

is the only trigger mode allowed when using

Wl).

Any other triggering (codes

TI,

T2,

or

T3)

be displayed, plotted, and read to the HP-IB. Both the rear-panel X AXIS and

Y

AXIS outputs will be inhibited from continuing beyond the start

frequency point.

Model 8903B

Hold

T3, the Trigger message, instrument itself However, the instrument

to

issue the Require Service message if an HP-IB code error occurs. The instrument will issue the Status Byte message if serial polled. and return the instrument to Hold.)

(Tl).

This mode

the rear-panel X AXIS

is

or

by the user via the bus. Thus, the signal at the MONITOR output

Operation

used to set up triggered measurements (initiated by program codes T2

or

the CLEAR key). In Hold mode, internal settings can be altered by the

can

is

inhibited from outputting any

or

Y

AXIS outputs,

(A

serial poll, however, will trigger a new measurement, update displays

or

to

data

to the front-panel key lights and display,

the HP-IB except as follows. The instrument will

or

change.

Upon leaving Hold, the front-panel indications are updated The Status Byte will be affected (and the Require Service message issued) by the events that occur during the new measurement cycle. The Audio Analyzer leaves Hold when Run, Trigger Immediate, Trigger with Settling codes,

pressed

Trigger Immediate

measurement in the shortest possible time. The instrument then waits for the measurement results read. While waiting, the instrument can process most bus commands without losing the measurement results. However,

listen address, the Measurement results obtained via Trigger Immediate are normally valid only when the instrument is in a steady, settled state.

Trigger with Settling

Analyzer inserts a settling-time delay before taking the requested measurement. This settling time is sufficient to produce valid, accurate measurement results. Trigger with Settling executed when a Trigger message is received via the bus.

Triggering Measurements with the

and not in Local Lockout, the front-panel CLEAR key may be used instruction. Place the instrument in Hold mode (code Audio Analyzer performs one Trigger with Settling measurement cycle, then waits for the

read. Once the between trigger cycles,

(if

not in Local Lockout),

(T2).

When the Audio Analyzer receives the Trigger Immediate code,

if

the instrument receives GTL

or

if

it

is

triggered by the CLEAR key, a new measurement cycle

data

(measurement results) are read onto the bus, the Audio Analyzer reverts to the Hold mode.

(T3).

data

is read out to the bus, the instrument returns

it

will be replaced with

or

when it returns

Trigger with Settling is identical to Trigger Immediate except the Audio

CLEAR

Key.

or

to

(Go

To Local), GET (Group Execute Trigger), its

When the Audio Analyzer

Tl).

data

acquired from subsequent measurements.

as

the new measurement cycle begins.

it

receives either the Free the Trigger Message, when the CLEAR key is local operation.

it

makes one

to

be

will

be executed. Once

is

the trigger type

is

in remote Hold mode

to

issue a Trigger with Settling

Each time the CLEAR key is pressed, the

data

to be

to

Hold mode.

If

data is not read

When

in

Special Considerations for Triggered Operation.

pay attention to all universal bus commands, for example, “serial poll enable (SPE)”

,

(LLO)”

commands, such as, “go the Audio Analyzer must interrupt the current measurement cycle to determine whether any action in response measurement must be reinitiated following each interruption. Thus, the Audio 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 Immediate measurement to be interrupted; indeed, even

the

as discussed under Trigger Immediate above, with no loss of where many bus commands are present, Trigger Immediate failsafe operation.

etc. In addition,

to

these commands

(T2)

and Trigger with Settling (T3) codes are received, the Audio Analyzer will not allow its

measurement

is

if

it

is addressed to listen,

to

local (GTL)”, “group execute trigger (GET)”, etc. As a consequence

is

necessary. Since many elements of the measurements are transitory, the

handshake

complete. Once the measurement is complete, bus commands will be processed,

free-run mode, the Audio Analyzer must

,

“local lockout

it

must pay attention

if

much bus activity occurs while

of

bus

commands

data.

Thus, in an HP-IB environment

or

Trigger with Settling should be used for

to

all addressed bus

are

inhibited

of

until

3-29

this,

Operation

e

Model 8903B

NOTE

Bee Run triggering (code

the sweep function (code

or

use of

CLEAR

be displayed, plotted, and read to the HP-IB. Both the rear-panel X AXIS

and

Y

AXIS outputs will be inhibited from continuing beyond the start

frequency point.

Reading Data from the Right or Left Display.

once for each measurement made. Only the information on one display can be read each time. Use the codes RR (read right display) display will remain selected until the opposing display

or

power-up occurs). measurement results (always occupying the right display onIy) are placed on the bus (when requested) regardless of which display is enabled.

Program Order Considerations.

order, some program order considerations need highlighting.

Automatic Operation (AU).

it

remote

many other Special Functions. Thus when AUTOMATIC OPERATION is used, it should appear at the beginning of a program string.

sets all Special Functions prefixed 1 through 8 to their zero-suffix mode, and also affects

Errors

key

(which occupy

As

TO)

is the only trigger mode allowed when using

Wl).

Any other triggering (codes

triggering will cause only the start frequency point to

The Audio Analyzer can only read data

or

RL (read left display) to control which information is read. The

is

specified

two

displays) are output as described above, and DC LEVEL

Although program string

in local mode, when AUTOMATIC OPERATION

(or

syntax

T1,

T2,

or

T3)

until a clear message

is virtually identical

to

the HP-IB

is

received

to

keystroke

is

executed in

Frequency or Amplitude Increment Step Up or Step Down (UP or DN).

Down (DN) increment. The parameter changed is dependent upon which increment command was executed last. To insure the correct modification, program either Frequency Increment

(AN) immediately before the UP

Trigger Immediate and Trigger with Settling

T3

is

received by the Audio Analyzer, a measurement is complete, some bus commands can be processed without losing the measurement results. However, any HP-IB program code sent to the Audio Analyzer before the triggered measurement results have been output will initiate a new measurement. a program string, and the triggered measurement results must be read before any additional program codes are sent.

Sending

the

Depending on how the internal address switches are set, the Audio Analyzer can either talk only, talk status only, listen only, instrument sends Data messages when addressed to talk. The instrument then remains configured to talk untiI must send either an Abort message,

Talk

Only Mode.

Only) switch is set to

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

If

data.

cycle

is

executed, the frequency

Data

it

the listener is not ready and the Audio Analyzer is not in a trigger mode, another measurement

executed.

Message

or

talk and listen both (normal operation).

is unaddressed to talk by the controller.

If

the internal address switches are set to a valid Talk address and the TON (Talk

“l”,

the Audio Analyzer is placed in the Talk Only mode. In this mode instrument

or

the amplitude

or

DN command.

a

new talk address,

is

modified

(12

and T3).

is

Thus,

trigger codes should always appear at the end of

To

When either of the trigger codes

immediately initiated. Once the measurement

unaddress the Audio Analyzer, the controller

or

a universal untalk command.

When a Step Up (UP)

as

determined by the established

(FN)

or

Amplitude Increment

If

set to both talk and listen, the

is

not ready for

or

Step

T2

or

3-30

Model 8903B

Operation

Talk Status

to

“l”, but the Only mode. In this mode the instrument bus is in the successfully sent on the bus, the internal Status

is

pulsed each time the one-byte Data message is sent.

Data Output Format.

exponential

E

and a signed power-of-ten multiplier. (Refer

Instructions

(CR) and a line feed example, Hz, volts, fifth digit

Data Output Format:

Only

Mode.

LON

data

mode. The byte sent

If

all the internal address switches and the

(Listen Only) switch

is

set

to

is

configured to send a one-byte

is

an exact copy

Byte

As

shown below, the output

form:

first the sign, then five digits (leading zeros not suppressed) followed by the letter

to

for the only exceptions to this format.) The string

(LF),

string positions

dB,

%,

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

of

the mantissa. Data values never exceed 4 000

Signed Mantr

Indicates Exponent

Exponent Sign Exponent Magnitude

11

and

kDDDDDEkNNCRLF

Follows

NOTE

TON

(Talk Only) switch are set

“0”,

the Audio Analyzer is placed in the Talk Status

data

message whenever the

of

the Status Byte. Each time this byte

is

cleared. The Data Valid (DAV) handshake line

data

is

usually formatted

Rapid

J[TJ-J--

12.

frequency

Data

is

000

Carriage Return

Count

is

terminated by a carriage return

always output in fundamental units (for

is

assumed

000.

Line

Feed

in

as

a real constant in

the

Detailed Operation

to

be

to

the right of the

is

For

the only exception to the above format, refer to

in the

Detailed Operating Instructions.

When an error of the numeric digits have predetermined values as shown below. Error outputs always exceed

000

000.

error code can be derived from the string by subtracting 9

Error

Output Format:

is

output

The two-digit error code

to

the bus,

Error Code Carriage Return

it

follows the same twelve-byte format described above except most

is

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

+900DDE+05CRLF

Rapid F’requency Count

x

lo9, then dividing the results by 100

Line Feed

Receiving the Clear Message

The Audio Analyzer responds to the Clear message by assuming the settings detailed in Table 3-5. The Audio Analyzer responds equally to the Selected Device Clear (SDC) bus command when addressed 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 such that the Require Service message will be issued on HP-IB code errors only

(22.2

SPCL).

Receiving the Trigger Message

When in remote and addressed to listen, the Audio Analyzer responds one settled-measurement cycle. The Audio Analyzer responds equally to Execute Trigger bus command [GET]) and a Data message, program code T3 (Trigger with Settling).

to

a Trigger message by executing

a

Trigger message (the Group

9

000

000.

to

22)

Refer

to

Message.

the paragraph

“Diggering Measurements with the Data Message”

under

Receiving the Data

3-31

Operation

Receiving the Remote Message

Model

8903B

The Remote message has then the device listen address Analyzer in remote mode. Thus, the Audio Analyzer is enabled

two

parts. First, the remote enable bus control line (REN) is held true,

is

sent by the controller. These

two

actions combine to place the Audio

to

go into remote when the controller

begins the Remote message, but it does not actually switch to remote until addressed

to

first time. No instrument settings are changed by the transition from local

to

mode is set

Free Run (code

REMOTE annunciator. When the Audio Analyzer

TO).

When actually in remote, the Audio Analyzer lights its front-panel

is

being addressed (whether in remote

remote, but the Trigger

front-panel ADDRESSED annunciator turns on.

I

Start Frequency Stop Frequency

nble

Parameter

3-5.

Response

20

Hz

20

kHz

to

a Clear Message

Setting

Plot Limits

Lower Upper

X-Y

Recorder Frequency Frequency Increment

Amplitude Amplitude Increment

Measurement Detection Low-Pass (LP) Filter

High-Pass

Bandpass

SPCL

(HP)/

(BP)

Filter

-1

00.0

+100.0

Enabled

1000.0

0.00

0.1

AC

RMS

80

All

Hz

mV

oov

Level

kHz Low-Pass

off Special Functions off or

On

set

to their

zero-suffix mode except Service Request

to

22.2

Ratio Log/Lin

Condition set

Off

Linear (refer to

(HP-IB

RATIO

and

LOG/LIN

code error).

Detailed Operating Instructions.)

Right

Display Read

Service Request Condition

Status Byte

Trigger Mode

Local Lockout

Enabled

HP-IB

Cleared

Run

Free

Cleared

Code Error

(Code

Only

TO)

to

listen the

or

local), its

Receiving the Local Message

The Local message is the means by which the controller sends the

to

listen, the Audio Analyzer returns to front-panel control when it receives the Local

If

the instrument was in local lockout when the Local message was received, front-panel

returned, but lockout is not cleared. Unless it receives the Clear Lockout/Set Local message,

3-32

If addressed message. control

is

the Audio Analyzer will return to local lockout the next time it goes to remote. are changed by the transition from remote to local, but all measurements are made in a free run mode.

Go

To

Local (GTL) bus command.

No

instrument settings

Model 8903B Operation

When the Audio Analyzer goes However, when the Audio Analyzer

to

local mode, the front-panel REMOTE annunciator turns

is

being addressed (whether in remote

or

local),

its

ADDRESSED annunciator lights.

If

the Audio 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 Audio Analyzer's front-panel keys entirely using the Local Lockout message.

Receiving the Local Lockout Message

The Local Lockout message is the means by which the controller sends the Local Lockout (LLO) bus

If

command.

in remote, the Audio Analyzer responds to the Local Lockout Message by disabling the

front-panel LCL (local) and CLEAR keys. (In remote, CLEAR initiates a Trigger with Settling cycle.)

of

data

or

The local lockout mode prevents loss

system control due to someone accidentally pressing

front-panel keys. If, while in local, the Audio Analyzer is enabled to remote (that is, REN

it

and it receives the Local Lockout Message,

it

is

time

addressed

by the controller (using the Local

OFF

to

and back to ON,

to

listen. When in local lockout, the Audio Analyzer can be returned

or

Clear Lockout/Set Local messages), by setting the LINE switch

or

by removing the bus cable.

will switch to remote mode with local lockout the first

to

Receiving the Clear Lockout/Set Local Message

The Clear LockoutjSet Local message is the means by which the controller sets the Remote Enable

(REN) bus control line false. The Audio 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

to

from remote with local lockout REMOTE annunciator turns

local. When the Audio Analyzer goes

off.

to

local mode, the front-panel

off.

front-panel

is

set true)

local only

Receiving the Pass Control Message

The Audio Analyzer does not respond to the Pass Control message because

it

cannot act

as

Sending the Require Service Message

The Audio Analyzer sends the Require Service message by setting the Service Request (SRQ) bus

in

control line true. The instrument can send the Require Service message mode. The Require Service message is cleared when

Clear message

is

received by the Audio Analyzer. (During serial poll, the Require Service message

serial poll

is

executed by the controller

a

cleared immediately before the Audio Analyzer places the Status Byte message

a

code error will always cause conditions which can be enabled to cause the Require Service message

Require Service message to be issued. In addition, there are

to

three conditions are described below:

0

Data Ready: When the Audio Analyzer

is

ready to send any information except error codes

the Status Byte.

0

HP-IB Code Error: When the Audio 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 Service message

to

be

sent.

by

Error

31

which causes the Require

either local or remote

on

the bus.) An HP-IB

be sent when they occur. All

a controller.

or

if

is

two

other

or

a

0

Instrument Error: When any Error is being displayed by the Audio Analyzer, including the HP-IB Code error (Error

24).

3-33

Operation

Selecti.ng the Service Request Condition

Model 8903B

Use Special Function

Service message Require Service message to be sent). The Service Request Condition Special Function either the front panel disabled by the Clear message. procedure for enabling the various conditions are given under

Operation Instructions.

simply by triggering measurements then reading the output data. In certain applications, the controller must perform other tasks while controlling the Audio Analyzer. Figure 3-7 illustrates a flow chart for developing device subroutines using the instrument’s ability data is ready. This subroutine structure frees the controller

is

Analyzer

ready with data.

on

22,

Service Request Condition,

any

of

the above conditions (except

or

via the HP-IB. The conditions enabled by Special Function

A

description of the Service Request Condition Special Function and the

Normally, device subroutines for the Audio Analyzer can be implemented

to

enable the Audio Analyzer to issue the Require

HP-IB

code errors which always cause the

is

entered from

22

Service Request Condition

to

issue the Require Service message when

to

process other routines until the Audio

in the

Sending the Status Byte Message

The Status Byte message consists of one 8-bit byte in which 3 of the bits are set according to the

enabled conditions described above under three conditions previously described are both enabled and present, all the bits corresponding to the

also

conditions (and

of

one 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

paragraph 3-7,

Once the Audio Analyzer receives the serial poll enable bus command alter the Status Byte. When addressed to talk (following SPE), the Audio Analyzer sends the Status Byte message.

the above conditions occurs but has not been enabled by Special bction

bit 7 the

HP-IB Syntax and Characteristics Summary

RQS

Sending the Require Service Message.

bit) will be set true, and the Require Service message is sent. If

is

shown in the table labeled “STATUS Byte:,” under

on the following pages.

(SPE),

If one

or

more of the

22,

neither the bit

it

is

no longer allowed to

are always

Detailed

NOTE

Since the Audio Analyzer cannot alter the Status Byte while

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 command is received, if the Abort message is received,

or

Regardless of whether

Service message pending will be cleared if a Clear message is received. If the instrument

Only, the Status Byte is cleared each time the one-byte Data message is issued to the bus.

not the Status Byte message has been sent, the Status

or

if the Audio Analyzer is unaddressed to talk.

if

the Serial Poll Disable (SPD) bus

in

serial poll

Byte

and any Require

is

Sending the Status Bit Message

The Audio Analyzer does not respond to a Parallel Poll Enable (PPE) bus command and thus cannot send the Status Bit Message.

Receiving the

The Abort Message is the means by which the controller sets the Interface Clear (IFC) bus control line true. When the Abort message is received, the Audio Analyzer becomes unaddressed and stops talking

or

listening.

Abort

Message

set to Talk

3-34

Model

8903B

Operation

START 89038

<

SET TRIGGER

MODE TO HOLD

(HP-I8 CODE T1)

ENABLE

DATA READY

(HP-16 CODE 22.3SP)

MEASUREMENT

TRIGGER MEASUREMENT

(HP-16 CODE T2

I

SRQ

1

CONF 1 GURE

OR

T3).

ON

QNTERRUP;

ON

SRO)

1

READ STATUS BYTE

I

FROM 89038

-1

1

A

TO OTHER INSTRUMENT

SERVICE ROUTINES

SERVICE ROUTINES 89038

~

TEST OTHER 89038 No

SRO

CONDITIONS DUE TO DATA

I

No

I

SA0

FROM

READ DATA

FROM 89038

I

Figure

3-7.

PROCESS OTHER ROUTINES UNTIL

SRQ

CAUSES INTERRUPT

3-4.

Example

HP-IB

SYNTAX AND CHARACTERISTICS SUMMARY

Address:

21,

HP-IB

General Operating Syntax:

Operation] [Source Frequency] [Source Amplitude] [Measurement] [Filters] [Special Functions] [Log/Lin] [Ratio]

...[

Start Frequency] [Stop Frequency] [Plot Limit] [Sweep] [Trigger]

Numeric Data Input Format:

Flow

Set in binary by internal switches - may be displayed on front panel using Special Function Address. (Factory set

5-Digit Signed Mantissa

(leading decimal not allowed)

I

Chart for Driving the Audio Analyzer Using the Require Service Message (SRQ

to

28

decimal;

(Excluding Rapid Frequency Count and Rapid Source modes.)* [Automatic

(Except in Rapid Source mode.)*

+DDDDDE+NN

11100

binary.)

Exponent Magnitude

Exponent

Indicates Exponent Follows

A

RETURN

Sign

...

*For

information on

Rapid

Frequency Count

or

Rapid Source modes refer

to

them by name

in

the Detailed Operating Instructions.

3-35

Operation Model

8903B

Output Formats:

(Except in Rapid Frequency Count mode.)* Data (valid

and in fundamental units):

+DDDDDE+NNCRLF

Indicates Exponent

Errors

:

Return to Local:

Front panel LCL key

Manual Trigger:

Signed MantissarT[l

Follows

Exponent Sign Exponent Magnitude

+900DDE+05CR

Error Code Line Feed

if

not locked out.

T

fiont panel CLEAR key initiates Trigger with Settling measurement.

Status Byte:

T

Carriage Return

LF

Carriage Return

data

output value always

Line Feed

<9

x

IO9

Bit

Weight Service

Request

Condition

Complete HP-IB Capability

L3, LEO, SR1, RL1,

8

128

0

(always) Service

PPO,

7

64

RQS

Bit

Require

(as described in

DC1,

DT1,

6 5 4

32

0

(always) 0 (always) 0 (always) ment Code Ready

16

8

3 2 1

4

Instru-

2

HP-IB

Data

Error Error

IEEE

Std

488,

and ANSI Std MC1.l): SH1, AH1, T5, TEO,

CO,

El.

1

*For information on Rapid Frequency Count or Rapid Source modes refer

3-36

to

them

by

name in the Detailed Operating Instructions.

Model

8903B

Zbble

3-6.

Audio Analyzer Parameter to HP-IB Code Summary

Operation

Source

Function

Start Frequency Stop Frequency Plot Limit

Frequency Increment Amplitude Amplitude Increment

Data

-

(minus)

Clear*

0-9

.(decimal point)

Units

kHz

V

Upper Limit

Hz mV Lower Limit dB dBm into

Parameter

600R

(dBre.775V)

Program

FA FB PL FN

AP

AN

-

CL

0-9

KZ VL

UL HZ MV

LL

DB

DV

Code

Parameter

Internal Plug-in HP/BP Filters

Left Plug-in Filter on Right Plug-in Filter on

All Plug-in HP/BP Filters

LP Filters

30

kHz

LP Filter on

80

Khz LP Filter on

All LP Filters

Ratio

On

Off

Log/Lin

Log Lin

Trigger Modes

Free Run

Hold Trigger Immediate Trigger with Settling

off

Program

H1

H2

HO

L1

L2

LO

R1

RO

LG LN

TO T1 T2 T3

Cod4

Sweep on Sweep

t

(step UP)

1

(step down)

Automatic Operation

SPCL SPCL SPCL

Measurements

off

AC Level SINAD Distortion DC Level Signal-to-Noise

Distortion Level RMS Detector AVG Detector Automatic Notch Tuning

Notch Hold

Not to

be confused

with

Clear message which

w1

wo

UP

DN

AU

SP

ss

M1 M2 M3

s1

52

s3

A0

A1

NO

N1

is

defined

Miscellaneous

in

Table

3-3.

Read Left Display Read Right Display Rapid Frequency Count Rapid Source

RL

RR

RF

RS

3-37

Operation

Model

8903B

kogram Code

A0 A1 AN AP AU

'CL

DV DB DN

FA FB FN FR

HZ

HO H1 H2

KZ

LG LN

LL LO L1 L2

MV

M1 M2

M3

%ble

All Internal Plug-in HP/BP Filters

3-7.

Audio

Parameter

RMS Detector

AVG Detector

Amplitude Increment

Amplitude

Automatic Operation

Clear

dBm into

6000

(dBre.775V)

dB

1

(stepdown)

Start Frequency

Stop Frequency

Frequency Increment

Frequency

Hz

Left Plug-in Filter on

Right Plug-in Filter on

kHz

Log

Linear

Lower Limit

All

LP Filters

30

kHz LP Filter on

80 kHz LP Filter on

mV

AC Level

SlNAD

Distortion

Analyzer

off

HP-IB

off

Code

to

Parameter Summary

Program Code

NO

N1

PL

RF RL

RR

RS

R1 RO

SP

ss

s1

s2

s3

TO

T1

T2

T3

UP

UL

VL

wo

w1

-

0-9

Parameter

Automatic Notch Tuning

Notch Hold

Rapid Frequency Count

Read Left Display

Read Right Display

Rapid Source

Ratio On

Off

Ratio

SPCL

SPCL SPCL

DCLevel

Signal-to-Noise

Distortion Level

Free Run

Hold

Trigger immediate

Trigger with Setting

t

(stepup)

Upper Limit

V

Sweep

off

Sweep on

-(minus) 0-9

.(decimal point)

3-38

rev.

15FEB89

Model

8903B

3-8.

Audio Analyzer Special finction to

HP-IB

Code

Summary

(1

Operation

of

2)

Special Function

Input Level Range (except DC Level)

Automatic Selection 300V range 189V range 119V range

7.54V range

47.6V range

30.0V range

18.9V range

11.9V range

7.54U range

4.76V range

3.00V range

1.89V range

1.19V range

0.754V range

0.476V range

0.300V range

0.1 89V range

0.1 19W range

0.0754V range

Program

1

.OSP

1.1

1.2SP

1.3SP

1.4SP

1.5SP

1.6SP

1.7SP

1.8SP

1.9SP

1.1OSP

1.11SP

1.1

2SP

1.13SP

1.14SP

1.15SP

1.1

6SP

1.17SP

1.1

8SP

1.19SP

Code

SP

Special Function

Notch Tune

Automatic notch tuning Hold notch tuning

SINAD Meter Range

0

to M 18

0

to

dB

x

24 dB range

range

Error Disable

All

errors enabled

Disabled Analyzers errors

(Errors 12-17, 31, and 96)

Disable source errors

(Errors 18 and 19)

Disable both Analyzer and

Source errors

Hold Settings

Hold input level ranges, post-notch gain, decimal point and notch tuning at present settings

*ogram

6.05p

61 SP

7.05p

7.1 SP

8.05p

8.1 SP

8.25p

8.35p

9.05p

Code

Input Level Range (DC Level only)

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

mV

DD.DD D.DDD O.DDDD

range

mV

range

mV range

2.OSP

2.1SP

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

Display Source Settings

Display source settings as

in

entered. Frequency

left

display; amplitude in right display.

Re-enter Ratio Mode

Restore last RATIO reference

if

and enter RATIO mode

allowed.

Display RATIO reference

Signal-to-Noise Measurements Delay

Automatic Selection 200 ms delay 400 ms delay 600 ms delay 800 ms delay

1

.Os

delay

1.2s

delay

1.4s delay

1.6s delay

1.8s

delay

X-Y

Recorder

Enable plot Disable plot

1O.OSP

11

.OSP

11.1SP

12.0SP

12.1SP

12.2SP

12.3SP

12.4SP

12.5SP

12.6SP

12.7SP

12.8SP

12.9SP

13.0SP

13.1 SP

3-39

Operation

Model

8903B

mble

3-8.

Audio Analyzer Special hnction to

Special Function

~~

Post Notch Detector Response (except in SINAD)

Fast RMS Detector Slow RMS Detector Fast AVG Detector Slow AVG Detector

Quasi-peak Detector

SINAD and Signal-to-Noise Display Resolution

0.01 dB above 25 dB;

0.5

dB below 25 dB

0.01 dB all ranges

Sweep Resolution

(maximum 255 pointstsweep) 10 pointstdecade

1

point/decade

2 pointstdecade

5

pointstdecade 10 pomts/decade 20 pointsldecade

50

points/decade

100

pointstdecade

200 pointstdecade

500 pointsldecade

Display Level in Watts

Display level as watts into 8R Display level as watts into NNNR

Program Code

5.0SP

5.1SP

5.2SP

5.3SP

5.7SP

16.0SP

16.1 SP

17.0SP

17.1SP

17.2SP

17.3SP

17.4SP

17.5SP

17.6SP

17.7SP

17.8SP

17.9SP

19.OSP

19.NNNSP

HP-IB

Code

Summary

Special Function

Time Between Measurements

Minimum time between

measurements

IS

Add

Read Display to HP-IB

Read right display Read left display

HP-IB Address

Displays HP-IB address (in binary)in left display; right display in form TLS where T=l means talk only; means listen only; S =1 means SRQ

Displays HP-18 address in

decimal

HP-IB Service Request Condition

Enable a Condition to to cause a

service request, N is the sum of any combination weighted conditions below:

4-Instrument error The instrument powers up in the 22.2 state (HP-IB error).

Source Output Impedance

(Instrument powers up at 6000)

between measurements

l-Data Ready 2-HP-IB error

6000

of

L=l

of

the

50fl

(2

of

2)

'rogram Code

14.0SP

14.1SP

20.0SP

21 .OSP

21.1 SP

22.NSP

47.0SP

47.1 SP

3-40

Model

8903B

Operation

ASCII

NUL SOH

STX ETX

EOT ENQ

ACK

BEL

BS

HT LF

VT

FF

CR

so

SI

OLE DC1 DC2 DC3

DC4 NAK SYN

ETB CAN

EM

SUB

ESC

FS

GS

RS

us

SP

'

"

#

$

010

8

'

(

)

+

,

-

I

0

1 2 3

4 5 6 7

8 9

;

<

'

7

Binary

00OOOOOO

00OOO001

00OOO010

00OOO011

00MN)lOO 00OOO101 00O00110

00OOO111 00001

OOO

00001001 00001 010

00

001 011

00001100

00001 101

00001 110 00001 111

00010OOO

00010001

00010010

00010011 00010100

00010101 00010 110 00010111

00011ooO 00011 001

00

011 010

00011011

00011 100 00011 101 00011 110

00011 111 00100OOO

00 100 001

00100010

00

100 011

00100100 00100 101

00100110

00100111

00101

OOO

00101 001

00

101 010

00101 011 00101 100

00 101 101

00

101 110

00101 111

00110000

00

110001

00110010

00

110011

00110100

00110101

00110110

00110111

00lllooo

00111 001

00

111 010

00111 011

00111 100

00

111 101 00111 110 00111

111

Odal

OOO

001 002

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

05

052 053

054

055 056 057

060 061 062 063

064

065 066 067

070 071 072 073

074 075 076 077

nble

1

3-9.

-

Oscimal

-

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

-

Commonly- Used Code Conversions

Hex*

declmrl

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

18

1c 10 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

30 3E 3F

1

0

E

F

G

H

I

J

K

L

M

N

0

P

0

R

s

1

u

v

w

x

Y

2

1

\

1

-

'

a

b

c

d

e

f

g

h

i

j

k

I

m

n

0

p

q

r

s

t

u

v

w

x

y

2

!

,i,

01 OOOoo1 01

OOO

010

01 oO0011

01ooo100 01 O00101 01 OOO110

01 OOO111 01001OOO

01 001 001 01 001 010 01 001 011

01001100 01 001 101 01 001 110 01 001 111

01

010ooo

01 010001 01 010010 01 010011

01 010100 01 010101 01 010110 01 010 111

01 011

ooo

01 011 001 01 011 010 01 011 011

01 011 100 01 011 101 01 011 110 01 011 111

01 100M)o 01100001 01 100010 01 100011

01100100 01 100101 01 100 110 01 100111

01 101

OOO

01 101 001

01 101 010

01 101 011

01 101

100 01 101 101 01 101 110 01 101 111

01 110000 01 llOMI1 01 110010 01 110011

01 110100 01 110 101 01 110110 01 110111

01 111000 01 111001 01 111 010 01 111011

01 111 100

1

01 111 101 01 111 110 01 111 111

Octal

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

1 73

174

175

176

177

Decimal

64

65 66 67

68

69 70 71

72 73 74 75

77

76

79

78

80

81 82 83

84

85 86 87

88

89

90

91 92

93

94

95 96

97

98

99

101

loo

102 103

'04

105 106 107

log

110 111

112 113 114 115

116 117 118 119

120 121 122 123

124

li5

126

I

127

I

Hexa-

decimal

40 41 42

43 44

45 46 47

48 49

4A 48

4c 4D 4E 4F

50

51 52 53

54

55

56

57 58

59

5A 58

5c 50 5E

5F

60 61

62

63 64

65 66 67

68 69

6A

6B 6C

6D

6E

6F

70

71

72

73

74 75 76 77

78 79 7A 78

7c

2

7F

3-41

Operation Model

AC

Level

DESCRIPTION

8903B

The Audio Analyzer contains a wideband, true accuracy and sensitivity. The AC LEVEL key causes the Audio Analyzer voltage between its HIGH and LOW INPUT connectors. Signals that are common

and

LOW

PROCEDURE

To make an ac level measurement, press the AC LEVEL key. AC level results can be displayed mV, dBm into up displaying ac level in linear units (mV milliwatt into a simply press the LOG/LIN key again. If the ac level

RATIO

EXAMPLE

To measure the ac level of a signal at the INPUT jacks:

LOCAL

(keystrokes)

i--

(program

connectors are rejected.

600R,

watts,

or

600R

load, equivalent to are 0.775V), press the LOG/LIN key. To return

and

LOGILIN

codes)

.

as the ratio to

or

rms,

an

entered

V).

To

Measurement

or

obtain a display in dBm (that is,

is

to be displayed relative

M1

T

and average-responding voltmeter with high

to

measure the differential ac

to

both the HIGH

in

V,

measured value. The Audio Analyzer powers

dB

relative to

to

linear,

to

a reference, refer to

-,

1

PROGRAM CODE

a

I

N

D

M1

is

the program code

I

CAT1 ON

S

When ac level

ac level with the appropriate units. The Audio Analyzer automatically ranges for maximum resolution

and accuracy. The left display shows the input signal frequency.

counter is too small, the left display will show

the stop band

is

selected, the

of

the optional high-pass

for

MEASUREMENT TECHNIQUE

In ac level the Audio Analyzer acts as an ac voltmeter. The Audio 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 detector converts the ac level to a dc voltage which

is

then measured by the dc voltmeter. After correcting input gain and attenuation, the signal level

displayed in appropriate units. The frequency of the input signal level is also measured and displayed.

3-42

AC Level

AC LEVEL.

LED

within the AC LEVEL key will light. The right display shows the

If

the input level to the frequency

0.000

kHz. (This will often occur when the signal is in

or

weighting bandpass filters, but not the low-pass filters.)

is

Model

COMMENTS

8903B

__

INTERNAL

rnI

rL""

INPUT FILTERS

ATTENUATOR

AMPLIFIER GAIN AMPLIFIER GAIN AMPLIFIER

HP/BP RMS/AVG VOLTMETER/

AC Level Measurement Block Diagram

IIC-TLI

*8.

PROGRAMABLE

e

COUNTER/

LEFT DISPLAY

[FREQUENCY)

OUTPUT

DETECTOR RIGHT DISPLAY

-

(AMPLITUDE)

Operation

-

----

.

-1

,OR_

J

I

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

activated. The

Detector Selection

Display Level in Watts Filters Monitor RATIO and Special Functions

80

THE INPUT SIGNAL IS NOT TO EXCEED

RESPECT TO GROUND OR DIFFERENTIAL). Some input signal limitations apply to the level of common-mode signals.

See the

rms

SECTIONS

LOG/LIN

kHz

low-pass filter reduces the measurement bandwidth from

300V

Common Mode

Detector Selection

detailed operating instruction

NOTE

section for more detailed information concerning

and average detecting.

(EITHER

for

details.

80

kHz

750

WITH

low-pass filter

kHz

to

80

kHz.

AC Level

3-43

Operation Model

Amplitude

DESCRIPTION

8903B

The Audio Analyzer contains a low-distortion audio source. The AMPTD key, the numeric the unit keys are used to program the output level V, mV, amplitude entered AMPTD key is also used to display the currently programmed output level. The amplitude range is 0.6 mV to 6V. The maximum resolution is better than

PROCEDURE

To

set the source output level press the AMPTD key and then the appropriate numeric keys. Once the AMPTD key has been pressed, new amplitudes until another source function key (for example, the currently programmed amplitude press and hold the AMPTD key.

EXAMPLE

To set the source output level to

LOCAL

(keystrokes)

lay

(program

or

dBm

codes)

of

the source. The source level can be entered in

(that

is,

dB

relative

is

the open-circuit value. The output impedance can be either 6000

1.W:

to

1

milliwatt into a 600R load, equivalent

0.3%.

data

and unit entries

FREQ

Function-,-

Function

3

Data-r

AP1.5VL

7

Data

Unit

can

key)

Unit

be made

is

I

data

and

to

dBre 0.775V). The

or

50R. The

data

and

unit

to

select different

pressed. To display the

PROGRAM CODE

a

I N D

3-44

AP

is the program code

I

CAT1

ON

S

When the AMPTD key is pressed, the right display shows the currently programmed output level. the new output level data the left display returns to show the input signal frequency. When the amplitude is set to zero but the oscillator remains on.

Amplitude

for

the AMPTD key.

is

entered, it will appear on the

left

display. When the units key

is

set

is

pressed,

to

OV, the output

As

Model

8903B

COMMENTS

Operation

The Audio Analyzer powers up with the source frequency set

When the source output necessarily selected output attenuation level. For minimum noise, first select

When the amplitude. value which can differ from the actual value at the OUTPUT. For example, when the source output impedance value.

AMPTD

It

is

6000,

RELATED SECTIONS

Display Source Settings F'requenc Increment Output Impedance

y

NOTE

is

set to OV, maximum output attenuation

(to

minimize wear

is

not selected, then noise

6

key

is

pressed and held, the right display shows the currently programmed

important

the voltage developed across an external

to

realize

that

the value shown in the right display

to

1

kHz and amplitude set

is

not

on

the output attenuator).

is

not held to a minimum

If

full

mV source output, then select OV.

is

the programmed

6000

load

will

be

half the programmed

at

OV.

Amplitude

3-45

Operation Model 8903B

DESCRIPTION

The AUTOMATIC OPERATION key sets the instrument functions to automatic (that is, each function is allowed to automatically range to the appropriate setting). SPCL key light.

PROCEDURE

To set the Audio Analyzer to automatic operation, press the AUTOMATIC OPERATION key.

EXAMPLE

To set the Audio Analyzer to automatic operation:

LOCAL

(keystrokes)

(program codes)

Automatic

Operation

It

AUTOMATIC

OPERATION

0

AU

7-

Function

also cancels all functions that light the

PROGRAM CODE

AU

is

the HP-IB code for AUTOMATIC OPERATION.

I

N D I

CAT1

0

N

S

When the key the display

is

dependent upon the current measurement mode and input.

COMMENTS

If the Audio Analyzer to the ac level measurement mode.

The converse of the automatic operation mode

Hold

to

For

key, refer to good practice to place the instrument.

Settings.

information on which specific Special Functions are turned

Special &nctions.

RELATED SECTIONS

Display Source Settings Hold Settings Special F’unctions

pressed, the right display blanks and then

is

in the

10.0

Special Function (Display Source Settings), the instrument returns

is

the Hold Settings Special Function (prefixed

Since AUTOMATIC OPERATION affects Special hnctions, it is a

AU

code at the beginning of a program string when programming the

shows

four dashes. When the key

off

by the AUTOMATIC OPERATION

is

released,

9).

Refer

3-46

Automatic Operation

Model

8903B

Operation

DESCRIPTION

Common-mode rejection ratio, of an amplifier signal (which may circuitry.

Since the analyzer input LOW inputs (with the INPUT FLOAT switch in the FLOAT position). However, for valid measurement

results, there are limitations

~~~~ ~ ~~ ~~

Common

or

”common-mode” as it

to

reject signals that are common

or

may not be the weaker signal)

is

fully balanced,

to

the maximum level of common-mode signals.

HIGH INPUT ATTENUATOR

HIGH

INPUT

Low

INPUT

pJ

Low

INPUT

ATTENUATOR

to

it

can reject signals which are common

OVER-VOLTAGE

PROTECTION

OVER-VOLTAGE

Mode

is

usually referred

both amplifier inputs while allowing the differential

to

be amplified and passed on to the measurement

DIFFERENTIAL-TO-

SINGLE-ENDED CONVERTER

to,

is

a measure of the ability

to

the HIGH and

TO

PROGRAUUABLE

GAIN AUPLIFIER

Common-mode signal limitations exist because the instrument’s ranging detector (which determines the input voltage range), inputs). Thus, the instrument can set an incorrect input range Erroneous measurements may be obtained

The block diagram above illustrates that the ranging detector senses the voltage difference between the differential signals are measured. The block diagram lines have over-voltage protection circuits

common-mode and differential) exceeds

EXAMPLE

If

detector selects the 1.19V range. The signal that mode signal 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. (Selecting Special Function set the input range to 11.9V.)

is

HIGH

and LOW input lines. Common-mode signals are “ignored” by the ranging detector, while

a common-mode signal of

+

the

1V

differential signal). A voltage signal this large can exceed the input amplifier’s

Analyzer Input Block Diagram

designed

to

read only the

as

a result.

differential

also

that open when the input voltage (differential,

300V.

1OV

is on the analyzer’s inputs with a

is

present on each input

signal (between the high and low

if

a large common-mode signal is present.

illustrates

that

the

HIGH

and LOW input

or

1V

differential signal, the ranging

is

actually

11V

(1OV

combined

common-

1.8

will

Common Mode

3-47

Operation Model

COMMENTS

For

error-free measurements, the

indicate the maximum allowable common-mode input voltages

1

is

Case

for

To

for

For

mode input voltage level input voltage level is

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

a balanced source with common-mode signals obtain the maximum common-mode input voltage level from the graphs, select the desired value

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

example,

on

the Case 1 graph,

is

2.8V.

60V.

Operating Region

for

a differential input voltage level of

For

a differential input voltage

For

Valid Measurement

on

both input lines.

graphs, shown below,

for

a given differential input voltage.

on

both input lines. Case 2 is

lV,

the

of

maximum

60V,

the maximum common-mode

common-

8903B

3-48

?

Common

Mode

DIFFERENTIAL

INPUT

VOLTAQE

Model

8903B

DIFFERENTIAL

INPUT

VOLTAGE

Operation

DC

SECTIONS

Level

CASE

2.

Balanced Source

with

Common Mode on

Both

Sides

Common

Mode

3-49

-

Operation

DESCRIPTION

The DC LEVEL key causes the Audio Analyzer and LOW INPUT connectors. Signals that are common to both the HIGH and LOW connectors are rejected.

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,

into

soon).

the LOG/LIN again.

LOG/LIN.

EXAMPLE

To

measure the dc level at the INPUT connectors:

or,

if

DC

Level

the voltage

Model

to

measure the differential dc voltage between its HIGH

is

positive, in dBm (that is,

dB

relative to 1 milliwatt

8903B

To obtain a display in dBm, press the LOG/LIN key. To return to linear, simply press

If

the

dc

level

is

to

be displayed relative to a reference level, refer to RATIO and

LOCAL

(keystrokes)

(program

codes)

PROGRAM CODE

a

S1

is

the HP-IB code

for

INDICATIONS

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 Audio Analyzer automatically ranges

for

maximum resolution and accuracy. In the dc level measurement mode the left display

even though an ac signal may be present.

MEASUREMENT TECHNIQUE

In the dc level measurement mode the Audio Analyzer automatically sets the input attenuation and the

of

gain The signal displayed in appropriate units.

the input amplifier

is

then measured by the dc voltmeter and after correction for input gain and attenuation,

DC

s

LEVEL

s1

T

Measurement

DC LEVEL.

so

that the signal amplitude lies within the proper range of the

is

blanked

dc

voltmeter.

3-50

DC

Level

I

DC

INPUT

ATTENUATOR (AMPLITUDE)

I

AMPLIFIER

Level Measurement

Block

VOLT

l4ETE

ATGHT

OISPLAY

Diagram

R/

1

I

Model

8903B

COMMENTS

Operation

THE INPUT SIGNAL

GROUND OR DIFFERENTIAL).

Some input signal limitations apply to the size See the

In the dc level measurement mode only the ac component MONITOR output. The

RELATED SECTIONS

Common Mode RATIO and LOG/LIN Special bctions

Common-Mode

ac

component

IS

NOT

TO

EXCEED

300V

(WITH RESPECT

of

the common-mode signals.

detailed operating instruction

of

also

affects the input

gain.

for

details.

the input signal

TO

is

coupled to the

DC

Level

3-51

Operation Model

Default Conditions and Power-up Sequence

DESCRIPTION

When first turned on, the Audio Analyzer performs a sequence of internal checks after which the

is

instrument light to allow the operator to determine sequence is completed and the Audio Analyzer

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

if

any are defective. After approximately four seconds, this

is

preset as follows:

8903B

START FREQ.. STOP FREQ PLOT LIMIT

LOWER LIMIT

UPPER LIMIT.. FREQ FREQ INCR AMPTD AMPTD INCR

MEASUREMENT.. DETECTOR LP FILTER.. HPPeighting BP Filter RATIO

LOG/LIN Left Display Right Display.. Source Output Impedance Service Request Condition Status Byte Trigger Mode.. SPCL Plotter.

X

PEN

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

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

Ratio Reference

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

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

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

AXIS, Y AXIS

LIFT..

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

AC LEVEL

LOW PASS

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

Input F'requency

Input AC Level

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

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

.All Special Functions OFF

HP-IB Code Error Only

.Free Run (Code

or

in their zero suffix2

TTL high

.20

Hz

20

khZ

-100.0

.lOO.O

1000.0 Hz

.lOOO.O

0.00

mV

0.1OOV

RMS

80

kHz

Off

0

LIN'

.600R

.Cleared

TO)

Enable

OV

RELATED SECTIONS

RATIO and LOG/LIN Service Request Condition

1

See

RATIO

and

LOGILIN

2

Except Service Request Condition

3-52

Default Conditions and Power-up Sequence

Detailed Operation Sections.

The two Ront-Panel

which

is

set

to

22.2

(HP-IB

NOTE

FLOAT

Code Error)

switches are set manually.

Model

8903B

DESCRIPTION

The Audio Analyzer contains a high accuracy, wide-band, voltmeter with three types of detectors; true rms, average-responding, and quasi-peak.

PROCEDURE

Operation

Detector Selection

To select the true detection.

To

select the Average Detector, press

detection. To select the Quasi-peak Detector press

EXAMPLE

PROGRAM CODES

e

I

N

D I CAT1 ON

A0

is

the HP-IB code for RMS Detector.

Detector HP-IB program code

S

RMS

Detector press

I I

Detector

rms

average

quasi-peak

is

5.7

5.0

SPCL for

5.2

SPCL for fast average detection,

5.7

SPCL for quasi-peak detection.

Special Function

Code

5.0 SPCL

5.2

SPCL

5.7 SPCL

A1

is the HP-IB code for Average Detector. The Quasi-peak

fast

rms

I

SP.

detection,

Program

e

A0

or

A1

or

5.7SP

or

5.1

SPCL for slow

or

5.3

SPCL for slow average

Code

5.0SP

5.2SP

I

rms

When default at power up. When has been selected (slow

When detection)

5.0

SPCL is entered, there

rms

5.2

SPCL (fast average detection),

is

entered, the SPCL key light is lit to indicate a special function has been selected.

MEASUREMENT TECHNIQUE

When measuring complex waveforms measurement result than an average-responding detector that has been calibrated to indicate the value.

For

a sine wave, both the true rms and the average-responding detectors give correct However, when the signal responding detector reading can be in error. The amount of error depends upon the particular signal being measured.

The Quasi-peak Detector, which has a fast rise time coupled with a slow decay time is used to “capture” impulse type signals Detector, when used with the optional CCIR weighting Filter gives signal-to-noise measurement results which more accurately correlates with perceived signal-to-noise ratios.

For

noise, an average-responding detector reads low.

or

other signals (noise

is

no change in the instrument display since

5.1

SPCL

is

entered, the

detection).

5.3

or

noise, a true rms detector will provide a more accurate

is

a complex waveform,

rms

detection

SPCL

SPCL (slow rms detection),

or

waveforms with high crest factors.) The Quasi-peak

key light is lit

when significant noise

to

indicate a special function

Detector Selection

or

5.7

SPCL (quasi-peak

rms

is

present, the average-

readings.

is

the

rms

3-53

Operation

COMMENTS

Model 8903B

Many ac voltmeters employ an average-responding detector. an average-responding detector, select either special functions. One feature repetition rate

of

the Output Detector), you

the Quasi-peak Detector

of

RELATED SECTIONS

AC

Level Distortion Distortion Level SINAD Signal-to-Noise

For

5.2

SPCL

of

the Quasi-peak Detector

the measured signal decreases. Because there

will

not get meaningful measurements

for

Distortion

or

SINAD

(for fast average)

is

that the displayed response drops

measurements

those applications requiring the use

or

5.3

SPCL

(for

slow average)

as

is

only one Quasi-peak Detector

for

Distortion

is

not recommended.

or

SINAD. Using

(part

of

the

3-54

Detector Selection

HP 8903B Operation Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

SPECIFICATIONS

DESCRIPTION

General

Audio Testing

Transceiver Testing

Systems

OPTIONS

Electrical Options

Mechanical Options

HEWLETT-PACKARD INTERFACE BUS

Compatibility

Selecting the HP-IB Address

ACCESSORIES SUPPLIED

ELECTRICAL EQUIPMENT AVAILABLE

Front-to-Rear-Panel Connectors Retrofit Kit

Rear-to-Front-Panel Connectors Retrofit Kit

MECHANICAL EQUIPMENT AVAILABLE

RECOMMENDED TEST EQUIPMENT

PRINCIPLES OF OPERATION FOR SIMPLIFIED BLOCK DIAGRAM

Counter

Source

Controller

Frequency

Signal Impurities

Distortion

SINAD

Signal-to-Noise Ratio

Internal Source

Plotting

Line Voltage and Fuse Selection

General

Operating Characteristics

Operator's Maintenance

FRONT-PANEL FEATURES

REAR-PANEL FEATURES

BASIC FUNCTIONAL CHECKS

Description

Equipment

PROCEDURE

Preliminary Check

AC Level and Output Level Check

Distortion Check

SINAD Check

Signal-to-Noise Ratio Check

Description

Initial Setup

Equipment

Address Recognition

Receiving the Data Message

Local Lockout and Clear Lockout/Set Local Messages

Clear Message

Status Byte Message

Remote Mode

Local Mode

Addressing

Data Messages

Receiving the Data Message

Receiving the Clear Message

Receiving the Remote Message

Receiving the Local Lockout Message

Receiving the Clear Lockout/Set Local Message

Receiving the Pass Control Message

Sending the Require Service Message

Sending the Status Byte Message

AC Level

Amplitude

Automatic Operation

Common Mode

Default Conditions and Power-up Sequence

Detector Selection