Agilent 8901B Specifications Sheet

Agilent

Technologies, Inc. www.agilent.com

24001

E.

Mission

Liberty

take,

WA

99019

..':Pi;..

,.**:*%,

:

Agilent Technologies

Innovating

June

Dear Customer,

As of November semiconductor products, health care solutions, and chemical analysis became a new company, Agilent Technologies. Now, many Agilent Technologies.

At Agilent Technologies, we are working diligently to make this transition 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 name and logo, or a combination

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

products with the same model number are interchangeable.

the

8,2000

HP

Way

1

,

1999,

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

of your Hewlett-Packard products and services are in the care

as

of

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

of

smooth as possible for

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.aailent.com.

Sincerely,

Rebranding Team

,

HP

8901B

MODULATION ANALYZER

Operation and Calibration Manual

2314A

SERIAL

This

manual provides complete information for

struments with serial-number prefixes:

and

Above

Information for instruments with serial-number prefixes not listed

in

For additional important information about serial numbers, refer

THIS

and

all

MAJOR

the above range.

to

MANUAL”

“INSTRUMENTS

in

NUMBERS

changes that apply

rev.

28MA

Y93

changes is also provided for

COVERED

Section

Sixth

1.

Edition

to

in-

your

BY

instrum

ent.

This

material Government pursuant der the clause at DFARS 52.227-7013

Copyright@HEWLETT-PACKARD

EAST

24001

MISSION AVENUE, LIBERTY LAKE, WASHINGTON, U.S.A.

Operation Other Documents Available:

Service Manual (Volume 2,3,4) HP Part 08901-90114 Basic Operation Microfiche operation and Calibration Manual HP Part 08901-901 15 Microfiche Service Manual HP Part 08901-90116

and

Calibration Manual HP Part 08901-90113

and

Application Guide 08901-901

may

be reproduced by

to

17

the Copyright License

or

for the

(AF’R

COMPANY

U.S.

un-

1988).

1989

99019-9599

Printed in U.S.A. : May 1995

HEWLETT

Fa

PACKARD

1

Regulatory Information

(Updated March

1999)

1

Regulatory Information (Updated March

Safety Considerations

GENERAL

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

1999)

This product "Safety Requirements for Electronic Measuring Apparatus," and safe condition. This instruction documentation contains information and warnings which must be followed by the user to ensure safe operation and condition.

SAFETY EARTH GROUND

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

SAFETY

A

Indicates instrument damage can occur

A

Indicates hazardous voltages. Indicates earth (ground) terminal

WARNING

has

been designed and tested in accordance with

SYMBOLS

~~~~~

A

WARNING

practice, or the like, which, could result in personal

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

IEC

Publication

has

been supplied in

to

maintain the product in a safe

if

indicated operating limits are exceeded.

if

not correctly performed or adhered to,

injury.

Do

not proceed beyond a

WARNING

1010,

sign until the indicated conditions are fully understood and met.

a

CAUTION

A CAUTION note denotes a hazard. procedure, practice, or the like, which, if not correctly performed or adhered

to

to, could result in damage not proceed beyond an CAUTION note until the indicated conditions are fully understood and met.

or

It

calls attention

destruction of part or

to

an operation

all

of the product.

Do

2

Chapter

1

Regulatory Information

(Updated

March

1999)

Safety Considerations

WARNING

This product protective earthing ground incorporated in the power cord). The mains plug shall only be inserted

protective earth contact. Any interruption of the protective

conductor inside or outside of the product

product dangerous. Intentional interruption Whenever

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

If

this

instrument is to be energized via an auto transformer (for voltage reduction), make sure the common terminal the earth terminal of the power source.

If

this product the equipment could be impaired. This product must be used in a normal condition (in which all means

No

operator serviceable qualified personnel. covers.

for

this Instrument

is

a Safety Class I instrument (provided with a

it

is

likely that the protection has been impaired, the

is

not used

in

a socket outlet provided with a

is

likely to make the

is

prohibited.

is

connected to

as

specified, the protection provided by

for

protection are intact) only.

parts

To

prevent electrical shock, do not remove

in this product. Refer servicing to

Servicing instructions are

for

use by qualified personnel only.

To

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

so.

The opening of covers or removal of parts is likely to expose dangerous voltages. Disconnect the product from while

The power cord live for

it

is

being opened.

is

connected

5

seconds after disconnecting the plug

to

internal capacitors that

all

from

voltage sources

my

remain

its

power supply.

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

only

with

example, normal blow or time delay).

250

V

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

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

2

per

ONLY.

for

IEC

use in Installation Category

1010

and

IEC

664

respectively.

11

and

FOR

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

is

within the specified range.

Chapter

1

3

Regulatory Information (Updated March

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 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 greater than used.

Product Markings

1999)

Do

not attempt to clean internally.

of

the product must not be restricted.

If

the total power dissipated in the

800

watts, then forced convection

4"

C

for every

must

100

be

CE - the CE mark

is

a registered trademark

of

the European Community. A CE mark

accompanied by a year indicated the year the design was proven.

CSA

-

the

CSA

mark

is

a registered trademark

of

the Canadian Standards Association.

4

Chapter

1

CERTIFICATION

Hewlett-Packard Company certifies that this product met its published specifications at the time from the factory. Hewlett-Packard further certifies

that

its calibration measurements are traceable to

of

shipment

the

United States National Bureau of Standards, to the extent allowed by the Bureau’s calibration facility, and to the calibration facilities of other International Standards Organization members.

WARRANTY

This Hewlett-Packard instrument product of one year from date of shipment. During the warranty period, Hewlett-Packard Company will at its option, either repair or replace products which prove

For warranty service or repair, this product must prepay shipping charges shall pay

HP warrants that its software and firmware designated by HP for use with an instrument will execute programming instructions when properly installed on

of

all

shipping charges, duties, and taxes for products returned

the instrument, or software, or firmware will be uninterrupted or error free.

to

HP and HP shall pay shipping charges

is

warranted against defects in material and workmanship for a period

to

be defective.

be

returned

that

to

a service facility designated by HP. Buyer

to

return the product

to

HP from another country.

instrument. HP does not warrant that the operation

to

Buyer. However, Buyer

shall

its

LIMITATION OF WARRANTY

The foregoing warranty shall not apply Buyer-supplied software specifications for the product, or improper site preparation or maintenance.

or

interfacing, unauthorized modification or misuse, operation outside of the environmental

to

defects resulting from improper or inadequate maintenance

by

Buyer,

NO OTHER WARRANTY WARRANTIES

OF

IS

EXPRESSED OR IMPLED. HP SPECIFICALLY DISCLAIMS THE IMPLED

MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

EXCLUSIVE REMEDIES

THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES. HP NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT, TORT, OR ANY OTHER LEGAL THEORY.

SHALL

ASSISTANCE

Product maintenance agreements and other customer assistance agreements are available for Hewlett-Packard

products.

For

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

the back of this manual.

iii

Saftey

Considerations Model

SAFETY CONSIDERATIONS

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 APPLYING POWER

Verify that the product line voltage and the correct fuse is installed.

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

A

is necessary for the user to refer to the instruction manual (refer to Table of Contents).

f

procedure, practice, performed

jury.

Do

the indicated conditions are fully understood and met.

is

a

Safety Class I instrument (provided

is

set to match the available

or

supplied power cord

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

Indicates hazardous voltages.

Indicates earth (ground) terminal.

The WARNING sign denotes hazard. It calls attention to a

or

the like, which, if not correctly

or

adhered to, could result in personal in-

not proceed beyond a WARNING sign until

Any interruption of the protective (grounding)

conductor (inside ment) terminal will cause a potential shock hazard that could result in personal injury. (Grounding one conductor of a two conductor outlet is not sufficient protection).

Whenever it 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 is connected to the earth terminal of the power source.

Servicing instructions are for use by servicetrained personnel only. electric shock, do not perform any servicing unless qualified to do

Adjustments described in the manual are per-

formed with power supplied to the instrument

while protective covers are removed. Energy

a

available at many points may, sult

Capacitors inside the instrument may still be charged even if the instrument has been disconnected from its source of supply.

or

disconnecting the protective earth

is

likely that the protection has

in

personal injury.

or

outside the instru-

musl

To

avoid dangerous

so.

if

contacted, re-

8901B

be made

The CAUTION sign denotes a haz-

ard. It calls attention to an operating procedure, practice, correctly performed

age to or destruction of part

not proceed beyond a CAUTION sign until the indi-

cated conditions are fully understood and met.

iv

or

adhered to, could result in dam-

or

the like, which, if not

or

all

of

the product.

Do

For

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

ple, normal

repaired fuses

fuseholders.

blow,

time delay, etc.).

or

short circuited

250V

Do

fuse(s)

not use

Model

8901B

Saftey Considerations

ATTENTION

Static Sensitive

Devices

This instrument was constructed charge) protected environment. conductor devices used in this instrument are susceptible to damage by static discharge.

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

These charges are generated in numerous ways such 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 darnage

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

destroyed

or

immediate destruction.

or

destruction.

in

Section VIII Service Section.

by

servicing equipment containing static sensitive

in

This

contact

an ESD (electro-static dis-

is

because most of the semi-

or

mere proximity of a static

as

simple con-

FOR

STATIC SENSITIVE

V

Model

8901B

Contents

CONTENTS

Section

Introduction

Operation and Calibration Manual

Service Manual Specifications Safety Considerations Recommended Test Equipment Instniments Covered

Options

SerialNumbe

Documentation Updating

A

Description

Signing Up for the Documentation Update Service

Hewlett-Packard Interface Bus (HP-IB)

Compatibility. Selecting the HP-IB Address

Additional Equipment Information

Options Accessories Supplied Electrical Equipment Available Mechanical Equipment Available

Description

RF

RF Fkequency Measurements Modulation Measurements Filters, De-emphasis Networks and Modulation Calibrators Additional Features Specialhctions Extending Measurement Range Programmability

Principles

RF Circuitry LOCircuitry IFCircuitry

Audio Circuitry

Modulation Basics

Amplitude Modulation Exponential Modulation Other Considerations

to

This Manual

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

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

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

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

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

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

by

This Manual

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

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

rs

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

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

of

the Manual Update Packet

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

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

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

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

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

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

of

the Modulation Analyzer

Power Measurements

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

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

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

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

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

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

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

of

Operation Using A Simplified Block

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

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

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

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

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

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

1

.

General Information

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

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

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

Diagram

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

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

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

1-1

1.1 1-1

1.2

1-2

. 1-2 . 1-2 . 1-3

. 1-3

. 1-3 . 1-3

1-3 1-3 1-4

. 1-4 . 1-5

1-6

. 1-6 . 1-7 . 1-7

1-7

. 1-7

1-8

. 1-8

1-8

1-9

1-11 1-11 1-11

1-12

1-15 1-17

vii

Contents Model 8901B

Section

Introduction Initial Inspection

Preparation for Use

Power Requirements Power Cables Line Voltage and Fuse Selection

HP-IB Address Selection Interconnections Mating Connectors Operating Environment Bench Mounting

RackMounting

Removal and Installation

Storage and Shipment

Environment Packaging

to

This Section

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

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

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

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

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

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

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

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

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

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

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

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

of

Operating Information Pull-Out Cards

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

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

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

Section

Introduction

Local

Remote Operation Section Basic finctional Checks Section Detailed Operating Instructions Section Other Sources of Operating Information

Operating Characteristics Operator’s Information

Fbes Time Base 10 MHz Input and Time Base 10 MHz Output

Description

Turn-On Procedure

Instrument Features

Front-Panel Features Rear-Panel Features

Remote Operation

Introduction to the Section How to Use this Section to Make a Measurement

Programming the Modulation Analyzer

Overview

Valid

Invalid Characters Programming Syntax

Code String Syntax (Sequence Dependency) Programming Examples

Reference Tables

Data Output

Data Output Format

HP-IB Information

HP-IB Capabilities HP-IB Address

to

This Section

Operation Section

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

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

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

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

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

of

the Measuring Receiver

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

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

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

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

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

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

VIA

the Hewlett-Packard Interface Bus (HP-IB)

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

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

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

Programming Codes

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

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

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

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

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

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

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

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

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

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

2

3

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

.

Installation

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

.

Operation

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

;

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

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

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

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

2.1

2.2

2.4

2.8

2-8

2.8

2.9

2.9 2-9

3.1

3.2

3.2 3-2 3-3 3-3

3-3 3-4 3-6 3-9

3-13 3-13

3-13 3-13 3-13

3-13 3-14 3-15

3-16 3-17

3-17 3-18

3-18 3-19 3-19 3-20

viii

Model

8901B

Contents

Section

Modulation Analyzer Remote Capabilities (IEEE-488)

Triggering Measurements Trigger Modes

Triggers Clear Remote/Local

Mode Descriptions Mode Transitions Local Lockout

Clear Lockout/Set Local

Service Request Message (SRQ) SRQ MASK (Special Fbnction

StatusB Abort Pass Controlflake Control Status Bit

Additional Information

Annunciators Reading the HP-IB Address Switch and

TALK and LISTEN Code Execution in the Modulation Analyzer

Basic bctional Checks of the Modulation Analyzer

Description Equipment Procedure

Basic bctional Checks

Description Initial Setup Equipment Procedures

Detailed Operating Instructions

Introduction Section Organization

How

FW

Frequency Measurements (RF, LO. Modulation Measurements Contents

Audio Measurements Contents Additional Capabilities Contents

(T2.

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

yte

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

to

Find Information About a Specific Measurement

Power and Level Contents

(TO

and

T3.

GET. and the CLEAR Key)

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

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

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

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

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

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

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

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

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

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

to

This Section

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

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

T1)

........................................... 3-26

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

22)

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

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

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

Status

of

Descriptions

the Hewlett-Packard Interface Bus (HP-IB)

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

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

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

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

IF)

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

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

3

.

Operation (cont’d)

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

SRQ

Status

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

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

Contents

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

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

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

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

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

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

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

3-20 3-21

3-22 3-23 3-24

3-25 3-25 3-25

3-25

3-26 3-29

3-31 3-32 3-32 3-32 3-32

3-32

3-33

3-34

3-47 3-47

3-47 3-47 3-56 3-56 3-57 3-57 3-57

3-67 3-67

3-69

3-109 3-133

3-197 3-205

Introduction Equipment Required Performance Test Record Calibration Cycle Abbreviated Performance

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

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

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

Section

4

.

Performance Tests

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

Testing

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

4.1

ix

Contents

Model

8901B

Performance Test Performance Test

Performance Performance Test

Performance Test Performance Test

Performance Performance Test Record

1

.

AM

2

.

FM

3

.

cPM

4 . Audio Filters

Test

5 . Audio Measurements

6 . Power Reference (Using Reference Comparison

7

.

Power Reference (Using DC Substitution)

8

.

Power Meter

9

.

SWR

10 . High-Selectivity (Options

Test

11

.

High-Selectivity Gain (Option Series

Section

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

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

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

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

4

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

Section

Introduction

Safety Considerations Wipment Required F'actory-Selected Components Post-Repair Tests, Adjustments, and Checks Related Adjustments Adjustment Adjustment

Adjustment Adjustment

Adjustment

Adjustment Adjustment

Adjustment

Adjustment Adjustment

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

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

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

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

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

1

.

Power Supply

2 . Internal Reference

3

.

RF Level Detector Offset

4 . Sampler Efficiency and Offset

5

.

LO

Doubler Output Power and Balance

6

.

Voltmeter Offset

7

.

15

kHz

and

8

.

ALC

Reference

9

.

FM Calibrator

10 . FM Sensitivity

11

.

FM Flatness

12 . FM Distortion and Incidental 13 . cPM Sensitivity

14

.

AM

Calibrator

15

.

AM

16 . FM Distortion and Incidental AM . 455 17 . Tkack-The Mode Offset

18 . Power Reference (Using Reference Comparison 19 . Power Reference (Using DC Substitution

20 . Power Meter

21

22 . Battery Backup

Sensitivity

.

Audio True RMS Detector and Notch

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

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

and

>20

Sensitivity

kHz

Low-Pass Filter Gain

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

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

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

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

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

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

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

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

.

Performance Tests (cont'd)

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

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

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

032

and

033)

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

030)

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

5

.

Adjustments

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

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

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

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

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

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

AM

.

1.5

MHz

IF'

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

kHz

IF

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

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

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

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

Filter

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

Gain

4.2

4.8

4-14 4-18

4-20 4-25

4-26 4-29

4-31 4-33

4-38 4-40

5.1

5.2

5.5

5.6

5.7

5.8

5-10 5-12

5-14 5-15

5-16 5-17

5-18 5-19

5-21 5-23

5-24 5-25

5-27 5-28

5-30 5-33

5-35 5-37

X

General

Information

Model

8901B

MODEL

LINE POWER CABLE

8901B

1-0

Figure

1-1.

HP

8901B

Modulation Analyzer and Supplied Accessories

Model 8901B General Information

GENERAL INFORMATION

1-1.

INTRODUCTION TO THIS MANUAL

The HP 8901B and the three volume install, operate,

The information

5

are contained in this

Application Guide)

Service Manual Service Manual Request Card

The Modulation Analyzer Modulation Analyzers supplied with Options 001,002,003,004, and series 030.

Operation and Calibration Manual

Section

instrument description, options, accessories, specifications and other basic information. This section

also

1,

contains instrument theory of operation on a simplified block diagram level.

Operating and Service Manual

Service Manual.

test,

adjust, and service the Hewlett-Packard Model 8901B Modulation Analyzer.

to

operate and service this instrument

Operation and Calibration Manual

which is provided with each instrument. Sections 6 through 8 are contained in the

that

is

not included with the instrument but which can be obtained by mailing in the

is

General Information

Section

These four volumes contain

included in this manual.

shown in Figure

describes the instruments documented by this manual and covers

1-1

1

is comprised of an

is

made available

with all supplied accessories. These manuals document

Operation and Calibration Manual

all

the information required

as

follows: Sections 1 through

(that includes the

Basic Operation and

to

Section

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

Section

operating instructions for both local and remote operation.

Section

instrument against the critical specifications in Table

Section

2,

Installation

3,

Operation

4,

Performance Tests

5,

Adjustments

provides information about panel features and includes operating checks, and

provides information about initial inspection, preparation for use (including

provides the information required

1-1.

provides the information required

to

properly adjust the instrument.

to

check performance of the

Service Manual

Section

tion information.

Section

Additional copies of the separately through your nearest Hewlett-Packard office. The part numbers are listed on the title page of this manual.

6,

Replaceable Parts

7,

Instrument Changes

8,

Service

provides the information required

provides ordering information for

provides backdating information, and retrofitting and modifica-

to

repair the instrument.

Operation and Calibration Manual

all

or the

replaceable parts and assemblies.

Service Manual

can be ordered

1-1

General Information Model 8901B

1-2.

SPECIFICATIONS

Instrwnent specifications are listed in Table

against which the

acteristics,

information for the user.

1-3.

SAFETY CONSIDERATIONS

This product is a Safety Class I instrument (that is, provided with a protective earth terminal). The Modulation Analyzer safety markings the beginning of

Safety information pertinent adjustment

1-4.

RECOMMENDED TEST EQUIPMENT

Table and servicing the Modulation Analyzer. instruments with equivalent minimum specifications may be substituted. Table 1-2 also includes some alternate equipment listings. Table 1-3 lists those contained in the Service Accessory Kit, HP 08901-60287.

1-5.

INSTRUMENTS COVERED

are not warranted specifications but are typical characteristics included as additional

and

this

or

service) is found throughout these manuals.

1-2

lists the test equipment

1-1.

instrum

ent may be tested. Information listed in this table as

and

all related documentation

instructions before operation. Refer

manual for a

summary

to

the task at hand

and

accessories recommended for use in testing, adjusting,

If

BY

THIS MANUAL

of the safety information.

any of the recommended equipment is unavailable,

These are the performance standards,

Supplemental

must

be reviewed for familiarization with

to

the

Safety

(installation,

a

number of accessories required in addition

Considerations

operation, performance testing,

page found at

or

limits,

Char-

to

Opt

ions

Electrical options 001,002,003,004, series 030, and various mechanical options these manuals. The differences are noted under paragraph 1-8,

Parts,

Serial Numbers

Attached The fist four digits that is unique having the same serial number prefix(es) as listed under SERIAL NUMBERS on the respective manual title pages.

For information concerning a serial number prefix not listed on the title page Changes supplement, contact

1-6.

MANUAL UPDATING

This manual may be revised as needed changes. The latest revision shown below.

are

documented in

Options,

and in the schematic diagrams in Section 8.

to

the instrument is a serial number plate. The serial number is in the form 1234A00123.

and

the letter are the serial prefix. The last five digits form the sequential

to

each instrument. The contents

your

nearest Hewlett-Packard office.

to

make corrections and

of

the manual

of

these manuals apply directly

to

document hardware and firmware

can

be purchased from the Hewlett-Packard locations

in Table 6-3,

to

or

in the Manual

Replaceable

suffix

instruments

1-2

rev.28MA

Y93

Model 8901B General Information

Inside the U.S.A.

Call

HP Parts Direct Ordering

available.

at 800-227-8164. They can

also

help determine

if

a new revision is

Outside the U.S.A.

Contact the local Hewlett-Packard Sales and Service office for ordering information.

1-7.

HEWLETT-PACKARD INTERFACE BUS (HP-IB)

Corn pati bil ity

The Modulation Analyzer’s capabilities are defmed by the following interface functions: SH1, AH1, T5, TEO, via open-collector Standard 488- 1978, the identical ANSI Standard

For

Remote Operation, Hewlett-Packard Interface

Selecting the

The HP-IB address switches five-bit binary number. This number represents the talk and listen address characters which the controller talk only

HP-IB Address Selection

1-8.

ADDITIONAL EQUIPMENT INFORMATION

0

pt i ons

Options are variations on the standard instrument which can be ordered during the purchase. The following list defines all currently available options. Refer section for retrofit part numbers

L3, LEO,

SR1, RL1, PPO, DC1,

TTL

circuitry.

An

IEEE Standard and Digital Interface for Programmable Instrumentation

MC

1.1.

more detailed informationrelating

HP-IB

must

or

to

Address

are

located within the Modulation Analyzer. The switches represent a

generate.

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

In

addition,

in Section 2 of this

that

DT1,

CO.

The Modulation

explanation of the compatibility code may be found in

to

programmable control

Bus

in Section 3 of this

two

more switches allow the Modulation Analyzer

Operation and Calibration

to

can be ordered after the purchase.

Analyzer

of

the Modulation Analyzer, refer

Operating Information

interfaces with the bus

manual.

to

be set

Electrical Equipment Available

IEEE

or

to

to to

in this

rev.

Option

PUT, SENSOR input, MODULATION OUTPUT/AUDIO INPUT, and CALIBRATION OUTPUTS.

Option

place of the standard reference oscillator. rear panel.

28MA

Y93

001.

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

002.

This option provides a high-stability

In

addition, a

(1

x

10-g/day) internal reference oscillator in

10

AMYFM

MHz time base output

and

RF

POWER

is

provided on the

IN-

1-3

General Information Model

8901B

Option

for an external local oscillator signal. Both connections are located on the rear panel.

provided automatically with option

Option

at frequencies greater than

Option

sideband carrier noise output for the internal local oscillator and an input for an external local oscillator signal with these options.) This option

Options

Option

the

003.

This option provides both an output for the internal local oscillator signal and an input

004.

This option allows operation at line frequencies ranging from

030.

The High Selectivity Measurement option provides the capability

Option

032.

This option provides a

033.

This option provides a

035.

This option provides a

037.

This option provides a carrier noise filter.

907-909.

910.

This option provides an extra copy of both the

Service Manual.

030

series instruments.)

66

Hz

is

restricted

(AM

or phase) quickly and accurately up

is

ordered with one of the following filter options:

These options are described in

to

12.5

kHz adjacent channel filter.

25

kHz adjacent channel filter.

30

kHz (Cellular Radio) alternate channel filter.

48

to

less than

126.5

Vac line input.

to

1.3

GHz with an external

Mechanical Equipment Available.

Operation and Calibration Manual

(This

400

Hz. Operation

to

measure single-

output

LO.

is

provided

is

(An

and

Accessories Supplied

The Accessories Supplied are pieces of equipment which are shipped automatically with every Modulation Analyzer.

Line Power Cable.

on the destination of the original shipment. Refer

Information

Fuses.

2110-0043)

of original destination. Refer

Information

manual.

Fbes with a

are supplied. One fuse

manual.

The line power cable may be supplied in several plug configurations, depending

to

2.5A

rating for

is

factory installed according

to

Line Voltage

115

Vac

Power Cables

(HP

2110-0083)

and

he Selection

in Section 2 of this

and a 1.5A

to

the voltage available in the country

in Section 2 of this

rating for

230

Electrical Equipment Available

This equipment

HP-IB Controller.

compatible computing controller or computer for automatic systems applications.

Sensor Module.

using a single input connector. Switching back and forth between the Modulation Analyzer’s SENSOR input and RF INPUT connectors happens automatically with these modules (which contain an internal switch). The HP range

50

MHz to is taken with each sensor module isolates the power sensor from the source-under-test, reducing mismatch. Microwave hardware and a selected RF input cable further improve SWR and insertion loss.

is

available

The Modulation Analyzer has an HP-IB interface and can be used with any HP-IB

The HP

11722A

26.5

to

be ordered for the Modulation Analyzer

11722A

covers the Erequency range

GHz and

and

11792A

is

intended for use with the HP

to

minimize input

after

Sensor Modules enable you

100

kHz

to

2.6

GHz; the HP

11793A

SWR

and resulting errors. A low SWR attenuator

Down

the time of sale.

to

characterize a signal

11792A

Converter. Special care

Operating

Vac (HP

Operating

covers the

1-4

Model 8901B General Information

Down Converter.

The HP 11793A Down Converter, when used with a suitable local oscillator, extends

the useful range of the Modulation Analyzer into the microwave region. Provisions have been made in

to

the Modulation Analyzer

account for the frequency of the local oscillator and provide direct display

of the frequency of the microwave input signal.

Test Source.

high rates as well adjusting the Modulation Analyzer; however,

The HP 11715A AMFM Test Source produces extremely linear AM and

as

a low-noise

CW

signal. This source

it

is

required for performance testing and

an excellent stand-alone instrument for generating

FM

at

very low-distortion FM in the broadcast band.

Service Accessory Kit.

accessories (such

Front-to-Rear-Panel Connectors Retrofit Kit (Option

as

components and full instructions for converting front-panel connections

A

Service Accessory Kit (HP 08901-60287)

is

available which contains

extender boards and cables) useful in servicing the Modulation Analyzer.

001).

This kit contains all the necessary

to

rear-panel connections.

Order HP part number 08901-60282.

Rear-to-Front-Panel Connectors Retrofit Kit (Standard).

This kit contains

all

the necessary

components and full instructions for converting Option 001 instruments with rear-panel connections

to

instruments with front-panel connections. Order

High-Stability, Internal-Reference Retrofit Kit (Option

HP

part number 08901-60283.

002).

This kit contains all the necessary components and full instructions for installation of the high-stability, internal-reference oscillator. Order HP part number 08901-60281.

Rear-Panel Local Oscillator Connections Retrofit Kit (Option

003).

This kit contains all the necessary components and full instructions for installation of rear-panel local oscillator connections. Order HP part number 08901-60280. (These connections are already included in all Option 030 Series instruments.)

Conversion to

frequencies greater than 66 Hz may be converted However, operation at line frequencies greater than 66 Hz will be restricted or equal installation, performance will be identical

400

Hz Line Operation.

to

126.5 Vac. To convert to

Modulation Analyzers not equipped

to

operate at line frequencies from 48

400

Hz operation, order HP part number 08901-60095. After

to

the HP 8901B Option 004.

to

operate at line power

to

line voltages less than

Mechanical Equipment Available

The following they were not ordered with the original shipment and are now desired, they can be ordered from the nearest Hewlett-Packard office using the appropriate part number.

Front-Handle Kit (Option

part number 5061-9690 for the basic kit and 2190-0048 for lockwashers

Rack-Flange Kit (Option

rack using the flange kit. Order HP part number 5061-9678.

Rack-Flange and Front-Handle Combination Kit (Option

a rack-flange kit packaged together; Order HP part number 5061-9684 for the basic kit and 2190-9609 for lockwashers

kits

might have been ordered and received with the Modulation Analyzer

907).

Ease of handling is increased with the front-panel handles. Order HP

(8

required).

908).

The Modulation Analyzer can be solidly mounted

909).

it

is composed of a unique part which combines both functions.

This

is

not a front-handle kit and

as

to

the instrument

(8

required).

to

440

options.

Hz.

If

1-5

General Information Model

8901B

Chassis Slide-Mount Kit.

mounted. Access to internal circuits and components

the instrument from the rack. Order HP part number

order adapters for non-HP rack enclosures, use HP

Chassis-Tilt, Slide-Mount Kit.

also allows the tilting of the instrument up

(17

in.) tilting slides. To order adapters for non-HP rack enclosures, use HP part number

1-9.

DESCRIPTION OF

The HP Model characterizing signals in the

of

four separate instruments in its ability the characteristics of the demodulated audio signal flexibility allows you a signal.

The Modulation Analyzer can measure an RF signal's frequency, frequency (broadband, and off-channel), amplitude modulation (AM), frequency modulation (FM), phase modulation (@M), and AM and FM noise components. measure the audio signal's frequency and distortion.

The Modulation Analyzer single key. The Modulation Analyzer's large digital display shows measurement results with excellent resolution and measurement results can be transferred Hewlett-Packard's implementation of

THE

8901B

is

easy

This kit

is

extremely useful when the Modulation Analyzer

or

is

the same

or

down

the rear panel

1494-0017

part

number

as

the Chassis Slide Mount Kit above except

90".

Order

for

1494-0023.)

HP

is

possible without removing

432

mm

part number

(17

in.) fixed slides. (To

1494-0025

MODULATION ANALYZER

Modulation Analyzer

150

kHz

to

make those measurements most commonly needed

is

fully automatic and all major measurements can be made by pushing a

to

read. All Modulation Analyzer operations can be controlled and

via

IEEE

is

a complete measurement system

1300

MHz frequency range. It combines the capabilities

to

measure

the Hewlett-Packard Interface

Standard

RF

power, carrier frequency, modulation and

(as

well

as

those of external audio signals). This

It

recovers the modulating signal and can

488

and ANSI Standard

to

totally characterize

drift,

Bus

(HP-IB). (HP-IB

MC1.l.)

is

for

432

1494-0023.

for

accurately

power level

rack

it

mm

all

is

RF Power Measurements

The Modulation Analyzer delivers the accuracy and resolution of a high-performance power meter.

The HP

at frequencies from

limits using other power sensors. The HP

extended measurement capability.)

Input Power Protection.

damage from the accidental application of excessive power. equipment used Protection opens and protects sensitive components, and the Modulation Analyzer displays an error message. The circuit automatically resets whenever

RF Power Calibration.

available in every instrument. Also, the front-panel ZERO function enables you module without removing it from the source-under-test. After the ZERO key offsets are stored automatically.

RF

into the Modulation Analyzer's non-volatile memory. The instrument automatically compensates for the power sensor's efficiency and mismatch loss at each frequency.

8901B,

Power Calibration Factors.

with the HP

100

kHz

to

measure transmitters.) The Modulation Analyzer is

is

provided by limiting diodes and an RF relay. When excessive power

11722A

to

2.6

Sensor Module, measures power from

GHz. (Refer

to

890lB

The Modulation Analyzer

a

key

is

depressed.

RF Power Calibration

RF Power Calibration Factors can be entered from the power sensor

is

Table

1-1,

Specifications,

also accepts all HP

is

equipped with input power protection

(This

8480

is

a common cause

tested

accomplished with the

+30

dBm

to

for specified frequencies

series power sensors

of

for inputs up

is

applied, the relay

50

MHz, 1 mW standard

to

zero the sensor

is

pressed, the new zero

-20

dBm

for

to

prevent

damage in

to

2W.

1-6

Model 8901B General Information

High Selectivity Measurements.

HP

8901B Modulation Analyzer. Used with a low-noise external

accurate single-sideband (SSB) carrier noise measurements

Options 030-037 add selective power measurement capability

LO,

the

HP

8901B performs fast,

to

1.4 GHz.

RF Frequency Measurements

In automatic operation, the Modulation Analyzer 1300 MHz frequency counter. The frequency counter automatically adjusts itself

is

changes. There Analyzer is usually used signals with significant levels of AM.

no need

to

manually set or adjust the input attenuator. Because the Modulation

to

measure modulated signals,

has

the performance

its

frequency counter

of a high-quality, 150 kHz

as

the input level

also

accurately measures

Modulation Measurements

The Modulation Analyzer has extremely low internal noise. Incidental AM, FM, and QM can be measured on a wide range of simple and complex modulated signals. To complement measurement capability, the HP 8901B characterizes audio signal level, frequency, and distortion. (These features are also available for external audio signals.)

its

Filters, De-emphasis Networks and Modulation Calibrators

Post-Detection Audio Filters.

filters

detection audio

in

combination. Their cutoff frequencies have been chosen

or

as

such overshoot for square-wave modulation measured.

transmitter or signal generator testing. The

for filtering the recovered modulation. These filters can be selected individually

The Modulation Analyzer has

>20

kHz filter

so

that this type of modulating waveform can

two

high-pass and three low-pass post-

to

match those needed for applications

is

a Bessel filter.

It

also

be accurately

to

the

to

modulation

minimizes

De-Emphasis Networks.

in

used 50, 75, and 750 You can select whether the de-emphasis network affects the deviation measured. The ability either the actual or “de-emphasized deviation” increases the usefulness of the Modulation Analyzer in many applications.

Modulation Calibrators.

measurements calibration standard. In all instruments, a precise AM and FM modulation standard

When the output of the calibrator of modulation automatically compensate measured modulation

addition

to

ps.

of

AM

is

measured to create a calibration factor. The calibration factor can be used

The Modulation Analyzer contains four de-emphasis networks

the audio filters. These are the ones commonly used

When selected, the de-emphasis networks always affect the demodulated output.

One of the most difficult problems involved in making very accurate

depth or FM deviation

is

connected

all

subsequent measurements. The calibration factor is the ratio of the

to

the internally-computed modulation of the calibrator, expressed in

is

generating a precisely modulated signal

to

the Modulation Analyzer’s input, the amount

in

FM communications-25,

is

included.

Additional Features

Tuning Features.

signal and measures it. In manual operation, you can determine the frequency

Entering the approximate frequency on the keyboard causes all but very close interfering signals eliminated. This allows the Modulation Analyzer

A track mode feature enables you to track a signal, manual tune operation.

In automatic operation, the Modulation Analyzer automatically tunes

to

which the Modulation Analyzer tunes.

to

selectively measure signals other ‘than the largest.

as

it

changes frequency, from either automatic or

to

that

can be

to

use as

7%.

the input

select

a

to

be

1-7

General Information Model 8901B

Store and Recall functions.

in non-volatile memory and recall them

Display Flexibility.

power can be displayed in watts, am, V, dBV, mV, dBmV, pV, and

LOG/LIN

the keyboard. These features eliminate the need for recalculating measurement results.

keys

The Modulation Analyzer offers numerous data-display formats. For example, RF

to

display results in

These functions enable you

as

needed.

dB

or

7%

relative

to

either a measured value or a value entered from

to

store eight complete instrument settings

dBpV.

Use

the RATIO and

Special Functions

The Modulation Analyzer can do more than accessed using the numeric keys and a Special Function key. The Special hctions provide access

to

other measurements and functions, manual control of instrument functions, instrument operation verification, and service

All

instrument functions not set using these Special Functions remain in the automatic mode. This

to

allows you key alone, the display shows ten digits that indicate which functions are in automatic and the those manually set.

There are also numerous Special Functions that can be used various sections are operating properly. These, along with service special functions, make diagnosing and repairing the Modulation Analyzer faster and easier.

Those Special Functions that are most commonly used in operating the Modulation Analyzer are described on the

select any combination of manual or automatic operations. By depressing the special

Special hnction Information

aids.

is

apparent from the front panel. Many functions

in

verifying that the instrument and

pull-out card under the front panel.

state

are

of

its

Extending Measurement Range

Operation

path. This system then functions as a single instrument making microwave modulation, frequency, power, and level measurements. You control operation from the Modulation Analyzer's front panel.

When the external controller Offset mode for your microwave power sensor.

to

42

GHz

is

LO

to

make the change. A separate, non-volatile calibration factor table

Programmability

The Modulation Analyzer

IB).

This, coupled with the diversity with which these measurements can be made, and the flexibility of the Special bctions, make the instrument ideal for systems applications. In many instances in a system, speed measurements, reduce complexity and improve accuracy.

When the Modulation Analyzer is in remote, the front-panel annunciators make determine the state the instrument is in; whether

1-10.

PRINCIPLES

The Modulation Analyzer signal the Modulation Analyzer contains an and bandpass filter, a demodulator (detector or discriminator), and audio filters (tone controls). The Modulation Analyzer, however, contains additional features which make

to

automatic tuning, selectable measurement mode: signal frequency, power level, or modulation (AM, FM, or Phase Modulation (@MI), selectable audio detector (peak, average, or audio counter,

OF

OPERATION USING

a

fixed, intermediate frequency

accomplished when an external

frequency must be changed, the Modulation Analyzer requests an external

is

completely programmable

of

measurements the Modulation Analyzer can make, the speed

A

SIMPLIFIED

is

a calibrated, superheterodyne receiver, which converts the incoming

(IF),

RF

amplifier, a local oscillator

LO

and mixer are included

via

the Hewlett-Packard Interface Bus (HP-

it

can reduce the number of instruments

it

is

in the talk, listen, or service request

which

rms

responding),

BLOCK

is

then demodulated.

DIAGRAM

(LO),

a

it

much more versatile:

in

the measurement

is

available in Frequency

it

very easy

state.

As

in a radio receiver,

mixer, an

IF'

amplifier

to

1-8

Model 8901B General Information

0

audio distortion analyzer,

0

measurement calibrators (AM, FM, or power level), and

0

HP-IB programmability.

The entire operation of the instrument sets up the instrument at turnon, interprets keyboard entries, executes changes in internal hardware, and displays measurement results and error messages. The computing capability of the Controller also used the AM or FM generated by the AM and FM Calibrators, and converts measurement results into ratios (in

RF

Circuitry

The RF input signal normally enters an external Sensor Module such Figure input connector of the Modulation Analyzer. For the RF Power measurement, the input directly into the Power Sensor, which converts the RF power absorbed by the RF Power Sensor into a low-frequency, chopped, ac voltage whose amplitude Power Meter amplifies the chopped signal and converts voltmeter. (The voltmeter includes the Audio Peak Detector, Audio Average Detector, Voltage-to-Time Converter, and Counter.) The calibration of the Power Meter can be verified by connecting the Sensor Module Power Reference Oscillator

%

to

simplify circuit operation. For example,

or

dB).

The Controller

1-2.)

For all measurements except RF Power, the Sensor Module routes the signal

to

the CALIBRATION

also

is

an accurate 1 mW reference.)

The Power Sensor sudden, large overloads. Refer to Table Characteristics, RF Power Ranges of HP

HP

11

722A

Sensor Module,

is

governed by a microprocessor-based Controller. The Controller

it

forms the last stage of the Counter, calculates

contains routines useful for servicing the instrument.

as

an HP 11722A. (See

signal

is

proportional

it

to

a

dc voltage which

RF

POWER OUTPUT connector on the front panel. (The 50 MHz

is

unprotected against and

1-1

under RF Power, Supplemental

8901B

for

information on maximum operating lemls.

Modulation Analyzer with

to

the average RF power. The

is

easily damaged

is

then measured by the

by

to

the

passes

is

FW

When the RF Peak Detector senses that the input signal level exceeds lW,

Relay. This

by the voltmeter, The Input Mixer converts the input signal

than 10 MHz, the

frequency; an IF of 455 kHz can be manually selected for this frequency range. The 455 kHz selected automatically for input signals between 2.5 MHz and 10 MHz. Below 2.5 MHz, the input

passes directly through the Input Mixer without down-conversion.

The instrument can be manually tuned filtering may be necessary since low-frequency signals pass directly into the Filter can be inserted (via a Special Function)

To measure the input frequency, the Counter measures the frequency of the LO and the frequency of the difference between the which equals the input frequency.

is

done without intervention of the Controller. The output from the

is

used

to

set the Input Attenuator

to

the intermediate frequency

IF

is

1.5

MHz with the Local Oscillator

For

the input signal to pass through the Input Mixer without down-

conversion, the

LO

frequency of respond to input frequencies between

IF

from the output of the IF Amplifier and Filter. The Controller computes and displays the

150

LO

must still be present to turn the mixer

101.5

MHz

is

arbitrarily used. Thus the instrument will

of

kHz

and

2.5

MHz.

to

a desired signal even in the presence of larger signals, although

two

frequencies. For input frequencies below 2.5 MHz, only the

to

optimize the level applied

(LO)

tuned

NOTE

100

or

103

MHz

as

well

in

the RF path for this purpose.

it

opens the Overpower

RF

Peak Detector, read

to

the Input Mixer.

(IF).

For frequencies greater

1.5

MHz above the input

diodes

as

on. An

frequencies

IF.

The

RF

IF

is

High-Pass

is counted,

1-9

w w

0

I

SWITCH

MODULATION

lNPU1

POWER

SENSOR

ANALYZER

OVERPOWER RF

POWER

PO!!!

POWER REFERENCE

OSCILLATOR

INPUT

tNPUl

HP

'I

I

2,

-1

kHI

e.~

OR

2.5

Ynz

LP

FILTER OEYOOULAlOR

CI-

CI

-

CI-

L1

IF

AM

OR

I

IF

PEAK

OElECTOR

II

I

AUDIO

FILTERS

AND

6A1N CONTROL

I

CHANNEL FILTERS OElECTOR

iopiiow

'DP!!?!!

SERIES

IF

030

O!.!".

ONLY)

RYS

\

OlSlORTlON

I I

COUNlER

AUOlO

OElEClOR

AUDIO

DETECTOR

AUOIO

AV6

PEAK

AUDIO

RYS

WIDE

,

455

Model

8901B

LO

Circuitry

The

LO

drives the high-level port of the Input Mixer and

has

four main modes of operation:

a

tuning keyboard (manual tune mode),

a

automatically searching for an input signal, then tuning the LO down-convert the signal (automatic tune mode),

a

automatically searching for an input signal, then configuring the automatically tracks the signal (automatic tune track mode), and

a

tuning keyboard, then configuring the LO in a feedback loop

(manual tune track mode).

to

the frequency required to down-convert a signal whose frequency

to

the frequency required

to

down-convert a signal whose frequency

is

one of several inputs

that

automatically tracks the input signal

General Information

to

the Counter. The

is

entered from the

to

the frequency required

LO

in

a feedback loop that

is

entered from the

to

The manual tune track mode of other signals. The non-track modes are used when the

IF

Circuitry

The gain of the

1.5

the nominal center frequency

455

In instruments with Option Series

also include Filters set the by entering a series of Special Functions which establish Filter, then allow the relative offset.

MHz

kHz Bandpass Filter (with a bandwidth of

IF

Amplifier

IF

is

selected, the

a

precision, variable-gain amplifier) and detected by the

IF

bandwidth and gain for the Selective Power measurement. The measurement

is

fixed. The

of

1.5

IF

useful when

IF

Filters determine the frequency response of the

IF

filter consists of a 150

MHz). When the

030,

the

IF

level

to

be displayed

Audio Circuitry

The modulation on the

is

recovered

The demodulated signal

filters processed signal and the voltmeter.

by

integrating the demodulated FM in the Audio

are

selected from the front panel, and for FM, the filtering may also include de-emphasis. The

is

passed

IF

is demodulated by either the AM or the FM Demodulator. Phase modulation

is

amplified and filtered in the Audio

to

the front-panel MODULATION OUTPUT/AUDIO INPUT connector

it

is

desired to follow an unstable signal in the presence

LO

noise (residual FM) must be minimized.

kHz

to

2.5

MHz bandpass filter (with a

455

kHz

IF

is

200

signal

selected, the

kHz).

is

further processed by the Channel Filters (which

IF

RMS Detector. The Channel

an

IF

reference in the center of the Channel

as

the

IF

frequency

Filters

is

detuned

and Gain Control circuitry.

and Gain Control circuitry. The

IF

filter

by

a

pre-determined

is

IF.

When

the Wide

is

made

The audio signal from the Audio Filters and Gain Control

Peak Detector, the Audio Average Detector or the Audio RMS detector. The Audio Average and RMS Detectors are used primarily for measuring noise. The output from the detectors is routed into the Voltage-to-Time Converter.

The Voltage-to-Time Converter within the voltmeter converts the dc input into a time interyal. During

is

the interval, the 10 MHz Time Base Reference represents the dc voltage. Other inputs an audio level detector and the AM calibrator.

The Distortion Analyzer measures the distortion of either the internal demodulated signal or an audio

to

signal applied externally

of

the input signal must be either 1 kHz or

measuring the amplitude of the signal before and after a notch filter that

two

ac signals are converted

Distortion

(The Audio RMS Detector can also be used or the ac level of an external audio signal applied to the MODULATION OUTPUT/AUDIO INPUT connector.)

is

computed

the MODULATION OUTPUT/AUDIO INPUT connector. The frequency

to

dc by a the Audio RMS Detector and then measured by the voltmeter.

as

the ratio of the voltage out of the notch filter

to

the voltmeter, which are not shown, include outputs from

counted by the Counter, and the resultant count

400

Hz. The distortion on the signal

to

measure the demodulated AM, FM,

is

converted

to

a dc voltage by the Audio

is

determined by

is

set

to

1

kHz

or

400

to

the voltage into the filter.

or

OM internally

Hz.

The

1-11

General Information Model 8901B

The frequency of the audio signal at the MODULATION OUTPUT/AUDIO INPUT connector,

or

whether internal the input signal function is during the count is read by the Controller which computes and displays the signal frequency.

The AM and FM Calibrators provide a nominal 10.1 MHz signal with a precisely known amount of

or

AM

or

via the Sensor Module), the modulation is measured and the calibration factor of the AM Demodulator demodulation of the calibrator signal.

also

FM. When this

external,

is

used

used by the Voltage-to-Time Converter.) The number of time base pulses received

is

computed and displayed. Related front-panel functions are automatically set for proper

is

measured by a reciprocal-type Audio Counter. In the Audio Counter,

to

gate the 10 MHz Time Base Reference into the main Counter. (This gating

signal

is

applied

to

the instrument’s RF INPUT connector (either directly

or

FM

P

(a)

BASEBAND SIGNAL

1.5 1

.o

0.5

0

Figure

1-1

1.

MODULATION

The Modulation Analyzer can demodulate and measure three types of modulation: amplitude modulation (AM), frequency modulation (FM), and phase modulation (@M). In general, modulation is

that

characteristic of a signal which conveys the information. A signal without modulation

continuous-wave (CW)

frequency. These conveyed

or

both of these parameters

The RF signal which baseband signal and can be of any arbitrary form (for example, voice, tone, noise). Demodulation the process of recovering the baseband signal from the modulated carrier. The Modulation Analyzer

can measure the modulation on carriers in the range of

is specified present

by

at

the MODULATION OUTPUT connector.

Amplitude Modulation

1-3.

BASICS

two

them

for

modulation

(b)

AMPLITUDE MODULATED CARRIER

I

A Baseband Signal and the Corresponding Amplitude Modulated Carrier

is

said to be

signal.

parameters, however, are static (time invariant). Consequently, the information

is

scant-you know only that a signal

is

CW signals contain

is

altered as a function of time, the signal

modulated is called the carrier. The modulating signal

rates

generally between

two

information-carrying parameters: amplitude and

is

present at a certain frequency. When one

is

said

to

150

kHz to 1300 MHz. Measurement accuracy

20

Hz

and

100

kHz.

The demodulated signal

be modulated.

is

referred to

as

a

the

is

1-12

As

the name implies, a carrier is amplitude modulated when its amplitude

time. Figure 1-3 shows a carrier with amplitude modulation and, for reference, also shows the baseband

As

signal.

This trace

minimum called the trough. A quantity which describes the amount of AM

you can see, the tips of the carrier trace out a waveform that resembles the baseband signal.

is

called the envelope. The envelope rises to a maximum called the peak and drops

is

varied

or

the AM depth

as

a function of

is

to

the

a

Model

8901B

General Information

modulation index. If the peak amplitude is called P and the trough amplitude is called

index

rn

(usually expressed in

In the example

of

Figure 1-4 shows

Figure

AM

signals with modulation indexes varying from 0 to

1-3,

%)

is

P

=

m=

defined

m=-

1.5

and T =

1.5

-

1.5

+

as

P-T

+

0.5

x

0.5

(a)

x

100%.

0.5;

100%

0%

AM

therefore,

=

50%.

(CW)

100%.

T,

the modulation

(b)

(c)

(d)

30%

70%

100%

AM

Figure

1-4.

AM

for

Various

Depths

1-13

General Information Model 8901B

When the baseband average carrier level, and the expression for modulation index becomes

This

is

the expression which the Modulation Analyzer evaluates when making an AM measurement,

Referring back

The Modulation Analyzer makes an AM measurement known, fixed level by means of and the amplitude of the recovered baseband the detector

is

signal

A,

and the envelope peak,

A+r-A+r

m=

A+r+A-r

to

Figure 1-3, it

r,

which

is

symmetrical, the modulation index can

T,

relative

x

=

-

2A

100%

signal

27

A

=

x

=

is

100%

1

50%

x

100%

is

apparent that

m

=

-

0.5

1

an

automatic level control (ALC) circuit. The signal

(in

effect) multiplied by the constant

also

be expressed

to

the carrier. Then

r

=

-

x

100%.

A

and

T

=

0.5

so,

by

forcing the average carrier level,

measured with a peak detector. The output of

1OO/A

P

=

as

before

and displayed

in

terms of the

A+r,

and

T

=

A,

is

then demodulated,

as

the

9%

AM.

A-

to

r,

a

I

r

(a)

BASEBAND SIGNAL

(b)

I

Figure

The range

100%.

An example of such is suppressed-carrier AM. The Modulation Analyzer such signals. Nevertheless, there are cases, when the Modulation Analyzer will display a modulation index that exceeds peak

of

modulation indexes

There are, however, types of modulation that produce modulation indexes greater than 100%.

100%.

is

greater than the average carrier level. This is illustrated in Figure 1-6.

This can occur,

AMPLITUDE MODULATED CARRIER

1-5.

AM with an Asymmetrical Baseband Signal

for

AM measurements by the Modulation Analyzer

for

example, on an asymmetrical waveform where a narrow

is

essentially 0 to

is

not intended for measuring

1-14

Model 8901B General Information

Figure

I

1-6.

AM with Modulation Exceeding

100%

as

Measured

I

by

the PEAK+ Detector

Exponential Modulation

Exponential (or angular) modulation

is

or phase of the carrier

is

impossible

analyzing the received signal unless specific information about the baseband

It

is

certainly true a frequency modulator. when the varactor bias

is

generated by a phase modulator. A varactor diode across an varactor driven from a well-buffered carrier source. This modulator simultaneously produces

The signal from both modulators will show readings on the Modulation Analyzer when in both the

FM

and

deviation, which measuring

the average carrier phase. Phase and frequency have the relationship

frequency or frequency

QM

by integrating the demodulated FM.

This relationship signal shown an

FM,

assumed

The frequency goes up on the positive peak of the baseband signal and down on the negative peak. The phase modulated signal, however, a discontinuity where the baseband signal switches amplitude. The waveform of the figure was contrived

so

that

will occur when the baseband signal switches amplitude, but the phase shift does not need

is

the constant zero except for a positive spike (impulse) where the baseband signal switches positive

and

a

negative spike where the square wave switches negative.

Now look the baseband signal slopes upward and a continually decreasing frequency The phase modulator produces a signal that resembles the signal from the frequency modulator for the square wave baseband signal. This

is

slope upward. When the slope is negative, the phase shift frequency shift. For the triangle wave baseband signal, the shift in frequency when the slope changes is proportional

to

tell

bias

is

varied.

QM measurement modes. When

is

QM,

the peak phase deviation

is

a

square wave. The three waveforms under

QM, and

that the phase modulator doesn't produce AM-only

a

180"

at

positive, the phase shift

AM

phase shift occurred exactly at a zero crossing of the carrier. In general, a discontinuity

to

occur at a zero crossing of the carrier. Mathematically, the derivative of a square wave

the triangle wave. The frequency modulator produces a continually increasing frequency

to

the change in slope.

varied. Frequency and phase modulation are very closely related. In fact,

whether the signal was produced by a frequency modulator or phase modulator by

to

say that a signal

A

varactor diode across the tank circuit of an

is

varied. It

(It

is

assumed

the maximum frequency excursion from the average carrier frequency. When

is

the derivative of the phase. In fact, the Modulation Analyzer demodulates

most easily visualized by some examples. Look at Figure 1-7. The

modulator respectively. (The

is

the generic name given

is

frequency modulated when the modulation

is

also true

that

the carrier

a

signal

is

on the slope of the filter and

to

modulation in which the frequency

signal

is

given.

is

generated by

LC

oscillator

is

phase modulated when the modulation

RF

filter

will

produce

produce QM when the

that

the

AM.)

in

FM, the quantity being measured

is

measured, which

is

the maximum phase excursion from

that

phase

is

the peak frequency

is

the integral of the

first

it

are the result of applying this signal

AM

waveform

is

peculiar. The frequency

is

because the derivative of a constant slope

is

continually increasing, thus producing a uniform frequency shift

is

continually decreasing and produces a downward

is

included only for reference.)

QM.

The

FM

waveform

generally constant throughout except for

is

not necessarily 180" and

as

the signal slopes downward.

is

a

is

as

constant. When the

it

FM

filter

is

baseband

to

It

is

expected.

as

1-15

General Information Model

uu

BASEBAND SIGNAL

8901B

SIGNAL FROM FREQUENCY M

SIGNAL FROM PHASE MODULATOR

SIGNAL FROM AMPLITUDE MODULATOR

(a)

SQUARE WAVE BASEBAND SIGNAL

Now

note

the sine wave the same except for the frequency is highest when the baseband signal

phase modulated signal, the frequency

a positive direction. This occurs

is

when the slope

most negative.

0 D U LATO

of

Figure 1-7(c). The signals from the frequency and phase modulators

90'

phase shift between the

R

is

highest when the slope of the baseband signal

at

the positive-going zero crossing. Similarly, the frequency

SIGNAL F

SIGNAL FROM AMPLITUDE MODULATOR

(b)

Figure

is

most positive and lowest when most negative.

two.

1-7.

For

RO

M F REQU ENCY MO DU LATO

SIGNAL FROM PHASE MOOULATOR

TRIANGLE WAVE BASEBAND SIGNAL

Signals from

the frequency modulated signal, the

Requency,

Phase,

is

steepest

R

For

is

lowest

and

look

the

in

1-16

If

in the last example, the rate, but not the amplitude, and lowest frequencies often. However, for the signal from the phase modulator, not only do the frequency peaks occur more often, but the excursions are large because the slopes crossings. See Figure 1-7(d).

The

maximum

400

rad

or

baseband waveform will result in different readings in

frequency deviation which can be measured

400

kHz divided by the modulation rate, whichever is smaller.

of

the signal from the frequency modulator stay the same-they just occur more

of

the baseband signal

of

the baseband signal are steeper

is

400

kHz. The maximum phase deviation is

PEAK+

than

PEAK-.

As

is

increased, the highest

with

AM,

at

the zero

an asymmetrical

Model

8901B

General Information

BASEBAND SIGNAL

SIGNAL FROM FREQUENCY MODULATOR

SIGNAL FROM PHASE MODULATOR

W

BASEBAND SIGNAL

SIGNAL FROM FREQUENCY MODULATOR

SIGNAL FROM PHASE MODULATOR

W

SIGNAL FROM AMPLITUDE MODULATOR

(c)

SINE WAVE BASEBAND SIGNAL

~~

SIGNAL FROM AMPLITUDE MODULATOR

(d)

SINE WAVE BASEBAND SIGNAL:

3/2

THE RATE OF

Amplitude Modulators for Various Baseband Signals

Other Considerations

In practice, of AM-called incidental AM or AM-on-FM. Likewise, an AM signal usually contains amount of incidental FM and cPM. In order Modulation Analyzer itself must not contribute to and FM rejection.

A

typical CW signal also contains a

modulation

FM specifications quantify the residual modulation internal

Residual modulation affects the modulation readings in a manner which depends on the detector used, the nature

the peak detector

ratio. This

3.

When the average detector square root insignificant, however, when the signal-to-noise ratio rises above a few

by filtering the demodulated signal.

it

is

difficult

is

generated by such things as line hum, noise, and microphonics. The residual AM and

of

the residuals, and the signal-to-noise ratio.

is

discussed under

of

the sum

to

produce an FM or cPM

to

accurately measure this incidental modulation, the

small

amount of residual AM, FM, and ckM. The residual

used, the residuals add in a way

Residual Noise Effects

is

used, the residuals add approximately in an

of

the squares

of

the noise and the signal. The effect

signal

it.

in the

which does not also have a small amount

This contribution is specified

to

the Modulation Analyzer.

If

that

the residual

is

statistically related

is

predominately noise, when

Detailed Operating Instructions

rms

dB.

Noise can be further reduced

as

AM rejection

to

the signal-to-noise

manner, that

of

this noise becomes

a

small

in Section

is,

the

(c)

1-17

General Information Model 8901B

In FM broadcasting and communications, the signal-to-noise ratio is improved

a

signal boost

75

the demodulated FM can be de-emphasized the display.

high-frequency boost before applying

is

a simple

ps

(which corresponds to

6

dB

per octave with the

a

3

dB

comer of

it

to

the modulator. This

3

dB

comer specified by a time constank

2.12

kHz) for commercial broadcast

to

equalize the signal at the modulation output and

is

called pre-emphasis. The

by

giving the baseband

for

example,

FM.

If

desired,

at

1-18

Model

8901B

General

Information

RF

Table

Power

1-1.

Specifications

The HP 8901B Modulation Analyzer, with HP 11722A Sensor Module, performs RF Power Measurements from

-20 dBm

100

kHz to

(10

pW)

to

+30 dBm (1W) at frequencies from

2.6

GHz. The 8901B can be used with any of the HP 8480 series power sensors (8481A/lB/lH/2A/ 2B/2H/3A/4A/5A) to make power measurements from

-70 dBm

100

(10

pW) to +44 dBm (25W) at frequencies from

kHz

to 26.5 GHz. The 8480 series sensors also work with the HP 435A and HP 436A Power Meters. Unless otherwise specified, the specifications shown below refer to the 8901B only. A detailed explanation of how the uncertainty specifications provided below affect the absolute power measurement accuracy of the vided in Application Note

64-1.

8901B

is pro-

RF POWER RESOLUTION':

0.1%

of full scale in watts

0.01

dB in dBm

LINEARITY

RF range linearity

or

dBTelative mode.

(includes sensor non-linearity):

2

RF RANGE LINEARITY

or

volts mode.

RF range-to-range change error.

(using Recorder Outputfi

20.02 dB, RF ranges 2-5.

20.03 dB, RF range

Using front-panel display add

1.

21

count of

least-significant digit.

RF RANGE-TO-RANGE CHANGE ERROR:

20.02 dB/RF Range Change from reference range.

INPUT SWR: ZERO SET (DIGITAL SETTABILITP

c1.15, using 11722A Sensor Module.

OF

ZERO):

50.07% of full scale of lowest range.

Decrease by a factor of

Supplemental Characteristics:

__

ZERO

DRIFT OF METER:

20.03%

of

full scale/"C of lowest range.

10

for each higher range.

NOISE (at constant temperature, peak change over any one-minute interval for the Module and

0.4%

0.13%

0.013%

0.0013%

0.00013%

8481AIlBIlH/2A/2B/2H/3A/SA

of full scale

of

full scale

of

full scale

of

ojfull scale

full

on

range 1 (lowest range).

on

range

on

range

scale

on

For HP 8484A Sensor multiply noise

2.

range

11

722A Sensor

3.

4.

5.

by

Sensors):

five

on

all

ranges.

The

8901B

internal processing is done

When using specification and became the predominont error. \\'hen operating top AF power range. add the Power Sensor Linearity percentages

the power sensor specifications.

fundamental RF Power measurement units are watts. Further

8484A

on

this number

sensor the noise specification may mask the linearity

to

displa!, all other units.

on

found

the

in

(1

of

6)

ZERO DRIFT OF SENSORS

(1

HOUR,

AT CONSTANT

TEMPERATURE AFTER 24-HOUR WARM-UP):

20.1%

offull scale of lowest range

Module and

848

IA/lB/l H/ZA/ZB/ZH/3A/SA

for

11722A Sensor

sensors.

22.0%

of full scale

Decrease

RF

'OWE'

by

RANGES

ANALYZER WITH

-20

dBm to

-10

dBm to

$0

dBm

to

+10

+IO

dBm to

f20

dBm

to

RESPONSE TIME

<IO

seconds, range

<I

second, range

<100

milliseconds, ranges

a

factor

-10

+O

$20

$30

of

lowest range

of

10

for

OF

8901B

11

7224 SENSOR MODULE:

dBm

(10

pW

dBm

(100

pW

dBm

(1

mW

dBm

(10

mW

dBm

(100

mW to

(0

to

99%

OF READING):

1.

2.

3-5.

for

each higher range. MoDULATzoN

to

100

to

1

mW),

to

10

mW), range

to

100

lW),

8484A sensor.

pW),

range

2.

3.

mW), range

range

5.

1.

4.

DISPLAYED UNITS:

volts,

mV,

pV,

dB

watts, dBm, dB

mV,

dB

dBreiotive,

%re

pV.

,,,,,

V.

INTERNAL NON-VOLATILE CAL-FACTOR TABLES

(user-modifiable using special functions):

MAXIMUM NUMBER OF CAL FACTORIFREQUENCY ENTRIES:

Table

#1

(Primary):

16

pairs plus Reference

CaI

Factor.

Table #2 (Frequency Offset):

22

pairs plus

Reference

CaJ

Factor.

MAXIMUM ALLOWED FREQUENCY ENTRY:

200

GHz.

50

FREQUENCY ENTRY RESOLUTION: CAL FACTOR RANGE:

40

to

120%.

CAL FACTOR RESOLUTION:

Power

POWER

1.00

Reference

OUTPUT:

mW.

Factory set to

20.7%

0.1

%.

traceable to the

kHz.

U.S.

National Bureau of Standards.

ACCURACY:

year

~ ~~ ~~~

21.2% worst case (20.9%

[OOC

to

55OC).

rss)

for one

Supplemental Characteristics:

FREQUENCY:

SWR:

1.05

FRONT PANEL CONNECTOR:

50

iMHz

nominal.

Type-i\l

female.

All parameters describe performance in automatic operation or properly set manual conditions. Specifications describe the instrument's warranted performance. Supplemental Characteristics (shown in italics) are intended to provide information useful in applying the instrument by giving typical, but non-warranted, performance parameters.

1-19

General

Information

Amplitude Modulation

RATES:

20

Hz to

10

kHz,

150

kHz

Sf,<

20

Hz to

100

kHz,

10

MHz

5fcl

DEPTH: ACCURACY3*

I I

I

*0.3%

to

99%.

4*

5:

AM

Accuracy

‘2%

Of

reading

21

digit

23%

of

reading

21

digit

”%

Of

reading

21

digit

+’%

Of

reading

21

digit

Flatness Frequency Range Rates

of

reading

21

digit

Frequency Range Rates Depths

150 kHz-10 MHz 50 Hz-10 kHz

150 kHz-10 MHz

I I

10 MHz-1300 MHz I 50 Hz-50 kHz I 5%-99%

I

10 MHz-1300 MHz I 20 Hz-100 kHz

MHz-1300

I

MHz

Table

10

MHz.

1300 MHz.

20 Hz-10 kHz

90

Hz-10 kHz

1-1.

Specifications

5%-99%

I

to

99%

I

to

99%

Depths

20%-80%

(2

of

6)

FM Accuracy Frequency Range Rates

I

22’”,10f~$lng

I

+’%

I I

Of

+l

pr5Xadlng

21

For

I

250 kHz-10 MHz

reading

dlglt

rms detector add 23%

10 MHz-1300 MHz

I

10 MHz-1300 MHz

I 1

50 Hz-100 kHz I 5400

I

20

of

DEMODULATED OUTPUT DISTORTION8,

I

THD

<0.1% <0.1%

I

Frequency Range

I

400

kHz-10 MHz

10

MHz-1300 MHz

I

20

Model

Deviations

20

Hz-10 kHz I 540

Hz-200 kHz

reading.

Rates

20 Hz-10 kHz

Hz-100 kHZ <lo0 kHZ

I

5400

9:

I

Deviations

I

<lo

8901B

kHzpeak

kHZpeak

kHz

I I

I

DEMODULATED OUTPUT DISTORTION:

<0.3% THD

<O.S%

FM

REJECTION

RESIDUAL AM

Supplemental Characteristics:

DETECTORS:

average

MAXIMUM DEPTH, RESOLUTION, AND MAXIMUM DEMODULATED OUTPUT SENSITIVITY ACROSS

AN OPEN CIRCUIT

Maximum

Resolution

0.1%

0.01%

0.001

1

(rms detector

But not

detector.

generated by the Analyzer. accuracy by

6

input signal.

’

tic impedonce.

to

Peak residuals must be accounted for in peak readings.

For peak measurements only:

Flatness is the variation in indicated

For optimum flatness. cables should be terminated trith their choracteris-

for

550%

depth.

THD for

[rms

%

exceed:

0.1%

595%

depth.

(50

Hz TO 3 kHz BW)4:

(50

HZ

to

3

kHz BW):

+peak, -peak, kpeak/2, peak hold,

sinewave calibrated), rms.

(600Q

OUTPUT IMPEDANCE)’:

Maximum

Demodulated Output

Sensitivity

0.01

V/percent

0.1

V/percent

I

0.1

only)

50

Hz to

of reading for each

V/percent

40

kHz rates for stoted accuracy with rms

AM

accuracy may be affected b!. distortion

In

the worst case this distortion can decrease

0.1%

of

distortion.

AM

depth for constant depth

<O.Ol%,,,.

Depths

I

AMpeak?40.

AMpeak<40.0%

AMrms<3.0%

0%

1-20

on

AM

Rejection Frequency Range Rates

<20

HZ

peak

deviation

RESIDUAL FM

<8

Hz,,, at

frequency

Supplemental Characteristics:

MAXIMUM FM DEVIATION, RESOLUTION, AND MAXIMUM DEMODULATED OUTPUT SENSITIVITY ACROSS AN OPEN CIRCUIT IMPEDANCEI7:

Maximum

Resolution

100

10

1

I

0.1

(rms detector

Resolution is increased one digit with

de-emphasis and pre-display on. The demodulated output signal present at the

Modulation Out/Audio In connector is increased in

ampliiude

But

not

1Vith

to exceed:

750

de-emphasis filter.

for modulation outputs

mum deviation for a measurement ronge. at rates

150 kHz-1300 MHz

(50

Hz

to

1300

MHz, decreasing linearly with

to

<I

Hz,,,

Maximum

Demodulated Output Deviations

Sensitivity

I

Hz

HZ

Hz

FS

de-emphasis and pre-display

only)

by

a factor

20

I

0.01

0.1

1.0

kHz rates and

>4V

peak. This condition can occur near maxi-

~ ~~

3

kHz BW):

for

100

mV/Hz

mV/Hz mV/Hz

mV/Hz

of

10

with

40

400

Hz

or

1 kHz

MHz and below.

(600Q

OUTPUT

I

aF,,,r40

4.0

dF,,,,c40

AF,,,<4

4(ms<0.3

750

ps

de-emphasis.

kHz peak deviations with

“off.”

distortion is

<2

kHz.

ps

AM

kHz

not

Depths

550%

(4

F)

kHz

I

kHz

750

specified

j~s

Model

-

DETECTORS:

STEREO SEPARATION

8901B

THD

4.3%

average

Frequency Range

150

kHZ-400 kHZ

Rates Deviations

20

HZ-10 kHZ 40 kHz

+peak, -peak, -.peak/2, peak hold,

(rms

sinewave calibrated],

(50

Hz

to

25

rms.

kHz):

lbble

>47

1-1.

dB.

Phase Modulation

RATES:

200

Hz

to

10

kHz,

150

kHzlfc<

200

Hz

to

20

kHz,

10

MHzlf,l

ACCURACY4:

24%

of reading

+3%

of

reading

For

rms

detector add

DEMODULATED OUTPUT DISTORTION:

AM

REJECTION

<0.03

radians peak

MAXIMUM DEVIATION, RESOLUTION, AND MAXIMUM DEMODULATED OUTPUT SENSITIVITY ACROSS AN OPEN CIRCUIT IMPEDANCE)':

400

-

200

u)

:

100

.-

n

Output

(FOR

0.1

Radian

Resolution

0.01

VARaBRaqin

21

nravlh,

digit, digit,

23%

50%

(50

Hz

150

kHzlf,<

10

MHzlfcS

of

reading.

AM AT

to

3

kHz

(600Q

150 kHzSf,<lO

10

MHz.

1300

MHz.

I

kHz

BW).

OUTPUT

10

MHz.

1300

MHz.

<O.l%

RATESY:

MHz

THD.

Specifications

Supplemental Characteristics:

~~

(3

of

6)

CARRIER FREQUENCY: MODULATION RATE: OUTPUT LEVEL:

Frequency Counter

RANGE MAXIMUM

ACCURACY:

Supplemental Characteristics:

MODES:

SENSITIVITY

150

kHz

RESOLUTION:

f

reference accuracy

digit, fc

f

reference accuracy

digit or

Frequency and Frequency

between the frequency entered via the keyboard and the actual

RF

input frequency).

IN

0.22

mVrmP

(-60

be entered from keyboard.)

Internal Reference

FREQUENCY AGING RATE:

<1

x

<1

x

Supplemental Characteristics:

10

10-6/month. 10-g/day (Option

10.1

10

-25

dBm.

to

1300

MHz.

f3

<lo0

MHz.

f3

30

Hz,

whichever

MANUAL

General

MHz.

kHz.

1

Hz.'O

counts of least-significant

is

larger,

Error

[displays the difference

TUNING MODE:

Information

fc

2

100

MHz.

dBm). [Approximate frequency must

MHz

002).11

.1

P

100

200

7

rrns

detector

O.OOO1

Resolution

400

Radian

only

lk 2k 4k

Modulation

Rate

Supplemental Characteristics:

MODULATION RATES:

usable

from

20

Hz

nith degraded performance.

DETECTORS:

average

+peak. -peak. +peak/2. peak

(rrns

sinewave calibrated).

rrns.

Modulation Reference

AM CALIBRATOR DEPTH AND ACCURACY:

33.33%

accuracy

FM

34

an accuracy

rev.

depth nominal, internally calibrated to an

of

+0.1O/0.

CALIBRATOR DEVIATION AND ACCURACY:

kHzpeak

deviation nominal, internally calibrated to

of

-.0.1%.

19DEC88

(Hz)

to

hold.

10k

100

kHz

201

Agmg Rate

Lme Voltage Effects

(4%.

-10%

Change)

Short Term Stability

lo

10

Hz

for

(To

that

"After

instmments

display

the

contains

this

30-day warmup.

Standard

<1 x 10

Line Voltage

<1

x

-6/mo.

10

-

with

firmware date code, select 42.0

capability, contact the nearest

firmware date codes 234.1985 and below.

-6

SPCL.)

To

HP

sales office.

Option

<1

x

10

<6

X

<I

x

10

1 s average

order a

ROM

002

-9/day

10

-lo

-9

for

set

1-21

General Information Model

Table

1-1.

Specifications

(4

of

6)

8901B

Audio Frequency Counter

FREQUENCY RANGE:

20

Hz

to 250

kHz.

(Usable to

600

kHz.1 MAXIMUM EXTERNAL INPUT VOLTAGE: Accuracy (For Demodulated Signal~l:'~

I

23

(3

Accuracy (For External Signals):11

~

+3

Accuracy

counts of least-significant digit

+Internal Reference Accuracy

20.02

Hz

t

Internal Reference Accuracy

-0.2

HZ

2

Internal Reference Accuracy

kHz

low-pass filter inserted)

Accuracy

counts of least-significant digit

+Internal Reference

20.02

Hz

z

Internal Reference Accuracy

I

Frequency I Modulation (Peak)

>1

kHz

@M

dl

kHz

@M

1.5%

53

kHz

0

Frequency Level

>1

kHz 2100

51

kHz

Supplemental Characteristics:

DISPLAYED RESOLUTION: 6 digits.

MEASUREMENT RATE:

2

reading+.

COUNTING TECHNIQUE:

Reciprocal with internal

AUDIO INPUT IMPEDANCE:

10

MHz

100

time

kR

nominal.

base.

Audio Distortion

FUNDAMENTAL FREQUENCIES:

400

Hz

2

5%

and

1

kHz

25%.

MAXIMUM EXTERNAL INPUT VOLTAGE: DISPLAY RANGE:

0.01%

to

IOO.Ooio

DISPLAYED RESOLUTION: ACCURACY: SENSITIVITY:

Modulation:

External:

RESIDUAL NOISE AND DIST0RTIONI3:

0.3'0

(-50

Supplemental Characteristics: MEASUREMENT 3 dB BANDWIDTH:

DETECTION: MEASUREMENT RATE:

AUDIO INPC'T IMPEDA'VCE:

(-80.00

2

1

dB of reading.

0.15

kHz

0.6

radian peak

100

myrms.

dB).

temperature

True

rrns.

dB

to

0.01%

peak

FLI.

&XI.

<4O0C.

I

rradinp/s.

100

0.00

or

1.5%

k!!

dB).

0.01

peak

20

nominal.

3Vrms.

AM

210%

FM

21.0 kHz

2

1.5

AM

210%

FM

2

1.0 kHz

21.5

d

AM

0

15 kHz

<

1.0

15

radian d @M

<

1

5

radians

mV,,,

rlOO

mVrms

3V.

dB.

AM

Hz

to

radians

<

10%

5

FM

kHz

or

50

kHz.

Audio

FREQUENCY RANGE: VOLTAGE RANGE: ACCURACY:

Supplemental Characteristics:

I

RMS

2

4.0%

Level

50

100 mV

of

reading.

Hz

to

40

3V.

kHz.

FULL RANGE DISPLAY: .3000V, 4.000v. AC CONVERTER: true-rms responding for signals with

crest factor of MEASUREMENT RATE: AUDIO INPUT IMPEDANCE:

13.

2

reading+.

100

kR

nominal.

Audio Filters

DE-EMPHASIS FILTERS:

750

ps.

De-emphasis filters are single-pole, low-pass

filters with

3183

750

gs.

50

HZ HIGH-PASS FILTER

Flatness:

300

HZ HIGH-PASS FILTER

Flatness:

3

kHz LOW-PASS FILTER

Flatness:

15

kHz LOW-PASS FILTER

Flatness:

>20

kHz LOW-PASS FILTER

Flatness:

Supplemental Characteristics:

3

Hz

for

50

<I% at rates?

<I%

~~

dB frequencies

ps.

at rates? 200

at rates

DE-EMPHASIS FILTER TIME CONSTANT ACCURACY:

23%.

HIGH PASS AND LOW FREQUENCY ACCURACY:

>20

kHz LOW PASS FILTER:

3

dB

Cutoff

Frequency:

OVERSHOOT ON SQUARE WAVE MODULATION":

<IO/b.

12

I\'ith

the

loi~.pass

readings.

13

For

dernodulol~d

must

br

uccounled

o.\l

j

14

The

>?O

squurwoix=

and

signals.

for

in

iHz

lon.pass filter

nodulotion

25

2122

11

510

110

PASS

high-puss

the

residuol

distortion

is

ps,

50

ps,

of

6366

Hz

for

75

gs.

(2

POLE):

Hz.

(2

POLE]:

1

kHz.

(5

POLE):

kHz.

(5

POLE):

kHz.

(9

POLE BESSEL)I4:

kHz.

FILTER

23%.

100

kHz

nominal.

audio

fillers used

noise

measuremrnts

intended

generaled

for

minimum

75

ps,

Hz

and 212

3

dB

lo

stabilize

ii.e

residual

and

for 25

Hz

frequency

b!.

the

A.M.

overshoot

ps,

for

8901B

F.M

with

or

1-22

Model

8901B

lbble

1-1.

Specijications

(5

of

6)

General Information

RF Input

FREQUENCY RANGE: OPERATING LEVEL:

Minimum

I

12

I

Operating

mVrms

level

(-25

dBm)

Supplemental Characteristics:

TUNING:

Normal Mode:

Track Mode:

Acquisition Time (automatic operation):

-I

.5

seconds.

INPUT IMPEDANCE: MAXIMUM SAFE DC INPUT LEVEL:

150

kHz to

Maximum

I

Operating

'lms

Source

I

Automatic and manual frequency entry.

Automatic and manual frequency entry,

f,

210

MHz.

50R

nominal.

level

("peak)

SWR

1300

e4

General Specifications

TEMPERATURE:

REMOTE OPERATION:

line switch are remotely controllable.

HP-IB COMPATIBILITY

SHI, AHI,

CO,

El.

EMI:

Conducted and radiated interference requirements publication

POWER:

WEIGHT: DIMENSIONS:

HP SYSTEM I1 MODULE SIZE:

100.120,

200

VA maximum.

Net

(7.5"

X

16.8"

Operating: Storage:

T5,

TEO.

of

11.

220.

23.4

kg.

190

X

21.7").

L3,

VDE

or

(51.5

mm.

O°C

-55%

HP-IB;

alI

(defined in

LEO.

SRI,

0871

(Level

240V

(+5%.

lb.);

Shipping 31.1 kg

H

X

426

mm.

177.0

to

55OC.

to

75OC.

functions except the

IEEE

RLI.

B).

-lO0/o):

M'

H

MHz.

Frequency

I I

150

5V.

488-1978):

PPO.

is

and

X

551

X

1

MLY

Range

kHz-650 MHz

DC1.

DT1,

within the

CISPR

48-66

Hz:

(68.5

lb).

mm.

D

X

497.8

D.

HP

8901

B

Rear Panel Inputs/Outputs

Supplemental Characteristics:

FM OUTPUT:

circuit: -6V/MHz, dc coupled, 16 kHz bandwidth (one

pole).

AM OUTPUT:

circuit,

pole).

RECORDER OUTPUT:

measured results, resolution range into an open circuit.

IF

OUTPUT:

-27 dBm to

10

MHz REFERENCE OUTPUT:

levels with Option

10

MHz

0.5Vpeak.lo.peak

LO

INPUT (Option

1301.5

RF SWITCH REMOTE CONTROL OUTPUT:

output signals necessary to remotely control either an HP

3331

FREQUENCY OFFSET MODE REMOTE CONTROL

OUTPUT:

(Special Function

frequency

'5~xternai reference

10

kR

impedance,

10

kR impedance,

-8

mV/%, dc coupled, 16 kHz bandwidth (one

DC

1

kR

impedance,

50R

impedance,

-3

dBm.

(OV

to

>2.2V

into an open circuit). Available only

002

Ixlo-g/day internal reference.

REFERENCE INPUT15

minimum input level.

003):

5OR

MHz, 0 dBm nominal.

1B/C Option

TTL

high output if in frequency offset mode

>O,

01

27.1

TTL

low output for

accuracy

or

affects

-9V

to 6V into an open

-4V

to

OV

into an open

voltage proportional to the

OV

to 4VfOr each

150

kHz

to

2.5

50R

impedance,

>500R

impedance,

1

or

an HP 8761A RF switch.

27.3)

with an external

accuracy

-1.27

all

other cases.

ut

ail

iiie~asurements.

MHz,

TTL

MHz

Provides

LO

,

to

1-23

General Information

Table

1-1.

Specifications

(6

of

Model

6)

8901B

Carrier Noise

FREQUENCY RANGE: CARRIER POWER RANGE:

12.5

kHz,

+30

dBm to

DYNAMIC RANGE: CARRIER REJECI'ION (temp. 135'C)

at least

1

channel spacing

(Options

10

MHz to

25

kHz and

-10

dBm; carrier noise filter.

115

dB.

1300

+30

dBm to

30

kHz filters.

or

5

kHz, whichever

030-037)

MHz.

-20

>90

dB; for offsets of

RELATIVE MEASUREMENT ACCURACY:

levels

2-95

dBc;

12.5

kHz,

25

kHz and

50.5

dB; levels

1-129

dBc/Hz; carrier noise filter.

CARRIER NOISE FILTER:

Filter Noise Bandwidth:

0

-10

-20

-30

E

0

-40

C

.-

5

-50

m

'3

a-w

-70

-80

-90

-6

-4 -2 0 2 4

2.5

kHz nominal.

12.5

kHz Filter Shape

6

8

10 12 14 16 18 20

Relative Frequency

(kHz)

dBm;

is

greater.

5

0.5

dB;

30

kHz filters.

Noise Bandwidth Correction Accuracy (stored in

non-volatile memory):

Supplemental

Characteristics:

20.2

dB.

ADJACENTIALTERNATE CHANNEL FILTERS:

6

dB Filter Bandwidth:

8.5

kHz,

12.5

kHz adjacent-channel filter.

16.0

kHz,

25

kHz adjacent-channel filter.

30.0

kHz,

30

kHz (cellular radio) alternate-

channel filter.

TYPICAL NOISE FLOOR:

power level.

For

System noise performance add

-150

dBc/Hz, 0 dBm carrier

contribution.

25

kHz Filter Shape

CEPT

Specification

6

8

10 12 14 16 1820222426

(kHz)

-

k

0

._

0

.-

a

0

-10

-20

-30

40

-50

-60

-70

-80

-90

-6

and

-4 -2 0 2 4

Relative Frequency

LO

1-24

30.0

kHz Filter Shape

-12 -8 -4 0 4 8 12

Relative Frequency

16

20 24 28 32

(kHz)

Carrier Noise Filter Shape

0

-10

-20

-30

-

!i

-40

C

0

i5

-50

%

a

-60

-70

-80

-90

36

40

-2-1

Relative Frequency

0

f

2

3

4

5

6

(kHz)

Model 8901B

General Information

Instrument

Type

AM/FM Test

Source

Table

~~ ~~~~ ~ ~

Carrier Frequency: within range Output Level: FM Deviation: 400 kHz peak maximum FM Distortion:

<

-72

dB at

rate

<

-72

dB at 400 MHz carrier and

rate

FM Flatness:

10.1% k0.2570

CW Residual FM:

incidental AM:

AM Depth: AM Distortion:

AM Flatness:

iO.1%

f0.25%

incidental QM:

Residual AM: AM Linearity:

fO.l

3~0.2% at

from 20 Hz to

to

200

560 MHz

and 1 kHz rate in a

5%

<

-66

dB at

<

-60 dB at

from

kHz rate in a

YO

at

<95%

49%

1-2.

Recommended Test Equipment

Critical Specifications

>

-20

dBm

12.5

MHz carrier with

100

kHz rates

<3

Hz rms in a

<0.08%

to

-30%

45%

50

20

<0.008

50

<0.01%

AM at

50

Hz to 3 kHz bandwidth

99%

AM at 20 Hz to AM at

Hz to 50 kHz

Hz

to

100

kHz

rad peak at 12.5 MHz with

Hz to 3 kHz bandwidth

rms in a 50 Hz to 3 kHz bandwidth

AM AM

100

20

10

to

400

50

MHz with

Hz to

(1

1300

MHz

12.5

kHz deviation and 40 kH

kHz deviation at

Hz to 3 kHz bandwidth at

40

kHz peak deviatioi

100

kHz rates

100

kHz rates

50%

400

AM at a

of

kHz

1

4)

Suggested

Model

HP

11715A

Attenuator,

3

dB

(2

required)

Attenuator,

6

d0

Audio

Analyzer

*C=Operator'$

Frequency: SWR Maximum: (Used as alternate equipment.)

Frequency Range: SWR Maximum: Attenuation Accuracy:

Fundamental Frequency Range: Distortion Range: Distortion Accuracy: Low-Pass Filters: Oscillator Level: Oscillator Distortion: Oscillator Frequency Accuracy: f2%

hecks; P=Performance Tests: A=Adjustments; T=Troubleshooting

30

MHz

1.2

0.15

1.2

f0.4

-70 f2

30

and

3V

maximum into

<

to

1300

MHz

dB

20

dB minimum

dB

80

kHz

-70 dB

Hz to

600R

100

kHz

HP

8491A

Option

HP

8491A

Option

HP

89038

03

06

1-25

General Information Model

8901B

~

Instrument

Type

Audio

Synthesizer

Computing

Controller

Digital

Multimeter

nble

1-2.

Recommended Test Equipment

Critical Specifications

Frequency Range: 20 Hz to 400 kHz Output Level: +16 dBm (50R) maximum Frequency Accuracy:

Attenuator Accuracy:

Level Flatness:

f0.015 dB from 90 Hz to 10 kHz f0.3 dB from f0.07 dB from

Distortion: < -50

HP-IB compatibility as defined by ANSI Std MC1.l: SH1, AH1, T2, TEO,

Cl,

2,

3,

and

DC Range: 0 to 50V DC Accuracy: f0.01% at AC Range: 0 to lOOV AC Accuracy: f0.01 Ohms Range: Ohms Accuracy: fl%

4,5.

fO.l

O/O

fO.l

dB from 0 to 20 dB

50

Hz to 100 kHz

20 Hz to

dB from 20 Hz to 200 kHz

0

to 1 Mfl

200

kHz

1V

YO

at 2V and 2 kHz

IEEE

L2,

(2

Std 488 and the identical

LEO,

SRO,

PPO, DCO, DTO,

of

4)

HP 3336C

Option

HP 9825A and HP 98034A and HP 98213A HP 858 Option

HP 3455A

Suggested

Model

005

or

00;

Divider

Probe

(2

required)

Extender

Cable

Frequency

Standard

Oscilloscope

‘C=Operator’!

Divider Ratio: Input Impedance: 1 MR Input Capacitance:

No substitution

Accuracy:

Bandwidth: less than 3 dB down 0 to Sensitivity: 5 mV per division minimum Input Impedance: 10 MR and 500

Triggering: External and Internal

:becks;

P=Performance Tests: A=Adjustments; T=Troubleshooting

1O:l

<lo

is

recommended.

kO.l

ppm recommended

pF

100

MHz

HP 10040A

~ ~

HP 08901 -60179

House Standard

HP 1740A

1-26

Model

8901B

General

Information

Instrument

Type

Power Meter

Thermistor Mount

Power

Reference

Power Supply

Range

Cali brator

~~ ~

RF

Spectrum

Analyzer

Sensor

Module

Table

Power Range: 1 mW

Transfer Accuracy (input-to-output): 0.2%

SWR: 1.0550 MHz

f

Accuracy:

Power Output: 1 Accuracy: f(1.2% worst case +0.9% rss) for one year; 0 to

Output Range:

Calibration Functions: outputs corresponding to power displays

10

Calibration Uncertainty: f0.25% in all ranges

Frequency Range: Input Level: Display Range: 60 dB

Compatible with HP 8901 B Input SWR:

4.3,

4.5, at RF Input, RF Range 3

4.3, at RF Input, RF Range 3 with Modulation Analyzer’s

Special Function 1.9

0.5% at 50 MHz

pW,

100 pW, 1 mW, 10 mW, and 100 mW

ffO

at RF Input, RF Ranges 1 and 2

1-2.

Recommended Test Equipment

Critical Specifications

.OO

mW, factory set to f0.770, NBS calibrated

0

to 25 Vdc

0

to

2

GHz

dBm maximum

(3

50’

of

C

4)

Suggested

HP 432A

HP 478A-H75** or HP 478A-H76***

HP 435A

Option

HP 6215A

HP 11683A

HP 8559A and HP 182T

HP 11722A

Model

KO5

No

Service

Accessory

Kit

Signal

Generator

‘C=Operator’s “HP 478A-H75 must be calibrated at the National Bureau “‘HP 478A-H76 includes HP standards lab calibration to f0.58% at

substitution recommended.

Frequency Range: Output Level:

dBm

$19

+13 dBm maximum to 11 Output Level Accuracy: Frequency Accuracy: fl% Frequency Resolution: 1 kHz Modulation Capability: AM and FM

AM Depth: AM Accuracy: f10%

FM Range: FM Accuracy:

:hecks; P=Performance Tests; A=Adjustments; T=Troubleshooting

0

0.5

to 11

00

MHz

maximum to

to 95%

0

to 400 kHz peak deviation

500

fl

00

dB

MHz

f10%

of

Standards (NBS) for this accuracy.

HP 08901 -60287

HP 86408

Options

002

I

50 MHz (traceable to NBS).

001

and

rev.21

JUL87

1-27

General Information

Model

8901B

Instrument

Type

Signature

Analyzer

llable

External Count Range: to Because the signatures documented are unique to a given signature

1-2.

Recommended Test Equipment

Critical Specifications

15

MHz

(4

of

4)

analyzer, no substitution is recommended.

SWR

Bridge

Frequency Range: Impedance: Directivity:

50R

>40

dB

150

kHz to

1300

MHz

Connectors: Type-N

I

*C=Operator's Checks; P=Performance Tests; A=Adjustments; T=Troubleshooting

Accessory Type*

Adapter (Type N Male to BNC Female connectors)

620

Capacitor,

IC Extender Clip,

Resistor, Resistor, Resistor, Resistor, Tee (Coaxial, BNC, one Male and 50nLoad (Male,

pF

16

90901

O/O

121 001

YO

21 5001%

464001

O/O

BNC,

1

/4W

1

/4W

coaxial)

two

Female connectors)

I

*Accessories listed in this table are only those not already contained in the Service Accessory

Suggested

Model

HP 5005A

Wiltron

60N50

Recommended

HP

1250-0067

HP

01 60-3536

HP

1400-0734

HP

0757-0422

HP

0757-0274

HP

0698-0084

HP

0698-3155

HP

1250-0781

HP

1250-0207

Kit

HP

Use*

T

P

I

Part

08901-60287

1-28

Model 8901B

Installation

2-1.

INTRODUCTION TO THIS SECTION

This section provides the information needed information pertinent to initial inspection, power requirements, line voltage selection, power cables, interconnection, operating environment, instrument mounting, storage and shipment. This section also contains for removing the pull-out cards.

2-2.

INITIAL INSPECTION

Inspect the shipping container for damage. damaged, and the instrument has been checked mechanically and electrically. Procedures for checking electrical performance are given in Section or defect, or Hewlett-Packard office. If the shipping container of stress, notify the carrier carrier's inspection.

Section

2

INSTALLATION

to

install the Modulation Analyzer. Included

a

procedure for setting the internal HP-IB talk and Iisten address switches and a procedure

To

avoid hazardous electrical shock, do not perform electrical tests when

of

there are signs

(covers, panels, meters).

it

should be kept until the contents of the shipment have been checked for completeness

if

the instrument does not pass the electrical performance test, notify the nearest

shipping damage to any portion

If

the shipping container

4.

If

the contents are incomplete,

is

damaged, or the cushioning material shows

as

well as the Hewlett-Packard office. Keep the shipping materials for the

of

the outer enclosure

or

cushioning material is

if

there

is

mechanical damage

signs

is

2-3.

PREPARATION

Power

Requirements

The Modulation Analyzer requires a power source

66

Hz single phase. Option

only). Power consumption

FOR

USE

To

avoid the possibility

instrument at line voltages greater than

66

004

is

Hz.

200

greater than

3.5

mA.

of

Leakage currents at these line settings

also operates from

VA

maximum.

pbmimq

hazardous electrical shock, do not operate this

126.5

Vac with line frequencies

may

exceed

(+5%

to -10%) of 100, 120,220, or

48

to

440

Hz

single phase, 120 Vac,

240

(+5%

Vac,

to

48

to

-10%

2-

1

Installation Model 8901B

IWARN'NOI

This

is

a Safety

terminal).

the

main power source to supplied power cord set. Whenever impaired, any unintended operation.

If

this

instrument

sure

the

autotransformer's common terminal

pole of

the

Class

I

product (that

An

uninterruptible safety earth ground

the

product input wiring terminal-s, power cord,

the

product

power source.

must

be made inoperative and be secured against

is

to be energized via an external autotransformer, make

it

is,

is

likely

provided with a protective earth

must

be provided from

or

that

the protection has been

is

connected to the earthed

Power

Cables

IWARN'NGI

BEFORE CONNECTING THIS INSTRUMENT,

terminals

of the (Mains) power cord. The Mains plug outlet provided with not be negated

protective conductor (grounding).

This instrument is equipped with a three-wire power cable. When connected power receptacle, this cable each instrument depends on the country power cables available.

of

this instrument

a

protective earth contact.

by

the

grounds

the instrument cabinet. The type

must

be connected to

shall

use of an extension cord (power cable) without a

of

destination. Refer

the

protective conductor

only be inserted

The

protective action

to

Table

protective earth

in

a socket

must

to

an

appropriate ac

of

power cable plug shipped with

2-1

for the part numbers of the

2-2

Model

8901B

Table

2-1.

AC Power Cables Availiable (P/O ERRATA)

Installation

Plug

Type

250V

8

ho

250V

125V

1

oov

(Same plug as above)

250V

Cable

HP

Part

Number

-

8120-1351 81 20-1 703

81 20-1 369 81 20-0696

81 20-1 689 81 20-1 692

81 20-1 378 81 20-1 521

81 20-1 751

81 20-4753 81 20-4754

81 20-21

81 20-2296 81 20-3997 81 20-0698

Description

0

90°/STR BS1363A'

4

9oo/900

o

STRISTR

4 I NZSSl98/ASC112*

STR/90°

7

STR/STR'

2

STR/90°

STR/STR NEMA5-15P'

1

6

STR/90°

1

STR/STR

2

STR/STR

3

STR/90° STR/STR SEVl 01 1 79 Gray

3

04

1959-24507 Type 12

4

STR/90°

4

STR/90° STR/STR NEMA6-15P 90 Black United States,

6

Plug

Cable

90 Mint Gray United Kingdom, 90 Mint Gray Cyprus, Nigeria,

Cable For Use

Rhodesia,

Singapore

Austrailia,

New Zealand

II

79 79

80 Jade Gray United States, 80 Jade Gray Canada, Mexico,

90 Jade Gray U.S./Canada

90 Dark Gray Japan only

79

177 Gray

Mint Gray East and West Mint Gray Europe, Saudi

Arabia, Egypt, (unpolarized

manv nations)

Phillipines, Taiwan

Switzerland

Gray

Canada

in

0

00

250V

m

250V

Part number shown for plug

cable including plug.

rev.07JUL.87

81 20-2956 81 20-2957 81 20-3997

81 20-421 1 81 20-4600

8120-1860

81 20-1 575 8120-2191 81 20-4379

is

E

=

Earth Ground:

inc

90°/STR 79 Gray Denmark

3

4

9oo/900

4

STR/STR

I

7

STR/STR*IEC83-B1

8

STR/90°

STR/STR*CEE22-V1 Jade Gray (Systems Cabinet Use) STR/STR Jade Gray

0 8

8

-

identifier for plug only. Number shown for cable

d

L

=

Line: N = Neutral;

II

I

STR

=

79

Straight

I

Jade Gray Jade Gray

Black

is

I

HP

Part Number for complete

South Africa, India

2-3

Installation Model 8901B

Line Voltage and Fuse Selection

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

be sure the correct voltage and fuse have been selected.

Verify Figure 2-1,

that

the line voltage selection card and the fuse are matched

Line Voltage and he Selection.

hses may be ordered under HP operation

and

2110-0043,

1.5A

(250V normal blow) for 230 Vac operation.

to

the power source. Refer

part

numbers 2110-0083, 2.5A (250V normal blow) for

Operating voltage

in

module window.

is

shown

115

to

Vac

Selection

1.

Open cover door,

2.

Remove the Line Voltage Selection Card. Position the card so the line voltage appears at top-left corner.

3.

Rotate the

Push

FUSE

pull

the card

PULL

the

firmly

FUSE

into the slot.

lever

to

of

Operating Voltage and

PULL

its

normal position. Insert a fuse

Close the cover door.

HP-IB

Address Selection

The HP-IB address switches

Figure

2-1.

are

located within the Modulation Analyzer. The switches represent

five-bit binary number. This number represents the

In

controller must generate.

talk

only or to listen only.

addition,

two

Fuse

Replacement

lever and rotate to left. Remove the fuse.

of

the correct value

Line Voltage and Fuse Selection

talk

and listen address characters which

more switches allow the Modulation Analyzer

in

the holder.

an

to

HP-IB

be set

a

to

2-4

Model

8901B

Installation

Setting of the HP-IB address should be performed only

persons who are

aware

of

the potential shock hazard

by

service trained

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 address.

In t,,e Modulation Analyzer, the HP-Il3 (Figure procedure explains setting of the switches. Refer

addresses. In the factory, the address

In binary, this

2-2).

This address can be read by selecting BUS

is

01110;

1.

Disconnect the line (Mains) power cable.

2.

Remove any HP-Il3 cables or connectors from the HP-E3 connector.

3.

Remove the Modulation Analyzer’s

a. Remove the

screw within each foot.

b.

Unscrew the Pozidriv screw screw and

c.

Lift

off

4.

Locate the HP-IB address switch on the A14 Remote Interface Assembly near the front right of the

instrument. The A14 assembly may be recognized

circuit board extractor.

the

in

decimal

two

plastic feet from the rear of the

will

cause the top cover

top

cover.

talk

and listen addresses

ADRS

to

Table

is

it

is

set for a

14.

top

at

talk

address of

cover.

top

the center of the rear edge of the

to

pull away from the front frame.

as

are

selectable by an internal sw.xh

(Blue Key,

2-2

for a listing of the

“N”

and

cover by removing the pan-head Pozidriv

having one brown and one yellow printed

LOCAL).

a

listen address of

top

cover. This

The following

talk

and listen

“.”

(period).

is

a

captive

The Address

Figure Shown

is

2-2.

The HP-IB Address Switch Shown

01

11

0

in Binary

(14

in

Decimal)

as

Set

by

the Factory

With

Both Talk Only and Listen Only

Off

2-5

Installation Model

5.

Use a pencil Only (LON) condition. The switch switch (marked with toward the printed circuit board places

both set

all

set

cycle. (Setting

6.

Reinstall the

7.

Connect the line (Mains) power cable

to

the HP-IB connector.

8.

To confirm the address, confirm a in

the form AAAAA.TLS where

talk, listen, and service request

to

set the switches

a

“5”)

to

“l”,

the Talk Only setting will override.

“l”,

the Modulation Analyzer will output one byte (the

all

switches

top

cover by reversing the procedure in previous step

turn

talk

only or listen only setting, key

lbble

to

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

is

illustrated in Figure

is

the most significant address bit

it

in

its

“1”

position. If the TON and LON switches are

If

the address switches and the TON switch are

to

“1”

defeats HP-IB operation.)

to

the Line Power Module and reconnect the HP-IB cable

on the instrument and select BUS

in

21.0

AAAM

status.

2-2.

is

the HP-IB address

Allowable

HP-IB

Address Codes

2-2.

Facing the board, the left hand

(A5

in Table

status

2-2).

Setting a switch

byte)

each measurement

3.

ADRS

(Blue Key, LOCAL). To

SPCL. The display shows a binary number

in

binary and T,L, and S indicate

8901B

A

-

95

-

0 0 0

0

0 0

0

0 0

0

0 0

0

1

1 1 1

ire

-

94

-

0 0 0 0

0

0 0

1

1 1 1 1 1

0 0 0 0 0

8s

-

43

-

0

1

0 0

0

1 1 1 1

0

0 0 0

1

itcl

-

A2

-

0

1 1

0

1 1

0

1 1

0

1

0 0

1 1

0

‘S

-

A1

-

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

Talk

Address

Character

@

A

B

C

D

E

F

G H

i

J

K

L

M

N

0

P

Q

R

S

T

Listen

Address

Zharacter

SP

!

#

$

%

&

(

1

+

-

I

0

1 2 3 4

Decimal

Equivalen

0

1 2 3 4

5

6

7

8

9

10

11 12 13 14

15

16 17

18

19 20

2-6

1 1 1 1 1

1 1

1

-

0

1

-

1 1

1

0

1

-

0

1

0 0

1

0

1 1

-

1

0

1

0

1

0

1

0

1

0

1

-

U

v

W

X

Y

Z

r

\

1

..

Invalid

5 6 7 8

9

c

- -

>

Invalid

21 22 23

24

25

26 27 28

29

30 31

__

Model

8901B

SHOULD BE GROUNDED NEAR TERMINATION

OF

OTHER WIRE

TWISTED PAIR

OF

SIGNAL

GROUND

P/O TWISTED PAIR WITH

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

REN

010

DIO DIO DIO

ISOMETRIC THREAD

M3.5

-

x

0.6

11

10

9

8

7

6

8

7

6

5

SHIELD -CONNECT TO ATN EARTH

SRO

IFC NDAC NRFD DAV EO1 Dl0 4 DIO DIO 010

24-PIN MICRO-RIBBON

(SERIES

3

2

1

57)

GROUND

CONNECTOR

Installation

The Hewlett-Packard interface Bus logic levels are and the false

Programming and Output Data Format

Refer to Section 3 "Operation".

Mating Connector

HP 1251 -0293; Amphenol 57-30240

Mating Cables Available

HP 10833A, 1 meter (3.3 ft.), HP 108338 2 meters (6.6 HP 10833C 4 meters (13.2

Cabling Restrictions

1.

A

instrument.

(0) state is 2.5 Vdc to

ft.),

HP 10833D,

Hewlett-Packard interface

+5

Vdc.

Bus

system may contain no more than 2 meters (6.6

0.5

meters (1.6

TTL

compatible, that is, the true (1) state

ft.)

is

0.0

Vdc to +0.4 Vdc

of connecting cable per

rev.

15MAY89

Figure

2-3.

Hewlett-Packard

Interface

Bus

Connection

2-7

Installation Model 8901B

Interconnections

Interconnection data for the Hewlett-Packard Interface Bus

is

provided in Figure 2-3.

Mating Connectors

Interface Connector.

screws are metric.

Coaxial Connectors.

50R

BNC male connectors

in

US

MIL-(2-39012.

The application note, “Principles of Microwave Connector Care” (HP part number 5958-7442) can help you improve measurements and reliability. Suggestions in the application note will help you get the best performance from

connectors (in order

microwave connections (improving the accuracy and repeatability of all your measurements).

The HP-IB mating connector

Coaxial mating connectors used with the Modulation Analyzer should be the

or

50R

Qpe-N male connectors that are compatible with those specified

all

microwave connectors.

to

preserve their precision and extend their life) and how

It

will

is

shown in Figure 2-3. Note that

show what

to

look for when cleaning and inspecting

two

to

make the best possible

Operating Environment

The operating environment should be within the following limitations:

Temperature.. Humidity Altitude

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

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

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

.4570

-0°C

meters

<95%

(15

securing

to

+55”C

relative

000

feet)

Bench Mounting

The instrument cabinet

(The plastic feet are shaped raise the front of the instrument for easier viewing of the front panel.

has

plastic feet and fold-away

to

ensure self-aligning of the instruments when stacked.) The tilt

tilt

stands

for convenience in bench operation.

Rack Mounting

The Modulation Analyzer exercised when lifting to avoid personal injuv. Use equipment slides when rack mounting.

Rack

mounting information is provided with the rack mounting kits.

as

the instrument to paragraph 1-8, rack mounting the Modulation Analyzer, the

bottom of the instrument) must procedure that follows.

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

Additional Equipment Information

first

is

heavy for its size

Operating Information

be removed. To remove the pull-out card assembly, refer

(23.6

kg,

52

lb). Care must be

If

the kits were not ordered with

under

Mechanical Equipment Available.

pull-out tray (attached

Removal and Installation of Operating Information Pull-Out Cards

Steps for Removal.

card assembly:

1.

Remove the

2. Remove the Operating Information tray assembly by sliding the tray toward the rear of the instrument and then down.

3.

Remove the information cards by bowing them slightly in the middle and pulling

(away from the tray).

Follow the procedure below

two

front feet of the instrument.

to

remove the

Operating Information

stands

Before

to

pull-out

it

straight up

the the

2-8

Model 8901B Installation

Steps

card assembly:

2-4.

STORAGE AND SHIPMENT

for

Installation.

1.

Install the information card by bowing into the plastic guide slots near the front of the tray.

2.

Push the information card

3.

Place the information tray assembly between the rear feet of the instrument and slide it forward until the tabs are locked under the rear feet.

4.

Replace the front feet of the instrument.

Environment

The instrument should be stored in a clean,

to

apply

both storage and shipment:

Temperature.. Humidity Altitude..

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

Packaging

Original Packaging.

through Hewlett-Packard offices. attach number. Also mark the container FRAGILE the instrument by model number and full serial number.

a

tag indicating the iype of service required, return address, model number and full

Follow the procedure below

it

all

the way into.the tray.

dry

to

reinstall the

slightly in the middle and carefully guiding the edges

environment. The following environmental limitations

Operating Information

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

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

.15

300

Containers and materials identical

If

the instrument

to

assure careful handling.

to

those used

is

being returned

in

factory packaging are available

to

Hewlett-Packard for servicing,

In

any correspondence refer

-55°C ~95% relative

meters (50

pull-out

to

+75OC

000

feet)

serial

to

Other Packaging.

cially available materials:

1.

Wrap the instrument center, attach a tag indicating the service required, return address, model number and number.)

2.

Use a strong shipping container. A double-wall carton made of 1.9 MPa (275 psi) test

is

adequate.

3.

Use enough shock-absorbing instrument with cardboard.

4.

Seal the shipping container securely.

5. Mark the shipping container FRAGILE

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

in

heavy paper or plastic.

material

to

provide firm cushion and prevent movement

(75

(If

shipping

to

100 mm layer;

to

assure careful handling.

to

in

the container. Protect the front panel

a

Hewlett-Packard office

3

to

4

in.) around

or

full

material

all

service

serial

sides of

rev.

16JUN87

2-9

Model 8901B Operation

3-1.

INTRODUCTION TO THIS SECTION

This section provides advanced operating information for the Modulation Analyzer. Included in this

section are descriptions of all front

local operator’s checks, operating instructions, and operator’s maintenance.

Local Operation Section

Information regarding front-panel operation of the Modulation Analyzer is provided in the sections described in the following paragraphs.

to

refer Once familiar with the general operation of the instrument, use the

for

the separate

the most in-depth and complete information on operating the Modulation Analyzer.

Remote Operation Section

The Modulation Analyzer is capable

(HP-IB). Provided in this section are instructions pertinent considerations and instructions (including capabilities, address formats, input and output formats, the status byte, and service requests). and formats.

Section

3

OPERATION

and

rear-panel controls, connectors, and indicators, remote and

To

most rapidly learn the basic operation of the instrument,

Basic Operation and Application Guide

of

remote operation via the Hewlett-Packard Interface Bus

to

At

the end

of

the discussion

and/or perform the

Detailed Operating Instructions

HP-IB operation including

is

a complete summary of all codes

Operator’s Checks.

all

specific

HP-IB information concerning remote information

is

setting

Operating Information

in the paragraph,

discussed in Section

Detailed Operating Instructions.

Local Operation Section.)

pull-out card, and a list

2,

a summary

(Detailed Operating Instructions are described above in the

also

appears in several other locations. Address

of

HP-IB codes and output formats appears on the

of

relevant program codes for each function appears

Basic Functional Checks Section.

Basic finctional Checks

verify the proper operation of the Modulation Analyzer’s main functions and HP-IB capabilities. These checks can also be used measurements and HP-IB capabilities.

Basic Functional Checks

controlled functions are being properly executed by the Modulation Analyzer. The checks require the use of a sensor module, a signal generator, an oscilloscope, and interconnecting cables and adapters.

Basic Functional Checks

This series of procedures requires only an HP-IB compatible computing controller and an HP-IB interface and connecting cable. The

been

verified (for example, by performing the

are simple procedures designed

to

familiarize the first-time operator with basic Modulation Analyzer

Two

procedures are provided

of

the Modulation Analyzer.

of

the Hewlett-Packard Interface Bus (HP-IB)

HP-IB finctional Checks

Basic finctional Checks).

to

be performed by the operator. These checks

This procedure assures that most front-panel

assume that front-panel operation has

3-1

Operation Model 8901B

Detailed Operating Instructions Section

The

Detailed Operating Instructions

lyzer user. The instructions are organized into tabbed sections oriented

types. Besides information on the various measurements, the instructions contain individual discus-

sions of nearly all controls, inputs, and outputs. Also included are instructions for using the many

A

user special functions. instructions themselves.

guide

provide a complete operating reference for the Modulation Ana-

to

using the

toward

Detailed Operating Instructions

specific measurement

is

provided ahead of the

Other Sources of Operating Information

Pull-Out

flexible plastic reference sheets attached front panel. They contain a brief summary of front-panel operation and displays. cards functions. The cards show a simplified block diagram for the Modulation Analyzer and provide basic instructions for RF Power and AM and FM Measurements. The pull-out cards are intended reference for the user who already has a basic understanding of front-panel operation.

Supplemental Information.

its fullest capabilities, are contained Diagram” (in paragraph 1-10) is a fundamental description of what the Modulation Analyzer how the the way the Modulation Analyzer makes modulation measurements. provide a basis for applying the Modulation Analyzer

3-2.

OPERATING CHARACTERISTICS

The major operating characteristics of the Modulation Analyzer are provided

Description,

section in this manual.

3-3.

OPERATOR’S INFORMATION

Cards.

is

a

complete listing

it

works. This information supplements the block diagrams provided

The

Operating Information

Detailed Operating Instructions.

and Table

to

the Modulation Analyzer by a tray located beneath the

of

HP-IB codes,

Other information, pertinent

1-1

,

Specifications.

data,

in

Section

“Modulation Basics”

OF

THE MEASURING RECEIVER

For information on HP-IB capabilities, refer

and

Special finction Information Pull-Out Cards

Also

included on the

and error output formats, error codes, and user special

to

be

to

operating the Modulation Analyzer

1.

“Principles of Operation for a Simplified Block

is

and

on

the pull-out card and

(in

paragraph

to

various measurement situations.

1-11)

is

a discussion about

All

of this information helps

in

paragraph 1-6,

to

Remote

are

a

to

in

to

3-2

Fuses

For

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

a

250V

normal blow fuse of the same rating. Do not use repaired fuses

short-circuited fuseholders.

The only maintenance the operator should normally perform fuse located within the Line Power Assembly (A30). For instructions on how

1

and

to Figure 2-1, steps

Fuses can be ordered using HP part number 2110-0083, 2.5A (250V, normal blow) for 100/120 Vac

or

operation

2110-0043, 1.5A (250V, normal blow)

3.

for

220/240 Vac operation.

is

the replacement of the primary power

to

or

change the fuse, refer

Model 8901B Operation

Time Base

10 MHz

Input and Time Base

10

MHz

Output

[-I

Do

not apply greater than 20Vpeak (ac + dc) into the TIME BASE

MHz

INPUT

Do

not apply greater than 3 Vdc

BASE

10

or

MHz

damage to the instrument may result.

or

OUTPUT

greater than

or

damage to the instrument may result.

+20

dBm into the TIME

Description

Time Base

input is ac coupled and requires an input signal ievel greater than approximately 5000.

The time-base circuitry of the Modulation Analyzer automatically switches when an external time base

When using an external time base reference, the accuracy of of the external reference. Frequency-related measurements are most noticeably affected by time-base inaccuracy.

To determine whether the Modulation Analyzer has actually switched in the externally applied time base, select 15.1 time base is being used, the display will show

10

MHz

SPCL.

Input.

If

an

Provides an input for an external 10 MHz time base reference. This

0.5

Vpp. The input impedance

to

the external time base

of

sufficient amplitude

external time base

is

applied.

all

is

being used, the display

0.

measurements depends on the accuracy

wilI

show

10

1.

If the internal

is

If the Modulation Analyzer the time base oven is warm enough

0

if

the time base oven

To

drive several instruments from a single external reference, simply use a BNC tee at the Modulation

Analyzer’s TIME BASE 10 MHz INPUT.

If the internal time base fails, to TIME BASE to ON.

Time Base

002.)

output When driven from an external reference, the Modulation Analyzer outputs the internal reference (not

the external input signal). TIME BASE 10 MHz INPUT provides an input for time base reference. This input The input impedance is approximately 500fl.

10

MHz

Provides an output for the internal

(OV

to

greater than 2.2V into an open circuit).

is

10

MHz INPUT, then switch the instrument’s POWER

Output.

3-4. TURN-ON PROCEDURE

Before the Modulation Analyzer

of the power source,

paragraph

2-3,

is

using the internal, Option 002 time base, you can determine whether

to

create a stable source by selecting 15.0. The display

adequately warm. The display

an

external time base may still be used. Connect the external time base

(This output

is

ac coupled and requires an input signal level greater than 0.5 Vpp.

or

Power Requirements.

is

available only with the high-stability reference, Option

10

MHz reference. The output

is

switched on, it must be set to the voltage

damage to the instrument may result. Refer to

will

show Error 12

if

the time base

switch

is

a

to

500,

an

STBY

TTL

external 10 MHz

will

show

is

cold.

and back

compatible

a

Do

not apply greater than

damage to the instrument may result.

40V

(ac + dc) to the RF INPUT connector

or

3-3

Operation Model 8901B

Before the Modulation Analyzer

is

switched on, all protective earth terminals, extension cords, auto-transformers, and devices connected to be connected to a protective earth socket. Any interruption of the protective

earth grounding will cause a potential shock hazard that could result in

personal

For

injury.

continued protection against fire hazard, replace the line fuse with a 250V normal blow fuse of the same rating. Do not use repaired fuses short-circuited fuseholders.

The Modulation Analyzer

an

internal power supply

002) the supply energizes the internal reference oven.

Check

POWER

that

the line voltage setting matches the power source. (See Figure

in, set the

1.

has

is

activated. In instruments supplied with the high-stability reference (Option

switch to

a

standby state and

ON.

If

the power cable is not plugged 'in, follow these instructions:

an

he Selection.)

2.

Check that the fuse rating

and fie Selection.)

this section.

3.

Plug in the power cable.

4.

Set the

POWER

switch

is

appropriate for the line voltage used. (See Figure 2-1,

fise ratings are provided in the paragraph

to

ON.

NOTE

on

state.

Whenever the power cable

If

the Modulation Analyzer

it

shouM

or

is

plugged in,

is

already plugged

2-1,

Line Voltage and

Line Voltage

Operator's Maintenance

in

When the POWER switch

for approximately

operated.

3-5.

INSTRUMENT FEATURES

Front-panel controls, indicators, and connectors are illustrated and referenced The text for this figure describes the various functions of the Modulation Analyzer. description is

Rear-panel features are shown and referenced to text in Figure a quick reference for rear-panel signal levels and frequencies and also includes the impedances at the rear-panel connections.

The information in parenthesis

a

Operating Instructions

reference

relevant

is

set to

10

seconds after which the instrument

to

a

detailed operating instruction

at

the end of each feature summary provides the title of the

to

the feature.

ON,

all front-panel indicators

that

contains more details on this topic.

3-2.

The text for this figure provides

is

ready to be

to

light

text in Figure

At

the end of each

Detailed

3-1.

3-4

Model

8901B

Operation

38

37

36

35 34

33

32

3i 30 29

28

1

27

26 25 24 23 22

2

3456 7

8

9

10

11

12

13

14

15

16

21

20

19 18 17

Figure

3-1.

l+ont-Panel

Features

3-5

Operation Model 8901B

Front-Panel Features

The following list provides a brief description of each feature. The information the title of the

Detailed Operating Instructions

relevant to the feature. The index lists page numbers

in

brackets provides

for the instructions.

1.

MEASUREMENT keys enable the Modulation Analyzer measurement. [See

AM, FM,

@M,

RF Power, RF Input FYequency, Audio FYequency, Audio

to

make and display the selected

Distortion, IF Level, Tuned RF Level, RF FYequency Error.]

2.

Numeric Display shows measurement results, error codes,

or

instrument

or

Special Function

status.

3.

Display Annunciators indicate the measurement result units. They also indicate that some

measurement functions are enabled. All these annunciators are displayed when the Modulation

is

Analyzer

4.

AUTOMATIC OPERATION enables the Modulation Analyzer autorange to make the selected measurement. [See

5.

INSTR PRESET (Blue Key) configures the Modulation Analyzer to

first turned on.

to

automatically tune and

Automatic Operation.]

its

power-up condition. [See

Instrument Preset.]

6.

TRACK Analyzer. [See

7.

STORE (Blue Key) and RECALL (Blue Key) enable the Modulation Analyzer

up to eight measurement states. [See

8.

WATTS, pV, mV, and VOLTS keys (all used with the Blue Key) enable selection of different units

MODE

for

level measurements.

and

RF

FYequency Tuning.]

AUTO

TUNING (Blue Key) select the tuning mode of the Modulation

to

store and recall

Store/Recall.]

to

9.

MHz completes the keyboard entry

to

complete the entry of frequencies used with RF Power calibration factors. [See

nning, FYequency Offset Mode,

RF

of

frequencies for various functions. This key

Power.]

is

also used

RF FYequency

10. MODULATION OUTPUT/AUDIO INPUT connector provides either an output for the modulation recovered from the RF INPUT connector

an input for external audio signals

to

be

or

processed by the audio circuitry. The MODULATION OUTPUT annunciators indicate the type

of

recovered modulation available as the output. The AUDIO INPUT key selects whether the internally demodulated signal Analyzer’s audio circuitry. [See

Distortion

11.

7%

CAL FACTOR (Blue Key) causes the Modulation Analyzer to display the current calibration

and

Level, SINAD.]

or

an external audio signal

is

to be processed by the Modulation

Modulation OutputlAudio Input, Audio FYequency, Audio

factor for the selected measurement. This key is also used to complete the entry of calibration factors for various functions. [See

12.

DISPLAY FREQ (Blue Key) causes the Modulation Analyzer to display the RF frequency that

it tuned to last. [See

FFequency Offset Mode, RF Power Calibration Factors.]

13. SENSOR connector provides the input for the power sensor. [See

14.

kHz 0 and kHz 4 complete keyboard entry of frequency step-size (in kHz) for step tuning, change the frequency in the increments specified. [See

15.

DISPLAY FREQ INCR (Blue Key) causes the Modulation Analyzer to display the increment step-size. [See

RF Frequency Tuning.]

16. INPUT couples the RF input signal into the instrument. [See

AM Calibration, FM Calibration, RF Power.]

RF Power.]

or

RF FYequency Tuning.]

RF Input Requency.]

’

3-6

17. SPCL completes entry

of

Special Function codes that access additional instrument operations. Without a preceeding numeric entry, the SPCL key causes a display Functions

1

through

10.

[See

Special finctions.]

of

the status

of

Special

Model

8901B

18.

19.

20.

21.

22.

23.

24.

25.

Operation

(-)

(Blue Key) enables input

RANGE HOLD freezes the current ranges being used

data

to

be entered

as

a negative value.

by

the Modulation Analyzer. [See

Range Hold.]

Blue Key is a shift key that enables some keys

printed in blue can be selected when the key associated with

at

(The Blue Key flashes

the current measurement rate whenever it

DISABLE ERROR (Blue Key) disables Error

to

have

two

01

through Error

different functions. Any function

it

is

pressed after the Blue Key.

is

pressed.)

04.

[See

Error Message

Disable Control.]

LOG/LIN causes measurements to alternate between logarithmic and linear units. [See

LoglLin.

dB

or gain. [See RATIO and PREVIOUS

reference. [See

Operating Information

]

EXT ATTEN (Blue Key) enables level measurements

External Attenuation.]

RATIO

(Blue Key) cause the current measurement

Ratio and LoglLin.1

pull-out cards are quick operating references that list Special Function,

to

be offset with external attenuation

to

be compared

Ratio and

to

HP-IB, and Error codes, show a simplified block diagram for the Modulation Analyzer, and

RF

provide basic information for

Power

and

AMFM Calibration.

a

DETECTOR keys select the audio detector used

26.

to

measure the modulation.

[See

Audio Distortion and Level, SINAD.]

27.

1

kHz DISTN (Blue Key) and

make audio measurements on either 1 kHz

400

Hz DISTN (Blue Key) enable the Modulation Analyzer

or

400

Hz audio

signals.

[See

Audio Distortion and

Level, SINAD.]

CALIBRATION AMFM OUTPUT makes available a precisely modulated signal used

28.

the Modulation Analyzer’s AM or FM accuracy. [See

CALIBRATE and SAVE CAL (Blue Key) enable the Modulation Analyzer

29.

the resulting calibration factor for either

RF

initiates tuned RF level calibration operations. [See CALIBRATION RF POWER OUTPUT makes available a

30.

to

precisely determine the sensitivity of the external power sensor. [See

31.

SET

REF (Blue Key) is not a Modulation Analyzer function.

POWER switch applies power

32.

Preset.

ZERO causes the Modulation Analyzer

33.

sensor. [See PRE DISPLAY enables FM deviation

34.

]

RF Power.]

to

the Modulation Analyzer when set

to

cancel any dc offset that may be present in the power

to

be measured before

AM Calibration, FM Calibration.]

to

Power, AM, or FM. The CALIBRATE key

AM Calibration, FM Calibration, RF Power.]

50

MHz, 1 mW power reference

RF Power.]

to

ON. [See

or

after de-emphasis. [See

De-Emphasis.]

FM DE-EMPHASIS networks equalize pre-emphasized FM. [See

35.

FM De-Emphasis.]

Audio Detectors,

to

improve

calibrate and save

also

used

Instrument

FM

HP (High-Pass) and LP (Low-Pass) FILTERS limit the demodulated signal bandwidth. [See

36.

Audio Filters.]

LOCAL returns the Modulation Analyzer to keyboard control from remote (HP-IB) control.

37.

HP-IB Annunciators indicate remote operation status.

38.

3-7

Operation

Model

8901B

1

234

16 15 14 13 12 11 10

5

678

9

3-8

Figure

3-2.

Rear-Panel Features

Model 8901B

Rear-Panel Features

1.

AM OUTPUT produces an ac signal, whose amplitude dc component related

10 kR output impedance. [See

2.

FM OUTPUT produces an ac signal, whose amplitude a dc component related and

3.

RECORDER OUTPUT allows user-access

Output.]

4.

IF

OUTPUT produces a 150 kHz

-27

TIME BASE 10 MHz OUTPUT and INPUT. The input connector provides an input for an

5. external 10 MHz time base reference. The external input signal must be greater than 0.5V

peak-to-peak (into a

internal, high-stability

impedance). (Refer

to

the

IF

level. The output

AM Output.]

to

the

IF

frequency. The output

a

10 kR output impedance. [See

to

-3 dBm (500 output impedance). [See

500n

input impedance). The output connector provides an output for the

10

MHz reference. Output signal

to

paragraph 3-3.

FM Output.]

to

2.5 MHz modulated

Time

is

proportional to the AM depth, with a

is

dc coupled with a 16

is

proportional

is

dc coupled with a 16 kHz bandwidth

to

all internal measurement voltages.

IF

signal.

to

The output level ranges from

IF Output.]

is

TTL

compatible

Base

10

MHz Input and Time Base

Operation

kHz

bandwidth and a

the FM deviation, with

[See

Recorder

(500

nominal output

10

MHz Output.)

MODULATION OUTPUT/AUDIO INPUT

6. Option 001 instruments. Refer

Figure 3-1.

SENSOR

7.

to SENSOR referenced from Figure 3-1.

INPUT

8.

instruments. Refer F’use. 2.5A (250V normal blow) for 100 or 120 Vac.

9. Serial Number Plate. The

10. instrument configuration. The last five digits form the suffix

Line Power Module permits operation from 100, 120, 220, or 240 Vac. The number visible in

11.

the window indicates the nominal line voltage Figure 2-1,

FREQ OFFSET TTL OUT outputs a voltage that can be used

12. and out of the path between a microwave input signal and the Modulation Analyzer when the instrument

is

not selected

0

Hz. If the entered external LO frequency is less than or equal

+5V.

is

a rear-panel input for the power sensor supplied on Option

is

a rear-panel input for the RF input

to

INPUT referenced from Figure 3-1.

Line Voltage and he Selection)

is

in Frequency Offset Mode. The TTL output

or

while Frequency Offset Mode

If

the entered external LO frequency is greater than

to

MODULATION OUTPUT/AUDIO INPUT referenced from

first

four numbers and letter comprise the prefix

is

a

rear-panel output and input supplied on

001

instruments. Refer

signal.

to

which the instrument must be connected. (See

The center conductor

is

selected with an entered external LO value of

This input

1.5A

(250V normal blow) for 220

that

is

always

18

GHz, the TTL output

is

supplied on Option 001

is

unique

is

safety earth ground.

to

switch

OV

if

to

18 GHz, the TTL output is

or

that

denotes the

to

each instrument.

an

external mixer in

Frequency Offset Mode

is

Bequency offset Control.]

HP-IB Connector connects the Modulation Analyzer

13. remote operations. When the HP-IB is being used, the annunciators next as appropriate (REMOTE, LISTEN, TALK, SRQ).

to

the Hewlett-Packard Interface Bus for

to

the LOCAL key light

240 Vac.

3V. [See

REMOTE CONTROL RF SWITCHES enable the user

14.

can switch between the RF INPUT connector and the SENSOR connector. [See

to

build an internal sensor module that

Remote Control

RF Switch.]

LO OUTPUT and INPUT (Option 003 and Option Series 030 only). Option 003 provides an

15. output connector and an LO input connector. The LO output connector the Local Oscillator

(50R) nominal output impedance. The LO input connector provides an input for an external Local Oscillator. External input signal required

signal.

The output signal is 1.27

is

1.27 to 1301.5 MHz at approximately 0 dBm

to

1301.5 MHz at approximately 0 dBm

is

provided to output

LO

3-9

Operation Model 8901B

(50R)

nominal input impedance (LO Input and LO Output).

to

the internal LO signal

be routed

to

the LO input connector when no external

Two

jumpers are provided

LO

is

in

to

allow

use.

The Option Series connector and connected but the

output connector. [See

Do

not apply reverse power into the

instrument may result.

RFpower into the

16. CALIBRATION OUTPUT RF PWR and AMFM produces a rear-panel output for and AM and FM calibrators. This output standard front-panel connection. Refer CALIBRATION AMFM OUTPUT referenced from Figure 3-1.

030

instruments are provided with an

a

remotely controllable switch which selects between them.

signal

is

not in use, the switch routes the external LO signal back out the LO

LO

input connector, an

High Selectivity Measurements.]

u)

LO

Do

not apply greater than

INPUT

or damage to the instrument

is

supplied on Option

to

both CALIBRATION RF POWER OUTPUT and

OUTPUT

or damage to the

40

Vdc

or

may

001

If

an

external

+5

dBm

of

result.

instruments instead of the

LO

RF

output

LO

is

Power

3-10

HP

8901B

Modulation Analyzer

Basic Operation and Application Guide

HEWLETT

PACKARD

HP

89078

Modulation Analyzer

Basic Operation and Application Guide

OHEWLETT-PACKARD COMPANY 1986

EAST 24001 MISSION AVENUE, TAF C-34, SPOKANE, WASHINGTON, USA. 99220

Basic Operation

and

Application Guide Part

First

Ednion

Printed: Juiy

Number

1986

08901-90117

HEWLETT

PACKARD

Table

1.

Learning to Operate the

Chapter

each

2.

More about

of

Contents

HP

1

provides an easy step-by-step guide to learning

of

the

HP

8901Bs

RF

basic measurement capabilities.

Frequency and

Frequency Error Measurements

Chapter

enable you to adapt the

measurements to the special conditions

3.

More about Modulation and

2

describes the

HP

8901Bs

RF

Frequency and Frequency Error

special capabilites that

Audio Measurements

Chapter

that enable measurements to the special conditions

3

describes the

you

to adapt the Modulation and

HP

8901B’s

special capabilites

890

1B

of

your application.

Audio

of

you application.

4.

More about

Chapter

enable you to adapt the conditions

5.

Measurement Examples

Chapter

demonstrate how the versatility you to use it

Appendix Appendix

4

describes the

5

contains specific measurement examples that

A

B - Calibration Factors

Appendix C

RF

Power Measurements

HP

RF

of

your application.

in

a wide range

-

Installation

-

Other Publications

8901Bs

Power measurements to the special

of

special capabilites that

of

the

HP

8901B

measurement applications.

enables

Learnina

to

ODerate

I

The

HP 8907B

Easy

Solution

way

the

HP

This

Basic Operation and Application Guide a quick and easy way to learn to operate the Analyzer.

to

use the

Modulation, Audio, and

(2

through enable you to extend the operation of the recommend that you first familiarize yourself with referring to the reference chapters. Once you are comfortable with the basic operation of the instrument, it implement the many additional features that the

The hands-on approach in versatility of the actually puts the capabilities of several instruments at your fingertips. Many of the measurement capabilities included in the HP 8901B.

8907B'

is

designed to provide

HP

8901B Modulation

Chapter

HP

4)

2

will

provide you with all the information you need

8901Bs basic measurement capabilities:

RF

Power. The subsequent reference chapters

are devoted to the special functions and features that

HF'

8901B. We strongly

will

be easier for you to understand and

this

chapter demonstrates the extreme

HP

8901B. Placing the HP 8901B on your bench

of

the following products are

RF

Frequency,

Chapter

HP

8901B has to offer.

2

before

0

RF

Frequency Counter,

0

Modulation Analyzer,

0

Audio Analyzer,

0

RF

Power Meter,

The

HP

8901B combines many of the capabilities required for calibration, troubleshooting, and design HP 8901B's many special function capabilities enable you to adapt its measurements to the demands of a wide range of test conditions.

to 1 Hz resolution

AM,

FM,

and frequency, distortion, and level as accurate as the best

into

a single instrument.

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

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

@M

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

........

In

addition, the

(1-5) (1-9)

(1-15)

(1-18)

7-2

The

HP

8907B

7

1722A

Diagram

To get ready to learn to use the HP 8901B, connect the HP 8901B, an HP 11722A Sensor Module, and a signal generator together as shown in Diagram

If you are unpacking a new HP 8901B you will want to refer to the installation suggestiqns provided in

The procedures in this guide are written for use Sensor Module. There are many power sensors that can be used with the HP 8901B as well. (rather than a Sensor Module), refer to your HP 89018 Operation and Calibration Manual for information on which power sensors can be used and how to operate them

The

Once the HP 8901B

if

the calibration data for the Sensor Module you are using has been stored in the whether the correct calibration data has been entered into the HP 8901B. (Refer to the Sensor Module you are using has been entered into the HP 8901B.)

1-1.

Setup for

1-1.

Calibration Data

HP

8901B.

Appendix

B

Learning

Basic

Operation

Appendix A.

with

an HP 11722A

If

you

are using a power sensor

with

the

HP

8901B.

is

up

and running, you

Appendix

if

you are not certain that the calibration data for

B

contains a procedure for determining

will

need

to

first

detennine

1-3

The

Signal Generator

And

You

Note

The procedures in this guide are best performed using a signal generator that generates a single, stable steps from at least 100

AM,

also have

If

you are now sitting comfortably in front of your ready to begin. Start on the next page and follow the step-by-step guide to learning to operate the can increase both the ease and speed

FM

MHz

and (if available)

If you plan to selectively refer to portions

RF

signal that is tunable in 1 MHz

to

200

MHz.

The signal generator should

cPM

capability at a

HP

8901B. You will soon discover how the

of

many of your measurements.

of

1

HP

8901B, you are

Chapter

kHz

I,

rate.

rather

HP

8901B

than perform all of the procedures in sequence, we recommend

that you complete the procedures in the Frequency Counter

portion

of

this chapter firsf. The Frequency Counfer portion contains an introduction to the tuning and reset capabilities that are important to all of the

HP

8901Bs

measurements.

1-4

The

Front

--

----

Input signal not sensed

HP

up measurement

The

89016

Panel

Display

-

setting

Take a look at the

1.

brackets have been placed over each key group to help you quickly find the

function desired.

2.

Note the gold and blue keys.

"shifted" functions. selected by pressing the

3.

Switch the

powers up, it performs a self-test that includes turning on all front panel lights.

The HP 8901B keeps you informed of its operating status by the dashes and error codes it places in its display.

Interpreting the Dashes

4.

Adjust your signal generator to

to place the input signal is too low for the instrument to detect measurement mode.

5.

Set the signal generator to

input signal, it removes the

will see the HP 8901B replace the dashes indicate that the instrument is involved in internally setting up the measurement.

seconds, the instrument may be having difficulty input signal. (The HP 8901Bs Track Mode tuning, described later in this chapter, is typically a good choice for tuning to unstable signals.)

HP

two

dashes in its display. Two dashes indicate that the level of

8901B

If

the

HI'

8901Bs

As

this guide

gold

from

HP

8901B displays four dashes for more than a few

Front Panel.

These keys will enable you to select the

will

or

blue

key and then the desired function key.

STBY

to

ON.

-40

dBm.

0.0

dBm.

Once the HP 8901B detects an

two

dashes from its display. Sometimes you

two

Notice that label

demonstrate, the shifted functions are

Notice that as the HP 8901B

This causes the HP 8901B

in

its current

dashes with four dashes. Four

tuning

to an unstable

Interpreting Error Codes

6.

Press the

key location.) The have attempted to select an operating condition that with the measurement you are making. Error codes like this will keep you informed of both operator errors and input signal problems. The reference chapters (2, for each measurement along with recommended recovery actions.

CALIBRATE

HP

key.

(See the adjacent instrument diagram for the

89018

3,

and

will

display Error 21 to inform you that you

is

not compatible

4)

list the error codes that can be encountered

Frequency

Counter

1-5

Frequency

Measuring

RF

When your signal source testing requires an accurate

RF

frequency counter, the HP 8901B is a convenient solution. The HP 8901B makes it easy to tune to and measure the frequency of complex modulated signals.

If

you haven’t set-up your HP 8901B, Sensor Module, and

in

signal generator as shown need to do

so

in order to perform the following procedures.

Diagram

1-1

(page

1-2)

you

will

Adjust Your Signal Generator

RF

Frequency

Frequency Increment

Amplitude Modulation

1.

Press the FREQ key on the

an

HP

RF

counter. Notice that the HP 8901B automatically tunes to and

displays the frequency of

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

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

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

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

and

the green

8901B.

That‘s all it takes to configure the HP 8901B as

the

100

MHz

.1

MHz

0.0 dBm

Off

AUTOMATIC OPERATION

input signal (approximately

100

MHz; the absolute value depends on the accuracy of your signal generator and the accuracy of the HP 8901Bs time base reference.) Note also that AUTO TUNING (the green LED on the front panel) is on. This LED

you

know

lets

that the instrument is

in

its automatic tuning mode.

key

1

Hz

Resolution

Measurement Ranges

2.

To

increase the

7.4

SPCL * by pressing the digit keys 7

adjacent instrument diagram for key locations).

digit, simply press the

HP

8901B’s

CLEAR

display resolution to

0

4

and

1

the

Hz,

SPCL

key in

If you enter a wrong

key and begin again. Note that the

key (see the

key remains lit to show that a special function has been manually set.

*

If

the

HP

8901B

to

provide 1 Hz

display resolution.

counter resolution. Enter

displays Error

23

when you enter

7.1

7.4

SPCL

instead to select

SPCL,

it

is

not equipped

10

That’s all it takes to make an accurate frequency count on a stable signal throughout the

Input

Frequency

150

kHz

650

MHz

to

following

650

MHz

1300

MHz

ranges:

Amplitude

Range

-I-30

to

+30

to

-25

-20

dBm

SPCL

Hz

1-6

Frequency Counter

Choosing

Tuning

Mode

a

Manual Tuning Mode

Proper tuning is the key to making successful RF Frequency as well as other tuned measurements with the HP 8901B. The optimum tuning mode for

your measurement will depend on the characteristics of the input signal.

3.

Adjust your signal generator to

automatically tune to the new input signal. (Note that four dashes are

placed in the display while the HP 8901B is tuning to the input signal.)

Key

110

4.

the

keying in an RF frequency and pressing the the instrument’s Manual Tuning mode. The HP 8901B’s tuning is now set at 110 MHz.

The Manual Tuning mode can also be selected by pressing the itself. When you press the the HP 8901B’s tuning is set at the frequency currently being displayed.

Adjust your signal generator to

5.

an Error 01 to let you know that the input signal is no longer within the tuning range of the frequency set to.

MHz into the

MHz

key.

Note that AUTO TUNING (the green LED) is now

HP

MHz

110

MHz.

The HP 8901B should

8901B

by pressing the digit keys

MHz

key, you have selected

key without keying in a frequency value,

112

MHz.

The HP 8901B

(1

10 MHz) that the instrument was manually

will

1 1

MHz

display

0

and

off.

key by

By

Auto

Tuning Mode

Press the

6.

key.

(Notice that the AUTO TUNING, green LED is on again.) The HP 89018 is now tuned to the frequency of the input signal. (The Auto Tuning mode is the right choice when measuring a single, stable input signal.)

Track Mode

Press the

7.

input signal.

Increment your signal generator from

8.

steps.

frequency. (Track Mode is the right choice when you are measuring a drifting

or noisy signal.)

Measurement

Selected

RF

Freauencv.

Modulation or Single, drifty or noisy Audio

Frequency Error All Cases Manual Tuning

or

RF

I.

Power

Input Condition

Single, stable signal MultiDle. stable sianals

.,

sianal

>

Multiple, drifty or noisy

I

sianals

Blue

Shift

key and the

You

have placed the instrument back in its Auto Tuning mode.

TRACK MODE

The HP 8901B is now able to track the input signal as it changes

Tuning Mode

I

Auto Tuning

I

-

10

MHz Track Mode

>

10

MHz

Manual Tunina

Auto Tuning

Manual Tuning

I

Track Mode

key.

to

Select

AUTO TUNING (TRACK MODE)

In Track Mode, the HP 8901B is locked to the

112

MHz

to

100

MHz

in 1 MHz

HP

8901B

Tuning set at manually tuned frequency

-

Tuning locked to input signal

Operation

Frequency

Counter

1-7

Measuring

Frequency Error

Remember

The HP two-step process. Adjust your signal generator to

1.

Key

of

2.

Press the gold S key, and then the (both keys should remain lit).

the frequency difference (in kHz) between the manually tuned

frequency generator. (Note that the instrument displays a negative difference when the input frequency and a positive difference when the input frequency

8901B

100

MHz into the

your

signal generator

(100

makes checking

HP

MHz) and the actual output frequency of your signal

RF

frequency error a simple

8901B

(100

is

to manually tune it to the frequency

MHz).

FREQ

The HP

less than the HP

ERROR

8901B

8901B’s

100

MHz.

(FREQ)

is now displaying

is

key

manual setting

greater.)

Manual tuning is always the right choice when measuring Frequency

Error

because it establishes a known frequency reference. Also, the

Frequency

Error

measurement should only be made on a stable

input signal.

That’s all it takes to make Frequency Error measurements with

the HP

8901B.

10

Hz

Automatic

Resolufion

Reset

Operation

3.

To

display

the digit keys

remains lit to indicate that a special function has been invoked.

The HP functions to their automatic operating condition. The following procedures demonstrate the two reset functions.

4.

Press the green

the instrument back in its Auto Tuning mode (green you have disabled Special Function Pressing the

1

through the instrument to its Auto Tuning mode (not the best choice for Frequency Error measurements, remember). Note that the instrument is

still

10

Hz

counter resolution, enter

7

0

1

and the

89018

provides you with two ways to return its operating

AUTOMATIC OPERATION

10

to their Automatic Operation condition and returns

in the Frequency Error measurement mode (gold S key lit).

SPCL

key.

7.1

SPCL

by pressing

Note that the

key.

(SPCL

key no longer lit).

key resets Special Functions

You

have placed

LED

SPCL

on) and

key

1-8

Frequency Counter

instrument

70

Learn More...

Preset

5.

Now

press the Blue Shift key and then the green

(AUTOMATIC OPERATION)

key.

Note that the instrument is reset to

the Frequency measurement mode (gold

S

key

INSTR PRESET

off).

INSTR

resets the entire instrument to its power-up default condition.

Key

AUTOMATIC OPERATION

1.

Selects Auto Tuning Mode.

Function

1

I

Provides operator error recovery operating functions that

2.

Resets special functions

1

through

10

to their

can cause an error

condition. Automatic Operation condition.

INSTR PRESET

Resets functions.

Chapter

RF

2

in this guide provides reference information about the

Frequency and Frequency Error measurements and the

tuning capabilities. Refer to

all

operating

Chapter

Sets all operating

functions to their defined

2

when you want to find out

more about:

PRESET

Contribution

by

resetting the

HP

8901B's

0

Tuning

Modes

-

Further information about the

HP

tuning modes.

0

Extending Operation

enable you to adapt the

-

The special operating capabilities that

RF

Frequency and Frequency Error

measurements to the specific conditions of your input signal.

0

Help

-

Solutions to setup or operating problems encountered

RF

when making

Refer to

Chapter

Frequency

5

for examples of RF Frequency measurement applications.

or

Frequency Error measurements.

8901B's

Modulation Analyzer

1-9

Mo&/&jon

Ana'Yzer

Measuring

AM

The HP 8901B offers complete modulation analyzer capability to

AM,

FM

and

(PM

meet your measurements such as signal-to-noise and incidental can be made with ease and superb accuracy using the HP 8901B.

Set up your HP 89018, Sensor Module, and signal generator as shown in Diagram

1-1.

measurement needs. Even difficult

AM

and

FM

Adjust Your Signal Generator

RF

Frequency Amplitude Modulation Depth Rate

1.

Press the

PEAK+

approximately mode (green AUTO TUNING found and tuned to the modulated a good choice for making most modulation and audio measurements.)

2.

Key key.

input signal (green LED measuring modulation in the presence

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

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

in

100

The instrument is now manually tuned to the frequency of the

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

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

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

AM

key, the green

detector key.

50%.

Notice that the instrument

MHz

by pressing the digit keys

100 MHz

0.0

dBm

.....AM

.50%

1

kHz

AUTOMATIC OPERATION

The instrument should display an

is

in

the Auto Tuning

LED

on). The HP 8901B automatically

RF

signal. (The Auto Tuning mode is

1

0

and the

off).

(Manual Tuning is a good choice when

of

multiple

RF

input signals.)

key, and the

AM

index

MHz

of

Selecting a Detector

The HP 8901B provides six detector functions for measuring your modulation and audio signals.

Peak

Detector

3.

Press the

allows you to check modulation symmetry.

4.

Press both the

both detector keys at the same time allows you to display the average value of the positive and negative peak readings. (PEAK

5.

Press the

detector captures and holds the peak modulation level detected by the

Peak+

6. Increase the modulation depth

and then reduce it

continues Hold detector is ideal for detecting short modulation transients.

PEAK-

PEAK+

or

Peak- detector.

to

key.

Switching between the Peak+ and Peak- detector

PEAK+

display the maximum modulation level. The Peak

and

PEAK-

key and then the

of

back

to

50%.

Notice that the HP 8901B

keys at the same time.

PEAK

HOLD

the signal generator to

f/2).

key.

The Peak Hold

Pressing

75%

1-1

0

Modulation Analyzer

Average Detector

7.

Now

press the

You

have selected an average responding detector that is calibrated to read the approximately

RMS

8.

Press the below the

detector. The Average detector and the RMS detector are good choices when measuring noise or residual modulation where the generally more desirable than the peak value. The true-RMS detector can be used to measure modulation rates up to one more detector is also

rms

Detector

AVG

key to select the average-responding detector.

value of a sinewave. The HP 8901B should be displaying

35%

AM

with the signal generator set at

Blue

Shift

key and then the

RMS

key will come on).

digit

of resolution than the Average Detector. The true-RMS

a

good choice for measuring non-sinusoidal signals.

RMS (AVG)

You

have now selected a true-RMS

40

50%

AM.

key (the red

nns

value is

kHz and provides

LED

AM

Measurement

Ranges

Measuring

FM

Simply select AM and any of the above detector functions to make AM measurements within the following ranges:

1

RF

Carrier Frequency

150

kHz

to

9.999$99

10

MHz

to

1300

1.

Turn

off

AM

on the signal generator

deviation at a

2.

Press the

PEAK+

25

yellow FM MODULATION OUTPUT LED is lit. This indicates that the demodulated FM signal is available at the front-panel MODULATION OUTPUT/AUDIO INPUT port. (Connecting another audio analyzer to this demodulated signal while monitoring modulation with the HP 89018.)

detector key.

kHz. Notice that in the upper right comer of the instrument the

port

1

FM

key, the green

will enable

MHz

kHz

rate.

The HP 89018 should display a reading of about

I

Modulation Rate

20

Hz

to

10

kHz

20

Hz

to

100 kHz

and

turn on

AUTOMATIC OPERATION

you

to make audio measurements on the

25

kHz

key,

I

of

Max-

FM

and

Depth

99%

the

Modulation

Analyzer

7-7

7

Measuring

Pre-emphasized FM

Inserting Audio Filters

To accomodate your pre-emphasized with four separate de-emphasis filters. (Each labeled with a time constant corresponding to the

FM

signals, the

HI'

FM

DE-EMPHASIS

3

dB

89018

is equipped

key

comer frequency of

that de-emphasis filter.)

3.

Press the

press

after it has been de-emphasized. (The de-emphasized

it

75ps

FM

DE-EMPHASIS

too).

The display now shows the level of the demodulated signal

key (if the

PRE-DISPLAY

FM

signal is now

key is not lit,

available at the front-panel MODULATION OUTPUT/AUDIO INPUT port.)

4.

Press the

PRE-DISPLAY

key again to turn Pre-Display

off.

Notice that the display now shows the level of the demodulated

FM

signal before it

is

de-emphasized. The demodulated signal is now being applied to the de-emphasis filter after it is measured by the

HP

8901B.

(The de-emphasized signal

is

still

present at

the MODULATION OUTPUT/AUDIO INPUT port, however.)

5.

Press the function.

To

remove undesired signals such as harmonics, noise, and spurs

75ps

key again

to

turn

off

the

FM

De-emphasis

Repeat step 3 to select any of the four de-emphasis filters.

from the demodulated signal, insert the selectable high-pass and lowpass audio filters when making modulation or audio measurements. To minimize overshoot from square-wave modulation, such as

(FSK),

frequency shift keying

select the

>20

kHz Bessel Filter.

is

6. Press the

bandwidth of

300

HZ key and the

300

Hz

response of each audio filter.

7.

Press the 300

Hz

key and the

these filters.

to

3

kHz.

3

kHz key to set

Diagram

3

kHz

key

1-2

agah

a

typical measurement

shows the typical frequency

to remove

7-72

100

Modulation

Typical

50

Analyzer

Hs

High-Paar Filter

Reaponae

Typicel

300

Hr

High-Paas

Filter

Reaponae

80

-

E

I

5M

Y

1w

80

e

I

p

4a

0

50

100

MODULATION RATE

Typical

3

kHz

Low-Para Filter

1

2

MODULATION

FM

Measurement

150

(Hi)

Reaponre

3

RATE

BH2)

Diagram

Ranges

a,

E

::

$a,

Y

200

250

4 5

1-2.

0

Typical

The typical frequency response

That's all it takes to make out the following ranges:

2004mBwm1(Wo

MODULATION RATE

15

kHr

Low-Peas Filter

(H2)

Reaponae

of

each Audio Filter

FM

measurements and select

Typical

>20

kHr

Low-Paas Filter

MODULATION RATE

audio

Reaponae

IkHZ)

filters through-

RF

Carrier Frequency

150

kHz

to

9.99999

10

MHz

to

1300

MHz

Modulation Rates

20

Hz

to

10

kHz

20

Hz

to

200

kHz

Max.

40

kHz peak

400

Deviation

kHz peak

Modulation

Analyzer

1-13

Measuring

/n

Radians

In Degrees

(PM

Measurement

Ranges

oM

1.

Turn

off

the

FM

on the

modulation

(PM

capability, set modulation to FM, 10

2.

Press the

the

PEAK+

of

about OUTPUT LED is now lit to indicate that the demodulated is available at the MODULATION OUTPUT/AUDIO INPUT port.

(An

audio measurement device,

connected to this port for monitoring the demodulated audio signal.)

3.

Key

in

now displaying the phase deviation in degrees. (If the display is reading in dB, press the should display approximately

Select the measurements throughout the following ranges:

at the rate

(PM

key, the green

detector key.

10

radians. Notice that the yellow OM MODULATION

1.745

and then press the

@M

measurement mode to simplify your phase modulation

signal

of

LOG/LIN

generator

1

kHz.

(If your signal generator does not have

AUTOMATIC OPERATION

The

HP

8901B

such

RATIO

key to get

570

degrees for

and

kHz

should

as an oscilloscope, can be

key.

select

10

deviation at a

display a reading

The

HP

8901B is

YO.

The instrument

10

radians of

radians

1

key, and

(PM

(PM.)

phase

kHz

signal

rate.)

RF Carrier Frequency

150

kHz to

10

Maximum

I

400t

100

4

.1

.4u-l

100

9.999999

MHz

to

1300

Deviation

10

MHz

5

I

200

400

fc

5

MHz

1300

lk

MHz

2k

Modulation Rates

200

Hz to

10

kHz

200

Hz

to 20

kHz

4k 1Ok

:

MODULATION

RATE

(Hr)

1-14

Modulation

Analyzer

To

Learn More...

Chapter

modulation measurements. Refer to

3

in this guide provides additional information about the

Chapter

3

when you want to find

out more about:

0

Calibration

FM

measurements.

0

Extending Operation

-

The procedure

-

to

calibrate your

AM

and

The special operating capabilities that enable you to adapt the Modulation measurements to the specific conditions your input signal.

0

Help

-

Solutions to setup and operating problems encountered when

making modulation measurements.

Refer

to

Chapter

5

for examples

of

modulation measuremerit applications.

of

Audio

Analyzer

1-15

Audio

Measuring

Audio

Demo&/ated

Frequency

Analyzer

Audio

The HP 8901B enables you to measure your audio signal sources as well

RF

as your

distortion, and level measurements.

Set up your HP 8901B, Sensor Module, and signal generator as shown in Diagram

Adjust Your Signal Generator

RF

Frequency Amplitude Modulation Depth Rate

The HP 8901B enables you to accurately count the frequency of the internally-demodulated audio signal or of an external audio signal connected to the MODULATION OUTPUT/AUDIO INPUT port.

1.

Press the

Entering the AM measurement mode first, selects the measuring the AM input signal. The HP 8901B uses the last demodulator selected before entering an audio measurement mode to make its audio measurements. (Notice that the yellow AM MODULATION OUTPUT LED is lit. When you are making audio measurements, the MODULATION OUTPUT LEDs will

signal sources. Use the

1-1.

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

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

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

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

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

AM

key and then the green

show

you which demodulator

HP

8901B to make audio frequency,

100

MHz

0.0

dBm

AM

.50%

1

kHz

AUTOMATIC OPERATION

AM

demodulator for

is

selected.)

key.

External

Audio

2.

Press

the

gold

S

key

and then

keys should remain lit).

the frequency of the demodulated audio signal (approximately

1

kHz). The demodulated audio signal is also available at the

front-panel MODULATION OUTPUT/AUDIO INPUT port.

Press the OUTPUT port to

to make its audio measurements on an external audio signal source

connected to the AUDIO INPUT port. Press the key again to convert the port back to a modulation output and

continue measuring the internally demodulated audio signal.

AUDIO INPUT

an

AUDIO INPUT port.

key (key lit) to convert the MODULATION

AUDIO

The HP 8901B

FREQ

(AM)

is

now displaying

The HP 8901B is

AUDIO

key (both

INPUT

now

able

1-1

6

Audio

Analyzer

Audio

Frequency

Measurement Ranges

Measuring

Audio Distortion

That’s all it takes to measure intemally-demodulated or external audio frequencies throughout the

-~

Use the HP

Audio Max. External

Frequency Input Voltage

20

Hz

to

250

kHz

(usable

to

600

8901B

kHz)

to measure distortion on either a

following

ranges:

3

Vrms

400

Hz or a signal. Distortion measurements can be made on either the internally demodulated signal or on an external audio signal connected to the AUDIO

1.

Press the gold S key and the should remain lit).

distortion the

INPUT port.

of

the 1 kHz demodulated signal. Notice that

1

kHz annunciator

AUDIO DISTN

(FM)

key (both keys

The instrument is now displaying the measured

in

the display,

is

lit. The true-RMS detector is used to make

this measurement.

2.

Press the annunciator should be

to measure the distortion level

Blue

Shift

key and the

lit

in the display).

of

400

a

Hz

DISTN (PEAK-)

400

Hz

signal.

The instrument

key (the

is

now ready

1

kHz

400

Hz

Audio

Distortion

Measurement Ranges

Measuring

Audio

Level

That’s all it takes to measure audio distortion throughout the following measurement ranges:

0.01%

100.Oo/o

Display

Range

(-80.0

(0.00

of

port.

an

audio source

dB)

to

dB)

external

(Audio level

Audio Max. External

Frequency Input Voltage

400

Hz

and

1

I

The HP

8901B

kHz

is able to measure the

3

Vrms

I

rms

voltage level audio signals applied directly to the AUDIO INPUT measurements cannot

1.

When you need to measure audio level, connect

be

made on internally demodulated signals.)

to the AUDIO INPUT port.

I

2.

Key in

of

keys

3.

Press

30.0

SPCL.

the input signal. (Press the

pV

(4),

mV

(5),

any

measurement function key to exit the

measurement mode.

The instrument

Blue

or

Volts

(6)

to select the desired voltage units.)

Audio

will

display the rms voltage level

Shift

key and the voltage unit

Audio

Level

Analyzer

1-17

Learn

More...

Audio

Chapter

Audio measurement capabilities. Refer to

50

Hz

Frequency

to

40

kHz

3

in this guide provides additional information about the

Input Voltage

100

mV

to

3V

Chapter

3

when you want to know

more about:

0

Extending Operation

-

The special operating capabilities that enable you to adapt the Audio measurements to the specific conditions of your input signal.

0

Help -

Solutions to setup and operating problems encountered when

making Audio measurements.

Refer to

Chapter

5

for examples

of

Audio measurement applications.

HP

8901B

1-18

RF

Power

Meter

RF

Power Meter

RF

Calibration

Power

The HP 8901B provides you with the capability and accuracy best power meters. With a single keystroke, the HP 8901B autoranges to the input signal, measures its power, compensates for power

in

sensor flatness, and displays the results

Adjust Your Signal Generator

RF Frequency Amplitude Modulation

Like all power meters, the HP 89018 must first be calibrated. An internal Module and the HP 8901B’s Power Meter to an internal

1

.OO

mW reference signal. The following calibration procedure must be performed only one time to calibrate your Sensor Module. means you do not need to perform this procedure again as long as you are using the same Sensor Module. To ensure the highest possible measurement accuracy, allow the HP 8901B to warm up for at least thirty minutes before performing the calibration procedure.

1.

Press the

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

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

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

RF

Power Calibrator enables you to calibrate the Sensor

RF

POWER

key on your HP 8901B.

100

0.0

Off

the units of your choice.

MHz

dBm

50

of

MHz,

This

the

Error

Note

7

5

If

the HP 8901B is displaying Error to make RF Power measurements. (Refer to Calibration Factor Entry procedure before going on with this procedure.)

The calibration factors stored in the RF

Power measurements.

calibration factors are stored in the instrument, refer to Appendix

2.

Connect the HP 11722A Sensor Module to the OUTPUT

reference signal. (Disregard Error

Press the

3.

sensor reading to be displayed briefly. for any dc offset error inherent within the measurement system.

port

on the

ZERO

HP

key.

for

8901B

in order

If

HP

8901B.

Wait approximately 8 seconds for the zeroed

15,

it has not yet been configured

Appendix B and perform the

the Sensor Module

for

it to make calibrated, automatic

you

are not certain that the correct

This port outputs the

11

when it

The

HP 8901B

you

RF

POWER

is

displayed.)

are using must be

1.00

is

correcting

mW

B.

Remember

RF

Power

Meter

As

a

good rule of thumb, press the

10

minutes when making

RF

ZERO

key approximately every

Power measurements to compensate for any changes in the ambient operating conditions. The zeroing process is most efective if the

ZERO

key is pressed with the

HP

11722A

Sensor Module connected to the signal source being measured.

4.

Press the to be displayed. The HP 8901B

CALIBRATE

key. Wait for a stable, calibrated reference reading

is

creating a correction factor that

enables the instrument to equate its power measurement reading to the

1.00 mW reference.

5.

Press the

Blue

Shift

key

and

then the

SAVE CAL (CALIBRATE)

key.

This stores the calibrated reference in the instrument’s non-volatile memory.

6.

Press the

CALIBRATE

key again.

This

turns

off

the calibrator.

You

have

completed the calibration procedure.

7-79

Measuring

RF

Power

Changing frequency

7.

Connect

the

Sensor Module to the

signal

generator. The HP 8901B now calibrated to make accurate power measurements with the Sensor Module you are using. Erom now on, you need only repeat step

RF

maintain

1.

Press the

1000

-06W (1000 pW) with the signal generator set to 0.0 dBm.

2.

Press the logarithmic measurement readings to voltage units when you select the and a voltage units key

Shift

key and then the

3.

Adjust the frequency

Manual

4.

Key the new output frequency

Hp

8901B

key. The HP 8901B must be set to the same frequency as

Power calibration.

RF

POWER

LOG/LIN

(dBm)

Tuning

key. The instrument should read approximately

key to toggle the display reading between

and linear (watts) units. The instrument also converts

such

as

WATTS

of

the

(9)

signal

by pressing the digit keys

Blue

pV

(4),

mV

(5),

or

V

(6).

Press the

key to exit the voltage units mode.

generator to

of

the

signal

1

9

119

MHz.

generator into the

and

then

the

MHz

the

input

signal to enable the instrument to select the correct calibration factor.

2

to

Shift

Blue

is

key

7-20

RF

Power

Remember

Meter

Auto

Tuning

5.

You

can

also

allow the

input frequency by pressing the

and

the

AUTO

TUNING

displays the new input frequency, press the the

RF

POWER

If

the frequency of the input signal changes, always change the

key to re-enter the

frequency setting

6.

To

verify that the frequency setting

as

the frequency

and

then the

DlSP FREQ

of

HP

(TRACK

of

the

signal

8901B

HP

to automatically tune to the new

FREQ

MODE)

RF

Power measurement mode.

8901B as

of

generator, press the

(kHz

$)

key.

You

key, the

key.

Blue Shift

After the

MHz

key and then

HP

well.

the

HP

8901B

is the same

Blue Shift

can use this method to

check frequency tuning when in any of the measurement modes.

key,

8901B

key

RF

power

Measurement Ranges

To

Learn More...

From now on, simply select

RF

Power to make accurate, calibrated measurements throughout the following ranges using an HP Sensor Module:

Input Frequency

100

kHz

to

2.6

GHz

(HP

11722A)

I

Chapter

4

in this guide provides information about the HP 8901B’s

additional capabilities when in the

find

you want to

0

Calibration

0

Extending Operation -

out more about:

-

The RF Power calibration technique.

you to adapt the

Input Amplitude

-20

dBm

(10

pW)

to

+30

dBm

(1

W)

I

RF

Power mode. Refer to

I

The special operating capabilities that enable

RF

Power measurement to the specific conditions of

your input signal.

0

Help

-

Solutions to setup or operating problems when making

Power measurements.

RF

11

722A

Chapter

Power

4

when

RF

Refer to

Chapter

5

for examples

of

RF

Power measurement applications.

Special krncth Operation

1-21

Special

mnction

Opefation

Capability

To

extend instrument

operation

To select the instrument’s additional measurement capabilities

To access service-related operation information

Most measurements made with the

HP

8901B

require only a keystroke to invoke. There is no need to adjust levels, or select ranges because the HP

8901Bs

microprocessor determines the optimum instrument

settings automatically. However, in some applications it is desirable

to

override the automatic selection. Special functions provide you with manual control of instrument operation, selection of additional measurement modes, and the ability to extend measurement ranges.

The HP

Codes Application

1

to

10

11

to

40

to

8901Bs

These specihl functions enable you to select and adjust specific portions of circuitry within the HP functions to adapt the instrument’s operation needs of your application.

These special functions extend the measurement capabilities

37

of the HP functions. Use these special functions to make measurements such as SINAD, Audio Level, and LO Frequency. You can also use them for setting limits, setting references, and manipulating calibration data.

These special functions assist in servicing the HP

99

the instrument to display internal voltages and frequencies. Use these

special functions to verify operation of the HP (Refer to your special functions.)

special functions are described in the

8901 B

UP

89018.

by providing additional measurement modes and

8907B

Service

Manual

Use these special

to

the special

8901B.

for details on using service

following

8901

B

chart.

by enabling

The Special Display

Special function modes are selected first by entering the appropriate code (prefix, decimal point,

on

comer

1.

Key in

the front panel).

7.2

SPCL.

The

suffix)

SPCL

and then pressing the

SPCL

key (lower right

key remains lit to indicate that a special

function has been invoked.

2.

Now

press the

a number causes the HP have been set.

SPCL

key alone.

8901B

If

you previously entered the

Pressing the

to display which special functions

SPCL

key without entering

(1-10)

7.2

special function, a 2 should

now appear in the seventh display digit position. The display shows a zero

of

in each

the other display positions to indicate that these special functions

are still set to their automatic (default) operating condition. Use this capa-

bility to review or verify the special function settings that you have selected.

3.

Press the

SPCL

key again.

Pressing the

SPCL

key twice without

entering a number causes the instrument to display the special function

setting

(1-10)

actually being used.

(Note

that a

2

still

appears in the

seventh display digit position.) The other digits represent the settings

8901B

automatically selected for the measurement mode the HP

is

currently in. Use this capability when you are interested in knowing what settings the instrument

4.

Press the

CLEAR

is

currently using to make

its

measurements.

key to exit the special function display

and return to the previously selected measurement mode.

1-22

hEtiOn

Special Function Operation

The

Special

hfOffPlafiOn

PUll-OUf

card

The Special Function Information pull-out card enables an experienced user to quickly access special function operating information. A block diagram on the card shows which portions of the by special functions 1-10. A table of operating conditions for each special function functions description of their function. (Refer to the measurement reference chapters special functions can help you expand your measurement capabilities.)

11-39

(2

through

circuitry

(1-10)

are listed above the block diagram along with a brief

is provided below the block diagram. Special

4)

and the applications chapter

(5)

are controlled

to find out how

&fofs,

and

Dashes

Other

Help

Congfat&tions

The HP 8901B Modulation Analyzer keeps operating status by placing error and dash codes Operating Information pull-out card enables you to quickly access a

brief description of each code. The. measurement reference chapters

(2

through

conditions for each of the measurement modes. Each code listing includes a description and recommended recovery action. (Refer to reference chapters

You

are now familiar with each of the basic measurement capabilities of the HP 8901B. From now on, you can rely on the HP 8901B for making your frequency, modulation, audio, power, and level measurements. The rest

8901Bs

HP your applications goes beyond the contents of this guide, refer to the

HP

4)

in

this guide provide a listing of the errors and problem

(2

through

of

this guide will enable you to expand and extend the

measurement capabilities even further.

8901B Operation and Calibration Manual for further details.

4)

for help

in

solving your measurement problems.)

you

informed of

in

its display. The

If

the scope of

its

More about

RF

Frequency and

/n

This

Chapter

The Directory

Frequency

This

chapter introduces the HP that enable you to tailor its measurements to your specific test conditions. (To use these special capabilities effectively, you should first become familiar with the

basic operating capabilities and measurement ranges described in

Chapter 1 for the

This

chapter enables you to reference directly to the information you

are interested in. The information is organized into three subject areas.

0

Tuning

HP

0

Extending Operation

capabilities that enable you to adapt the conditions of your input signal.

0

Help -

encountered in

Use the directory diagram below to quickly locate the subject you are interested when appropriate. Use the look-up table to reference to the topics included for that subject.

Modes

8901B’s

Refer here for help in

in. A look-up table

Error

RF

Frequency and Frequency Error measurements.)

-

Refer here for further understanding of the

tuning modes.

RF

Frequency or Frequency Error measurements.

Measurements

8901B’s

RF

Frequency and Frequency Error

-

Refer here for the special operating

is

located on the first page of each subject area

special operating capabilities

HP

solving

8901B

setup or operating problems

to the specific

RF FREQUENCY

FREQUENCY

ERROR

TUNING

MODES

k=3

OPERATION

2-2

Tuning

Modes

Tuning

Auto

Modes

Tuning

If

You

Need

0

How

the Auto Tuning Mode operates

0

How

the Manual Tuning Mode

operates

0

How

Track Mode operates..

Auto tuning allows the HP input signal. It is automatically selected on Power-Up, or when the

AUTOMATIC OPERATION

mode is also selected by pressing the

TUN

I

NO

When the HP input signal below instrument then begins sweeping its local oscillator down to created

the IF passband. If no signal

instrument places

by

to

Know:

. .

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

key.

8901B

2.5

MHz.

the mixing of the

enters the Auto Tuning mode, it

2.5

h4Hz.

The

two

dashes in its display while it continues to sweep.

Refer

Auto

. .

. . . . . . . . .

.

. . . . . . . .

8901B

or

INSTR PRESET

If no signal

LO

continues sweeping until a difference frequency,

LO

and the

is

detected after multiple sweeps, the

.

Manual Tuning (2-4)

Track

to automatically find and tune to the

Blue

Shift

is

detected below

RF

to:

Tuning (2-2)

Mode

(2-4)

key

is

pressed. Auto Tuning

key and then the

first

checks for an

2.5

MHz,

(LO)

from

1300

input signal, appears within

AUTO

the

MHz

When a signal does appear within the IF passband, the instrument performs

is

a series of tests to determine whether the signal it has found

This

appropriate signal to tune to. Tune to the fundamental in harmonically-rich specbums or to a carrier

AM.

with high-depth the correct frequency, the oscillator to ensure high-stability, low-noise measurements. If the input signal changes after the Tuning mode, the Tuning mode

Keep in mind that certain input for the HP choice when these conditions exist. For a refer to

is

8901B

Table

2-1. Input Conditions that

Once the instrument determines that it

HP

LO

has been locked to the

LO

automatically begins the sweep search again. Auto

a good choice when measuring a single, stable input signal.

to Auto Tune. The Manual Tuning mode is a good

testing enables the HP

89018’s

LO

signal

conditions can make it difficult

is locked to an internal crystal

listing

May

crystal

of these conditions,

Require

Manual

the

89018

to Auto

is

tuned to

oscillator in Auto

Tuning.

Input Condition

Table

2-1.

Input Conditions That May

Description

HP

8901B’s

Require

Manual Tuning.

Response

Tuning

Recommendation

Modes

2-3

Multiple input signals

Level

of

2nd or 3rd

harmonic is greater

-10

than

Input signals above

measurement

range

dBc*

(1300

MHr).

For input signals whose amplitudes are all between

+30

-25 dBm and and are within approximately

15

dB of one another, the

8901

HP to the signal at the highest frequency rather than the signal with the highest level.

The HP these as fundamental signals and tune to the signal at the highest frequency.

Harmonics from the HP

8901B’s

signals above produce beat frequencies within the IF passband.

B may auto tune

8901 B

LO may mix with

dBm,

may interpret

1300

MHz to

Instrument will measure and display characteristics of input signal at the highest frequency.

Instrument may measure and display characteristics of

input signal at the

highest frequency.

Instrument may measure and display characteristics

1300

of signal above

MHz.

If

the desired signal is not the highest-frequency signal, manually tune to

the desired frequency or

place a bandpass filter at

8901

B’s

the HP

block the unwanted signals.

If

the desired signal is not the highest-frequency signal, manually tune to

the desired frequency.

Manually tune to the RF signal below place a low pass filter at the

8901

HP unwanted high frequencies.

B’s input to block thc

input to

1300

MHz, or

Low-rate, high-

deviation FM

Low-level carrier

with low-rate, high-

depth (percentage) amplitude modulation

dBc = decibels referenced to the carrier level.

While auto tuning, the

8901

B

rate

(c

may mistake

20

Hz) high-

(>

400

kHz)

8901B’s

HP

low

deviation

FM for signal drift.

The AM may cause the carrier level to move in and out of the HP

measurement range.

Instrument may continuously

display four dashes.

Instrument may continuously

display two dashes or

it

may alternately display

or two dashes then four dashes.

0

MHz,

Manually tune to the carrier frequency or remove the FM until the instrument has auto tuned to the signal.

Manually tune to the carrier frequency to increase measurement sensitivity. (Refer to

increasing

this chapter to extend the measurement range further.)

Sensitivity

in

2-4

Tuning

Modes

Manual Tuning

Track

Mode

The Manual Tuning mode allows you to set the at a desired frequency.

frequency and then pressing the

This

is done by keying in the desired

MHz

key. The manual tuning mode can also be entered by pressing the locks the instrument at the frequency it

In Manual Tuning mode, the HP to the HP

8901B’s

present or not. Once the

internal crystal oscillator whether an input signal is

LO

is locked to the crystal oscillator in Manual

is

8901Bs

Tuning mode, tuning does not change unless a new frequency

MHr

in and the using one

key is pressed, or tuning

of

the increment keys,

tkHz

is

or

HP

MHz

key by itself.

8901B’s

tuning

This

currently tuned to.

local oscillator (LO) is locked

is

keyed

incremented up or down

UkHz.

(Set an increment by keying in the desired increment value and pressing one of the increment keys. The instrument

one of the increment keys

AUTOMATIC OPERATION

the

will

increment by the keyed-in value each time

is

pressed.) Press the

AUTO TUNING

key to exit the Manual Tuning mode.

key or

Manual Tuning is a good choice when measuring an input signal whose amplitude is less than

RF

multiple

signals are present.

-25

dBm or unstable, or where

If

the input signal is

drifty,

however, it may be necessary to select the Track Mode function.

The Track Mode function enables the signals from

10

MHz to

1300

MHz. Track mode can be selected with either Auto Tuning or Manual Tuning by pressing the key.(A drifting signal will cause the in its display when Auto Tuning is selected or Error

HP

8901B

to track drifting input

TRACK

MODE

to place four dashes

01

when the

instrument is manually tuned.)

In Track Mode the Local Oscillator

(LO)

is

locked to the input signal.

The instrument remains locked to the signal throughout each of the

LO’S

tuning octaves. When an input frequency change causes the to cross into a new octave, lock may be broken. If the instrument in Auto Tuning Track Mode, the HP signal.

the instrument

is

in

Manual Tuning Track Mode, the LO

If

return to the manually tuned setting after lock

boundaries occur at

2.5, 5,

10,

Track Mode is the right choice when measuring

8901B

20, 40,

will relock to the input

is

broken. The octave

80, 160, 320,

640,

drifty

input signals.

and

1280

LO

is

will

MHz.

However, certain operating limitations are present when using Track Mode. These limitations are listed below:

0

Not allowed below

0

Not allowed with

0

Raises residual

0

Attenuates low-rate

FM

10

MHz

455

kHz

level

FM

on input signal

IF

(use

for

FM

rates

>1

kHz only)

Table

2-1.

Input Conditions That May

Require

Manual

Tuning.

Tuning

Modes

2-3

Input Condition

Multiple input signals

Level

of

2nd or 3rd harmonic is greater than

-10

dBc*

Input signals above measurement

(1300

range

MHz).

Description

For input signals whose

amplitudes are all between

-25

dBm and +30 dBm,

and are within approximately

15 dB of one another, the

HP 8901 B may auto tune to the signal at the highest frequency rather than the signal with the highest level.

The HP 8901 B may interpret these as fundamental signals and tune to the signal at the highest frequency.

Harmonics from the HP 8901B’s signals above 1300 MHz to produce beat frequencies within the IF passband.

LO may mix with

HP

8901B’s

Instrument will measure and display characteristics

of input signal at the

highest frequency.

Instrument may measure and display characteristics

Response

of input signal at the

highest frequency.

Instrument may measure and display characteristics

of signal above 1300 MHz.

Recommendation

If the desired signal is not the highest-frequency signal, manually tune to the desired frequency or place a bandpass filter at the HP 8901 B’s input to block the unwanted signals.

If

the desired signal is

not the highest-frequency

signal, manually tune to the desired frequency.

Manually tune to the

signal below 1300 MHz, or place a low pass filter at the

HP 8901 B’s input to block th’ unwanted high frequencies.

RF

Low-rate, highdeviation FM

Low-level carrier

with low-rate, high-

depth (percentage) amplitude modulation

dBc = decibels referenced to the carrier level.

While auto tuning, the HP 8901 B may mistake

(c

20

(>

Hz) high-

400

kHz)

low rate deviation FM for signal drift.

The AM may cause the carrier level to move in and out of the HP 8901B’s measurement range.

Instrument may continuously

display four dashes.

Instrument may continuously

0

display two dashes or

it

may alternately display

or two dashes then four dashes.

MHz,

Manually tune to the carrier

frequency or remove the

FM until the instrument has

auto tuned to the signal.

Manually tune to the

carrier frequency to increase measurement sensitivity. (Refer to lncreaslng this chapter to extend the measurement range further.)

Sensitivity in

Extending Operation

2-5

Extending Operation

If

You

Need

to

Frequency

How

to tune to the input signal when other are present..

0

How

frequency

How

input signals above

How

input signals below

RF

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

to retune to a

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

to tune to a noisy input signal.

to track a

to measure the frequency of

Amplitude

Know:

signals

new

drifty

1300

150

or

harmonics

input

input signal

MHz

......

kHz

......

Refer

Increasing Selectivity

Changing Frequency

Noisy Signal

.

Driffy

Frequency Overrange

Frequency Underrange

to:

Signal

(2-5)

(2-6)

(2-7)

Increasing Selectivity

How

to tune to an input signal whose

amplitude is very unstable..

The HP the fundamental in a harmonically-rich spectrum as long as the fundamental

is at least

HP 8901B will also auto tune to the input signal all not meet these criteria, the HP 8901B may have desired input signal. desired input signal, manually tune the HP 8901B to the input frequency by keying in the frequency of

To minimize the possibility of unwanted low-frequency, harmonic, or spurious signals entering the

bandpass

combination selections.

8901Bs

Auto Tuning mode is able to automatically find and tune to

10

dB

above the level of the second and third harmonics. The

non-harmonically-related

If

the instrument does not display the frequency of the

IF

filters can be selected. Table

........

RF

signals.

the

input signal and then pressing the

IF

passband, a high-pass

Unstable Signal

if

it is at least

If,

however, your input signal does

difi5culty

2-2

shows the possible filter

(2-7)

30

dB above

auto tuning to the

MHz

key.

RF

filter and

2-6

Extending Operation

RF High-Pass

Filter

(5.25

MHr)

OUT

IN

Table

2-2.

Filter Configurations

Filter

Automatic

2.5

MHz

Low-Pass

2.5

MHz

Low-Pass

2.5

MHz

Low-Pass

2.5

MHz

Low-Pass

Selection

1.5

455

MHz

kHz

3.0

3.1

~ ~

3.2

3.3

3.4

3.6

3.8

SPCL SPCL

__

SPCL SPCL

SPCL

Changing

Noisy

Frequency

Signal

Although the HP 8901B is not designed for swept measurement applications, its Auto Tuning mode does enable it to automatically search for the input signal after the frequency of the input signal is changed. The instrument will place four dashes in its display while it is searching for the input signal.

Image Signals

If

the frequency of the signal is increased

twice the IF signal frequency (for example,

by

an increment equal to

2

x

1.5

MHz), the image

frequency will appear within the IF passband. If the switching speed

will

not

of the input signal is too fast, the HP 8901B

detect a change in the input frequency and will continue to erroneously display the previous frequency.

Shift

key and then the

If

you suspect that this has happened, press the

AUTO TUNING

key after the input frequency

Blue

has changed. This causes the HP 8901B to retune to the input signal.

Excessive noise or low-rate (below

400

kHz) FM on the carrier signal can make it difficult for the HP 8901B

to auto tune to the carrier.

If

the HP 8901B indicates it is having

20

Hz), high-deviation (greater than

you know that your input signal is noisy, or if

difficulty

setting up the measurement

by continuously displaying four dashes, manually tune the HP 8901B

of

to the frequency the input signal and then press the

the input signal. Simply key in the frequency

MHz

key.

not display a measurement reading, press the

If

the HP 8901B does

TRACK

MODE

of

key.

Extending

Operation

2-7

Drifty Signal

Frequency Overrange

Frequency Underrange

A drifty or noisy input signal can cause the instrument to continuously

or

display four dashes (Auto Tuning mode) mode). Press the

TRACK

MODE

key to select the wide-IF-bandwidth

display Error 01 (Manual Tuning

track mode function. Track Mode can be selected with either the Auto or Manual tuning modes. Note that the Track Mode function reduces the low frequency response of modulation measurements and increases

the level of residual modulation. (For details on the capabilities and

Track

Mode

limitations of Track Mode operation, refer to

in this chapter.)

There are three techniques for extending the HP 8901B's frequency range above

MHz: internal harmonic

mixing,

external local

1300

oscillator and mixer down-conversion, and down-conversion with a spectrum analyzer. All three techniques extend the measurement capabilities of the HP 8901B to microwave frequencies. (Refer to

Chapter

If

range, the instrument

limit of the RF Frequency measurement is can extend this measurement range

Audio Counter. Connect

OUTPUT/AUDIO INPUT port and press the should remain lit). Press the gold Audio Counter will accurately count input signals from

5

for measurement examples using these tuning techniques.)

the input frequency is below the HP 8901B's frequency measurement

will

display

your

Error

10. The specified low frequency 150

kHz.

However, you

to

20

Hz

by simply selecting the

signal source to the MODULATION

S

key and the

AUDIO INPUT

AUDIO

FREQ

20

Hz to

key (key

key. The

250

kHz.

Unstable Signal

If

you

are measuring an input signal whose

above

-20

dBm to

-25

dBm, (for example, a low level signal with

high-depth AM or a signal that

is

being pulsed on and

RF

level does not remain

off),

select the

Manual Tuning mode by keying in the frequency of your input signal and

MHz

pressing the

key. In Manual Tuning mode, the instrument

locked at the manually tuned frequency after the input signal

will

is

turned

remain

off.

NO

Sensor

Help

Module

If

You

Need to

0

How

to measure frequency without

using

a Sensor Module..

How

to make automated frequency

measurements.

How

to connect an external time base

Know:

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

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

Refer

No

UP-IB

Time Base

to:

Sensor Module

(2-8)

Measurement

0

How

to interpret an error code, dashes

or

questionable measurement..

A

Sensor Module is not required for making

Frequency Error measurements. To make measurements without a

Sensor Module, simply connect a

the HP 8901B’s

INPUT

port to the output of your signal source.

......

50R

Solving

Problems

RF

cable and Type-N adapter from

Measurement

(2-9)

Frequency or

Time

HP-/B

Base

The HP 8901B enables you to fully automate your measurements. Refer to your HP 8901B Operation and Calibration Manual for setup and programming information.

A

time base input input allows you time base. The time base switches to the external time base and turns when an external time base at the input. To verify that an external time base is being used, key in

15.1

SPCL.

is

base

being used

is

provided on the rear panel of the

to

connect the HP 8901B to an external 10

circuitry

The instrument will display a

or

a

0

if

the internal time base

within the HP 8901B automatically

off

its time base output

of

sufficient amplitude

1

if

HP

8901B.

MHz

(0.5

Vpp) is applied

the external time

is

being used.

This

Solving Measurement

Problems

Help

The

HP

8901B has been designed to feed back information about its

operating status. When the

HP

89018 detects that the input signal or

operating conditions are preventing it from making an accurate, reliable

measurement, it alerts you by placing an error or dash code in its display.

2-9

The circumstances that can cause the

two

classified into one of

0

Input Problem,

0

Operating Problem,

categories:

caused by input signal conditions, or

caused by the selection of incompatible

HP

8901B to display an error code are

operating functions.

Certain errors are caused

only

by

an operating problem,

The errors that can be caused can be caused

If

your instrument

Table

2-3.

onZy

RF

Frequency

is

only

by

an input problem,

other errors are caused

and some errors can be caused by either.

only

by

an operating problem

an input problem

are listed in the chart below.

and the errors that

displaying one of these errors, proceed

and

Frequency Error, Error Codes,

directly

and take the

recovery action recommended.

Error

If

you

Input

Problem

I

1

did

not find your error listed in the

10

I

09,

Operating

Problem

12,

20

thru

chart

24,

or

26

or

if

your instrument displaying dashes or a questionable measurement, continue with the following procedure.

to

is

1.

Press the

function settings that can cause the

2.

Compare the operating status of your

AUTOMATIC OPERATION

green

AUTOMATIC OPERATION

key with the following condition descriptions.

key.

This cancels all

I-IP

8901B to display an error code.

HP

8901B

after

pressing the

After you have identified the description that best describes your instrument’s condition, take the action recommended for that condition.

2-70

Help

Same Error

No

Error

New Error

Remember

If the error or reading remains the same after the

TION

key has been pressed, the error is being caused by an input problem.

2-3

Look up the error code in Table

and take the action recommended for

AUTOMATIC OPERA-

"Input Problem".

If

the error goes away after the been pressed, the error was caused by an operating problem. up the error code in Table

AUTOMATIC OPERATION

2-3

and take the action recommended for

key has

Look

"Operating Problem".

If

the error is replaced by a different error or dash code after the

MATIC OPERATION

key has been pressed, the original error was being

AUTO-

caused by a combined input problem and operating problem. Look up the

after

the

error code displayed by the instrument

AUTOMATIC OPERATION

key was pressed. Take the action recommended for "Input Problem".

Because

flexibility of the

recovery actions

determine the cause

of

the wide variety

HP

8901B,

for

each error code. After using the table to

of

input signals and the operating

it is not possible to list all

the problem,

you

may discover other error

recovery procedures that are better suited to your application.

Display

Code

Questionable Measurement

01

Table

2-3.

RF

Frequency

Problem Description

and

Frequency Error, Error Codes

Instrument does not display frequency of the input signal.

Input signal level out of measurement range.

and

is

attempting to set

up

measurement.

Continuous display indicates instrument

I

is

having difficulty-tuning to input signal

I

IF

signal within

IF

passband but not centered well enough to guarantee measurement accuracy (due to manual tuning).

High

AM

depth

(>95%)

on low-level carrier.

____

~~

Input Problem

Check tuning mode.

Refer

to

Selectivity

Drifty

Increasing

(2-5)

Signal

(2-7).

or

Adjust input signal

level

or change

measurement Manually

input signal.

Noisy Signal

tune

Refer

(2-6).

sensitiviq

to

Increase input signal

level or decrease AM.

(1

of

2)

Operating Problem

Recheck

conditions being used.

Decrease attenuation.

Re-check operating conditions

Press the MHz key

to center

in

IF

passband.

If

problem persists,

signal may be

drifting.

Drifty

Refer to

Signal

operating

RF

being

used.

IF

signal

(2-7).

Table

2-3.

RF

Frequency and Frequency Error, Error Codes

(2

of

2)

Help

2-1 1

Display

Code

02

03

06

09

Problem Description Input Problem

Input circuits overdriven. Increase RF

Input circuits underdriven. Decrease RF

Input circuits overdriven.

High stability time base problem (Option 002 instruments only).

Frequency

measurement range.

Indicates internal time base oven cold lODtion 002 instruments onlv).

IF level not within its measurement range.

Frequency entered exceeds measurement range.

Invalid entry.

Invalid Special Function prefix entered.

Invalid Special Function suffix entered.

of

input signal is not within

input attenuation.

input attenuation. Input level exceeds

7

Vrms

(1

Decrease level

of input signal.

Adjust frequency of input signal to within measurement ranae, or increase measurejnent range. Refer to Frequency Overrange

(2-7)

Underrange

Input signal level during reference measuremeni must be between

1.25V and 2.50V. (Option

W

and Frequency

030

peak).

(2-7).

only.)

Operating Problem

Increase RF attenuation.

Check internal time base for malfunction.

Wait for oven to warm

for hiahest accuracv. (When making Ratio

measurements, allow instrument to

complete the reference

measurement.) Re-enter frequency

within measurement

range. (In Ratio mode, reference measurement

of zero is invalid.)

Check compatibility of

function@) with selected

measurement mode.

Check Special Function

number and re-enter.

Check Special Function number and re-enter.

E

More about Modulation and

Audio Measurements

/n

This

The

Chapter

Agilent 8901B Specifications Sheet

Specifications and Main Features

Frequently Asked Questions

User Manual

INTRODUCTION TO THIS MANUAL

Service Manual

Serial Numbers

HEWLETT-PACKARD INTERFACE BUS (HP-IB)

ADDITIONAL EQUIPMENT INFORMATION

Accessories Supplied

Electrical Equipment Available

Mechanical Equipment Available

RF Power Measurements

Modulation Measurements

Additional Features

Extending Measurement Range

Programmability

Audio Circuitry

Amplitude Modulation

Exponential Modulation

Other Considerations

Rack Mounting

Packaging

Description

Front-Panel Features

Rear-Panel Features