HP 8731xx Service.pdf part of Agilent HP 8731xx Service HP 8731xx Service.pdf, Agilent HP 8731xx Service.pdf text manual preview

Text preview for : HP 8731xx Service.pdf part of Agilent HP 8731xx Service Agilent HP 8731xx Service.pdf

Back to : HP 8731xx Service.pdf | Home

Notice
Hewlett-Packard to Agilent Technologies Transition
This documentation supports a product that previously shipped under the Hewlett-
Packard company brand name. The brand name has now been changed to Agilent
Technologies. The two products are functionally identical, only our name has changed. The
document still includes references to Hewlett-Packard products, some of which have been
transitioned to Agilent Technologies.

Printed in USA March 2000
Contacting Agilent

By internet, phone, or fax, get assistance with all your test and measurement needs.
Table 1-1 Contacting Agilent
Online assistance: www.agilent.com/find/assist

United States Latin America Canada Europe
(tel) 1 800 452 4844 (tel) (305) 269 7500 (tel) 1 877 894 4414 (tel) (+31) 20 547 2323
(fax) (305) 269 7599 (fax) (905) 282-6495 (fax) (+31) 20 547 2390

New Zealand Japan Australia
(tel) 0 800 738 378 (tel) (+81) 426 56 7832 (tel) 1 800 629 485
(fax) (+64) 4 495 8950 (fax) (+81) 426 56 7840 (fax) (+61) 3 9210 5947

Asia Call Center Numbers

Country Phone Number Fax Number

Singapore 1-800-375-8100 (65) 836-0252

Malaysia 1-800-828-848 1-800-801664

Philippines (632) 8426802 (632) 8426809
1-800-16510170 (PLDT 1-800-16510288 (PLDT
Subscriber Only) Subscriber Only)

Thailand (088) 226-008 (outside Bangkok) (66) 1-661-3714
(662) 661-3999 (within Bangkok)

Hong Kong 800-930-871 (852) 2506 9233

Taiwan 0800-047-866 (886) 2 25456723

People's Republic 800-810-0189 (preferred) 10800-650-0121
of China 10800-650-0021

India 1-600-11-2929 000-800-650-1101
Service Guide
HP 83711A/12A and HP 83711B/12B
Synthesized CW Generators

SERIAL NUMBERS
This manual applies directly to instruments with serial number prex US3449 and above.

ABCDE
HP Part No. 83711-90134
Printed in USA July 1997 Supersedes April 1995
Notice.
The information contained in this document is subject to change without notice.
Hewlett-Packard makes no warranty of any kind with regard to this material, including
but not limited to, the implied warranties of merchantability and tness for a particular
purpose. Hewlett-Packard shall not be liable for errors contained herein or for incidental or
consequential damages in connection with the furnishing, performance, or use of this material.

Copyright Hewlett-Packard Company 1995, 1997
c
All Rights Reserved. Reproduction, adaptation, or translation without prior written permission
is prohibited, except as allowed under the copyright laws.
1400 Fountaingrove Parkway, Santa Rosa CA, 95403-1799, USA
Introduction
The HP 83711A/12A and HP 83711B/12B synthesized CW generators have dierent frequency
ranges. The HP 83711A/11B has a frequency range of 1 to 20 GHz, and the HP 83712A/12B has
a frequency range of 10 MHz to 20 GHz.
The service information for the HP 83711A/12A and HP 83711B/12B synthesized CW generators
comes in two manuals.
The HP 83711A/12A and HP 83711B/12B Synthesized CW Generators Service Guide provides
information needed to repair the synthesizer to the assembly level. The HP 83711A/12A,
HP 83711B/12B, HP 83731A/32A and HP 83731B/32B Synthesized Signal Generators
Component-Level Information manual provides component-level information for the repair of
individual instrument assemblies. The manual contains Component-Level Information Packets
(CLIPs) for selected assemblies. Each CLIP contains component-level schematics, a component
parts list, and illustrations for component location by reference designator.
Calibration information is in the HP 83711A/12A, HP 83711B/12B, HP 83731A/32A and
HP 83731B/32B Synthesized Signal Generators Calibration Guide. The calibration guide
contains the performance tests and adjustments for the synthesizer.
The service guide is what you receive when you order Option OBW, service documentation.

iii
In This Guide
The service guide includes the following chapters:
Chapter 1, \Troubleshooting," contains the troubleshooting information needed to isolate a
failed major assembly.
Chapter 2, \Block Diagrams," contains the block diagram that is to be used for the HP
83711A/12A and HP 83731B/32B.
Chapter 3, \Major Assembly and Cable Locations," contains drawings that show the major
assemblies and cable locations.
Chapter 4, \Parts List," contains information needed to order assemblies and parts for the
instrument.
Chapter 5, \Assembly Replacement," contains information needed to remove or replace a
major assembly.
Chapter 6, \Post-Repair Procedures," contains the procedures to be followed after a repair has
been made.
Chapter 7, \Error Messages," contains a list of all of the error messages that might be
generated during use of the instrument. Each entry in the list contains a sequence that can be
followed to recover from the error condition.
Chapter 8, \Options," contains a description of the various options available for use with the
synthesizers.
Chapter 9, \Contacting Hewlett-Packard," provides information on how to contact HP as well
as how to package and ship the instrument.
Chapter 10 \Legal and Regulatory Information," contains the information about manual
updates, operating environment, storage environment, ESD precautions, safety considerations,
etc.

Assumptions About You
The procedures in this guide assume that you have the tools and equipment to perform each
service task. To nd what tools and equipment belong to each service task, refer to the chapter
containing the task.

iv
Contents

1. Troubleshooting
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Prior to Beginning Troubleshooting . . . . . . . . . . . . . . . . . . . . . 1-1
The Service Position . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Power Supply Verication . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Warnings and Cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Before Applying Power . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
After-Service Safety Checks . . . . . . . . . . . . . . . . . . . . . . . . 1-3
ESD Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Recommended Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Service Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
TORX Screwdrivers . . . . . . . . . . . . . . . . . . . .
R . . . . . . . 1-4
Pozidrive Screwdrivers . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Major Assemblies, Parts, and Cable Locations . . . . . . . . . . . . . . . . 1-4
Test Point Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Service Aids on Printed Circuit Boards . . . . . . . . . . . . . . . . . . . 1-5
Other Service Documents . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Cleaning Intervals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Cleaning Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
12-Month Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
After Repair Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Main Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Microprocessor Assembly (A3) Troubleshooting . . . . . . . . . . . . . . . 1-9
ABUS Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
0.5 V/GHz Output Errors . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
LO Synthesizer and Reference Assembly (A6) Troubleshooting . . . . . . . . 1-11
Data Readback Errors . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
ABUS Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Oscillator Cold Error . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
LO Synthesizer and Reference Unlocked/Divide Voltage Errors . . . . . . . 1-13
YO Loop and Oset Synthesizer Assembly (A7) Troubleshooting . . . . . . . . 1-16
Data Readback Errors . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
ABUS Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Oset Synthesizer Incorrect Frequency/Unlocked Errors . . . . . . . . . . 1-18
YIG Driver Assembly (A9) Troubleshooting . . . . . . . . . . . . . . . . . 1-20
Data Readback Errors . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
ABUS Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
MSB Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
Low/High Band Voltage Errors . . . . . . . . . . . . . . . . . . . . . . 1-23
ALC Assembly (A10) Troubleshooting . . . . . . . . . . . . . . . . . . . . 1-25
Data Readback Errors . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
ABUS Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
DAC Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26
Contents-1
Integrator Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
Integrator Errors (Revision 10.01 and Above Only) . . . . . . . . . . . . . 1-27
Leveled Indicator Trip Point Errors . . . . . . . . . . . . . . . . . . . . 1-27
Leveled Indicator Trip Point Errors (Revision 10.01 and Above Only) . . . . 1-27
RF/Reference Detector Errors . . . . . . . . . . . . . . . . . . . . . . 1-27
Input/Output Switching Errors . . . . . . . . . . . . . . . . . . . . . . 1-29
Input/Output Switching Errors (Revision 10.01 and Above Only) . . . . . . 1-29
Track and Hold Errors . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29
Track and Hold Errors (Revision 10.01 and Above Only) . . . . . . . . . . 1-29
Output Module (A8A1) Troubleshooting . . . . . . . . . . . . . . . . . . . 1-30
Combiner/High Band/Low Band Errors . . . . . . . . . . . . . . . . . . 1-30
SLPFA (A8A3) Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . 1-31
Input/Output Bias Errors . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
YO Loop and Oset Synthesizer Assembly (A7) Troubleshooting . . . . . . . . 1-34
Sampler (A8T1) Troubleshooting . . . . . . . . . . . . . . . . . . . . . . 1-41
LO Unlocked Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-41
Oset Synthesizer Unlocked Errors . . . . . . . . . . . . . . . . . . . . 1-42
YO Loop Unlocked Errors . . . . . . . . . . . . . . . . . . . . . . . . 1-42
SLPFA (A8A3) Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . 1-50
Unleveled at Minimum Vernier Errors . . . . . . . . . . . . . . . . . . . 1-50
Unleveled at Maximum Vernier Errors . . . . . . . . . . . . . . . . . . 1-51
Divider and Modulation Assembly (A4) Troubleshooting . . . . . . . . . . . 1-52
Symptom Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . 1-56
Checking the Power Supply . . . . . . . . . . . . . . . . . . . . . . . . 1-57
Checking the Front Panel Display . . . . . . . . . . . . . . . . . . . . . . 1-57
Checking the Hewlett-Packard Interface Bus (HP-IB) . . . . . . . . . . . . . 1-58
Checking the Microprocessor . . . . . . . . . . . . . . . . . . . . . . . . 1-58
Checking the 10 MHz Output . . . . . . . . . . . . . . . . . . . . . . . . 1-59
Checking the 10 MHz Input . . . . . . . . . . . . . . . . . . . . . . . . . 1-59
Checking the 0.5V/GHz Output . . . . . . . . . . . . . . . . . . . . . . . 1-60
Checking the Output Path . . . . . . . . . . . . . . . . . . . . . . . . . 1-60
To Troubleshoot the Option 1E1 Output Path . . . . . . . . . . . . . . . 1-60
To Troubleshoot the Non-Option 1E1 Output Path . . . . . . . . . . . . . 1-61
Checking External ALC . . . . . . . . . . . . . . . . . . . . . . . . . . 1-62
2. Block Diagrams
3. Major Assembly and Cable Locations
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
4. Parts List
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Replaceable Parts Table Format . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Illustrated Parts Breakdowns . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Optional Congurations . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Parts List Backdating . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Parts Identication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Other Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Exchange Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

Contents-2
5. Assembly Replacement
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Assembly and Part Locations . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Major Assembly and Cable Locations . . . . . . . . . . . . . . . . . . . . 5-7
Service Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Special Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Fasteners (Screws and Nuts) . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Cable and Connector Identication . . . . . . . . . . . . . . . . . . . . . 5-9
Semi-Rigid Coaxial Cables . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
Flexible Coaxial Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
SMC Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
SMA Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
SMB Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
Multi-wire Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
Synthesizer Covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
To Remove the Top Cover . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
To Remove the Bottom Cover . . . . . . . . . . . . . . . . . . . . . . . . 5-15
Power Supply (A11) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-17
To Disconnect the Power Supply Cables . . . . . . . . . . . . . . . . . . . 5-17
To Remove the Power Supply . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19
Fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
To Remove (and Replace) the Fuse . . . . . . . . . . . . . . . . . . . . . 5-20
Fan Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-21
To Disconnect the Fan Cable . . . . . . . . . . . . . . . . . . . . . . . . 5-21
To Remove the Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
Divider and Modulation Board Assembly (A4) . . . . . . . . . . . . . . . . . 5-23
To Access the Service Position . . . . . . . . . . . . . . . . . . . . . . . 5-23
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
Microprocessor Board Assembly (A3) . . . . . . . . . . . . . . . . . . . . . 5-26
To Access the Service Position . . . . . . . . . . . . . . . . . . . . . . . 5-26
To Disconnect the Cables . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
To Remove the Microprocessor Assembly . . . . . . . . . . . . . . . . . . 5-27
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-27
Battery (A3BT1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
To Access the Service Position . . . . . . . . . . . . . . . . . . . . . . . 5-29
To Remove the Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-30
Crystal Oscillator (Option 1E5) . . . . . . . . . . . . . . . . . . . . . . . . 5-31
To Disconnect the Oscillator Cables . . . . . . . . . . . . . . . . . . . . . 5-31
To Remove the Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
ALC Board Assembly (A10) . . . . . . . . . . . . . . . . . . . . . . . . . . 5-33
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-33
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-33
YIG Driver Board Assembly (A9) . . . . . . . . . . . . . . . . . . . . . . . 5-35
To Access the Service Position . . . . . . . . . . . . . . . . . . . . . . . 5-35
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-36
YO (YIG Oscillator) Loop/Oset Synthesizer Board Assembly (A7) . . . . . . . . 5-38
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
Contents-3
LO (Local Oscillator) Synthesizer/ Reference Board Assembly (A6) . . . . . . . 5-40
To Access the Service Position . . . . . . . . . . . . . . . . . . . . . . . 5-40
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-41
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-42
Step Attenuator, A8AT1 (Option 1E1) . . . . . . . . . . . . . . . . . . . . . 5-44
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-44
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-44
Sampler Microcircuit, A8T1 . . . . . . . . . . . . . . . . . . . . . . . . . . 5-46
To Remove the Subassembly . . . . . . . . . . . . . . . . . . . . . . . . 5-46
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-48
YIG Oscillator(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-49
To Remove the Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-49
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-50
YIG Driver Cable and Temperature Transducer . . . . . . . . . . . . . . . . 5-53
To Remove the Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-53
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-54
Output Module, SLPFA Module, and Coupler Detector . . . . . . . . . . . . . 5-55
To Remove the Subassemblies . . . . . . . . . . . . . . . . . . . . . . . 5-55
To Remove the Coupler Detector Subassembly . . . . . . . . . . . . . . . . 5-56
To Remove the Output Module and the SLPFA Module Subassemblies . . . . . 5-58
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-58
RF Output Connector/Adapter, CP1 . . . . . . . . . . . . . . . . . . . . . . 5-60
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-60
To Reassemble the Instrument . . . . . . . . . . . . . . . . . . . . . . . 5-62
HP-IB Cable Interface Replacement . . . . . . . . . . . . . . . . . . . . . . 5-64
To Remove the Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 5-64
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-65
Front Panel (A1, A2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-66
To Remove the Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . 5-66
To Remove the ALC Cable/Connector . . . . . . . . . . . . . . . . . . . . 5-66
To Remove the Front Frame . . . . . . . . . . . . . . . . . . . . . . . . 5-68
To Remove the Display (A2) . . . . . . . . . . . . . . . . . . . . . . . . 5-69
To Remove the Keyboard (A1) . . . . . . . . . . . . . . . . . . . . . . . 5-69
To Remove the Dress Panel . . . . . . . . . . . . . . . . . . . . . . . . . 5-69
Reassembly Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-71
6. Post-Repair Procedures
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
7. Error Messages
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Error Messages List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
8. Options
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Electrical Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Option 1E1 - Add Output Step Attenuator . . . . . . . . . . . . . . . . . . 8-2
Option 1E5 - Add High Stability Timebase . . . . . . . . . . . . . . . . . . 8-2
Option 1E8 - 1 Hz Frequency Resolution . . . . . . . . . . . . . . . . . . 8-2
Option 1E9 - 3.5 mm RF Output Connector . . . . . . . . . . . . . . . . . 8-2
Mechanical Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Option 1CM - Rack Mount Kit . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Option 1CP - Rack Mount and Handle Kit . . . . . . . . . . . . . . . . . . 8-3
Option 1CR - Rack Slide Kit . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Contents-4
Warranty Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Option W30 - Two Additional Years Return-to-HP Service . . . . . . . . . . . 8-3
Option W32 - Three Year Return to HP Calibration Service . . . . . . . . . . 8-3
Documentation Options . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Option OB0 - Delete Operating Documentation . . . . . . . . . . . . . . . . 8-4
Option OB1 - Extra Operating Documentation . . . . . . . . . . . . . . . . 8-4
Option OBV - Component-Level Information Packet (CLIP) . . . . . . . . . . 8-4
Option OBW - Service Documentation . . . . . . . . . . . . . . . . . . . . 8-4
Option OBX - Component-Level Information Packet (CLIP)/Service
Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
9. Contacting Hewlett-Packard
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Returning Instruments for Service . . . . . . . . . . . . . . . . . . . . . . 9-2
Service Tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Original Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Other Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Sales and Service Oces . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
10. Legal and Regulatory Information
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1
Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2
Before Applying Power . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2
Safety Earth Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2
Safety Symbols and Notes . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
Electrostatic Discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
PC Board Assemblies and Electronic Components . . . . . . . . . . . . . . 10-4
Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
ESD Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Certication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Limitation of Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Exclusive Remedies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6
Index

Contents-5
Figures

2. HP 83731A/B, HP 83732A/B Overall Block Diagram Foldout . . . . . . . . . 2-3
3-1. Major Assemblies { Top View . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3-2. Major Assemblies { Bottom View . . . . . . . . . . . . . . . . . . . . . . 3-3
3-3. Cable Assemblies { Top View . . . . . . . . . . . . . . . . . . . . . . . . 3-4
3-4. Cable Assemblies { Bottom View . . . . . . . . . . . . . . . . . . . . . . 3-5
4-1. Major Assemblies Location Diagram (Top View) . . . . . . . . . . . . . . . 4-8
4-2. Major Assemblies Location Diagram (Bottom View) . . . . . . . . . . . . . . 4-10
4-3. Cable Assemblies Location Diagram (Top View) . . . . . . . . . . . . . . . 4-12
4-4. Cable Assemblies Location Diagram (Bottom View) . . . . . . . . . . . . . . 4-14
4-5. Figures Orientation Diagram, Top View . . . . . . . . . . . . . . . . . . . 4-15
4-6. Figures Orientation Diagram, Bottom View . . . . . . . . . . . . . . . . . 4-16
4-7. Top and Bottom Cover Illustrated Parts Breakdown . . . . . . . . . . . . . 4-18
4-8. Front Panel Illustrated Parts Breakdown . . . . . . . . . . . . . . . . . . 4-20
4-9. Front Frame and Display/Keyboard Illustrated Parts Breakdown . . . . . . . 4-22
4-10. Front Dress Panel Illustrated Parts Breakdown . . . . . . . . . . . . . . . . 4-24
4-11. Top Side Circuit Board Illustrated Parts Breakdown . . . . . . . . . . . . . 4-26
4-12. Fan, Power Supply, and Rear Panel Connector Illustrated Parts Breakdown . . 4-28
4-13. YIG, Crystal Oscillator, and Sampler Microcircuit Illustrated Parts Breakdown . 4-30
4-14. Attenuator, Bottom Side Circuit Board, and Rails Illustrated Parts Breakdown . 4-32
4-15. Microwave Output and SLPFA Illustrated Parts Breakdown . . . . . . . . . . 4-34
4-16. Microwave Deck Illustrated Parts Breakdown . . . . . . . . . . . . . . . . 4-36
5-1. Location of Major Assemblies{Top View . . . . . . . . . . . . . . . . . . . 5-3
5-2. Location of Major Assemblies{Bottom View . . . . . . . . . . . . . . . . . 5-4
5-3. Cable Locations{Top View . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
5-4. Cable Locations{Bottom View . . . . . . . . . . . . . . . . . . . . . . . 5-6
5-5. Top or Bottom Cover Removal . . . . . . . . . . . . . . . . . . . . . . . 5-12
5-6. Service Position{Top Cover Removed . . . . . . . . . . . . . . . . . . . . 5-14
5-7. Service Position{Bottom Cover Removed . . . . . . . . . . . . . . . . . . 5-16
5-8. Power Supply Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
5-9. Power Supply Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19
5-10. Line Fuse Removal and Replacement . . . . . . . . . . . . . . . . . . . . 5-20
5-11. Fan Cable Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-21
5-12. Fan Assembly Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22
5-13. Divider and Modulation Board Assembly Removal . . . . . . . . . . . . . . 5-25
5-14. Microprocessor Board Assembly Cable Location . . . . . . . . . . . . . . . 5-27
5-15. Microprocessor Board Assembly Removal . . . . . . . . . . . . . . . . . . 5-28
5-16. Microprocessor Board Battery Removal . . . . . . . . . . . . . . . . . . . 5-30
5-17. Crystal Oscillator Cables . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
5-18. Crystal Oscillator Removal . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
5-19. ALC Board Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-34
5-20. YIG Driver Board Service Position . . . . . . . . . . . . . . . . . . . . . 5-35
5-21. YIG Driver Board Removal . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
5-22. YO Loop and Oset Synthesizer Board Removal . . . . . . . . . . . . . . . 5-39
5-23. LO Synthesizer and Reference Board Service Position . . . . . . . . . . . . 5-41
5-24. LO Synthesizer and Reference Board Removal . . . . . . . . . . . . . . . . 5-43
5-25. Step Attenuator Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-45
Contents-6
5-26. Sampler Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-46
5-27. YIG Oscillator Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-51
5-28. Output Module, SLPFA Module, and Coupler Detector Removal . . . . . . . . 5-56
5-29. Output Module, SLPFA Module, and Coupler Detector Separation . . . . . . . 5-57
5-30. RF Output Connector Removal{Standard . . . . . . . . . . . . . . . . . . 5-61
5-31. RF Output Connector Removal{Option 1E1 . . . . . . . . . . . . . . . . . 5-62
5-32. HP-IB Cable Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-64
5-33. Front Panel and BNC Connector Removal . . . . . . . . . . . . . . . . . . 5-67
5-34. Front Frame Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-68
5-35. Display and Keyboard Removal . . . . . . . . . . . . . . . . . . . . . . . 5-70
5-36. Dress Panel Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-71
10-1. Static-Safe Workstation . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4

Contents-7
Tables

1-1. Recommended Test Equipment . . . . . . . . . . . . . . . . . . . . . . . 1-6
1-2. YIG Continuity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-39
1-5. A2J1 Voltages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-57
4-1. Part Numbers for Exchange Assemblies . . . . . . . . . . . . . . . . . . . 4-5
4-2. Reference Designations . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
4-3. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
4-4. Multipliers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
4-5. Major Assemblies, Top View . . . . . . . . . . . . . . . . . . . . . . . . 4-8
4-6. Major Assemblies, Bottom View . . . . . . . . . . . . . . . . . . . . . . . 4-9
4-7. Cable Assemblies, Top View . . . . . . . . . . . . . . . . . . . . . . . . 4-11
4-8. Cable Assemblies, Bottom View . . . . . . . . . . . . . . . . . . . . . . . 4-13
4-9. Illustrated Replaceable Parts . . . . . . . . . . . . . . . . . . . . . . . . 4-17
5-1. Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
5-2. Fastener Torque Values . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
9-1. Hewlett-Packard Sales and Service Oces . . . . . . . . . . . . . . . . . . 9-4

Contents-8
1
Troubleshooting

Introduction
This chapter contains troubleshooting procedures that isolate problems to the assembly level.
Always begin troubleshooting by following the procedure titled \Main Troubleshooting." At the
start of the main troubleshooting procedure, run the synthesizer internal self test. Depending
on the error messages returned by the self test routine, follow the procedures that verify the
detected error condition. These procedures are self-contained and also verify the inputs that
can have an eect on the detected error. If the self test does not detect any errors, a set of
procedures at the end of this chapter veries circuits that are not checked with the self tests.
These procedures are referenced by symptom.

Prior to Beginning Troubleshooting
The following paragraphs present information that must be understood prior to beginning
troubleshooting. This information is important to know regardless of the path taken by the
troubleshooting.
The Service Position
To access many of the measurement points on an assembly, the assembly must be installed
in the service position. Refer to procedures in Chapter 5, \Assembly Replacement," for
instructions on how to install a given assembly in the service position. These procedures are
grouped by assembly. The individual troubleshooting procedures note when it is necessary to
install an assembly in the service position.
Power Supply Verication
Occasionally, an apparent failure on an assembly might be caused by a voltage that is out of
specication on the power supply assembly.
On the end of the power supply facing the front of the synthesizer, there are seven green
LEDs. When an LED is on, that supply is operating within its specied tolerance. If the LED is
o, the supply has failed or the supply is being loaded down by one of the assemblies.

Troubleshooting 1-1
Troubleshooting
Safety Considerations
Warnings and Cautions
Pay attention to WARNINGS and CAUTIONS. They must be followed for your protection and to
avoid damage to the equipment.

Before Applying Power
Caution Verify that the instrument is set to match the available line (mains) voltage
and that the correct fuse is installed. An uninterrupted safety earth ground
must be provided from the main power source to the instrument input wiring
terminals or power cable.

Warning Maintenance described herein is performed with power supplied to the
instrument and with protective covers removed. Such maintenance
should be performed only by service-trained personnel who are aware
of the hazards involved (for example, re and electrical shock). Where
maintenance can be performed without power supplied, the power
should be removed.
Any interruption of the protective (grounding) conductor (inside or
outside the instrument) or disconnecting the protective earth terminal
will cause a potential shock hazard that could result in personal injury.
(Grounding one conductor of a two conductor outlet is not sucient
protection.) In addition, verify that a common ground exists between
this instrument and the test equipment prior to energizing either unit.
Whenever it is likely that the protection has been impaired, the
instrument must be made inoperative and be secured against any
unintended operation.
If this instrument is to be energized via an autotransformer (for voltage
reduction) make sure that the common terminal is connected to neutral
(that is, the grounded side of the mains supply).
Servicing instructions are for use by service-trained personnel only. To
avoid dangerous electric shock, do not perform any servicing unless
qualied to do so.
Energy available at many points may, if contacted, result in personal
injury.
Capacitors inside the instrument may still be charged even if the
instrument has been disconnected from its source of supply.
For continued protection against re hazard, replace the line fuse(s)
only with 250 V fuse(s) of the same current rating and type (for example
normal blow, time delay, etc.). Do not use repaired fuses or short
circuited fuse holders.

1-2 Troubleshooting
Troubleshooting
Caution Unplug the instrument before disconnecting or removing any boards. Some
boards contain devices that can be damaged if the board is removed when
the power is on.
There are several components including MOS and CMOS devices that can
be damaged by electrostatic discharge. Use conductive foam and grounding
straps when servicing sensitive components. Carefully unplug ICs in high-grip
sockets.

After-Service Safety Checks
Visually inspect the interior of the instrument for any signs of abnormal internally generated
heat, such as discolored printed circuit boards or components, damaged insulation, or evidence
of arcing. Determine and remedy the cause of any such condition.
Using a suitable ohmmeter, check the resistance from the instrument enclosure to the ground
pin on the power cord plug. The reading must be less than one ohm. Flex the power cable
while making this measurement to determine whether intermittent discontinuities exist.
Check any indicated rear-panel ground terminals that are marked, using the above procedures.
Check the resistance from the instrument enclosure to line and neutral (tied together) with
the on/o switch in the ON ( j ) position and the power source disconnected. The minimum
acceptable resistance is two megohms. Replace any component that results in a failure.
Check the line fuse to verify that a correctly rated fuse is installed.

ESD Precautions
There are several components including MOS, CMOS, and microwave devices that can be
damaged by electrostatic discharge (ESD). A sensitive assembly should be stored in an antistatic
container whenever it is not installed. Use a static free work area and a properly grounded
wrist strap. Refer to Chapter 10, \Legal and Regulatory Information," for more detailed
information.

Recommended Test Equipment
Test equipment and accessories required to maintain the instrument are listed in Table 1-1,
\Recommended Test Equipment." Equipment other than that listed may be used if it meets the
critical specications listed in the table.

Troubleshooting 1-3
Troubleshooting
Service Accessories
TORX Screwdrivers
R
Most of the screws in the synthesizer are TORX screws. Remove these screws with a TORX
R R
screwdriver. The part number of the #10 TORX screwdriver is HP 8710-1623. The part
R
number of the #15 TORX screwdriver is HP 8710-1622. The part number of the #25 TORX
R R
screwdriver is HP 8710-1617.

Pozidrive Screwdrivers
Some screws in the instrument appear to be Phillips type, but are not. To avoid damage to
the screw head slots, Pozidrive screwdrivers should be used. The part number of the No. 1
Pozidrive is HP 8710-0899. The part number of the No. 2 Pozidrive is HP 8710-0900.

Hardware
The instrument has a mixture of Unied National (inch) and metric screws. The metric screws
are dened in Industrial Fasteners publication (IFI 500). Do not use a metric screw in a Unied
National nut, or a metric nut with a Unied National screw because thread damage will occur.

Major Assemblies, Parts, and Cable Locations
The locations of individual components mounted on printed circuit boards are available
for selected instrument assemblies. The information for these assemblies is provided in
the accompanying HP 83711A/12A, HP 83711B/12B, HP 83731A/32A and HP 83731B/32B
Synthesized Signal Generators Component-Level Information manual. Each tabbed section in
the Component-Level Information manual contains the parts list, component-location diagram,
and schematic for that specied assembly.
The part reference designation is the assembly designation plus the part designation. For
example, A6R9 is R9 on the A6 assembly. For specic component descriptions and ordering
information, see the parts list in the Component-Level Information Packet for that board.
Chassis and frame parts, as well as mechanical parts and cables (W), are identied in illustrated
parts breakdowns in Chapter 4.
The procedures in this chapter reference cables and assemblies by their reference designator.
Figures 3-1 to 3-4 show where the assemblies and cables are located in the synthesizer. The
gures are located in Chapter 3.

Test Point Locations
Most test points are indicated on the actual circuit-board assemblies. Test and measurement
points called out in the troubleshooting procedures are shown on the component-location
diagrams in the Component-Level Information manual.

1-4 Troubleshooting
Troubleshooting
Service Aids on Printed Circuit Boards
Service aids on printed circuit boards include test points, indicator lights, some reference
designations, and assembly part numbers.

Other Service Documents
Service notes and other service literature are available through Hewlett-Packard. For further
information, contact your nearest Hewlett-Packard oce.

Cleaning
Cleaning Intervals
Warning Before cleaning, make sure the instrument is disconnected from the power
source. This is to eliminate the possibility of electrical shock.

Caution In procedures that call for a vacuum cleaner to remove dust, do not use a
blower or compressed air. Doing so will cause the dust to be transferred
throughout the instrument.

Hewlett-Packard recommends a 12-month interval between cleaning for some parts of the
instrument. But, cleaning intervals are mostly dependent upon where the instrument is used.
The instrument should be cleaned more often if it is in a dusty or very humid area.

Cleaning Solution
Hewlett-Packard recommends using either of two cleaning solutions on printed circuit (PC)
board edge connectors. For best cleaning results, we recommend an ammonium hydroxide
solution (NH4OH, 29.5% NH3 by weight). But, a concentrated solution of ammonia requires
the use of gloves, eye goggles, and proper ventilation. The second recommendation is an 80:20
solution of isopropyl alcohol and water (IPA/H2O). This should serve as a satisfactory cleaner if
you do not want to use ammonium hydroxide.

12-Month Cleaning
At 12-month intervals the instrument covers should be removed to gain access to the cooling
fan.
Wipe the instrument fan with a clean cloth or tissue, or vacuum for dust.
Remove each printed circuit board, and clean the component side of the board with
compressed air. Set the air pressure to 20 psi maximum. To remove the boards, refer to
Chapter 5, \Assembly Replacement." Return the boards to the instrument.
After cleaning, reinstall the covers.

Troubleshooting 1-5
Troubleshooting
After Repair Calibration
Once the synthesizer is repaired, it may be necessary to calibrate the instrument. Refer to
the HP 83711A/12A, HP 83711B/12B, HP 83731A/32A and HP 83731B/32B Synthesized Signal
Generators Calibration Guide to determine when it is necessary to use the performance tests
and adjustments. Chapter 6, \Post-Repair Procedures," should be referred to as well.
The following table contains the list of recommended test equipment that can be used for
troubleshooting.
Table 1-1. Recommended Test Equipment
Equipment Critical Specications Recommended
Model
Frequency Frequency Range: 1 to 20 GHz HP 5343A
Counter
Function Frequency: 100 kHz HP 3325A
Generator Amplitude: 0 to 5 Vp-p
Multimeter No substitute HP 3458A
Oscilloscope HP 54111D
Power Meter Accuracy: 0.02 dB HP 437B
Frequency range: 100 MHz
Power Sensor Power Meter compatible HP 8482A
Power Supply Range: 010 V to +10 V HP 6235A
Signal Generator Frequency Range: 1 MHz to 25 MHz HP 8663A
Amplitude: 010 dBm to +10 dBm
Spectrum HP 8566B
Analyzer

1-6 Troubleshooting
Troubleshooting
Main Troubleshooting
1. Run the instrument self test.
a. Press the 4 5 key.
SPCL

b. Press 4 5 on the numeric keypad.
5

c. Terminate the entry by pressing 4 5 (ENTER)
Hz

When 4 5, 4 5, 4 5 (ENTER) is pressed, the text SELF TEST?, PRESS ENTER will be shown
SPCL 5 Hz

on the synthesizer display. Pressing 4 5 (ENTER) will then cause all self test segments to be
Hz

run. Pressing any key other than 4 5 will cause the self test not to run.
Hz

As the self test is running, the messages PRESETTING INSTRUMENT and SELF TESTING! will
appear on the display. If the self test does not detect a failure, the message Self Test
passed will appear on the display.
If the self test does detect a failure, the display will show numbers in the form \X = Y"
momentarily, and then the self test will stop. At this point, the MSG LED will be lit. Press
the 4 5 key, and a message will be displayed in the form of \40XX". \40" represents
MSG

the self test, and \XX" represents the failed group. Rerun the self test. As you monitor
the display, be prepared to write down the error code \X = Y", as this will be used for
troubleshooting purposes. \X" references a test group. Each test within a test group is given
a unique number. \Y" is the hexadecimal sum of all test numbers within a test group that
failed. The self test aborts upon completion of a test group that reports test failures.
If no failure is detected, go to the procedure entitled \Symptom Troubleshooting" to
continue. If a failure is detected, continue with the next step.
2. Decode the numerical self test result to determine the component error messages indicated
by the result.
Note It is not necessary to decode the error messages if doing so provides no further
information. For example, if multiple errors in error group 8 are decoded, the
resultant error text for all error numbers would be identical (\Data Readback
from LO Assembly").

a. Search through the tables titled \Error Groups Covered" that are at the beginning of
the procedures on the following pages to nd the rst number of the error display
(\X" in \X = Y").
For example, if 22 = fc is displayed as the result of running the self test, search through
the tables in the following procedures and nd the error messages that begin with 22.
b. If the second number of the error display matches any of the error numbers in the error
lists included in the procedure, that is the only error message reported. If the second
number does not match, it must be decoded.
c. To decode the error display, nd the number in the list of error messages that is the
largest number that can be subtracted from the displayed number and subtract it. For
example, if 22 = fc is displayed, subtract 80 from fc (80 is the largest hexadecimal
number from the list of \22 = Y" errors that can be subtracted from fc). One of the
errors is 22 = 80 and the result of the subtraction leaves 7c.
d. Continue this subtraction process until the result is zero. For example, the result 22 = fc,
when fully decoded, will yield 22 = 80, 22 = 40, 22 = 20, 22 = 10, 22 = 8, and 22 = 4.
If the message returned was 36 = 550, 550 would have to be decoded in order to
determine the failure conditions. To decode 36 = 550, review the list of codes for table
36. Find the largest number from the list that can be subtracted from 550. In table 36,
this number would be 400. 36 = 400 is one of the tests that failed. Take the remainder
from the rst subtraction and once again subtract the largest number from the list that is

Troubleshooting 1-7
Troubleshooting
smaller than the remainder. Continue with this process until the remainder is 0 in order
to determine each test that failed.
550 0 400 = 150. Unleveled at 8.0 GHz.
150 0 100 = 50. Unleveled at 4.8 GHz.
50 0 40 = 10. Unleveled at 2.75 GHz.
10 0 10 = 0. Unleveled at 1.65 GHz.
These codes indicate that this instrument failed 4 tests in table 36. It was unleveled at
1.65, 2.75, 4.8, and 8.0 GHz.
3. Carry out the procedure that follows the applicable list of error messages and continue
troubleshooting. Begin at the procedure appropriate for the messages reported.

1-8 Troubleshooting
Troubleshooting
Microprocessor Assembly (A3) Troubleshooting
The following error groups pertain to the microprocessor assembly.
Error Group Description
4=Y ABUS Errors
6=Y 0.5 V/GHz Output Errors
7=Y

Note Prior to replacing an assembly or module, verify that the power supply voltages
are within specication at the power connection to the assembly or module.

ABUS Errors
Error Group Description
4=1 615 V on CPU Assy
4=2 Digital +5 V on the CPU Assy
4=4 Analog +5 V on the CPU Assy
4=8 Digital Ground on the CPU Assy

1. Measure the suspected voltage at the pin number of J1 on the microprocessor assembly (A3)
shown in the following table. Do not disconnect W8 from J1 when making the measurement
(connect the voltmeter ground lead to A3TP4).
Suspect J1 Pin Voltage
Voltage Number
+15 V 4 +15 V 61 V
Digital Ground 13 0 V 60.1 V
+5.2 V digital 6 +4.8 V to +5.4 V
015 V 12 015 V 61 V
+5 V analog 8 +5 V 60.6 V

2. If the voltage is present and within tolerance at J1, replace the microprocessor assembly. If
one or more voltages are failing, continue with the next step.
3. On the end of the power supply facing the front of the synthesizer, there are seven green
LEDs. When the LEDs are on, the supplies are operating within their specied tolerance. If
the LED for the failing voltage is on, replace W8. If the LED is o, continue with the next
step.
4. One of the assemblies is loading down the power supply. Disconnect W8 from each assembly
one assembly at a time to locate the failing assembly.

Troubleshooting 1-9
Troubleshooting
0.5 V/GHz Output Errors
Error Group Description
6=2 Failure at 1.0 GHz
6=8 Failure at 3.0 GHz
6 = 20 Failure at 6.0 GHz
6 = 80 Failure at 9.0 GHz
6 = 200 Failure at 12.0 GHz
6 = 800 Failure at 15.0 GHz
6 = 2000 Failure at 18.0 GHz
6 = 8000 Failure at 20.0 GHz
7=2 Failure at 0.01 GHz

1. Connect a voltmeter to pin 5 of J1 on the microprocessor assembly (A3) (connect the
voltmeter ground lead to A3TP4).
2. Set the synthesizer output frequency to the frequency specied in the error message (if
more than one frequency point failed, set the output frequency to the lowest frequency
specied).
3. Verify that the voltage at J1 is within the tolerance shown in the following table.
Frequency Voltage
1.0 GHz 0.5 V 60.50 V
3.0 GHz 1.5 V 60.50 V
6.0 GHz 3.0 V 60.50 V
9.0 GHz 4.5 V 60.50 V
12.0 GHz 6.0 V 60.50 V
15.0 GHz 7.5 V 60.50 V
18.0 GHz 9.0 V 60.50 V
20.0 GHz 10 V 60.50 V
0.01 GHz 5 mV 60.5 V

If the voltage is within tolerance, check the continuity of W8 between J1 pin 5 and the
0.5V/GHz output connector and replace it if necessary. If the voltage is out of tolerance,
continue with the next step.
4. Perform the adjustment procedure \0.5 V/GHz Output Adjustment" in the Calibration Guide.
If the 0.5 V/GHz output cannot be adjusted using the procedure or the self test still fails,
replace the microprocessor assembly. If it can be adjusted successfully, rerun the self test to
ensure that the 0.5 V/GHz output is functioning at all tested frequencies.

1-10 Troubleshooting
Troubleshooting
LO Synthesizer and Reference Assembly (A6) Troubleshooting
The following error groups pertain to the LO synthesizer