Performance Tests and

Adjustments Manual

HP 8568B Spectrum Analyzer

HEWLETT

PACKARD

HP Part No. 08568-90118

Printed in USA September 1993

@Copyright Hewlett-Packard Company 1993

All Rights Reserved. Reproduction, adaptation, or translation without prior written permission is prohibited, except as allowed under the copyright laws.

1212 Valley House Drive, Rohnert Park, CA 94928-4999, USA

Certification

Warranty

Hewlett-Packard Company certifies that this product met its published specifications at the time of shipment from the factory. Hewlett-Packard further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology, to the extent allowed by the Institute???s calibration facility, and to the calibration facilities of other International Standards Organization members.

This Hewlett-Packard instrument product is warranted against defects in material and workmanship for a period 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 to be defective.

For warranty service or repair, this product must be returned to a service facility designated by Hewlett-Packard. Buyer shall prepay shipping charges to Hewlett-Packard and Hewlett-Packard shall pay shipping charges to return the product to Buyer. However, Buyer shall pay all shipping charges, duties, and taxes for products returned to Hewlett-Packard from another country.

Hewlett-Packard warrants that its software and firmware designated by Hewlett-Packard for use with an instrument will execute

its programming instructions when properly installed on that instrument. Hewlett-Packard does not warrant that the operation of the instrument, or software, or firmware will be uninterrupted or error-free.

LIMITATION OF WARRANTY

The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by Buyer, Buyer-supplied software or interfacing, unauthorized modification or misuse, operation outside of the environmental specifications for the product, or improper site preparation or maintenance.

NO OTHER WARRANTY IS EXPRESSED OR IMPLIED.

HEWLETT-PACKARD SPECIFICALLY DISCLAIMS THE IMPLIED

WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

PARTICULAR PURPOSE.

EXCLUSIVE REMEDIES

THE REMEDIES PROVIDED HEREIN ARE BUYER???S SOLE AND

EXCLUSIVE REMEDIES. HEWLETT-PACKARD SHALL NOT BE

LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR

CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT,

TORT, OR ANY OTHER LEGAL THEORY.

. . .

III

Assistance

Product maintenance agreements and other customer assistance agreements are available for Hewlett-Rwkard products.

Fbr any assistance, contact your nearest Hewlett-Packard Sales and Service OJke.

Safety Symbols

The following safety symbols are used throughout this manual. Familiarize yourself with each of the symbols and its meaning before operating this instrument.

Caution The caution sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in damage to or destruction of the instrument. Do not proceed beyond a caution sign until the indicated conditions are fully understood and met.

Warning The warning sign denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in injury or loss of life. Do not proceed beyond a warning sign until the indicated conditions are fully understood and met.

General Safety

Considerations

Warning Before this instrument is switched on, make sure it has been properly grounded through the protective conductor of the ac power cable to a socket outlet provided with protective earth contact.

Any interruption of the protective (grounding) conductor, inside or outside the instrument, or disconnection of the protective earth terminal can result in personal injury.

Warning There are many points in the instrument which can, if contacted, cause personal injury. Be extremely careful.

Any adjustments or service procedures that require operation of the instrument with protective covers removed should be performed only by trained service personnel.

Caution Before this instrument is switched on, make sure its primary power circuitry has been adapted to the voltage of the ac power source.

Failure to set the ac power input to the correct voltage could cause damage to the instrument when the ac power cable is plugged in.

V

HP 8568B

Spectrum Analyzer

Documentation

Outline

HP 8568B Installation

and Verification

Manual

HP 8568B Operating

and Programming

Manual

HP 8568B

Performance Tests and

Adjustments Manual

Included with the HP Model 8568B Spectrum Analyzer are three manuals: the Installation and Verification Manual, the Operating and Programming Manual, and the Performance Tests and Adjustments Manual.

General information, installation, specifications, characteristics, and operation verification.

Manual and remote operation, including complete syntax and command description. Accompanying this manual is the separate, pocket-sized Quick Reference Guide.

Electrical performance tests and adjustment procedures.

HP 85680B RF Section RF Section service information.

Troubleshooting and

Repair Manual

HP 85662A IF-Display IF-Display Section service information.

Section

Troubleshooting and

Repair Manual

vi

Contents

4.Resolution Bandwidth Accuracy Test . . . . . . 2-13

5.Resolution Bandwidth Selectivity Test . . . . . . 2-15

6.Resolution Bandwidth Switching Uncertainty Test 2-18

7.Input Attenuator Switching Uncertainty Test . . 2-20

8.Frequency Response Test . . . . . . . . . . . . 2-22

9.RF Gain Uncertainty Test . . . . . . . . . . . . 2-31

10.IF Gain Uncertainty Test . . . . . . . . . . . 2-33

11.Log Scale Switching Uncertainty Test . . . . . 2-39

12.Amplitude Fidelity Test . . . . . . . . . . . . 2-41

13.Average Noise Level Test . . . . . . . . . . . 2-45

14.Residual Responses Test . . . . . . . . . . . . 2-47

15.Spurious Responses Test . . . . . . . . . . . . 2-49

16.Residual FM Test . . . . . . . . . . . . . . . 2-56

17.Line-Related Sidebands Tests . . . . . . . . . 2-60

18.Calibrator Amplitude Accuracy Test . . . . . . 2-62

19.Fast Sweep Time Accuracy Test (~20 ms) . . . . 2-63

20.1st LO Output Amplitude Test . . . . . . . . . 2-66

21.Frequency Reference Error Test . . . . . . . . 2-67 ???Ihble 2-19. Performance Test Record . . . . . . . . . . 2-69 Test 1. Center Frequency Readout Accuracy Test . . . 2-70 Test 2. Frequency Span Accuracy Test . . . . . . . . 2-71

Test 3. Sweep Time Accuracy . . . . . . . . . . . . 2-72 Test 4. Resolution Bandwidth Accuracy . . . . . . . 2-73 Test 5. Resolution Bandwidth Selectivity . . . . . . . 2-74 Test 6. Resolution Bandwidth Switching Uncertainty

Test . . . . . . . . . . . . . . . . . . . . . . 2-75 Test 7. Input Attenuator Switching Uncertainty Test . 2-76 Test 8. Frequency Response Test . . . . . . . . . . 2-77 Test 9. RF Gain Uncertainty Test . . . . . . . . . . 2-78 Test 10. IF Gain Uncertainty Test . . . . . . . . . . 2-79

C o n t e n t s - l

Test 11. Log Scale Switching Uncertainty Test . . . . 2-82 Test 12. Amplitude Fidelity Test . . . . . . . . . . . 2-83 Test 13. Average Noise Level Test . . . . . . . . . . 2-84 Test 14. Residual Responses Test . . . . . . . . . . . 2-85 Test 15. Spurious Responses Test . . . . . . . . . . 2-86 Test 16. Residual FM Test . . . . . . . . . . . . . . 2-87 Test 17. Line-Related Sidebands Test . . . . . . . . . 2-88 Test 18. Calibrator Amplitude Accuracy Test . . . . . 2-89 Test 19. Fast Sweep Time Accuracy Test (~20 ms) . . 2-90 Test 20. 1st LO Output Amplitude Test . . . . . . . . 2-91 Test 21. Frequency Reference Error Test . . . . . . . 2-92

3.Adjustments

1.Low-Voltage Power Supply Adjustments . . . . . . 3-25

2.High-Voltage Adjustment (SN 3001A and Below) . . 3-29

2.High-Voltage Adjustment (SN 3004A and Above) . . 3-39

3.Preliminary Display Adjustments (SN 3001A and

4.Final Display Adjustments (SN 3001A and Below) . 3-59

4.Final Display Adjustments (SN 3004A and Above) . 3-61

5.Log Amplifier Adjustments . . . . . . . . . . . . 3-65

6.Video Processor Adjustments . . . . . . . . . . . 3-69

7.3 MHz Bandwidth Filter Adjustments . . . . . . . 3-72

8.21.4 MHz Bandwidth Filter Adjustments . . . . . 3-77

9.3 dB Bandwidth Adjustments . . . . . . . . . . 3-84

10.Step Gain and 18.4 MHz Local Oscillator

Adjustments . . . . . . . . . . . . . . . . . . 3-87

11.Down/Up Converter Adjustments . . . . . . . . 3-92

12.Time Base Adjustment (SN 2840A and Below, also

32 17AO5568 and Above) . . . . . . . . . . . . . 3-95

12.Time Base Adjustment (SN 2848A to 3217A05567) 3-99

13.20 MHz Reference Adjustments . . . . . . . . . 3-103

14.249 MHz Phase Lock Oscillator Adjustments . . . 3-107

15.275 MHz Phase Lock Oscillator Adjustment . . . . 3-110

16.Second IF Amplifier and Third Converter

Adjustment . . . . . . . . . . . . . . . . . . . 3-112

17.Pilot Second IF Amplifier Adjustments . . . . . . 3-116

18.Frequency Control Adjustments . . . . . . . . . 3-119

19.Second Converter Adjustments . . . . . . . . . 3-123

20.50 MHz Voltage-Tuned Oscillator Adjustments . . 3-130

21. Slope Compensation Adjustments . . . . . . . . 3-133

22.Comb Generator Adjustments . . . . . . . . . . 3-136

23.Analog-To-Digital Converter Adjustments . . . . . 3-139

24.Track and Hold Adjustments . . . . . . . . . . . 3-142

25.Digital Storage Display Adjustments . . . . . . . 3-145 Low-Noise DC Supply . . . . . . . . . . . . . . . . 3-150

Contents-2

Crystal Filter Bypass Network Configuration . . . . . 3-151

4. Option 462

Introduction . . . . . . . . . . . . . . . . . . . . .

4. 6 dB Resolution Bandwidth Accuracy Test . . . . .

4.Impulse and Resolution Bandwidth Accuracy Test .

5.6 dB Resolution Bandwidth Selectivity Test . . . .

5.Impulse and Resolution Bandwidth Selectivity Test .

6.Impulse and Resolution Bandwidth Switching Uncertainty Test . . . . . . . . . . . . . . . .

Test 4. 6 dB Resolution Bandwidth Accuracy Test (p/o Table 2-19, Performance Test Record) . . . . . . .

Test 4. Impulse and Resolution Bandwidth Accuracy Test (p/o Table 2-19, Performance Test Record) . .

Test 5. 6 dB Resolution Bandwidth Selectivity (p/o ???Ihble 2-19, Performance Test Record) . . . . . . .

Test 5. Impulse and Resolution Bandwidth Selectivity (p/o Table 2-19, Performance Test Record) . . . . .

Test 6. Impulse and Resolution Bandwidth Switching Uncertainty (p/o ???Iable 2-19, Performace Test Record) . . . . . . . . . . . . . . . . . . . . .

9. 6 dB Resolution Bandwidth Adjustments . . . . .

9.Impulse Bandwidth Adjustments . . . . . . . . .

5.Option 857

Introduction . . . . . . . . . . . . . . . . . . . . .

12. Option 857 Amplitude Fidelity Test . . . . . . .

Performance Test Record . . . . . . . . . . . . . . .

Test 12. Option 857 Amplitude Fidelity Test . . . . .

6.Major Assembly and Component Locations

IF-Display Section Figure Index . . . . . . . . . . . .

RF Section Figure Index . . . . . . . . . . . . . . .

4-l

4-2

4-4

4-10

4-13

4-16

4-18

4-19

4-21

4-22

4-23

4-24

4-27

5-l

5-2

5-7

5-8

6-l

6-2

Contents-3

Figures

l-l. Service Accessories, HP Part Number 08568-60001 . . 2-l. Center Frequency Accuracy Test Setup . . . . . . . .

2-2. Center Frequency Readout Error Measurement . . . .

2-3. Frequency Span Accuracy Test Setup . . . . . . . .

2-4. Sweep Time Accuracy Test Setup . . . . . . . . . .

2-5. Penlift Output Signal . . . . . . . . . . . . . . . .

2-6. Resolution Bandwidth Measurement . . . . . . . . .

2-7. 60 dB Bandwidth Measurement . . . . . . . . . . .

2-8. Bandwidth Switching Uncertainty Measurement . . .

2-9. Attenuator Switching Uncertainty Test Setup . . . . .

2-10. Attenuator Switching Uncertainty Measurement . . .

2-l 1. Frequency Response Test Setup (20 MHz to 1.5 GHz) . 2-12. Frequency Response Measurement (20 MHz to 1.5 GHz) 2-13. Frequency Response Test Setup (100 kHz to 20 MHz) . 2-14. Frequency Response Measurement (100 kHz to 20 MHz) 2-15. Frequency Response Test Setup (100 Hz to 100 kHz) . 2-16. RF Gain Uncertainty Measurement . . . . . . . . .

2-17. IF Gain Uncertainty Test Setup . . . . . . . . . . .

2-18. IF Gain Uncertainty Measurement . . . . . . . . . .

2-19. IF Gain Uncertainty Measurement (2 dB) . . . . . . .

2-20. Log Scale Switching Uncertainty Measurement . . . .

2-21. Amplitude Fidelity Test Setup . . . . . . . . . . . .

2-22. Amplitude Fidelity Measurement . . . . . . . . . .

2-23. Average Noise Level Measurement . . . . . . . . . .

2-24. Residual Responses Measurement . . . . . . . . . .

2-25. Harmonic Distortion Test Setup . . . . . . . . . . .

2-26. Intermodulation Distortion Test Setup . . . . . . . .

2-27. Intermodulation Distortion Products . . . . . . . . .

2-28. Bandwidth Filter Slope Measurement . . . . . . . .

2-29. Slope Detected Residual FM . . . . . . . . . . . . .

2-30. Peak-to-Peak Amplitude Measurement . . . . . . . .

2-31. Line Related Sidebands Measurement . . . . . . . .

2-32. Calibrator Amplitude Accuracy Test Setup . . . . . .

2-33. Fast Sweep Time Accuracy (~20 ms Test Setup) . . . .

2-34. Fast Sweep Time Measurement (~20 ms) . . . . . . .

2-35. 1st LO Output Amplitude Test Setup . . . . . . . . .

2-36. Frequency Reference Test Setup . . . . . . . . . . .

3-l. Low-Voltage Power Supply Adjustments Setup . . . .

3-2. IF-Display Section Low-Voltage Adjustments (SN 3001A and Below) . . . . . . . . . . . . . . . . . . .

3-3. IF-Display Section Low-Voltage Adjustments (SN 3004A and Above) . . . . . . . . . . . . . . . . . . .

3-4. Location of RF Section Low-Voltage Adjustments . . .

3-5. High Voltage Adjustment Setup . . . . . . . . . . .

3-6. Location of High Voltage Adjustments . . . . . . . .

3-7. Location of Label and Test Point . . . . . . . . . . .

l-8 2-3 2-4 2-6 2-9

2-11

2-14

2-16

2-19

2-20

2-21

2-22

2-24

2-25

2-26

2-27

2-32

2-33

2-35

2-36

2-40

2-41

2-43

2-46

2-48

2-50

2-52

2-53

2-57

2-58

2-58

2-61

2-62

2-63

2-64

2-66

2-68

3-25

3-26

3-26

3-27

3-30

3-31

3-32

Contents-4

Contents-5

Contents-6

6-7. IF Section, Bottom View . . . . . . . . . . . . . .

6-10

Contents-7

lhbles

2-l. Performance Test Cross-Reference . . . . . . . . . .

2-2. Center Frequency Readout Error Test Record . . . . .

2-3. Wide Span Error . . . . . . . . . . . . . . . . . .

2-4. Span Error . . . . . . . . . . . . . . . . . . . . .

2-5. Sweep Time Accuracy, Sweep Times 220 ms . . . . .

2-6. Sweep Time Accuracy, Sweep Times ~20 s . . . . . .

2-7. Sweep Time Accuracy, Sweep Times 220 ms (Alternate Procedure) . . . . . . . . . . . . . . . . . . .

2-8. Bandwidth Accuracy . . . . . . . . . . . . . . . .

2-9. Resolution Bandwidth Selectivity . . . . . . . . . .

2-10. Bandwidth Switching Uncertainty . . . . . . . . . .

2-11. Input Attenuator Switching Uncertainty . . . . . . .

2-12. IF Gain Uncertainty, 10 dB Steps . . . . . . . . . .

2-13. IF Gain Uncertainty, 2 dB Steps . . . . . . . . . . .

2-14. IF Gain Uncertainty, 0.1 dB Steps . . . . . . . . . .

2-15. Log Scale Switching Uncertainty . . . . . . . . . . .

2-16. Log Amplitude Fidelity . . . . . . . . . . . . . . .

2- 17. Linear Amplitude Fidelity . . . . . . . . . . . . . .

2-18. Fast Sweep Time Accuracy (~20 ms) . . . . . . . . .

3-1. Adjustment Cross Reference . . . . . . . . . . . . .

3-2. Adjustable Components . . . . . . . . . . . . . . .

3-3. Factory-Selected Components . . . . . . . . . . . .

3-4. Standard Value Replacement Capacitors . . . . . . .

3-5. Standard Value Replacement 0.125 Resistors . . . . .

3-6. Standard Value Replacement 0.5 Resistors . . . . . .

3.5. Initial Adjustment Positions . . . . . . . . . . . . .

3-6. Initial Adjustment Positions . . . . . . . . . . . . .

3-7. Parts for Low-Noise DC Supply . . . . . . . . . . .

3-8. Crystal Filter Bypass Network Configuration for A4A4 and A4A8 (21.4 MHz) . . . . . . . . . . . . . .

3-9. Crystal Filter Bypass Network Configuration for A4A7 (3 MHz) . . . . . . . . . . . . . . . . . . . . .

4-l. 6 dB Resolution Bandwidth Accuracy . . . . . . . .

4-2. Impulse Bandwidth Accuracy . . . . . . . . . . . .

4-3. 6 dB Resolution Bandwidth Accuracy . . . . . . . .

4-4. 6 dB Resolution Bandwidth Selectivity . . . . . . . .

4-5. Impulse and Resolution Bandwidth Selectivity . . . .

4-6. Bandwidth Switching Uncertainty . . . . . . . . . .

5-l. Log Amplitude Fidelity (10 Hz RBW; Option 857) . . .

5-2. Log Amplitude Fidelity (10 kHz RBW; Option 857) . . 5-3. Linear Amplitude Fidelity . . . . . . _ . . . . . . .

2-2

2-5

2-7

2-8

2-11

2-12

2-12

2-14

2-17

2-19

2-21

2-35

2-36

2-38

2-40

2-42

2-44

2-65

3-3

3-5

3-13

3-20

3-21

3-23

3-59

3-62

3-150

3-151

3-151

4-3

4-8

4-9

4-12

4-15

4-17

5-4

5-5

5-6

Contents-E

1

General Information

Introduction

Warning

Instruments Covered

by this Manual

This HP 8568B Tests and Adjustments Manual contains two sections: Performance Tests and Adjustments Procedures. The Performance Tests provided should be performed for the following reasons:

w If the test equipment for the Operation Verification Program is not available.

n If the instrument does not pass all of the Operation Verification tests.

w For complete verification of specifications not covered by the Operation Verification program.

The adjustment procedures should be performed for the following reasons:

w If the results of a performance test are not within the specifications.

w After the replacement of a part or component that affects electrical performance.

The adjustment procedures require access to the interior of the instrument and therefore should only be performed by qualified service personnel. There are voltages at many points in the instrument which can, if contacted, cause personal injury. Be extremely careful. Adjustments should be performed only by trained service personnel.

Power is still applied to this instrument with the LINE switch in STANDBY. There is no OFF position on the LINE switch. Before removing or installing any assembly or printed circuit board, remove the power cord from the rear of both instruments and wait for the MAINS indicators (red LEDs) to go completely out.

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

Use a non-metallic tuning tool whenever possible.

This manual contains procedures for testing and adjusting HP 8568B Spectrum Analyzers, including those with Option 001 (75 Ohm RF INPUT), Option 400 (400 Hz operation), Option 462, and Option 857 installed. The procedures in this manual can also be used to adjust HP 8568A Spectrum Analyzers that have been converted into HP 8568B Spectrum Analyzers through the installation of an HP 8568AB Retrofit Kit (formerly HP 8568A+ OlK Retrofit Kit).

G e n e r a l I n f o r m a t i o n l-1

Operation Verification A high confidence level in the instrument???s operation can be achieved by running only the Operation Verification Program, since it tests most of the instrument???s specifications. It is recommended that the Operation Verification Program be used for incoming inspection and after repairs, since it requires much less time and test equipment.

A description of the program can be found in the Installation and Verification manual.

Option 462

Instruments

Option 857

Instruments

Option 462 instruments require that the performance tests and adjustment procedures listed below be performed instead of their standard versions included in chapters two and three. Information on Option 462 versions are located in Chapter 4, Option 462.

6 dB Bandwidths:

Test 4, 6 dB Resolution Bandwidth Accuracy Test

Test 5, 6 dB Resolution Selectivity Test

Adjustment 9, 6 dB Bandwidth Adjustments

Impulse Bandwidths:

Test 4, Impulse and Resolution Bandwidth Accuracy Test Test 5, Impulse and Resolution Selectivity Test

Test 6, Impulse and Resolution Bandwidth Switching Uncertainty Test

Adjustment 9, Impulse Bandwidth Adjustments

Option 857 instruments require that the performance test procedure listed below be performed instead of the standard version included in Chapter 2. Information on Option 857 is located in Chapter 5, Option

8 5 7 .

Test 12, Option 857 Amplitude Fidelity Test

l-2 G e n e r a l I n f o r m a t i o n

G e n e r a l I n f o r m a t i o n 1 - 3

???Ihble l-l. Recommended Test Equipment (2 of 5)

l-4 G e n e r a l I n f o r m a t i o n

l-6 G e n e r a l I n f o r m a t i o n

???Ihble l-l. Recommended Test Equipment (5 of 5)

* Part of Service Accessories

G e n e r a l I n f o r m a t i o n l-7

Figure l-l. Service Accessories, HP Part Number 08568-60001

l-8 G e n e r a l I n f o r m a t i o n

2

Performance Tksts

Introduction

The procedures in this section test the instrument???s electrical performance using the Specifications in the Installation and Verification Manual as the performance standards. None of the tests require access to the interior of the instrument. The manual

Performance Tests provided in this section should be performed only if semi-automatic test equipment (for Operation Verification) is not available or the Performance Test is not in the Operation Verification Program. (Refer to the Installation and Verification Manual for information on Operation Verification.)

Verification of

Specifications

When a complete verification of specifications is required, proceed as follows:

1.Run the Operation Verification Program.

2.The Operation Verification Program verifies compliance with specifications of all tests it performs. The tests not performed by the Operation Verification Program must be done manually and are as follows:

nCenter Frequency Readout Accuracy

nSpurious Responses

H Fast Sweep Time Accuracy

n1st LO Output Amplitude Responses

nFrequency Reference Error

If the results of a performance test are marginally within specification, go to the Adjustments section of this manual and perform the related adjustment procedures. When an adjustment is directly related to a performance test, the adjustment procedure is referenced under RELATED ADJUSTMENT in the performance test.

Calibration Cycle This instrument requires periodic verification of performance. The instrument should have a complete verification of specifications at least every six months.

P e r f o r m a n c e T e s t s 2-l

Equipment Required Equipment required for the manual performance tests and adjustments is listed in ???Ihble 2-1, Recommended Test Equipment, at the beginning of this manual. Any equipment that satisfies the critical specifications given in the list may be substituted for the recommended model.

Test Record The Operation Verification Program provides a detailed test record when a printer is used with the controller. If manual performance tests are done, results of the performance tests may be tabulated in the HP 8568B Performance Test Record at the end of this section. The HP 8568B Performance Test Record lists all of the tested specifications and the acceptable ranges for the measurement values obtained during the tests.

Note Allow l/2-hour warm-up time for the HP 8568B before beginning the Performance Tests.

able 2-1. Performance Test Cross-Reference

2 - 2 P e r f o r m a n c e T e s t s

1. Center Frequency Readout Accuracy Test

1. Center

Frequency Readout

Accuracy ???I&t

Related Adjustments Frequency Control Adjustments

Time Base Adjustment

Step Gain and 18.4 MHz Local Oscillator Adjustments

50 MHz Voltage-Tuned Oscillator Adjustments

Specification (uncorrected)

f2% of frequency span + frequency reference error x tune frequency +30% of resolution bandwidth setting + 10 Hz) in AUTO resolution bandwidth after adjusting FREQ ZERO at stabilized temperature.

Description A synthesized signal source that is phase-locked to a known frequency standard is used to input a signal to the analyzer. The frequency readout of the analyzer is compared to the actual input frequency

for several different frequency settings over the analyzer???s range. The signal source is phase-locked to a standard known to be as accurate as the analyzer???s internal frequency reference to minimize the ???frequency reference error x center frequency??? term of the specification.

SYNTHESIZED

SHEEPER

SIONAL

INPUT 2

ADAPTER

CABLE ASSENBLY

Figure 2-1. Center Frequency Accuracy Test Setup

P e r f o r m a n c e T e s t s 2-3

1. Center Frequency Readout Accuracy Test

Equipment Synthesized Sweeper . . . . . . . . . HP8340A Frequency Standard . 10 MHz standard, accy within + 1 part in lOlo,

e.g. HP 5061A

Adapter, Type N (m) to SMA (f) . . . HP1250-1250 61 cm (24 in.) Cable Assembly, SMA Male Connectors HP 5061-1086

Procedure 1. Connect CAL OUTPUT to SIGNAL INPUT 2.

2 . Press [INSTR PRESET), @ on the analyzer.

3 . Adjust FREQ ZERO for a maximum amplitude trace.

4 . Press (1tds-r~ PRESET).

5 . Set the synthesized sweeper for a 100.000 MHz signal at a level of approximately 0 dBm.

6 . Connect equipment as shown in Figure 2-l.

7 . Set analyzer ~CENTER FREQUENCY) and [FREQUENCY SPAN) and synthesized sweeper frequency according to Table 2-2. At each setting, press [PEAK SEARCH).~~) to center the signal. Adjust CREFERENCE LEVEL) as necessary to place signal peak at a convenient level.

8.Record the CENTER readout frequency in the table for each setting. The limits for this frequency are given in the table. See Figure 2-2.

Figure 2-2. Center Frequency Readout Error Measurement

2 - 4 Performance Tests

Performance Tests 2 - 5

2. Frequency Span Accuracy lkst

Related Adjustments Frequency Control Adjustments

50 MHz Voltage-Tuned Oscillator Adjustments

Specification

SpanUncertainty

>l MHz f(2% of the actual frequency separation between two points +0.5% of span setting)

51 MHz 445% of the actual frequency separation between two points +0.5% of span setting)

Description Frequency Span accuracy is determined by measuring a frequency at 5% of sweep and then at 95% of sweep. These frequencies correspond

to half a division from each edge of the CRT.

The spans chosen are based on the architecture of the HP 8568B RF hardware:

SYNTHESIZED WEEPER

Figure 2-3. Frequency Span Accuracy Test Setup

2-6 P e r f o r m a n c e T e s t s

Procedure 1. Connect equipment as shown in Figure 2-3.

2.Press QNsTR PRESET] on analyzer.

3.Press [CENTER FREQUENCY] 100 MHz, [FREQUENCY SPAN_) 200 Hz.

4.Connect synthesized sweeper tot spectrum analyzer RF input 2.

5.On synthesized sweeper, select external REFERENCE and key in (jj??? 0 dBm.

6.Press Icw] and key in 99.999 910 MHz.

7.Press MARKER [PEAK SEARCH) on spectrum analyzer and record marker reading under FREQ C of Table 2-3.

8.Set synthesized sweeper frequency to 100.000 090 MHz.

9.Press MARKER [PEAK SEARCH] and record marker reading under FREQ D of Table 2-3.

10.Repeat the span measurement procedure of steps 6 through 9 for each frequency span listed in Table 2-3.

11.Determine the frequency difference between the two measured points. Enter this value under the A DUT column in ???fable 2-3.

12.The frequency span error is the difference between A DUT and A SYNTH. (See table 2-3 for values). Calculate the span error and record it in Table 2-4.

13.Compare the table 2-4 spec to the span error value calculated in step 12.

lhble 2-3. Wide Span Error

I

I

I

I

Performance Tests 2 - 7

2. Frequency Span Accuracy Test

For spans > 1 MHz, the spec is: >*[(.02)(A synth freq) + (.005)(span)]

For spans 2 1 MHz, the spec is: >&[(.05)(A synth freq) + (.005)(span)]

2 - 8 Performance Tests

3. Sweep Time Accuracy Test (220 ms)

3. Sweep Time Accuracy Test (220

ms)

Related Adjustment Frequency Control Adjustments

Specification *lo% for sweep times 5100 seconds &20% for sweep times >lOO seconds

Description Preferred Procedure

This test is for sweep times 220 ms. For faster sweep times, refer to

Fast Sweep Time Accuracy Test (Test 19).

A universal counter is connected to the PENLIFT RECORDER OUTPUT (on the rear panel) of the spectrum analyzer. The counter is used in time interval mode to determine the ???pen down??? (sweep time) interval of the PENLIFT RECORDER OUTPUT. The penlift output voltage level corresponds directly to the sweeping of the analyzer (pen down = OV) and not-sweeping of the analyzer (pen up = 15V). A DVM is used to set the appropriate trigger level for the counter.

Alternate Procedure

Perform this procedure if the equipment for the preferred procedure is unavailable.

Sweep time accuracy for sweep times 220 ms can also be measured using the HP 8568B???s internal frequency counter for a time interval measurement.

SPECTRUM ANALYZER

UNIVERSAL

COUNTER

DIGITAL VOLTMETER

\

Figure 2-4. Sweep Time Accuracy Test Setup

Performance Tests 2 - 9

3. Sweep Time Accuracy Test (220 ms)

Equipment Universal Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 5316A Digital Voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

Procedure

Sweep Times 220 ms 1. Connect equipment as shown in Figure 2-4.

2.Press [INSTR PRESET) on the spectrum analyzer.

3.Key in the following settings:

4.Set up the universal counter as follows:

a. Set all front panel keys in ???out??? position. b. Set POWER switch to ON.

c.Set GATE TIME vernier control to 9 o???clock. d. Set SEPXOM A switch to COM A position.

e. Depress T.I. A + B switch (making sure the blue shift key is out).

f. Set Channel A trigger level to trigger on negative slope. g. Set Channel B trigger level to trigger on positive slope. h. Set both Channel A and Channel B ac/dc switches to de.

i.Connect the digital voltmeter to Channel A TRIGGER LEVEL OUT. (Be sure to ground the DVM properly.)

j. Adjust Channel A trigger level to set a DVM voltage reading of 0.3 v.

k. Repeat steps i and j for Channel B.

5.Set analyzer @WEEP TIME) to 20 ms. Allow the universal counter enough time to settle at this sweep time.

2-10 P e r f o r m a n c e T e s t s

3. Sweep Time Accuracy Test (220 ms)

NOTE:PULSE WIDTH APPROXIMATE

Figure 2-5. Penlift Output Signal

6.Note the measured sweep time on the universal counter and record this value in Table 2-5. The measured sweep time should be a value between the minimum and maximum values given in Table 2-5.

7.Repeat steps 5 and 6 for each sweep time setting in Table 2-5.

???Ihble 2-5.

Sweep Time Accuracy, Sweep Times 220 ms

8.Press MARKER (NORMAL].

9.Use @J to place the marker at the second vertical graticule. 10. Press @FiHIFT),[Xi!FF~.

11.Set analyzer [SWEEP TIME) to 20 s. Allow the universal counter enough time to settle at this sweep time.

12.Note the measured sweep time on the universal counter and

record this value in Table 2-6. The measured sweep time should be a value between the minimum and maximum values given in Table 2-6.

13. Repeat steps 11 and 12 for 200 s sweep time.

P e r f o r m a n c e T e s t s 2-11

3. Sweep Time Accuracy Test (220 ms)

???Ihble 2-6.

Sweep Time Accuracy, Sweep Times 220 s

Sweep Times 220 ms (Alternate Procedure)

Start-Up Time

Measurement

Sweep Time

Measurement

14.Sweep times 220 ms are tested without external test equipment by the following procedure.

15.Press ~NSTR PRESET).

16.Set @WEEP TIME] according to Table 2-7. Press MARKER (j-1. Rotate the DATA knob to place the marker on the left edge of the CRT display. Key in CSHIFT) [my.

17.Press [SHIFT) [REsy three times. The Active Function Block reads SWEEP GEN followed by a measured sweep time. This is the start-up time. Record it in ???Ihble 2-7. The start-up time must be subtracted from the SWEEP GEN time measured in step 19. (Adding the start-up time to the [SWEEP TIME] setting effectively subtracts it from the SWEEP GEN time.)

18.Press MARKER (OFF).

19.Press @?i] (REST three times and note the SWEEP GEN reading. The limits for the SWEEP GEN reading are listed in Table 2-7. (For example, assume the start-up time measured in step 17 was 700 ,US for a [SWEEP TIME) of 20 ms. The limits for the SWEEP GEN readings would be 19.3 to 22.7 ms.)

20.Repeat steps 16 to 19 for each sweep time shown in Table 2-7.

lhble 2-7.

Sweep Time Accuracy, Sweep Times 220 ms (Alternate Procedure)

2 - 1 2 P e r f o r m a n c e T e s t s

4. Resolution

Bandwidth

Accuracy Test

4. Resolution Bandwidth Accuracy Test

(For instruments with Option 462, refer to Chapter 4.)

Related Adjustment 3-dB Bandwidth Adjustments

Specification &20%, 3 MHz

+lO%, 3 kHz to 1 MHz

&20% 10 Hz to 1 kHz

30 kHz and 100 kHz bandwidth accuracy figures apply only with 190% Relative Humidity, < 40??C.

Description The 3 dB bandwidth for each resolution bandwidth setting is measured with the MARKER function to determine bandwidth

accuracy. The CAL OUTPUT is used for a stable signal source.

Equipment None Required

Procedure 1. Press [INSTR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Key in spectrum analyzer setting as follows:

(CENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 MHZ

4.Press SCALE LIN pushbutton. Press csHIFT],[my (resolution bandwidth).

5.Adjust [REFERENCE LEVEL] to position peak of signal trace at reference level (top) graticule line. Press SWEEP [SINGLE).

6.Press MARKER [ml and place marker at peak of signal trace with DATA knob. Press MARKER In] and position movable marker 3 dB down from the stationary marker on the positive-going edge of the signal trace (the MARKER A amplitude readout should be -3.00 dB ho.05 dB). It may be necessary to press SWEEP ICONT) and adjust [CENTER FREQUENCY) to center trace on screen.

7.Press MARKER (ZJ and position movable marker 3 dB down from the signal peak on the negative going edge of the trace (the MARKER A amplitude readout should be .OO dB f0.05 dB). The 3 dB bandwidth is given by the MARKER A frequency readout (see Figure 2-6). Record this value in Table 2-8.

P e r f o r m a n c e T e s t s 2-13

4. Resolution Bandwidth Accuracy Test

Figure 2-6. Resolution Bandwidth Measurement

8.Vary spectrum analyzer settings according to ???fable 2-8. Measure the 3 dB bandwidth for each resolution bandwidth setting by the procedure of steps 6 and 7 and record the value in ???Ihble 2-8. The measured bandwidth should fall between the limits shown in the table.

???Ihble 2-8. Bandwidth Accuracy

2 - 1 4 P e r f o r m a n c e T e s t s

5.Resolution Bandwidth Selectivity Test

6.Read the 60 dB bandwidth for the 3 MHz resolution bandwidth setting from the MARKER A frequency readout (see Figure 2-7) and record the value in Table 2-9.

7.Vary spectrum analyzer settings according to Table 2-9. Measure the 60 dB bandwidth for each resolution bandwidth setting by the

procedure of steps 4 through 6 and record the value in ???fable 2-9.

8.Record the 3 dB bandwidths from Table 2-8 in Table 2-9.

9.Calculate the bandwidth selectivity for each setting by dividing the 60 dB bandwidth by the 3 dB bandwidth. The bandwidth ratios should be less than the maximum values shown in

???fable 2-9.

10.The 60 dB bandwidth for the 10 Hz resolution bandwidth setting should be less than 100 Hz.

Figure 2-7. 60 dB Bandwidth Measurement

2 - 1 6 P e r f o r m a n c e T e s t s

5. Resolution Bandwidth Selectivity Test

???lhble 2-9. Resolution Bandwidth Selectivity

P e r f o r m a n c e T e s t s 2 - 1 7

6. Resolution

Bandwidth

Switching

Uncertainty Test

(For instruments with Option 462, refer to Chapter 4.)

Related Adjustments 3 MHz Bandwidth Filter Adjustments

21.4 MHz Bandwidth Filter Adjustments Down/Up Converter

Adjustments

Specification (uncorrected; referenced to 1 MHz bandwidth; 20 - 30??C after 1 hour warm-up) k2.0 dB, 10 Hz bandwidth

f0.8 dB, 30 Hz bandwidth *0.5 dB, 100 Hz to 1 MHz bandwidth

fl.O dB, 3 MHz bandwidth 30 kHz and 100 kHz bandwidth switching uncertainty figures only applicable 190% Relative Humidity

Description The CAL OUTPUT signal is applied to the input of the spectrum analyzer. The deviation in peak amplitude of the signal trace is then measured as each resolution bandwidth filter is switched in.

Equipment None Required

4 . Press LOG (ENTER dB/bIvj and key in 1 dB. Press MARKER

[PEAK SEARCH) a.

5 . Press m,@J

6 . Key in settings according to Table 2-10. Press MARKER

[PEAK SEARCH] at each setting, then read the amplitude deviation from the MARKER A readout at the upper right of the display (see Figure 2-8). The allowable deviation for each resolution bandwidth setting is shown in the table.

2 - 1 8 P e r f o r m a n c e T e s t s

6. Resolution Bandwidth Switching Uncertainty Test

Figure 2-8. Bandwidth Switching Uncertainty Measurement

???Ihble 2-10. Bandwidth Switching Uncertainty

Performance Tests 2-l 9

7.Input Attenuator Switching Uncertainty Test

6.Press MARKER CPEAK SEARCH),(KJ

7.Set [~~J???JREFERENCE LEVEL], and frequency synthesizer

amplitude according to Table 2-l 1. At each setting, press MARKER (PEAK SEARCH) and record the deviation from the 10 dB setting from the MARKER A amplitude readout (see Figure 2-10). The deviation should not exceed *l.O dB at any setting.

HKR A 0 Hz

Performance Tests 2 - 21

8. Frequency

Response Test

Related Adjustment Slope Compensation Adjustment

Specification SIGNAL INPUT 1

~tl.5 dB, 100 Hz to 1.5 GHz

*I dB, 100 Hz to 500 MHz

SIGNAL INPUT 2

fl dB, 100 kHz to 1.5 GHz

Description Frequency response at both analyzer inputs is tested by slowly sweeping a flat signal source over the frequency range and observing the peak-to-peak variation in trace amplitude. The test is divided into three parts. First, the response is tested from 20 MHz to 1.5 GHz

with a power-meter-leveled synthesized sweeper. Next, a frequency synthesizer is used to check the response from 100 kHz to 20 MHz. Finally, SIGNAL INPUT 1 is tested from 100 Hz to 100 kHz with a function generator.

SPECTRUM ANALYZER

SYNTHESIZED SWEEPER

POWER METER

R E C O R D E R

O U T P U T

I G N A L

N P U T

.\ I

ADA,PT,ERS

POWER SENSOR

O P T I O N 0 0 1 . A D D 5 0 OHMS/75 O H M P A D A N D A D A P T E R

gb12b

Figure 2-11. Frequency Response Test Setup (20 MHz to 1.5 GHz)

2 - 22 Performance Tests

8. Frequency Response Test

Note Equipment listed is for three test setups, Figure 2-11, Figure 2-13, and Figure 2-15.

Equipment Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3312A Power Splitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11667A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0780 Adapter, Type N (m) to BNC (m) . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0082 Adapter, Type N (m) to Type N (m) . . . . . . . . . . . . . . . . . . . . HP 1250-0778 Adapter, Type N (m) to SMA (f) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-1250 Adapter, APC-3.5 (f) to APC-3.5 (f) . . . . . . . . . . . . . . . . . . . . HP 1250-1749 Cable, SMA Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 5061-5458

Additional Equipment for Option 001:

5OfY700 Minimum Loss Pad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11852A Adapter, Type N (f) to BNC (m) (7561) . . . . . . . . . . . . . . . . . . HP 1250-1534

Procedure

20 MHz to 1.5 GHz 1. Press ~NSTR PRESET) on spectrum analyzer and synthesized sweeper.

3.Connect equipment as shown in Figure 2-l 1. The RECORDER OUTPUT on rear panel of power meter is connected to LEVELING EXT INPUT of the synthesized sweeper. One output arm of the power splitter is connected directly to SIGNAL INPUT 2 of the spectrum analyzer via the N-to-N adapter. The power sensor connects directly to the other splitter output.

4.Depress RANGE HOLD button on power meter.

5.Select METER leveling on synthesized sweeper.

6.Key in the following spectrum analyzer settings:

[CENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ

P e r f o r m a n c e T e s t s 2.23

8. Frequency Response Test

7.Adjust POWER LEVEL on synthesized sweeper (using data knob) to place peak of 20 MHz signal near reference level (top) graticule line.

8.Press [ENTER dB/mv], 1 dB on spectrum analyzer. Adjust POWER LEVEL on synthesized sweeper to position peak of signal 2 divisions below the reference level line.

9 . Key in the following spectrum analyzer settings:

START FREQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.MHz

10.Press TRACE A [MAX) on the analyzer.

11.Press SWEEP SINGLE on the synthesized sweeper.

DL -.B

dBm

,I

Figure 2-12. Frequency Response Measurement (20 MHz to 1.5 GHz)

12.Press DISPLAY LINE [ENTER) on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record measurements below.

SIGNAL INPUT 2

(20 MHz to 1.5 GHz)

MaximumdBm

MinimumdBm

13.To check SIGNAL INPUT 1, use the type N male to BNC male adapter to connect the power splitter directly to SIGNAL INPUT 1.

Option 001: Use HP 11852A Minimum Loss Pad and adapters between splitter and spectrum analyzer input.

14. Press [INSTR PRESET) on spectrum analyzer, then activate SIGNAL INPUT 1 with the pushbutton.

2 - 24 Performance Tests

8. Frequency Response Test

Option 001: Set [REFERENCE LEVEL] TO -6.0 dBm.

15.Repeat steps 6 through 11. Press DISPLAY LINE [ENTER) on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record measurements below.

SIGNAL INPUT 1

(20 MHz to 1.5 GHz)

MaximumdBm

MinimumdBm

16.Press MARKER (-1 on spectrum analyzer. Set marker to 500 MHz. Press DISPLAY LINE (ENTER] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points between 20 MHz and 500 MHz. Record measurements below.

SIGNAL INPUT 1

(20 MHz to 500 GHz)

MaximumdBm

MinimumdBm

100 kHz to 20 MHz 17. Set the frequency synthesizer controls as follows:

FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 MHz

SWEEP WIDTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19.9 MHz

AMPLITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 2 dBm

(Option 001: + 4 dBm)

18.Connect equipment as shown in Figure 2-13. The output of the frequency synthesizer should be connected to SIGNAL INPUT 1.

Option 001: Use HP 11852 Minimum Loss Pad and adapters.

SPECTRUM ANALYZER

FREQUENCY SYNTHESIZER

II

l-fADAPTER

OPTIOW 001: MO 80 oHMa/ 78 ON88 PM AW AIDAPTUII

Figure 2-13. Frequency Response Test Setup (100 kHz to 20 MHz)

19. Press ~NSTR PRESET) on the spectrum analyzer. Activate SIGNAL INPUT 1 with the pushbutton.

20. Key in the following spectrum analyzer settings:

Performance Tests 2 - 25

8. Frequency Response Test

25.After completion of sweep, press DISPLAY LINE (j?KiK] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record the measurements below.

SIGNAL INPUT 1 (100 kHz to 20 MHz)

MaximumdBm

MinimumdBm

26. Measure and record signal level at start of trace (100 kHz).

SIGNAL INPUT 1 (100 kHz)

dBm

27.Connect output of frequency synthesizer to SIGNAL INPUT 2. Activate this input with the pushbutton.

Option 001. Do not use HP 11852A Minimum Loss Pad. Set frequency synthesizer output amplitude to -2 dBm.

28.Press TRACE A CCLEAR-WRITE) and DISPLAY LINE (OFF) on spectrum analyzer.

29.Set frequency synthesizer FREQUENCY to 20 MHz. Set spectrum

analyzer (CENTER FREQUENCY_) to 20 MHz, and (FREQUENCY SPAN) to

1MHz.

30.Repeat steps 22 through 24.

31.After completion of sweep, press DISPLAY LINE [ENTER] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. Record the measurements below.

SIGNAL INPUT 2

(100 kHz to 20 MHz)

MaximumdBm

MinimumdBm

Figure 2-15.

Frequency Response Test Setup (100 Hz to 100 k=)

P e r f o r m a n c e T e s t s 2-27

8. Frequency Response Test

100Hzto 100 kHz 32. Press (INSTR PRESET) on the spectrum analyzer. Activate SIGNAL INPUT 1.

33. Key in the following spectrum analyzer settings:

34.Connect equipment as shown in Figure 2-15 with function generator to SIGNAL INPUT 1.

35.Set the function generator controls as follows:

LINE . . . . . . . . . . . . . . . . . . .. . . . . . .. . . . . . . . . . . . . . . . . . . . ON

RANGE Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 K

FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -

OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAL (button in)

AMPLITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 V

AMPLITUDE VERNIER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . midrange

SYM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAL

TRIGGER PHASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FREE RUN

MODULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . all out

MODULATION RANGE Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I

M O D U L A T I O N R A N G E H z V E R N I E R . . . . . . . f u l l y C C W

MODULATION SYM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CAL

Percent Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ..fullyCW

36.Adjust function generator FREQUENCY to place signal between the last two graticule lines (right side) on the signal analyzer display.

37.Adjust AMPLITUDE VERNIER on the function generator until the peak of the signal is at the reference graticule line on the spectrum analyzer display.

38.Press LOG CENTER dB/DIv_) 1 dB on the spectrum analyzer. Press DISPLAY LINE [ENTER] and set the Display Line to the level recorded for 100 kHz in step 25.

39.Adjust function generator AMPLITUDE VERNIER to place peak of signal at the Display Line.

40.Adjust FREQUENCY on the function generator to position the signal trace at the right edge of the spectrum analyzer display (last graticule line).

41.Press MODULATION SWP on the function generator and allow the function generator to make at least two complete sweeps. Press

TRACE A [MAX HOLD). Allow the function generator to make one complete sweep. After completion of the sweep, press TRACE A

m).

2.28 P e r f o r m a n c e T e s t s

8. Frequency Response Test

42.Press DISPLAY LINE [ENTER] on the spectrum analyzer. Use the Display Line to measure the maximum and minimum points on the trace. (Disregard LO Feedthrough at 1 kHz.) Record the measurements below.

SIGNAL INPUT 1

(1 kHz to 100 kHz)

MaximumdBm

MinimumdBm

43.Set Display Line to peak of trace at 1 kHz.

44.Key in the following spectrum analyzer settings:

TRACE A (CLEAR-WRITE)

. . . . . . . . . . . . . . . . . . . . .l kHz 1 kHz iO0 Hz

45. Set function generator controls as follows:

RANGE Hz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 (button) FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 MODULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..all out

46.Adjust function generator FREQUENCY as necessary to place signal near center graticule line and adjust AMPLITUDE VERNIER to place peak of signal at Display Line.

47.Key in the following spectrum analyzer settings:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Hz

&TT!, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Hz

48. Set (CF STEP SIZE] to 100 Hz. Step spectrum analyzer

( C E N T E R FFIEQUENCY] from 1 kHz to 100 Hz with a, while setting function generator FREQUENCY to match spectrum analyzer center frequency at each step. Record level-at each setting.

P e r f o r m a n c e T e s t s 2 - 2 9

8. Frequency Response Test

49.For each input, subtract the lowest minimum level (greatest negative) from the highest maximum (least negative) measurement recorded in steps indicated. The result should not exceed 2 dB.

SIGNAL INPUT 1

100 Hz to 500 MHz (from steps 16, 25, 42, or 48)

SIGNAL INPUT 2

100 kHz to 1.5 GHz (from steps 12 or 31)

50.Subtract the lowest minimum level (greatest negative) from the highest maximum (least negative) measurement recorded in steps indicated. The result should not exceed 3 dB.

SIGNAL INPUT 1

100 Hz to 1.5 GHz (from steps 15, 16, 25, 42, or 48)

2.30 P e r f o r m a n c e T e s t s

9. RF Gain Uncertainty Test

h

Figure 2-16. RF Gain Uncertainty Measurement

2 - 3 2 P e r f o r m a n c e T e s t s

10. IF Gain Uncertainty Test

10. IF Gain

Uncertainty Test

Related Adjustments Step Gain and 18.4 MHz Local Oscillator Adjustments

21.4 MHz Bandwidth Filter Adjustments

Specification Assuming the internal calibration signal is used to calibrate the reference level at -10 dBm and the input attenuator is fixed at 10 dB, any changes in reference level from the -10 dB setting will contribute to IF gain uncertainty as shown:

-56.0 dBm to -129.9 dBm Res BW 230 Hz, f1.0 dB; Res BW = 10 Hz, f2.0 dB

Description The IF gain steps are tested over the entire range from 0 dBm to -129.9 dBm using an RF substitution method. The 10 dB, 2 dB, and 0.1 dB steps are compared against a calibrated signal source provided by an HP 3335A Frequency Synthesizer.

Figure 2-17. IF Gain Uncertainty Test Setup

Performance Tests 2 - 33

10. IF Gain Uncertainty Test

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0780

Procedure 1. Press ( INSTR pfwm-).

2.Connect CAL OUTPUT to SIGNAL INPUT.

3.Press Cm] 8. Adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm 50.02 dB.

4.Press (1~~733 PRESET).

10 dB Gain Steps 5. Set the frequency synthesizer for an output frequency of 20.0010 MHz and an output power level of -2.0 dBm. Set the amplitude increment for 10 dB steps.

6.Connect the equipment as shown in Figure 2-17.

7.Key in analyzer settings as follows:

CCENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.001 MHZ

CFREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 kHz

8 Press MARKER (PEAK SEARCH).~~) or adjust (CENTER FREQUENCY) to center signal trace on display.

10.Press MARKER [PEAK SEARCH),

11.Press (SHIFT),(m]I to permit extended reference level settings.

12.Set the analyzer (REFERENCE LEVEL],(VIDEO], and frequency synthesizer amplitude according to Table 2-12 settings. (Use the frequency synthesizer @J for 10 dB steps.) At each setting, note the MKR A amplitude displayed in the upper right corner of the analyzer display (deviation from the 0 dB reference setting) and record it in the table. See Figure 2-18.

Note After measurement at the (REFERENCE LEVEL) = -70 dBm setting, press [SHIFT),(ENTER dB/DIvP as indicated in ???lhble 2-12.

2 - 34 Performance Tests

10. IF Gain Uncertainty Test

???Ihble 2-12. IF Gain Uncertainty, 10 dB Steps

Figure 2-18. IF Gain Uncertainty Measurement

Performance Tests 2 - 35

10. IF Gain Uncertainty Test

2 dB Gain Steps 13. Press QNSTR pREsETj,(jRECALL) 7.

14.Set [REFERENCE LEVEL] to -1.9 dBm.

15.Press MARKER (OFF). Set CVlDEo] to 100 Hz.

16.Set the frequency synthesizer for an output power level of -3.9 dBm. Set the amplitude increment for 2 dB steps.

17.Press MARKER [PEAK SEARCH),@

18.Set the analyzer CREFERENCE LEVEL) and the frequency synthesizer amplitude according to ???Iable 2-13. At each setting, note the MKR A amplitude and record it in the table.

???lhble 2-13. IF Gain Uncertainty, 2 dB Steps

LREFERENCE LEVEL) Frequency Deviation

CdBm) Synthesizer (MARKER A

Amplitude ???Amplitude

YKRAE Hz

1 m/

Figure 2-19. IF Gain Uncertainty Measurement (2 dB)

2 - 36 Performance Tests

10. IF Gain Uncertainty Test

0.1dB Gain Steps 19. Set [REFERENCE LEVEL) to 0 dB.

20.Set the frequency synthesizer for an output power level of -2.00 dBm. Set the amplitude increment for 0.1 dB steps.

21.Press MARKER [PEAK SEARCH),@.

22.Set the analyzer and the frequency synthesizer amplitude according to lkble 2-14. At each setting, note the MKR A amplitude and record it in the table.

23.Find the largest positive deviation and the largest negative

deviation for reference level settings from 0 dBm to -70 dBm in Table 2-12. Also, find the largest positive and negative deviations for the last five settings in the table.

AB

Reference Level Range: 0 to -70 dBm -80 to -120 dBm

24.Find the largest positive and negative deviations in ???lkble 2-13 and Yhble 2-14:

Performance Tests 2 - 37

10. IF Gain Uncertainty Test

???Ihble 2-14. IF Gain Uncertainty, 0.1 dB Steps

25.The sum of the positive deviations recorded in A, C, and D should not exceed 0.6 dB.

26.The sum of the negative deviations recorded in A, C, and D should not be less than -0.6 dB.

27.The sum of the positive deviations recorded in A, B, C, and D should not exceed 1.0 dB.

28.The sum of the negative deviations recorded in A, B, C, and D should not exceed - 1 .O dB.

2 . 3 8 P e r f o r m a n c e T e s t s

11. Log Scale Switching Uncertainty Test

b

2 dB/

Figure 2-20. Log Scale Switching Uncertainty Measurement

able 2-15. Log Scale Switching Uncertainty

2-40 P e r f o r m a n c e T e s t s

Incremental

ho.1 dB/dB over 0 to 80 dB display Cumulative

3 MHz to 30 Hz Resolution Bandwidth

<kl.O dB max over 0 to 80 dB display (20 - 30??C). 5% 1.5 dB max over 0 to 90 dB display

Linear:

f3% of Reference Level for top 9-l/2 divisions of display

Description Amplitude fidelity in log and linear modes is tested by decreasing the signal level to the spectrum analyzer in 10 dB steps with a calibrated signal source and measuring the displayed amplitude change with the analyzer???s MARKER A function.

SIGNAL ANALYZER

SYNTHESIZERf LEVEL

GENERA OR

ADAPTER

?

Figure 2-21. Amplitude Fidelity Test Setup

P e r f o r m a n c e T e s t s 2-41

12. Amplitude Fidelity Test

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . HP 1250-0780

Procedure Log Fidelity

1. Set the frequency synthesizer for an output frequency of 20.000 MHz and an output power level of + 10 dBm. Set the amplitude increment for 10 dB steps.

2.Connect equipment as shown in Figure 2-21.

3.Press ~NSTR PRESET) on the analyzer. Key in analyzer settings as follows:

[ C E N T E R F R E Q U E N C Y ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ FREQUENCY S P A N ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 kHz

CREFERENCE LEVEL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 10 dBm

4.Press MARKER SPEAK SEARCHJ@~K~GTJ~MKR + REF LVL) to

center the signal on the display.

5.Key in the following analyzer settings:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O Hz

[&Xi, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Hz

6.Press MARKER A. Step the frequency synthesizer output amplitude from + 10 dBm to -80 dBm in 10 dB steps, noting the MARKER A amplitude (a negative value) at each step and

recording it in column 2 of ???fable 2-16. Allow several sweeps after each step for the video filtered trace to reach its final amplitude (see Figure 2-22).

7.Subtract the value in column 1 from the value in column 2 for each setting to find the fidelity error.

2 - 42 Performance Tests

12. Amplitude Fidelity Test

8.The fidelity error for amplitude steps from -10 dB to -80 dB should be <& 1.0 dB.

9.The fidelity error at the -90 dB setting should be s&l.5 dB.

YKR A

REF 9.7 d&n ATTEN 20 dB

4J

10 d0/

Figure 2-22. Amplitude Fidelity Measurement

Linear Fidelity 10. Key in analyzer settings as follows:

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .I MHz

[M, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 MHz

11.Set the frequency synthesizer for an output power level of + 10 dBm.

12.Press SCALE LIN pushbutton. Press MARKER

CPEAK SEARCHJ[MKR) to center the signal on the display.

13.Set (FREQUENCY SPAN) to 0 Hz and [VlDEo] to 1 Hz. Press @???iYiF),[XF6-~ (resolution bandwidth), MARKER a.

14.Decrease frequency synthesizer output amplitude by 10 dB steps, noting the MARKER A amplitude and recording it in column 2 of

???Ikble 2-17.

Performance Tests 2 - 43

12. Amplitude Fidelity Test

???Ihble 2-17. Linear Amplitude Fidelity

2 - 44 Performance Tests

13. Average Noise Level Test

13. Average Noise

Level Tkst

Specification c-135 dBm for frequencies >I MHz, c-112 dBm for frequencies <l MHz but >500 Hz with 10 Hz resolution bandwidth, 0 dB input attenuation, 1 Hz video filter.

Option 001: c-129 dBm for frequencies >l MHz, c-106 dBm for frequencies 51 MHz but >500 Hz with 10 Hz resolution bandwidth, 0 dB input attenuation, 1 Hz video filter (SIGNAL INPUT 1 only).

Description The average noise level is checked by observing the displayed noise level at several frequencies with no input signal applied.

Equipment 50 Ohm Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 11593A

Procedure 1. Press (~NsTR PRESET].

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Press m @. Adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm 50.02 dB.

4.Press ~NSTR PRESET].

5.Disconnect CAL OUTPUT from analyzer. Terminate SIGNAL INPUT 2 with a 509 coaxial termination.

6.Key in spectrum analyzer settings as follows:

7.Press SWEEP (SINGLE] and wait for completion of the sweep.

8.Press DISPLAY LINE [ENTER). Using DATA knob, place display line at the apparent average amplitude of the noise trace (see Figure 2-23).

Performance Tests 2 - 45

13. Average Noise Level Test

Figure 2-23. Average Noise Level Measurement

9.Read the average noise level from the DISPLAY LINE readout. The value should be c-112 dBm.

dBm

10.Change [CENTER FREQUENCY) to 1.001 MHz. Follow the procedure to steps 7 through 9 to determine the average noise level. The value should be c-135 dBm.

dBm

11.Change (-CENTER FREQUENCY) to 1501 Mhz. Follow the procedure of steps 7 through 9 to determine the average noise level. The value should be <- 135 dBm.

dBm

2 - 46 Performance Tests

14. Residual Responses Test

14. Residual

Responses Test

Specification c-105 dBm for frequencies >500 Hz with 0 dB input attenuation (no signal present at input) Option 100:

c-99 dBm for frequencies >500 Hz with 0 dB input attenuation (SIGNAL INPUT 1 only).

Option 400:

c-95 dBm for frequencies >500 Hz with 0 dB input attenuation. c-105 dBm for frequencies >2.5 kHz with 0 dB input attenuation.

Description The spectrum analyzer is checked for residual responses across its frequency range with no signal applied to the input and 0 dB input attenuation.

Equipment 50 Ohm Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11593A

Procedure 1. Press (INSTR PRESET].

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Press IRECALL) @J Adjust AMPTD CAL for a MARKER amplitude of -10.00 dbm f0.02 dB.

4.Press QNSTR PRESET).

5.Disconnect CAL OUTPUT from analyzer. Terminate SIGNAL INPUT 2 with a 50 ohm coaxial termination.

6.Key in control settings as follows:

7.Press DISPLAY LINE CENTER_) and key in -105 dBm.

8.Reduce [RESBW) or [VlDEOBW), if necessary, for a margin of at least 4 dB between the noise trace and the display line (refer to Figure 2-24). Do not reduce either bandwidth to less than 300 Hz.

Note This test will require approximately 30 minutes to complete using the settings given in step 6. If the resolution bandwidth or video bandwidth are further reduced, a full band check of residual responses will take up to 15 hours to complete

Performance Tests 2 - 47

14. Residual Responses Test

Figure 2-24. Residual Responses Measurement

9.Press SWEEP [SINGLE_) and wait for completion of sweep. Look for any residual responses at or above the display line. If a residual is suspected, press SWEEP CRINGLE) again and see if the response persists. A residual will persist on repeated sweeps, but a noise peak will not. Any residual responses must be c-105 dBm.

Option 400:

Any residual 500 Hz to 2.5 kHz must be c-95 dBm; any residuals >2.5 kHz must be c-105 dBm

10.If a response appears marginal, do the following to determine whether or not it exceeds the specification.

a.Press ISAVE_) 0.

b.Press MARKER [NORMAL) and place the marker on the peak of the response in question.

c.Press MARKER Ijj), then activate SWEEP m.

d.Reduce [FREQUENCY SPAN] to 1 MHz or less. The amplitude of the response should be c-105 dBm (below the display line).

e.Press (RECALL] (iJ to resume the search for residuals.

11.Step [CENTER FREQUENCY) to 1510 MHz with @) checking for residual responses at each step by the procedure of steps 9 and

10.There should be no residual responses at or above the display line below 1500 MHz.

Maximum Residual Response

dBm

MHz

2 - 46 Performance Tests

15. Spurious Responses Test

15. Spurious

Responses Test

Related Adjustment Second Converter Adjustments

Specification For total signal power of c-40 dBm at the input mixer of the analyzer, all image and out-of-band mixing responses, harmonic and intermodulation distortion products are >75 dB below the total signal power for input signals 10 Mhz to 1500 MHz; >70 dB below the total signal power for input signals 100 Hz to 10 MHz.

Second Harmonic Distortion

For a signal -30 dBm at the mixer and 210 MHz, second harmonic distortion is >70 dB down; 60 dB down for signals ~10 MHz.

Third Order Intermodulation Distortion

For two signals each -30 dB at the mixer, third-order intermodulation products are:

Description Harmonic distortion (second and third) is tested using a signal source and a low-pass filter. The LPF insures that the harmonics measured are generated by the spectrum analyzer and not by the signal source.

Spurious responses due to image frequencies, out-of-band mixing, and intermodulation distortion are measured by applying signals from two separate sources to the spectrum analyzer input.

P e r f o r m a n c e T e s t s 2-49

15. Spurious Responses Test

SPECTRUM ANALYZER

SYNTHESIZED SMEEPEA

10 DB

ATTENUATOR

300 MHZ LPF

J

Figure 2-25. Harmonic Distortion Test Setup

Note Equipment listed is for two test setups, Figure 2-25 and Figure 2-26.

Procedure Harmonic Distortion

1.Connect equipment as shown in Figure 2-25.

2.On the spectrum analyzer, press [INSTR PRESET). Set the controls of the spectrum analyzer as follows:

3. On the synthesized sweeper, key in ~NSTR PRESET], Icw) 280 MHz,

( P O W E R L E V E L ) - 10 dBm.

4.On the spectrum analyzer, key in DISPLAY LINE CENTER] -90 dBm, MARKER [PEAK SEARCH] to position a marker on the peak of the displayed 280 MHz signal.

5.On the synthesized sweeper, press ~POWER LEVEL] and use the ENTRY knob to adjust the amplitude of the displayed 280 MHz

2-50 P e r f o r m a n c e T e s t s

15. Spurious Responses Test

signal for a marker indication of -20.00 dBm (-30.0 dBm at the input mixer with 10 dBm of input attenuation).

6 On the spectrum analyzer, key in MARKER @,

CCENTER FREQUENCY) 560 MHz, MARKER CPEAK SEARCH) to position a second marker on the peak of the second harmonic distortion product of the 280 MHz input signal. The response should be below the display line (>70 dB below the input signal level).

7.On the synthesized sweeper, key in ~POWER LEVEL) ato decrease the amplitude of the 280 MHz signal by 10 dB.

8.On the spectrum analyzer, key in MARKER loFF),

CCENTER FREQUENCY) 280 MHz, [REFERENCE LEVEL) -30 dBm, DISPLAY LINE [ENTER] -105 dBm, MARKER CPEAK SEARCH) to position a marker on the peak of the displayed 280 MHz signal.

9.On the synthesized sweeper, press [POWER LEVEL] and use the ENTRY knob to adjust the amplitude of the displayed 280 MHz signal for a marker indication of -30.00 dBm (-40.0 dBm at the input mixer with 10 dBm of input attenuation).

10.On the spectrum analyzer, key in MARKER a],

[CENTER FREQUENCY) 840 MHz, MARKER [PEAK SEARCH) to position a second marker on the peak of the third harmonic distortion product of the 280 MHz input signal. The response should be below the display line (>75 dB below the input signal level).

Performance Tests 2 - 51

15. Spurious Responses Test

Intermodulation

Distortion

SPECTRUM ANALYZER

ATTENUATORATTENUATOR

DIRECTIONAL

50 MHz LON

PASS FILTER

Figure 2-26. Intermodulation Distortion Test Setup

11.Connect equipment as shown in Figure 2-26.

12.Set the controls of the spectrum analyzer as follows:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . 29.5 MHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 MHz

REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -20 dBm

DISPLAY LINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OFF

13.On the synthesized sweeper, key in [cw 30 MHz, [POWER LEVEL], -4 dBm and use the ENTRY knob to position the peak of the displayed 30 MHz signal at the top CRT graticule line.

14.On the frequency synthesizer, key in [FREQUENCY) 29 MHz,

(AMPLITUDE) -4 dBm. Readjust the signal amplitude as necessary to position the peak of the displayed 29 MHz signal at the top CRT graticule line.

15. Set the controls of the spectrum analyzer as follows:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 MHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 Hz

16.On the spectrum analyzer, key in DISPLAY LINE (ENTER) -100 dBm, MARKER [PEAK SEARCH) to position a marker on the peak of the displayed 29 MHz signal.

17.On the frequency synthesizer, adjust the signal amplitude for a marker indication of -20.00 dBm.

18.On the spectrum analyzer, key in [CENTER FREQUENCY) 30 MHz, MARKER [PEAK SEARCH) to position a marker on the peak of the displayed 30 MHz signal.

19.On the synthesized sweeper, adjust the signal power level for a marker indication of -20.00 dBm.

2 - 5 2 P e r f o r m a n c e T e s t s

15. Spurious Responses Test

Note If unable to locate intermodulation distortion products, temporarily increase output power level of frequency synthesizer and synthesized sweeper by + 10 dB. Return the output power level of both

signal sources to the previous settings before making distortion measurements.

20. On the spectrum analyzer, key in MARKER [n),

[CENTER FREQUENCY) 31 MHz, MARKER [PEAK SEARCH) to position

a marker at the peak of the 31 MHz third-order intermodulation product. The response should be below the display line (GO dB below the input signals).

TO1 Distortion (1 MHz separation @ 30 MHz) dBm

21.On the spectrum analyzer, key in [CENTER FREQUENCY) 28 MHz, MARKER [PEAK SEARCH] to position a marker at the peak of the 28 MHz third-order intermodulation product. The response should be below the display line (>80 dB below the input signals).

TO1 Distortion (1 MHz separation @ 30 MHz) dBm

Q

2- 5 0

-6 0

-7 0

f2 - fl

S E C O N D

O R D E R

fl fz

S E C O N D

H A R M O N I C S

F R O M S I G N A L

GENERAToRS\

211 2f2

-

L

S E C O N D

T H I R DO R D E R

O R D E R

Figure 2-27. Intermodulation Distortion Products

22.On the frequency synthesizer, key in [FREQUENCY) 29.99 MHz.

23.On the spectrum analyzer, key in MARKER IOFF),

CCENTER FREQUENCY) 29.99 MHz, DISPLAY LINE [ENTER] -90 dBm,

MARKER (PEAK SEARCH).

Performance Tests 2 - 53

15. Spurious Responses Test

24.On the frequency synthesizer, readjust the signal amplitude as necessary to position the peak of the displayed 29.99 MHz signal at the top CRT graticule line.

25.On the spectrum analyzer, key in MARKER @,

(CENTER FREQUENCY) 30.01 MHz, MARKER (PEAK SEARCH) to position a second marker at the peak of the 30.01 MHz third-order intermodulation product. The response should be below the display line (>70 dB below the input signals).

TO1 Distortion (10 kHz separation @ 30 MHz) dBm

26.On the spectrum analyzer, key in [CENTER FREQUENCY) 29.98 MHz, MARKER [PEAK SEARCH) to position a second marker at the peak of the 29.98 MHz third-order intermodulation product. The response should be below the display line (>70 dB below the input signals).

TO1 Distortion (10 kHz separation @ 30 MHz) dBm

27.On the synthesized sweeper, press (POWER LEVEL] and decrease the amplitude of the 30 MHz signal by 13.0 dB from the current setting.

28.On the frequency synthesizer, key in [FREQUENCY] 29 MHz, (AMPLITUDE] and then decrease the amplitude of the 29 MHz signal by 13.0 dB from the current setting.

29.Set the controls of the spectrum analyzer as follows:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 MHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . ,500 Hz

REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -33 dBm

MARKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OFF

30.On the spectrum analyzer, key in DISPLAY LINE [ml -105 dBm, MARKER CPEAK SEARCH) to position a marker on the peak of the displayed 29 MHz signal.

31.On the frequency synthesizer, adjust the signal amplitude for a marker indication of -33.0 dBm.

32.On the spectrum analyzer, key in CCENTER FREQUENCY) 30 MHz, MARKER [PEAK SEARCH) to position a marker on the peak of the displayed 30 MHz signal.

33.On the synthesized sweeper, adjust the signal power level for a marker indication of -33.0 dBm (total signal power of -40 dBm at the input mixer with 10 dB of input attenuation).

34.On the spectrum analyzer, key in MARKER a,

[CENTER FREQUENCY) 1 MHZ, MARKER [PEAK SEARCH] to position

a second marker at the peak of the 1 MHz second-order intermodulation distortion product. The response should be below the display line (>75 dB below the total input power).

SO1 Distortion (1 MHz separation @ 30 MHz) dBm

2 - 5 4 P e r f o r m a n c e T e s t s

15. Spurious Responses Test

35.On the spectrum analyzer, key in [CENTER FREQUENCY] 59 MHz, MARKER [PEAK SEARCH) to position a second marker at the peak of the 59 MHz second-order intermodulation distortion product. The response should be below the display line (>75 dB below the total input power).

SO1 Distortion (1 MHz separation @ 30 MHz) dBm

Performance Tests 2 - 55

16. Residual FM

Test

Specification <3 Hz peak-to-peak in 110 s; frequency span ~100 kHz, resolution bandwidth 530 Hz, video bandwidth 530 Hz.

Description The spectrum analyzer CAL OUTPUT is used to supply a stable 20 MHz signal to the analyzer. The analyzer is tuned in zero span to a point on the 30 Hz bandwidth response for which the slope of the response is known from direct measurement. The residual FM is then slope detected over a 10 second interval, yielding a trace whose peak-to-peak excursion is proportional to the residual FM.

Equipment None Required

Procedure 1. Press (~N~TR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Press (RECALL) 8 and adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm ho.02 dB.

4.Press CRECALL) 9 and adjust FREQ ZERO for a maximum amplitude trace.

5.Set PREFERENCE LEVEL) to -10 dBm. Adjust FREQ ZERO counterclockwise until trace is at the center graticule line.

6.Set ~FREQUENCY SPAN) to 100 Hz. Press SWEEP CSINGLE) and wait for completion of the sweep.

7.Press MARKER Cm), and place marker 1 division above the center graticule line on the negative-going side of the trace. Press MARKER In] and set the movable marker 1 division below the center graticule line. See Figure 2-28.

2 - 5 6 P e r f o r m a n c e T e s t s

16. Residual FM Test

hr RF -I... L 1u

Figure 2-28. Bandwidth Filter Slope Measurement

8.Compute the detection slope of the 30 Hz filter between the markers by dividing the MARKER A amplitude by the MARKER A frequency:

filter slope = MARKER A amplitude/MARKER Afrequency = dB/Hz

9.Press SWEEP [CONT),(mj IOFF).

10.Change FREQUENCY SPAN] to 0 Hz. Readjust FREQ ZERO, if necessary, to position the trace at the center graticule line. The amplitude variations of the trace (see Figure 2-29) represent the analyzer residual FM.

P e r f o r m a n c e T e s t s 2-57

16. Residual FM Test

Figure 2-29. Slope Detected Residual FM

11.Press SWEEP CRINGLE) and wait for completion of the sweep.

12.Press MARKER [PEAK SEARCH_). Press DISPLAY LINE (m??? and position the display line at the lowest point on the trace.

Figure 2-30. Peak-to-Peak Amplitude Measurement

2 - 5 8 P e r f o r m a n c e T e s t s

16. Residual FM Test

13.Press MARKER Ia] and position movable marker at the lowest point on the trace (see Figure 2-30). Read the MARKER A amplitude from the display and record its absolute value.

14.Divide the peak-to-peak amplitude by the slope computed in step 8 to obtain the residual FM:

p-p amplitude/filter slope = residual FM

= residual FM

The residual FM should be less than 3 Hz.

15.Press ~NSTR PRESET].

16.Press Cm] 9 and adjust FREQ ZERO for a maximum amplitude trace.

Performance Tests 2 - 59

17. Line-Related

Sidebands Tests

Specification

Description

Equipment

Procedure

95 dB below the peak of a CW signal. Option $00: >75 dB below the peak of a CW signal.

The spectrally pure calibrator signal of the spectrum analyzer is applied to the analyzer input and the line related sidebands near the signal are measured.

None required

1.Press ~NSTR PRESET) on the analyzer. Connect CAL OUTPUT to

SIGNAL INPUT 2.

2.Press C-j 8 and adjust AMPTD CAL for a MARKER amplitude of -10.00 dBm f0.02 dB.

3.Press (~NSTR PRESET).

4.Key in the following analyzer settings:

5. Wait for completion of sweep, then press MARKER

[ P E A K SEARCH),(jj).

6.Press (SHIFT) (-1 G, SWEEP @???i7ZZ], 10 (j-/Iv to initiate video averaging of 10 sweeps. Wait for completion of sweeps.

7.Press MARKER (PEAK SEARCH],(~) and position movable marker at the peak of each line related sideband (120 Hz, 180 Hz, and 240 Hz for 60 Hz line frequency; 100 Hz, 150 Hz, and 200 Hz for 50 Hz line frequency, etc.). The MARKER A amplitude for each sideband should be c-85 dB (see Figure 2-31).

2-60 P e r f o r m a n c e T e s t s

17. Line-Related Sidebands Tests

Figure 2-31. Line Related Sidebands Measurement

O p t i o n 4 0 0 1. Press ~NSTR PRESET]. Connect CAL OUTPUT to SIGNAL INPUT 2.

2.Press (ml 8 and adjust AMPTD CAL for a MARKER amplitude of -10. 00 dBm ??? tO.02 dB.

3.Press ONSTR PRESET).

4.Key in the following analyzer settings:

6.Press (SHIFT) [VlDEo] G, SWEEP (-1, 10 cm/Iv to initiate video averaging of 10 sweeps. Wait for completion of sweeps.

7.Press MARKER SPEAK SEARCH],@ and position movable marker at the peak of each line related sideband (400 Hz, 800 Hz, and 1200 Hz). The MARKER A amplitude for each sideband should be c-75 dB.

Performance Tests 2 - 61

18. Calibrator

Amplitude

Accuracy Test

Related Adjustment 20 MHz Reference Adjustments

Specification -10 dBm f0.3 dB

Description The output level of the calibrator signal is measured with a power meter.

SPECTRUW ANILYZER

Figure 2-32. Calibrator Amplitude Accuracy Test Setup

Equipment Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 436A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A

Adapter, Type N (f) to BNC (m) . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0077

Procedure 1. Connect equipment as shown in Figure 2-32.

2.Measure output level of the CAL OUTPUT signal. The value should be -10.0 dBm ho.3 dB.

dBm

2 - 62 Performance Tests

19. Fast Sweep Time Accuracy Test (~20 ms)

19. Fast Sweep

Time Accuracy

Test (430 ms)

Related Adjustment None

Specification &lo% for sweep times 5100 seconds

Description The triangular wave output of a function generator is used to modulate a 500 MHz signal which is applied to the spectrum analyzer SIGNAL INPUT. The signal is demodulated in the zero span mode to display the triangular waveform. Sweep time accuracy for sweep times ~20 ms is tested by checking the spacing of the signal peaks on the displayed waveform.

SPECTRUM ANALYZER

SYNTHESIZED SWEEPER

Procedure 1. Connect equipment as shown in Figure 2-33.

2.Press QNSTR PRESET) on spectrum analyzer.

3.Key in analyzer settings as follows:

4.Set synthesized sweeper for an output frequency of 500 MHz and an output power level of -10 dBm.

Performance Tests 2 - 63

19.Fast Sweep Time Accuracy Test (~20 ms)

5.Press MARKER (PEAK SEARCHJ@~EFZF),~.

6.Set [FREQUENCY SPAN) to 0 Hz, (j-1 to 3 MHz, [VlDEoBW) to 3 MHz, and press TRIGGER Cm].

7.Set synthesized sweeper for an amplitude-modulated output.

8.Set function generator controls as follows:

9.Key in (SWEEP TIME] 5 ms and set function generator for a counter reading of 2.00 f0.02 kHz.

10.Adjust spectrum analyzer TRIGGER LEVEL to place a peak of the triangular waveform on the first graticule from the left edge of the CRT display as a reference. (Adjust function generator amplitude, if necessary, to provide a signal large enough to produce a stable display). The fifth peak from the reference should be within ~l~0.5 division of the sixth graticule from the left edge of the display (see Figure 2-34).

11.Using sweep times and function generator frequencies in

Table 2-18, check sweep time accuracy for sweep times ~20 ms by procedure of step 10.

Figure 2-34. Fast Sweep Time Measurement (~20 ms)

2 - 64 Performance Tests

19. Fast Sweep Time Accuracy Test (~20 ms)

Performance Tests 2 - 65

20. 1st LO Output Amplitude Test

Specification >+4 dBm from 2.0 GHz to 3.7 GHz

Description The power level at the 1ST LO OUTPUT connected is measured as the first L.O. is swept over its 2.0 GHz to 3.1 GHz range.

SPECTRUM ANALYZER

POWER METER

Figure 2-35. 1st LO Output Amplitude Test Setup

Equipment Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 436A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A

Procedure 1. Press (INSTR PRESET].

2.Set [SWEEP TIME) to 100 seconds.

3.Calibrate power meter and sensor. Connect equipment as shown in Figure 2-35.

4.Observe the meter indication as the analyzer makes a complete sweep. The indication should be > + 4 dBm across the full sweep range.

dBm

5. Replace 50 ohm terminator on 1ST LO OUTPUT.

2 - 6 6 P e r f o r m a n c e T e s t s

21. Frequency Reference Error Test

21. Frequency

Reference Error

Test

Related Adjustment Time Base Adjustment

Specification Aging Rate

<l x 10eg/day and ~2.5 x 10m7 year; attained after 30 days warmup from cold start at 25??C.

Temperature Stability

<7 x lo-??? 0??? to 5E9???C. Frequency is within 1 x lo-??? of final stabilized frequency within 30 minutes.

Description The frequency of the spectrum analyzer time base oscillator is measured directly using a frequency counter locked to a frequency reference which has an aging rate less than one-tenth that of the time base specification. After a 30 day warmup period, a frequency measurement is made. The analyzer is left undisturbed for a 24-hour period and a second reading is taken. The frequency change over this 24-hour period must be less than one part in 10???.

Note This test requires that the spectrum analyzer be turned on (not in STANDBY) for a period of 30 days to ensure that the frequency reference attains its aging rate. However, after aging rate is attained, the frequency reference typically attains aging rate again in 72 hours of operation after being off for a period not exceeding 24 hours.

Care must be taken not to disturb the spectrum analyzer during the 24-hour test interval, since the frequency reference is sensitive to shock and vibration. The frequency reference should remain within its attained aging rate if the instrument is left on, the instrument orientation with respect to the earth???s magnetic field is maintained, and the instrument does not sustain any mechanical shock. Frequency changes due to orientation with respect to the earth???s magnetic field and altitude changes will usually be nullified when the instrument

is returned to its original position. Frequency changes due to mechanical shock will usually appear as a fixed frequency error.

The frequency reference is also sensitive to temperature changes; for this reason the ambient temperature near the instrument at the first measurement time and the ambient temperature at the second measurement time should not differ by more than 1??C.

Placing the spectrum analyzer in STANDBY mode turns the instrument off while continuing to provide power for the frequency reference oven, helping to minimize warmup time. However, the frequency reference must be on to attain its aging rate.

Performance Tests 2 - 67

???lhble 2-19. Performance Tkst Record

Performance Tests 2-69

Tkst 1. Center

Frequency Readout

Accuracy Test

Step 8. Center Frequency Readout Error Test Record

2-70 Performance Tests

Test 2. Frequency Span Accuracy Test

???I&t 2. Frequency

Span Accuracy Test

Steps 7, 9, and 11. Wide Span Error

Step 12. Span Error

Note The specification in Table 2-4 was derived using the following formula:

For spans > 1 MHz, the spec is: >&[(.02)(A synth freq) + (.005)(span)]

For spans 5 1 MHz, the spec is: >&[(.05)(A synth freq) + (.005)(span)]

Performance Tests 2-71

Test 3. Sweep

Time Accuracy

Step 6. Sweep Time Accuracy, Sweep Times 220 ms

Step 12. Sweep Time Accuracy, Sweep Times 220 s

21

Step 19. Sweep Time Accuracy, Sweep Times 220 ms (Alternate Procedure)

2-72 Performance Tests

???I&t 4. Resolution

Bandwidth

Accuracy

Test 4. Resolution Bandwidth Accuracy

Performance Tests 2-73

Test 5. Resolution

Bandwidth

Selectivity

Steps 7, 8 and 9. Resolution Bandwidth Selectivity

2-74 Performance Tests

Test 6. Resolution Bandwidth Switching Uncertainty Test

lkst 6. Resolution Bandwidth Switching Uncertainty Test

Step 6. Bandwidth Switching Uncertainty

Performance Tests 2-75

Test 7. Input

Attenuator

Switching

Uncertainty Test

2-76 Performance Tests

Test 8. Frequency Response Test

Performance Tests 2-77

Test 9. RF Gain

Uncertainty Test

Step 6. 2nd LO Shift

Min Measured Max

2-78 Performance Tests

Test 10. IF Gain Uncertainty Test

Test 10. IF Gain

Uncertainty Test

Step 12. Step IF Gain Uncertainty, 10 dB Steps

Step 18. IF Gain Uncertainty, 2 dB Steps

Performance Tests 2-79

Test 10. IF Gain Uncertainty Test

Step 22. IF Gain Uncertainty, 0.1 dB Steps

2-80 Performance Tests

Step 24. Recorded deviations from Steps 18 and 22.

26.Sum of negative deviations of A, C, & D -0.6 dB

28.Sum of negative deviations of A, B, C, & D -1.0 dB

Performance Tests 2-81

YLkst 11. Log Scale

Switching

Uncertainty Tkst

Step 6. Log Scale Switching Uncertainty

SCALE MKR Amplitude

(dB/DIV) PW

1

2

5

10

Deviation Allowable

(W Deviation

(W

xto.5

hO.5

f0.5

2-82 Performance Tests

Test 12. Amplitude Fidelity Test

Test 12. Amplitude

Fidelity ???I&t

Step 6. Log Amplitude Fidelity

Step 14. Linear Amplitude Fidelity

Performance Tests 2-83

Test 13. Average

Noise Level Test

2-84 Performance Tests

Test 14. Residual Responses Test

Test 14. Residual

Responses Test

Step 11. Maximum Residual Response

Performance Tests 2-85

Tkst 15. Spurious

Responses Tkst

2-86 Performance Tests

Test 16. Residual FM Test

Test 16. Residual

FM Test

Step 14. Residual FM

IMinIMeasuredIrax]

Performance Tests 2-87

Tkst 17.

Line-Related

Sidebands Test

2-88 Performance Tests

Test 18. Calibrator Amplitude Accuracy Test

Test 18. Calibrator

Amplitude

Accuracy ???I&t

Step 2. CAL OUTPUT Amplitude

Performance Tests 2.89

Test 19. Fast

Sweep Time Accuracy Test (~20

ms)

Step 11. F&t Sweep Time Accuracy (~20 ms)

[SWEEP TIME) Function Generator Frequency

(kW

2.90 Performance Tests

Test 20. 1st LO Output Amplitude Test

Test 20. 1st LO Output Amplitude Test

Step 4. 1st LO Output Level

Performance Tests 2-91

Test 21. Frequency

Reference Error

Test

2-92 Performance Tests

3

Adjustments

Introduction

Warning

The procedures in this section are for the adjustment of the instrument???s electrical performance characteristics.

The procedures require access to the interior of the instrument and therefore should only be performed by qualified service personnel. Refer to Safety Considerations in this introduction.

1. Low Voltage Power Supply Adjustments . . . . . . . . . . . . . . . . . . . . . .3-10 2. High Voltage Adjustment (SN 3001A and Below) . . . . . . . . . . . . . 3-10 2. High Voltage Adjustment (SN 3004A and Above) . . . . . . . . . . . . .3-10 3. Preliminary Display Adjustment (SN 3001A and Below) . . . . . .3-10 3. Preliminary Display Adjustment (SN 3004A and Above) . . . . . 3-10 4. Final Display Adjustments(SN 3001A and Below) . . . . . . . . . . . . .3-10 4. Final Display Adjustments(SN 3004A and Above) . . . . . . . . . . . . 3-10 5. Log Amplifier Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 6. Video Processor Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 7. 3 MHz Bandwidth Filter Adjustments . . . . . . . . . . . . . . . . . . . . . . . . .3-10 8. 21.4 MHz Bandwidth Filter Adjustments . . . . . . . . . . . . . . . . . . . . . .3-10 9. 3 dB Bandwidth Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 10. Step Gain and 18.4 MHz Local Oscillator Adjustments . . . . . . 3-10 11. Down/Up Converter Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 12. Time Base Adjustment (SN 2840A and Below) . . . . . . . . . . . . . . 3-10 12. Time Base Adjustment (SN 2848A and Above) . . . . . . . . . . . . . . 3-10 13. 20 MHz Reference Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 14. 249 MHz Phase Lock Oscillator Adjustments . . . . . . . . . . . . . . . . 3-10 15. 275 MHz Phase Lock Oscillator Adjustments . . . . . . . . . . . . . . . . 3-10 16. Second IF Amplifier and Third Converter Adjustments . . . . . 3-10 17. Pilot Second IF Amplifier Adjustments . . . . . . . . . . . . . . . . . . . . . . 3-10 18. Frequency Control Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 19. Second Converter Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 20. 50 MHz Voltage-Tuned Oscillator Adjustments . . . . . . . . . . . . . . .3-10 21. Slope Compensation Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 22. Comb Generator Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 23. Down/Up Converter Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 24. Track and Hold Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-10 25. Digital Storage Display Adjustments . . . . . . . . . . . . . . . . . . . . . . . . .3-10

The adjustment procedures should not be performed as routine maintenance, but only when Performance Tests cannot meet specifications. Before attempting any adjustment, allow the instrument to warm up for one hour. ???lhble 3-1 is a cross reference of Function Adjusted to the related Adjustment procedure. Table 3-2 lists all adjustable components by name, reference designator, and function.

Adjustments 3-1

Safety

Considerations

Warning

Equipment

Required

Adjustment Tools

Although this instrument has been designed in accordance with international safety standards, this manual contains information, cautions, and warnings which must be followed to ensure safe operations and to retain the instrument in safe condition. Service and adjustments should be performed only by qualified service personnel.

Adjustments in this section are performed with power supplied to the instrument while protective covers are removed. There are voltages at many points in the instrument which can,

if contacted, cause personal injury. Be extremely careful. Adjustment should be performed only by trained service personnel.

Power is still applied to this instrument with the LINE switch in STANDBY. There is no OFF position on the LINE switch. Before removing or installing any assembly or printed circuit board, remove the power cord from the rear of both instruments and wait for the MAINS indicators (red LEDs) to go completely out.

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

Use a non-metallic tuning tool whenever possible.

The equipment required for the adjustment procedures is listed in ???lkble l-l, Recommended Test Equipment, at the beginning of this manual. If the test equipment recommended is not available, substitutions may be used if they meet the ???Critical Specifications???

listed in the table. The test setup used for an adjustment procedure is referenced in each procedure.

For adjustments requiring a non-metallic tuning tool, use fiber tuning tool HP Part Number 8710-0033. In situations not requiring non-metallic tuning tools, an ordinary small screwdriver or other suitable tool is sufficient. However, it is recommended that you use a non-metallic adjustment tool whenever possible. Never try to force

any adjustment control in the analyzer. This is especially critical when tuning variable slug-tuned inductors and variable capacitors.

3-2 Adjustments

???able 3-l. Adjustment Cross Reference

Factory-Selected

Components

Factory-selected components are identified with an asterisk (*) on the schematic diagram. For most components, the range of their values and functions are listed in Table 3-3, Factory- Selected Components. Part numbers for selected values are located in Table 3-4, HP Part Numbers of Standard Value Replacement Components.

Adjustments 3-3

Related

Adjustments

Location of lkst Points and Adjustments

Any adjustments which interact with, or are related to, other adjustments are indicated in the adjustments procedures. It is important that adjustments so noted are performed in the order indicated to ensure that the instrument meets specifications.

Illustrations showing the locations of assemblies containing adjustments, and the location of those adjustments within the assemblies, are contained within the adjustment procedures to which they apply. Major assembly and component location illustrations are located at the rear of this manual.

3-4 Adjustments

For Serial Prefix 3001A and below, see back of table for exceptions to AlA through AlA6.

Adjustments 3-5

???able 3-2. Adjustable Components (continued)

Adjustments 3-7

3-8 Adjustments

Adjustments 3-9

3-10 Adjustments

???lhble 3-2. Adjustable Components (continued)

Adjustments 3-11

???Ihble 3-2. Adjustable Components (continued)

3-12 Adjustments

???Ihble 3-3. Factory-Selected Components

Function of Component

Sets intensity level. Sets intensity level. Sets intensity level. Sets intensity level.

Compensates for feedthrough of INTG signal to Ul.

Compensates for feedthrough of INTG signal to Ull.

Compensates for DAC ladder resistance. Compensates for DAC ladder resistance.

Sets adjustment range of A4AlR36 FS Compensates for ON resistance of A4AlQ6

Sets adjustment range of LG20.

Adjusts log fidelity.

Log fidelity.

Adjusts overall linear gain.

Sets adjustment range of ATTEN.

Temperature compensation

Temperature compensation

Temperature compensation

Temperature compensation

Temperature compensation

Temperature compensation

Adjusts bandpass filter shape in wide bandwidths (> 100 kHz).

Sets adjustment range of CTR. Sets adjustment range of CTR. Log fidelity

Log fidelity Log fidelity Log fidelity Log fidelity Log fidelity

Sets adjustment range of LGlO. Sets adjustment range of AMPTD.

Adjustments 3-13

l???hble 3-3. Factory-Selected Components (continued)

3-14 Adjustments

Adjustments 3-15

3-16 Adjustments

Adjustments 3-17

???able 3-3. Factory-Selected Components (continued)

3-18 Adjustments

???able 3-3. Factory-Selected Components (continued)

Adjustments 3-19

???lkble 3-4. Standard Value Replacement Capacitors

rapaors

Value (pF) 1BP Fart Number CD Value (pF) ZP Fart Number s-

-

3-20 Adjustments

Adjustments 3-21

???Ihble 3-5.

Standard Value Replacement 0.125 Resistors (continued)

Type: Fixed-Film

Range: 10 to 464K Ohms

Wattage: 0.125 at 125??C

To1 e???an fl.O%

Value (0) BP Part Number co Value (!I) ElP Fart Number

-

3-22 Adjustments

Table 3-6. Standard Value Replacement 0.5 Resistors

Resistors

Type: Fixed-Film

Range: 10 to 1.47M Ohms

Wattage: 0.5 at 125???C

To1???ant 31.0%

EIP Fart Number 5 Value (fl) BP Part Number 56 Value (0)-

-

Adjustments 3-23

Ihble 3-6.

Standard Value Replacement 0.5 Resistors

(continued)

Type: Fixed-Film

Range: 10 to 1.47M Ohms

Wattage: 0.5 at 125??C

To1 e*an fl.O%

Value (0) EIP Fart Number CD Value (a) EIP Fart Number

-

3-24 Adjustments

1. Low-Voltage

Power Supply

Adjustments

Reference

1. Low-Voltage Power Supply Adjustments

IF-Display Section:

AlA f15 V Regulator

AlA + 120 V, +5.2 V Regulator (Serial Number Prefix 3004A and above)

AlA + 100 V, +5.2 V Regulator (Serial Number Prefix 3001A and below)

RF Section:

A24 Voltage Regulator

Description The + 15 V supply is adjusted for the IF-display Section, and the +20 V supply is adjusted for the RF Section. All other low-voltage supplies are measured to ensure that they are within tolerance.

SPECTRUM ANALYZER

DIGITAL VOLTMTER

ADAPTER

(+)

Equipment

Procedure

IF-Display Section

Note

Figure 3-l. Low-Voltage Power Supply Adjustments Setup

Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

1.Position the instrument on its right side with the IF-Display Section facing right, as shown in Figure 3-1. Remove the top cover of the IF-Display Section and the bottom cover of the RF Section.

2.Set the LINE switch to ON and press (Ip). Mains indicator AlABDSl (red LED) in the IF-Display Section should be lit. See Figure 3-2 and Figure 3-3 for the location of AlABDSl.

Use Figure 3-2 for IF-Display Sections with serial numbers 3001A and below. Use Figure 3-3 for IF-Display Sections with serial numbers 3004A and above.

3. Verify that the + 15 V indicator AlAGDSl (yellow LED) is lit.

Adjustments 3-25

1.Low-Voltage Power Supply Adjustments

4.Connect the DVM to AlA6TP3 on the IF-Display Section. DVM

indication should be + 15.000 fO.O1O V dc. If the voltage is out of tolerance, adjust AlA6R9 + 15 V ADJ for the specified voltage.

, AlA71P2

AlA6DS2

AlA6TP4 5

Figure 3-2.

IF-Display Section Low-Voltage Adjustments (SN 3001A and

Below)

A l A7DS2

AlA7TP3

A lA6DS2

AiA6TP4

t

Figure 3-3.

IF-Display Section Low-Voltage Adjustments (SN 3004A and

Above)

5.Verify that the -15 V indicator AlA6DS2 (yellow LED) is lit.

6.Connect the DVM to AlA6TP4. DVM indication should be

-15.000 f0.050 V dc. The -15 V supply is referenced to the + 15 V supply; therefore, if the -15 V supply is out of tolerance, a circuit malfunction is indicated.

3-26 Adjustments

Note

Note

1.Low-Voltage Power Supply Adjustments

7.Verify that the + 120 V indicator AlA7DS2 (yellow LED) is lit.

On IF-Display Sections serial prefixed 3001A and below, indicator AlA7DS2 is a + 100 V indicator.

8.Connect the DVM to AlA7TP3. DVM indication should be + 120.0 ~k3.0 V dc. The + 120 V supply is referenced to the + 15 V supply; therefore, if the + 120 V supply is out of tolerance, a circuit malfunction is indicated.

On IF-Display Sections serial prefixed 3001A and below, the DVM indication should be + 100.0 62.0 V de.

9.Verify that the +5.2 V indicator AlA7DSl (yellow LED) is lit.

10.Connect the DVM to AlA7TP2. DVM indication should be +5.200 ho.050 V dc. The +5.2 V supply is referenced to the + 15 V supply; therefore, if the +5.2 V supply is out of tolerance, a circuit malfunction is indicated.

RF Section 11. The +2OV indicator A24DS2 (yellow LED) should be lit. See Figure 3-4.

A24

V O L T A G EA24R60

R E G U L A T O R +2OV A D J

A24

Figure 3-4. Location of RF Section Low-Voltage Adjustments

12.Connect the DVM to A24TP3 with the ground lead to A24TPl. Adjust A24R60 +2OV ADJ for a DVM indication of +20.000 &O.OlO V dc.

13.The + 15V indicator A24DS4 (yellow LED) should be lit.

14.Connect the DVM to A24TP2. The DVM indication should be

+15.000 ho.050 V dc. The + 15V supply is referenced to the

+2OV supply, therefore, if the + 15V supply is out of tolerance, a circuit malfunction is indicated.

15.The +5V indicator A24DS5 (yellow LED) should be lit.

16.Connect the DVM to A24TP5. The DVM indication should be +5.230 f0.050 V dc. The +5V supply is referenced to the +2OV

Adjustments 3-27

1. Low-Voltage Power Supply Adjustments

supply, therefore, if the +5V supply is out of tolerance, a circuit malfunction is indicated.

17.The -5V indicator A24DS6 (yellow LED) should be lit.

18.Connect the DVM to A24TP7. The DVM indication should be -5.200 ho.050 V de. The -5V supply is referenced to the +2OV supply, therefore, if the -5V supply is out of tolerance, a circuit malfunction is indicated.

19.The -15V indicator A24DS3 (yellow LED) should be lit.

20.Connect the DVM to A24TP4. The DVM indication should be

-15.000 f0.050 V dc. The -15V supply is referenced to the + 20V supply, therefore, if the -15V supply is out of tolerance, a circuit malfunction is indicated.

3-28 Adjustments

2. High-Voltage

Adjustment (SN

3001A and Below)

Note

2. High-Voltage Adjustment (SN 3001A and Below)

This procedure is for IF-Display Sections with serial number prefixes 3001A and below. The procedure for serial prefixes 3004A and above is located immediately after this procedure.

Note This procedure should be performed whenever the AlAll High Voltage Multiplier, AlVl CRT, or AlA High Voltage Regulator Assembly is repaired or replaced.

Reference IF-Display Section:

AlA Z-Axis Amplifier

AlA High-Voltage Regulator

AlA f15 V Regulator

AlA + 100 V, +5.2 V Regulator

Description

Warning This procedure is intended for adjustment purposes only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -4000 V dc can be present on the AlA High Voltage assembly even when the ac line cord is disconnected. Do not attempt to remove the AlA High-Voltage Assembly from the instrument. Do not disconnect the CRT???s post-accelerator cable; the CRT can hold a + 18 kV dc charge for several days.

If for any reason the AlA High Voltage Assembly or the post accelerator cable must be removed, refer to ???Discharge Procedure for High Voltage and CRT??? at the end of this adjustment procedure.

A 1OOO:l divider probe is used to measure the CRT cathode voltage. First, the high-voltage probe is calibrated by comparing measurements of the + 100 V dc supply voltage with and without the probe. Any measurement error due to the use of the high-voltage probe is calculated into the adjustment specification of the CRT cathode voltage, which is adjusted with the AlA HV ADJUST control. When the CRT cathode voltage is properly adjusted, the CRT filament voltage will be +4.45 f0.04 V rms measured with CRT beam at cut-off, which is required for maximum CRT life. The filament voltage is referenced to the high-voltage cathode and can only be measured directly with special equipment.

Adjustments 3-29

2. High-Voltage Adjustment (SN 3001A and Below)

DIGITIZING

OSCILLOSCOPE

HI-VOLTAGE

SIGNAL ANALYZER

Figure 3-5. High Voltage Adjustment Setup

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 3456A DC High-Voltage Probe (1000: 1 divider) . . . . . . . . . . . . . . . . . . HP 34111A Display Adjustment PC Board (service accessory) . . . . . . .85662-60088 Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A 1O:l Divider Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10432A Function Generator (2 required) . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3312A

High-Voltage

Adjustment Procedure

Warning

In the following procedure, it is necessary to probe voltages which, if contacted, could cause serious personal injury. Use a nonmetallic alignment tool when making adjustments. Be extremely careful.

Warning Do not attempt to measure the CRT filament voltage directly. The filament voltage is referenced to the high-voltage cathode and can only be measured safely with a special high-voltage true-rms voltmeter and probe.

1.Set the spectrum analyzer???s LINE switch to STANDBY.

2.Remove the top cover from the IF-Display Section, and connect the equipment as shown in Figure 3-5 and described in the following steps.

3.Set the DVM to the 100 V range, and connect the DVM to AlA7TP3 (+ 100 V). Do not use the high-voltage probe. See

Figure 3-6 for the location of AlA7TP3.

3.30 A d j u s t m e n t s

Note

Warning

2. High-Voltage Adjustment (SN 3001A and Below)

The accuracy of the high-voltage probe is specified for a probe connected to a dc voltmeter with 10 M62 input resistance. HP 3456A and HP 3455A digital voltmeters have a 10 MQ input resistance on the 100 V and 1000 V ranges. All measurements in this procedure should be performed with the DVM manually set to the 100 V range (fOO.OOO on the HP 3456A display).

I

. AlA6R32

Figure 3-6. Location of High Voltage Adjustments

4.Set the LINE switch to ON. Set the front-panel INTENSITY control fully counterclockwise (CRT beam at cut-off) to prevent possible damage to the CRT.

5.Note the DVM indication at AlA7TP3.

DVM Indication:

6.Connect the high-voltage probe to the DVM. Connect the probe to AlA7TP3.

7.Note the DVM indication.

DVM Indication:

8.Divide the DVM indication in step 7 by the DVM indication in

step 5. This gives the calibration factor needed to compensate for high-voltage probe error.

Calibration Factor:

9.Disconnect the high-voltage probe from AlA7TP3. Set the LINE switch to STANDBY. Remove the ac line cord from both instrument sections.

The MAINS power-on indicator AlASDSl (red LED) should be completely off before proceeding with this procedure. See

Figure 3-6. The indicator will remain lit for several seconds after the ac line cord has been removed, and will go out slowly (the light becomes dimmer until it is completely out).

Adjustments 3-3 1

2. High-Voltage Adjustment (SN 3001A and Below)

12.Connect the high-voltage probe to AlA3TP3. See Figure 3-7 for the location of the test point.

AlA

H,gh V o l t a g e

R e g u lotor

Figure 3-7. Location of Label and Test Point

13.Reconnect ac line cords to both instrument sections. Set the LINE switch to ON.

14.Wait approximately 30 seconds for the dc regulator circuits to stabilize.

15.Adjust AlA6R32 HV ADJ for a DVM indication equal to the calibration factor (calculated in step 8) times the voltage labeled on the top of AlA High-Voltage Regulator (noted in step 11). See Figure 3-6 for the location of the adjustment.

V dc

EXAMPLE:

3-32 Adjustments

Focus and Intensity

Adjustments

2. High-Voltage Adjustment (SN 3001A and Below)

If the calibration factor calculated in step 8 is 0.00099, and AlA3Tl is labeled for -3875 V, then adjust AlA6R32 HV ADJ for a DVM indication of:

0.00099 x (-3875 V) = -3.836 V dc

16.With the front-panel INTENSITY control fully counterclockwise, wait approximately 30 minutes to allow the high-voltage supply to stabilize and the CRT to normalize. This sofl turn-on will extend CRT life expectancy, particularly if a new CRT has just been installed.

17.Readjust AlA6R32 HV ADJ for a DVM indication equal to the voltage determined in step 15.

18.If a new CRT has just been installed do the following:

a.Set the front-panel INTENSITY control so the CRT trace is barely visible.

b.Wait an additional 30 minutes for the CRT to normalize.

c.Readjust AlA6R32 HV ADJ for a DVM indication equal to the voltage determined in step 15.

19.Set the LINE switch to STANDBY. Remove the ac line cord from each instrument section.

20.Wait at least one minute for the MAINS power-on indicator AlA8DSl (red LED) to go out completely before proceeding.

21.Disconnect the high-voltage probe from AlA3TP3.

22.Remove the A3A2 Intensity Control Assembly from the IF-Display Section and install in its place the Display Adjustment Board,

HP part number 85662-60088. Set the switch on the Display Adjustment Board in the ???down??? position. (This applies approximately +2.7 V dc to the front-panel INTENSITY control.)

23.Connect a calibrated 1O:l divider probe to the oscilloscope Channel 1 input.

24.On the oscilloscope, press (RECALL) (CLEAR) to perform a soft reset.

25.On the oscilloscope, press CCHAN], more preset probe , select channel 1, and use the front-panel knob to select a 1O:l probe.

26.Set the oscilloscope controls as follows:

Press [CHAN):

Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .lO.OV/div offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..6O.OOOOV coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..dc

Press @%KiZi@:

time scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..50~s/div Press ITRIG):

EDGE TRIGGER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . auto, edge source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l level . . . . . . . . . . . . . . . . . . . . . . . . . .75.0000 V, rising edge

Press [DISPLAY):

connect dots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..on

Adjustments 3-33

2.High-Voltage Adjustment (SN 3001A and Below)

27.On the oscilloscope press [SHOW].

28.Connect the oscilloscope channel 1 probe to AlA3TP5 using a long probe extension. See Figure 3-7 for the location of AlA3TP5.

29.Reconnect the ac line cords to each instrument section. Adjust the front-panel INTENSITY control fully counter-clockwise, and then set the LINE switch to ON (the INSTR CHECK I LED will light.)

30.Wait approximately 30 seconds for the dc regulator circuits to stabilize again.

31.With the front-panel INTENSITY control fully counter clockwise, adjust AlA2R35 INT LIMIT (clockwise) until a spot is just visible in the lower left corner of the CRT. See Figure 3-8 for the location of the adjustment.

Note The AlA2R35 INT LIMIT adjustment compensates for the variation in beam cut-off voltage of different CRTs and indirectly sets the maximum beam intensity. AlA2R35 INT LIMIT should have enough range to turn the CRT spot on and off. If the spot is always on, decrease the value of AlA2R9. If the spot is always off, increase the value of AlA2R9. Refer to Table 3-3 for the acceptable range of values, and to Table 3-4 for HP part numbers. Refer to Figure 3-8 for the location of AlA2R9.

Figure 3-8. Location of AlA Components

32.Using a non-metallic alignment tool, center the front panel FOCUS control and adjust AlA2R36 ASTIG and AlA3R14 FOCUS LIMIT for a sharp, focused dot on the CRT display.

33.Adjust AlA2R35 INT LIMIT until the dot just disappears.

3-34 Adjustments

2.High-Voltage Adjustment (SN 3001A and Below)

34.On the oscilloscope, adjust the channel 1 offset voltage as

necessary to measure the peak-to-peak CRT cut-off voltage, V,,, at AlA3TP5. See Figure 3-9. This peak-to-peak voltage should be between 45-75 V,.,. Note this voltage for use in step 39.

1 1 0 . 0 V/div offset: 6 0 . 0 0 v

10.00 : 1 dc

1 f 7 5 . 0 0 v

Figure 3-9. CRT Cut-Off Voltage

35.Connect a separate function generator to each of the X and Y inputs of the Display Adjustment Board, as shown in Figure 3-5.

Set the function generators as follows:

36.Adjust AlA2R35 INT LIMIT clockwise until the display is just visible.

37.Adjust AlA4R7 POS, AlA5R7 POS, and if necessary the function generator de offsets for a full-screen illumination.

38.Set the front-panel INTENSITY control fully counter-clockwise, and, if it is not sealed, adjust AlA2R5 INT GAIN fully clockwise. Adjust AlA2R35 INT LIMIT just below the threshold at which the display illumination becomes visible.

Adjustments 3-35

2.High-Voltage Adjustment (SN 3001A and Below)

39.Slowly adjust the front-panel INTENSITY control through its entire range while monitoring the peak-to-peak voltage at AlA3TP5. As the INTENSITY control is turned clockwise, the peak-to-peak voltage at AlA3TP5 will drop. To prevent long-term CRT damage, this voltage should not drop below (V,, - 5O)V,., or 12 VP-,,, whichever is greater. See Figure 3-10. (The value of V,, was recorded in step 34.)

If the front-panel INTENSITY control cannot be set fully clockwise without dropping below this minimum peak-to-peak voltage, then perform the following:

a.Set the INTENSITY control fully counter clockwise.

b.Set the LINE switch to STANDBY.

c.Increase the value of AlA2R9.

d.Return to step 34.

Note Maximum CRT life expectancy is obtained when the peak-to-peak voltage at AlA3TP5 is as large as possible with the INTENSITY control set fully clockwise. The display illumination must fully disappear with the INTENSITY control set fully counter clockwise.

5 0 . 0 uS/dlv

1 f 85.00 v

Figure 3-10. Waveform at AlA3TP5

40.Replace the cover on the AlA High-Voltage Regulator Assembly.

41.The High-Voltage Adjustment is completed. If an AlA2, AlA4, or AlA assembly has been repaired or replaced, perform adjustment procedure 3, ???Preliminary Display Adjustment (SN 3001A and Below)???, and then adjustment procedure 4, ???Final Display Adjustments (SN 3001A and Below)???. If the AlA2,

3-36 Adjustments

Discharge Procedure for High Voltage and

CRT

Warning

2. High-Voltage Adjustment (SN 3001A and Below)

AlA4, and AlA assemblies function properly and do not require compensation, proceed directly to adjustment procedure 4, ???Final Display Adjustments (SN 3001A and Below)???.

The adjustment procedures in this manual do not require the removal or discharge of the AlA High-Voltage Regulator or CRT assemblies. However, if for any reason the AlA High Voltage Regulator Assembly or the post-accelerator cable must be removed, the following procedure ensures the proper safety.

This procedure should be performed by qualified personnel only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -4000 V dc is present on the AlA High-Voltage Regulator assembly even when the ac line cord is disconnected. The CRT can hold a + 18 kV dc charge

for several days if the post-accelerator cable is improperly disconnected.

Warning Do not handle the AlA High-Voltage Regulator Assembly or AlAll High-Voltage Multiplier until the following high-voltage discharge procedure has been performed.

1.Set the spectrum analyzer???s LINE switch to STANDBY, remove the ac line cords, and remove the AlA High Voltage Regulator safety cover.

Warning With the ac power cord disconnected, voltages are still present which, if contacted, could cause serious personal injury.

Adjustments 3-37

2.High-Voltage Adjustment (SN 3001A and Below)

5.While holding the insulated handle of the screwdriver, touch the

grounded blade to the following connections:

a.Both brown wires going to the rear of the CRT from AlA via cable harness W21.

b.The yellow, blue, and orange wires in the same cable as ???a. ??? above.

c.The top lead of each of the 11 large vertical capacitors on the AlA High-Voltage Regulator Assembly.

6.Connect the jumper wire from chassis ground to the black wire coming from the AlAll High-Voltage Multiplier at the wire???s connection to AlA3Tl.

AlA

H i g h V o l t a g e

,T 1

AlA3TlAIA3

Figure 3-l 1. Discharging the CRT Post-Accelerator Cable

7.Remove all jumper wires. The AlA High-Voltage Regulator, AlAll High-Voltage Multiplier, and AlVl CRT assemblies should now be discharged.

8.A small bracket and screw secure the AlA High-Voltage Regulator Assembly to the AlAlO Display Motherboard Assembly. The bottom cover of the IF-Display Section must be removed to gain access to this screw prior to removal of the AlA High-Voltage Regulator Assembly.

3-38 Adjustments

2. High-Voltage

Adjustment (SN

3004A and Above)

Note

2. High-Voltage Adjustment (SN 3004A and Above)

This procedure is for IF-Display Sections with serial number prefixes 3004A and above. The procedure for serial prefixes 3001A and below is located immediately before this procedure.

Note

Reference

This procedure should be performed whenever the AlVl CRT or AlA High Voltage Regulator Assembly is repaired or replaced.

IF-Display Section:

A lA2 Z-Axis Amplifier

AlA High-Voltage Regulator

AlA &15 V Regulator

AlA + 120 V, +5.2 V Regulator

Description

Warning This procedure is intended for adjustment purposes only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -2400 V dc can be present on the AlA High Voltage Regulator Assembly even when the ac line cord is disconnected. Do not attempt to remove the AlA High-Voltage Regulator Assembly from the instrument. Do not disconnect the CRT???s post-accelerator cable; the CRT can hold a + 9500 V dc charge for several days.

If for any reason the AlA High Voltage Assembly or the post accelerator cable must be removed, refer to ???Discharge Procedure for High Voltage and CRT??? at the end of this adjustment procedure.

A 1OOO:l divider probe is used to measure the CRT cathode voltage. First, the high-voltage probe is calibrated by comparing measurements of the + 120 V dc supply voltage with and without the probe. Any measurement error due to the use of the high-voltage probe is calculated into the adjustment specification of the CRT cathode voltage, which is adjusted with the AlA HV ADJUST control. When the CRT cathode voltage is properly adjusted, the CRT filament voltage will be +6.00 kO.05 V rms measured with CRT beam at cut-off, which is required for maximum CRT life. The filament voltage is referenced to the high-voltage cathode and can only be measured directly with special equipment.

Adjustments 3-39

2. High-Voltage Adjustment (SN 3004A and Above)

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 3456A DC High-Voltage Probe (1000: 1 divider) . . . . . . . . . . . . . . . . . . HP 34lllA

High-Voltage

Adjustment Procedure

Warning In the following procedure, it is necessary to probe voltages which, if contacted, could cause serious personal injury. Use a nonmetallic alignment tool when making adjustments. Be extremely careful.

Warning Do not attempt to measure the CRT filament voltage directly. The filament voltage is referenced to the high-voltage cathode and can only be measured safely with a special high-voltage true-rms voltmeter and probe.

1.Set the spectrum analyzer???s LINE switch to STANDBY.

2.Remove the top cover from the IF-Display Section and connect the equipment as shown in Figure 3- 12.

SPECTRUM ANALYZER

Figure 3-12. High Voltage Adjustment Setup

3.Set the DVM to the 1OOV range, and connect the DVM to AlA7TP3 (+ 120V) without the high-voltage probe. See Figure 3-13.

Note The accuracy of the high-voltage probe is specified for a probe connected to a de voltmeter with 10 MO input resistance. HP 3456A and HP 3455A digital voltmeters have a 10 MQ input resistance on the 100 V and 1000 V ranges. All measurements in this procedure should be performed with the DVM manually set to the 100 V range (&OO.OOO on the HP 3456A display).

3-40 Adjustments

2. High-Voltage Adjustment (SN 3004A and Above)

/ AlABOSl

- AlA7TP3

AlA H I G H

V O L T A G E

/ R E G U L A T O R

- AlA6R103

Figure 3-13. Location of High Voltage Adjustments

4.Set the LINE switch to ON. Set the front-panel INTENSITY control fully counterclockwise (CRT beam at cut-off) to prevent possible damage to the CRT.

5.Note the DVM indication at AlA7TP3.

DVM Indication:

6.Connect the high-voltage probe to the DVM, and connect the probe to AlA7TP3.

7.Note the DVM indication.

DVM Indication:

8.Divide the DVM indication in step 7 by the DVM indication in

step 5. This gives the calibration factor needed to compensate for high-voltage probe error.

Calibration Factor:

9.Disconnect the high-voltage probe from AlA7TP3. Set the LINE switch to STANDBY. Remove the ac line cord from both instrument sections.

Warning The MAINS power-on indicator AlASDSl (red LED) should be completely off before proceeding with this procedure. See

Figure 3-13 The indicator will remain lit for several seconds after the ac line cord has been removed, and will go out slowly (the light becomes dimmer until it is completely out).

Adjustments 3-41

2.High-Voltage Adjustment (SN 3004A and Above)

11.Remove the protective cover from the AlA High-Voltage Regulator Assembly. A label should be visible on the AlA3Al High Voltage Assembly. (AlASAl is mounted on the

non-component side of the High-Voltage Regulator Assembly as shown in Figure 3-14.) Record the voltage listed on the label for

use in step 15. In cases where more than one voltage is listed on this label, record the value which is closest to -2400 Vdc.

V dc

Warning With power supplied to the instrument, AlA3TP2A is at a voltage level of approximately -2400 V dc. Be extremely careful.

12.Connect the high-voltage probe to AlA3TP2A. See Figure 3-14 for the location of the test point.

AlA3TP2A

Figure 3-14. Location of AlA Label and Test Point

13.Reconnect ac line cords to both instrument sections. Set the LINE switch to ON.

14.Wait approximately 30 seconds for the de regulator circuits to stabilize.

15.Adjust AlA6R103 HV ADJ for a DVM indication equal to the calibration factor (calculated in step 8) times the voltage labeled on the top of the AlA3Al High-Voltage Assembly (noted in step 11). See Figure 3-13 for the location of the adjustment.

V dc

EXAMPLE:

If the calibration factor calculated in step 8 is 0.00099, and AlASAl is labeled for -2400 V, then adjust AlA6R103 HV ADJ for a DVM indication of:

0.00099 x (-2400 V) = -2.376 V dc

3-42 Adjustments

Discharge Procedure for High Voltage and

CRT

Warning

Warning

2.High-Voltage Adjustment (SN 3004A and Above)

16.With the front-panel INTENSITY control fully counter clockwise, wait approximately 10 minutes to allow the high-voltage supply to stabilize and the CRT to normalize. This sofl turn-on will extend CRT life expectancy, particularly if a new CRT has just been installed.

17.Readjust AlA6R103 HV ADJ for a DVM indication equal to the voltage determined in step 15.

18.If a new CRT has just been installed do the following:

a.Set the front-panel INTENSITY control so the CRT trace is barely visible.

b.Wait an additional 30 minutes for the CRT to normalize.

c.Readjust AlA6R103 HV ADJ for a DVM indication equal to the voltage determined in step 15.

19.Set the LINE switch to STANDBY. Remove the ac line cord from each instrument section.

20.Wait at least one minute for the MAINS power-on indicator AlASDSl (red LED) to go out completely before proceeding.

21.Disconnect the high-voltage probe from AlA3TP2A.

22.Replace the cover on the AlA High-Voltage Regulator Assembly.

23.The High-Voltage adjustments are now completed. If the AlA assembly has been repaired or replaced, perform adjustment procedure 3, ???Preliminary Display Adjustment (SN 3004A and Above)???, and then adjustment procedure 4, ???Final Display Adjustments (SN 3004A and Above)???. If the AlA assembly functions properly and does not require compensation, proceed directly to adjustment procedure 4, ???Final Display Adjustments (SN 3004A and Above)???.

The High-Voltage Adjustment procedure does not require the removal or discharge of the Al A3 High-Voltage Regulator or AlVl CRT assemblies. However, if for any reason the AlA High Voltage Regulator Assembly, the CRT, or the CRT post-accelerator cable must be removed, perform the following procedure to ensure proper safety.

This procedure should be performed by qualified personnel only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -2400 V dc can be present on the AlA High-Voltage Regulator assembly even when the ac line cord is disconnected. The CRT can hold a + 9500 V dc charge

for several days if the post-accelerator cable is improperly disconnected.

1. Remove the ac line cord from both instrument sections.

With the ac power cords disconnected, voltages can still be present which, if contacted, could cause serious personal injury.

2.Obtain an electrician???s screwdriver which has a thin blade at least eight inches long. The handle of the screwdriver must be made of an insulating material.

Adjustments 3-43

2.High-Voltage Adjustment (SN 3004A and Above)

3.Connect one end of a jumper wire (made of insulated wire and

two alligator clips) to the blade of the screwdriver. Connect the other end of the jumper wire to the metal chassis of the IF Display Section. This grounds the screwdriver.

4.Slide the screwdriver???s blade between the CRT and the sheet metal as shown in Figure 3-15. Gently work the tip of the screwdriver under the post-accelerator cable???s rubber shroud. Make sure that the screwdriver???s tip touches the connection between the post accelerator cable and the CRT. You should hear a cracking sound when the cable discharges.

5.Remove the cover from the AlA High-Voltage Regulator assembly.

6.Touch the screwdriver???s tip to the top lead of each of the 11 large vertical capacitors on the AlA High-Voltage Regulator assembly.

7.The AlA High-Voltage Regulator and AlVl CRT assemblies should now be discharged.

G r o u n d i n g

W i r e

Figure 3-15. Discharging the CRT Post-Accelerator Cable

Note A small bracket and screw secure the AlA High-Voltage Regulator Assembly to the AlAlO Display Motherboard Assembly. The bottom cover of the IF-Display Section must be removed to gain access to this screw prior to removal of the AlA High-Voltage Regulator Assembly.

3-44 Adjustments

3. Preliminary

Display

Adjustments (SN

3001A and Below)

Reference

Note

Note

3. Preliminary Display Adjustments (SN 3001A and Below)

AlAl Keyboard

AlA Z-Axis Amplifier

A1 A4 X-Deflection Amplifier

AlA Y-Deflection Amplifier

Adjustment 2, ???High-Voltage Adjustment,??? should be performed before performing the following adjustment procedure.

Perform this adjustment only if components have been replaced on the AlA Z-Axis Amplifier, AlA X-Deflection Amplifier, or AlA Y Deflection Amplifier Assemblies. Components AlA2R22 HF GAIN, AlABClO, AlA4R28 HF GAIN, AlA4Cl0, AlA4Cl1, AlA5R28 HF GAIN, AlA5Cl0, and AlA5Cll are factory adjusted and normally do not require readjustment.

Equipment Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A Pulse/Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8116A 1O:l Divider Probe, 10 MW7.5 pF (2 required) . . . . . . . . . . . HP 10432A Display Adjustment PC Board (setice accessory] . . . . . . .85662-60088 Termination, BNC 500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11593A

Adjustments 3-45

3. Preliminary Display Adjustments (SN 3001A and Below)

Procedure

X and Y Deflection

Amplifier Pulse

Response Adjustments

Note

1.Connect a 10:1 (10 MQ) divider probe to the oscilloscope???s channel

1input and a 10: 1 divider probe to the channel 4 input.

2.On the oscilloscope, press CRECALL) [ml to perform a soft reset.

3.On the oscilloscope, press [CHAN] more preset probe , select channel 1, and use the front-panel knob to select a 1O:l probe.

4.Select channel 4, and use the front-panel knob to select a 1O:l probe.

5.Press @iYGiJ

6.Connect the channel 1 probe to the oscilloscope???s rear panel PROBE COMPENSATION AC CALIBRATOR OUTPUT connector. Press [AUTO- SCALEJ Adjust the channel 1 probe for an optimum square wave display on the oscilloscope.

7.Connect the channel 4 probe to the oscilloscope???s rear panel PROBE COMPENSATION AC CALIBRATOR OUTPUT connector. Press LAUTO- SCALE_). Adjust the channel 4 probe for an optimum square wave display on the oscilloscope.

Each probe is now compensated for the oscilloscope input to which it is connected. Do not interchange probes without recompensating.

8.Connect the channel 1 1O:l divider probe to AlA4E1,and the channel 4 probe to AlA4E2, as shown in Figure 3-16. Connect the probe ground leads to chassis ground. See Figure 3-17 and Figure 3-18 for the location of the assemblies and test points.

SOQ TEPMNATIC+

PULSE/FUNCTION

GENERATOR

Figure 3-16. Preliminary Display Adjustments Setup

9.Remove the cover over A3 Digital Storage Section and remove A3A2 Intensity Control Assembly. Insert the Display Adjustment PC board (HP part number 85662-60088) into the A3A2 slot. See Figure 3-17 for the location of the A3A2 assembly.

3-46 Adjustments

3. Preliminary Display Adjustments (SN 3001A and Below)

A1A5,

AlA4-

AlA2???

- A3A2

Figure 3-17. Location of AlA2, AlA4, AlA5, and A3A2

~000uu000000u00ur

Figure 3-18. AlA2, AlA4, and AlA Adjustment Locations

10. Set the Pulse/Function Generator controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 kHz

Width(WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...250 ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.00 V

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,000 mV

Il. Connect the output of the Pulse/Function Generator to Jl (X input) on the Display Adjustment PC board in the A3A2 slot as shown in Figure 3-16.

Note The Pulse/Function Generator???s output must be terminated with 50 ohms. Use a BNC tee, a 500 termination, and a BNC female to SMB female adapter. Install the 500 termination as close to the Display Adjustment PC Board as possible.

Adjustments 3-47

3.Preliminary Display Adjustments (SN 3001A and Below)

16.Three waveforms should be displayed on the oscilloscope, as shown in Figure 3-20. The lower composite waveform represents the combined X deflection voltage applied to the CRT. Use the

oscilloscope???s front-panel knob to adjust waveform fl sensitivity for approximately 8 vertical divisions.

r e m o t e l i s t e n

:

Figure 3-20. Composite X Deflection Waveform

17.Adjust AlA4R28 HF GAIN, AlA4Cl0, and AlA4Cll for minimum overshoot and minimum rise and fall times of the composite X deflection waveform.

Note Always adjust AlA4ClO and AlA4Cll in approximately equal amounts. Do not adjust one to its minimum value and the other to its maximum value.

18.Use the oscilloscope Intnv) markers to measure the risetime, falltime, and percent overshoot of the composite X defection waveform. Rise and fall times should both be less than approximately 65 ns between the 10% and 90% points on the waveform. Overshoot should be less than 3% (approximately 0.25 divisions). See Figure 3-2 1.

O V E R S H O O T

O V E R S H O O T

Figure 3-2 1.

Rise and Fall Times and Overshoot Adjustment Waveform

Adjustments 3-49

3.Preliminary Display Adjustments (SN 3001A and Below)

19.Connect the oscilloscope???s channel 1 probe to AlA5El and the channel 4 probe to AlA5E2. See Figure 3-18 for the location of the test points. Connect the output of the pulse/function generator to 52 (Y input) on the Display Adjustment PC board in the A3A2 slot.

20.The Y Deflection Amplifier is identical to the X Deflection Amplifier. Repeat steps 12 through 18 for the Y Deflection Amplifier using R7, R27, R28, ClO, and Cl1 respectively.

Pulse Response of Control Gate Z Amplifier to BLANK Input

21.Disconnect the oscilloscope channel 4 probe from the spectrum analyzer. Connect the oscilloscope channel 1 probe to AlA2TP2, and connect the probe???s ground lead to chassis ground.

22.On the oscilloscope, press [RECALL) (CLEAR) to perform a soft reset.

2% Press (TiTiiQ CHANNEL 1 on, more preset probe , and use the

front-panel knob to set the probe to 10.00: 1. Press more .

24. Set the oscilloscope controls as follows:

Press (CHAN):

amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.0 V/div offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...25.0000 V

Press [TlMEBASEI):

time scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..50.0ns/div delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125.000 ns

Press ITRIG]:

level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.00000 V c

Press (-1:

connect dots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..on Press @ii??@.

25.Connect the output of the Pulse/Function Generator to 53 (Z input) on the Display Adjustment PC Board in the A3A2 slot. Set the board???s switch to the down position.

Note The pulse/function generator???s output must be terminated with 50 ohms. Use a BNC tee, a 5062 termination, and a BNC female to SMB female adapter. Install the 500 termination as close to the Display Adjustment PC Board as possible.

26. Set the pulse/function generator???s controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,200 kHz

Width(WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..250ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.OOV

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.OOV

27.Set the spectrum analyzer???s front-panel INTENSITY control fully clockwise. Note the display on the oscilloscope. The pulse should be >55V peak-to-peak.

3-50 Adjustments

3.Preliminary Display Adjustments (SN 3001A and Below)

28.Set the oscilloscope controls as follows:

Press @iK]:

Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.25 V/div

Press @iZZQ.

29.Adjust AlA4R7 X POS and AlA5R7 Y POS to either extreme to position the CRT beam off-screen (to prevent possible damage to the CRT phosphor). If it is not sealed, adjust AlA2R5 INT GAIN fully clockwise.

30.Adjust the spectrum analyzer???s front-panel INTENSITY control for 50V peak-to-peak (8 divisions) as indicated on the oscilloscope. See Figure 3-22.

18 . 0 0 V/div offset: 4 5 . 0 0 v

10.00 : I dc

1 2 5 . 0 0 0 ns3 7 5 . 0 0 0 ns 5 0 . 0 ns/dlv

1 f 50.00 v

Figure 3-22. 5OV,, Signal

31.Adjust AlA2R22 HF GAIN and AIABCIO for minimum overshoot on rise and minimum rise and fall times of the pulse waveform.

32.Use the oscilloscope [ml markers to measure the risetime, falltime, and percent overshoot of the pulse waveform. Rise and falltimes should be less than 50 ns and 90 ns respectively. Overshoot on the rise should be less than 5% (approximately 0.4 divisions).

33.Set the spectrum analyzer???s LINE switch to STANDBY, and center potentiometers AlA4R7 X POSN and AlA5R7 Y POSN.

34.Disconnect the oscilloscope channel 1 probe from the spectrum analyzer. Remove the Display Adjustment PC board from the A3A2 slot, and reinstall the A3A2 Intensity Control Assembly. Replace the A3 Section cover and cables.

35.Perform Adjustment Procedure 4, Final Display Adjustment (SN 3001A and Below).

Adjustments 3-51

3. Preliminary

Display

Adjustments (SN

3004A and Above)

Reference

Note

Note

AlAl Keyboard

Al A2 X, Y, Z Axis Amplifier

Adjustment Procedure 2, ???High-Voltage Adjustment,??? should be performed before performing the following adjustment procedure.

Perform this adjustment only if components have been replaced on the AlA X, Y, Z Axis Amplifier Assembly. Components R117, R217, R308, C104, C109, C204, C209, and C307 are factory adjusted and normally do not require readjustment. Components affecting these adjustments are located in function blocks F, H, M, N, 0, P, R, and S of the AlA X, Y, Z Axis Amplifier Assembly schematic diagram.

Description

Caution

The X, Y, Z Axis Amplifier Assembly is adjusted to compensate the CRT drive circuits for proper horizontal and vertical characteristics. These preliminary adjustments are necessary only after replacement or repair of the AlA X, Y, Z Axis Amplifier Assembly). For routine maintenance, CRT replacement, or minor repairs, only Adjustment Procedure 4, ???Final Display Adjustments,??? needs to be performed.

Be sure not to allow a fixed spot of high intensity to remain on the spectrum analyzer CRT. A high intensity spot may permanently damage the CRT???s phosphor coating. Monitor the CRT closely during the following adjustment procedures. If a spot occurs, move it off-screen by adjusting either the front-panel INTENSITY control, or the horizontal or vertical deflection position controls.

Equipment Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A Pulse/Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8116A

10:1 Divider Probe, 10 MW7.5 pF, (2 required) . . . . . . . . . . . HP 10432A Display Adjustment PC Board (service accessory) . . . . . . .85662-60088 Termination, BNC 500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 11593A

Adapters:

Adapter, BNC(f) to SMB(f) . . . . . . . . . . . . . . . . . . . . . . . .1250-1236 Adapter, BNC tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1250-0781

3-52 Adjustments

Procedure

X and Y Deflection

Amplifier Pulse

Response Adjustments

Note

3.Preliminary Display Adjustments (SN 3004A and Above)

1.Connect a 1O:l (10 MQ) divider probe to the oscilloscope???s channel

1input and a 1O:l divider probe to the channel 4 input.

2.On the oscilloscope, press (RECALL) (CLEARI) to perform a soft reset.

3.On the oscilloscope, press (CHAN) more preset probe , select channel 1, and use the front-panel knob to select a 10: 1 probe.

4.Select channel 4, and use the front-panel knob to select a IO:1 probe.

5.Press ml.

6.Connect the channel 1 probe to the oscilloscope???s rear panel PROBE COMPENSATION AC CALIBRATOR OUTPUT connector. Press CAUTO- SCALE). Adjust the channel 1 probe for an optimum square wave display on the oscilloscope.

7.Connect the channel 4 probe to the oscilloscope???s rear panel PROBE COMPENSATION AC CALIBRATOR OUTPUT connector. Press [AUTO- SCALE]. Adjust the channel 4 probe for an optimum square wave display on the oscilloscope.

Each probe is now compensated for the oscilloscope input to which it is connected. Do not interchange probes without recompensating.

8.Connect the channel 1 IO:1 divider probe to AlA2TP204, and the channel 4 probe to AlA2TP205, as shown in Figure 3-23. Connect the probe ground leads to AlA2TP106. See Figure 3-24 and Figure 3-25 for the location of the assemblies and test points.

5On TERkllNATlON W

Figure 3-23. Preliminary Display Adjustments Setup

9.Remove the cover over A3 Digital Storage Section and remove A3A2 Intensity Control Assembly. Insert the Display Adjustment PC board (HP part number 85662-60088) into the A3A2 slot. See Figure 3-24 for the location of the A3A2 assembly.

Adjustments 3-53

3. Preliminary Display Adjustments (SN 3004A and Above)

AlA

A3A2

A3Al

Figure 3-24. Location of AlA and A3A2

Figure 3-25. AlA Adjustment Locations

10. Set the Pulse/Function Generator controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,200 kHz

Width(WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...250 ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.00 V

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .O.OOO mV

11.Connect the output of the Pulse/Function Generator to Jl (X input) on the Display Adjustment PC board in the A3A2 slot as shown in Figure 3-23.

Note The pulse/function generator???s output must be terminated with 50 ohms. Use a BNC tee, a 5Ofl termination, and a BNC female to SMB female adapter. Install the 5052 termination as close to the Display Adjustment PC Board as possible.

3-54 Adjustments

3.Preliminary Display Adjustments (SN 3004A and Above)

12.Set the oscilloscope controls as follows:

13.Set the spectrum analyzer???s front-panel INTENSITY control fully counterclockwise, and then set the LINE switch to ON.

14.The X+ deflection and X- deflection waveforms should be

superimposed on the oscilloscope display, as shown in Figure 3-26. If necessary, adjust AlA2R227 X POSN and AlA2R220 X GAIN for a centered display of at least four vertical divisions. See Figure 3-25 for the location of the adjustments.

hf r u n n i n g

1 1 0 . 0 V/div offset: 2 5 . 0 0 V

10.00 : I dc

4 1 0 . 0 V/div offset: 6 0 . 0 0 v 10.00 : I dc

8..

- 1 2 5 . 0 0 0 ns

1 f 25.00 V

Figure 3-26. X + and X- Waveforms

15. Set the oscilloscope controls as follows:

Press [WFORM MATH):

f l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..on display . . . . . . . . . . . .. .. .. .. .. . .. .. .. . . . . . . . . . . . . . . . . . . .. .. on math . . . . . . . . . . . . . . . .. . . . . . . . . . . channel 1 - channel 4 sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...25.0 Vldiv

16.Three waveforms should be displayed on the oscilloscope, as shown in Figure 3-27. The lower composite waveform represents

Adjustments 3-55

3. Preliminary Display Adjustments (SN 3004A and Above)

the combined X deflection voltage applied to the CRT. Use the oscilloscope???s front-panel knob to adjust waveform fl sensitivity for approximately 8 vertical divisions.

hp r u n n i n g

: 1 2 0 . 0 V/div

o f f s e t : 2 5 . 0 0 V

.I

..:..

:::. .:. ::.:::::.::.:::..

~~~~:~...~I;::r~i~~~-:1.

.:

- 1 2 5 . 0 0 0 ns1 2 5 . 0 0 0 ns3 7 5 . 0 0 0 ns 5 0 . 0 ns/dlv

1 f 25.00 V

Figure 3-27. Composite X Deflection Waveform

17.Adjust AlA2R217 HF GAIN, AlA2C204, and AlA2C209 for minimum overshoot and minimum rise and fall times of the composite X deflection waveform.

Note Always adjust AlA2C204 and AlA2C209 in approximately equal amounts. Do not adjust one to its minimum value and the other to its maximum value.

18.Use the oscilloscope Intnv] markers to measure the risetime, falltime, and percent overshoot of the composite X defection waveform. Rise and fall times should both be less than approximately 65 ns between the 10% and 90% points on the waveform. Overshoot should be less than 3% (approximately 0.25 divisions). See Figure 3-28.

O V E R S H O O T

9 0 %

O V E R S H O O T

Figure 3-28.

Rise and Fall Times and Overshoot Adjustment Waveform

3.56 Adjustments

3.Preliminary Display Adjustments (SN 3004A and Above)

19.Connect the oscilloscope???s channel 1 probe to AlA2TP104 and the channel 4 probe to AlA2TP105. See Figure 3-25 for the location of the test points. Connect the output of the pulse/function generator to 52 (Y input) on the Display Adjustment PC board in the A3A2 slot.

20.The Y Deflection Amplifier is identical to the X Deflection Amplifier. Repeat steps 12 through 18 for the Y Deflection Amplifier using R127, R120, R117, C104, and C109, respectively.

Pulse Response of 21. Disconnect the oscilloscope channel 4 probe from the spectrum

23.Press m, CHANNEL 1 on, more preset probe , and use the front-panel knob to set the probe to lO.OO:l. Press more .

24.Set the oscilloscope controls as follows:

25.Connect the output of the Pulse/Function Generator to 53 (Z input) on the Display Adjustment PC Board in the A3A2 slot. Set the board???s switch to the down position.

Note The pulse/function generator???s output must be terminated with 50 ohms. Use a BNC tee, a 500 termination, and a BNC female to SMB female adapter. Install the 500 termination as close to the Display Adjustment PC Board as possible.

26. Set the Pulse/Function Generator???s controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NORM

Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..pulse

Frequency (FRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 kHz

Width (WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 ns

Amplitude (AMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.OOV

Offset (OFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.OOV

27.Disconnect the black connector with three wires (8, 98, and 96) from AlA2J5, and set AlA2R319 INT GAIN fully clockwise.

28.Set the spectrum analyzer???s front-panel INTENSITY control fully clockwise. Adjust the oscilloscope trigger level for a stable display. Note the display on the oscilloscope. The pulse should be >55V peak-to-peak.

Adjustments 3.57

3.Preliminary Display Adjustments (SN 3004A and Above)

29.Set the oscilloscope controls as follows:

30.Adjust the spectrum analyzer???s front-panel INTENSITY control for 50V peak-to-peak (8 divisions) as indicated on the oscilloscope. See Figure 3-29.

hf r u n n i n g

1 f 50.00 v

Figure 3-29. 5OV,., Signal

31.Adjust AlA2R308 HF GAIN and AlA2C307 for minimum overshoot on rise and minimum rise and fall times of the pulse waveform.

32.Use the oscilloscope Intav) markers to measure the risetime, falltime, and percent overshoot of the pulse waveform. Rise and falltimes should be less than 50 ns and 90 ns respectively. Overshoot on the rise should be less than 5% (approximately 0.4 divisions).

33.Set the spectrum analyzer???s LINE switch to STANDBY and reconnect the cable to AlA2J5.

34.Disconnect the oscilloscope channel 1 probe from the spectrum analyzer. Remove the Display Adjustment PC board from the A3A2 slot, and reinstall the A3A2 Intensity Control Assembly. Replace the A3 Section cover and cables.

35.Reconnect the black connector with three wires (8, 98, and 96) to AlA2J5, and set AlA2R319 INT GAIN approximately two-thirds clockwise.

36.Perform Adjustment Procedure 4 Final Display Adjustment (SN 3004A and Above).

3-58 Adjustments

4. Final Display

Adjustments (SN

3001A and Below)

Reference

4. Final Display Adjustments (SN 3001A and Below)

AlAl Keyboard

AlA Z Axis Amplifier

AlA X Deflection Amplifier

AlA Y Deflection Amplifier

Description

Note

Procedure

Note

This procedure is used to optimize the appearance of the CRT display during routine maintenance or after CRT replacement or minor repairs. First, the display is adjusted for best focus over the full CRT, then the graticule pattern is adjusted for optimum rectangular display.

Adjustment Procedure 2, High Voltage Adjustment (SN 3001A and Below) should be performed prior to performing the following adjustment procedure.

1.With the spectrum analyzer LINE switch set to STANDBY, set the potentiometers listed in lhble 3-5 as indicated. See Figure 3-30 for the location of the adjustments.

In this procedure, do not adjust the following potentiometers and precision variable capacitors on the AlA Z-Axis Amplifier, AlA X-Axis Amplifier, or AlA Y-Axis Amplifier Assemblies: AlA2R36 INT LIMIT, AlA2R22 HF GAIN, AlABClO, AlA4R28 HF GAIN, AlA4C10, AlA4Cl1, AlA5R28 HF GAIN, AlA5C10, or AlA5Cll. These components are adjusted in Adjustment Procedure 2, High Voltage Adjustments (SN 3001A and Below) and Adjustment Procedure 3, Preliminary Display Adjustments (SN 3001A and Below).

???Ihble 3-5. Initial Adjustment Positions

2.Set the LINE switch to ON and wait at least 5 minutes to allow the CRT and high-voltage circuits to warm up. The spectrum analyzer power-up annotation should be visible on the CRT display.

3.For an initial coarse focus adjustment, adjust AlA3R15 FOCUS LIMIT, AlA2R36 ASTIG, and AlA2R30 FOCUS GAIN in sequence for best displayed results.

4.Adjust AlA4R7 X POSN, AlA4R27 X GAIN, AlA5R7 Y POSN, and AlA5R27 Y GAIN for optimum centering of the display annotation and graticule pattern.

Adjustments 3-59

4.Final Display Adjustments (SN 3001A and Below)

5.For best overall focusing of the display, adjust the following

potentiometers in the sequence listed below:

a.AlA3R14 FOCUS LIMIT for best focus of graticule lines (long vectors)

b.AlA2R36 ASTIG

c.AlA2R30 FOCUS GAIN for best focus of annotation (short vectors)

6.Adjust AlA2R31 ORTHO, the front-panel ALIGN control, and AlA2R32 PATT to optimize the orientation and appearance of the rectangular graticule pattern on the CRT display.

7.Repeat steps 4 through 6 as needed to optimize overall display focus and appearance.

AIAZ

Figure 3-30.

Location of Final Display Adjustments on AlA2, AlA4, and AlA

3-60 Adjustments

4. Final Display Adjustments (SN 3004A and Above)

4. Final Display

Adjustments (SN

3004A and Above)

Reference AlAl Keyboard

AlA X, Y, Z Axis Amplifiers

Description This procedure is used to optimize the appearance of the CRT display during routine maintenance or after CRT replacement or minor repairs. First, the display is adjusted for best focus over the full CRT, then the graticule pattern is adjusted for optimum rectangular display.

Equipment Digital Photometer . . . . . . . . . . . . . . . . . . . . . . . . .Tektronix J-16, Option 02 Photometer Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Tektronix 56503 Photometer interconnect cable . . . . . . . . . . . . . . . Tektronix 012-0414-02 Photometer light occluder . . . . . . . . . . . . . . . . . . . . .Tektronix 016-0305-00

Procedure

Note

Adjustment Procedure 2, High Voltage Adjustment (SN 3004A and Above) should be performed prior to performing the following adjustment procedure.

1. Connect the equipment as shown in Figure 3-31.

SPECTRUl ANALYZER

Figure 3-31. Final Display Adjustments Setup

2.Set the photometer probe to NORMAL. Press [POWER_) on the photometer to turn it on and allow 30 minutes warm-up. Zero the photometer according to the manufacturer???s instructions.

3.With the spectrum analyzer???s LINE switch set to STANDBY, set the potentiometers listed in the ???Iable 3-6 as indicated. See Figure 3-32 for the location of the adjustments.

Note In this procedure, do not adjust the following potentiometers and variable capacitors on the AlA X, Y, Z Amplifier Assembly: C104, C109, C204, C209, C307, R117, R217, or R308. These components are adjusted in the factory and in Adjustment Procedure 3, Preliminary Display Adjustments (SN 3004A and Above).

Adjustments 3.61

4. Final Display Adjustments (SN 3004A and Above)

Figure 3-32. Location of Final Display Adjustments on AlA

???Ihble 3-6. Initial Adjustment Positions

4.Set the spectrum analyzer???s LINE switch to ON, and wait at least 5 minutes to allow the CRT and high-voltage circuits to warm up.

5.Set the front panel INTENSITY control fully counterclockwise and adjust AlA2R516 INT LIM until the display is just visable. See Figure 3-32.

6.Set the front-panel INTENSITY control fully clockwise.

7.Adjust AlA2R220 X GAIN, AlA2R227 X POSN, AlA2R120 Y GAIN, and AlA2R127 Y POSN for optimum centering of the

display annotation and graticule pattern.

3-62 Adjustments

Note

Note

4.Final Display Adjustments (SN 3004A and Above)

8.For an initial coarse focus, adjust the following potentiometers in the sequence listed:

AlA3R14 FOCUS LIMIT

AlA2R517 ASTIG

AlA2R513 3D

AlA2R409 FOCUS COMP

9. Press QNSTR PRESET), then adjust the reference level to bring the displayed noise to the top division of the graticule. Press CENTER dB/DIvj and key in 1 dB/DIV. The noise should now completely fill the CRT graticule pattern, illuminating a large

rectangular area. If necessary, adjust the reference level until the graticule pattern is completely filled.

10.Press ISHIFT) (oFF)m and then C-1 loFFp to turn off the CRT annotation and graticule pattern.

Connect a 56503 photometer probe to the Tektronix J-16 digital photometer. Set the photometer to the Xl range.

11.Place the photometer light probe hood against the IF-Display Section glass RF1 filter, and adjust AlA2R319 INT GAIN for a photometer reading of 80 NITS (cd/m???).

This reading must be made with the glass RF1 filter in place in front of the CRT. It might be necessary to slightly trim the top and bottom of the photometer probe???s hood so that it will fit flush against the glass RF1 filter.

If a standard J-16 photometer is used (instead of metric option OZ), adjust AlA2R319 for a photometer reading of 23.5 fl (footlamberts).

12.Set the LINE switch to STANDBY and then back to ON. The spectrum analyzer power-up annotation should be visible on the CRT display. (This includes the firmware datecode.)

13.For the best focus near the center of the CRT display, adjust the following potentiometers in the sequence listed below. Repeat as needed to optimize center-screen focus.

AlA3R14 FOCUS LIMIT AlA2R517 ASTIG

AlA2R513 3D for best focus of annotation (short vectors) AlA2R409 FOCUS COMP for best focus of graticule lines (long vectors)

14.Adjust AlA2R426 T/B FOC for best focus at the top and bottom of the display.

15.Adjust AlA2R437 R/L FOC for best focus at the right and left sides of the display.

16.If the top and bottom (or right and left sides) of the display achieve best focus at different potentiometer settings, adjust AlA2R427 T/B CTR or AlA2R440 R/L CTR, and then readjust AlA2R426 T/B FOC or AlA2R437 R/L FOC to optimize overall focus.

Adjustments 3-63

4.Final Display Adjustments (SN 3004A and Above)

17.Adjust AlA2R512 ORTHO and the front-panel ALIGN control to optimize the orientation and appearance of the rectangular graticule pattern on the CRT display.

18.Repeat steps 13 through 17 as needed to optimize overall display focus and appearance.

3-64 Adjustments

5. Log Amplifier

Adjustments

Reference

5. Log Amplifier Adjustments

IF-Display Section

A4A3 Log Amplifier-Filter

A4A2 Log Amplifier-Detector

Related Performance

Tests

Note

Scale Fidelity Test

The A4A3 Log Amplifier-Filter and A4A2 Log Amplifier Detector are temperature compensated as a matched set at the factory. In the event of a circuit failure, a new matched set must be ordered. Contact your nearest HP Service Center.

Description First, the A4A2 Log Amplifier-Detector ZERO adjustment is checked and adjusted if necessary, then the A4A3 Log Amplifier-Filter is set for center frequency by injecting a signal and adjusting the bandpass filter center adjustment for maximum DVM indication. The bandpass filter amplitude is adjusted by monitoring the output of the filter control line shorted and not shorted to the + 15V supply. Next, log fidelity (gain and offset of the log curve) is adjusted by adjusting the -12 VTV and the PIN diode attenuator. Last, the linear gain step adjustments are performed to set the proper amount of step gain in the linear mode of operation.

S Y N T H E S I Z E R L E V E L

GENERAT 6R

D I G I T A L V O L T M E T E R

S P E C T R U M A N A L Y Z E R ???$,,,

I

Equipment

Procedure

Figure 3-33. Log Amplifier Adjustments Setup

Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A

1.Position instrument upright as shown in Figure 3-33, with top cover removed.

2.Set LINE switch to ON and press (INSTR PRESET].

3.Key in [FREQUENCY SPAN) 0 Hz, &ENTER FREQUENCY] 7.6 MHz,

CREFERENCE LEVEL_) + 10 dBm, [RESBW) 10 kHz, and press LIN pushbutton.

Adjustments 3-65

5. Log Amplifier Adjustments

4. Connect DVM to A4AlTPl and DVM ground to the IF casting. Connect the frequency synthesizer to the RF INPUT. Key in CFREQUENCY) 80 MHz and [AMPLITUDE) -86.98 dBm. The frequency synthesizer will now provide a 5OfI load.

Offset Adjustment Check

5.Adjust A4A2R79 ZERO for 0.0000 f0.0005 V dc. See Figure 3-34 for location of adjustment.

A4A2

A4A3

Figure 3-34. Location of Log Amplifier Adjustments

Bandpass Filter Center Adjustment

6.Press LOG (ENTER dB/DIv)

7.Set the frequency synthesizer for 7.6000 MHz at +5.0 dBm output level.

8.Adjust A4A3C55 CTR for maximum DVM indication. See Figure 3-34 for location of adjustment. If A4A3C55 is at an extreme of its adjustment range (fully meshed, maximum capacitance, or unmeshed, minimum capacitance), increase or

decrease value of A4A3C52 and A4A3C53. Refer to ???able 3-3 for range of values.

Note A4A3C52 is a fine adjustment, and A4A3C53 is a coarse adjustment. If A4A3C55 is fully meshed, increase the value of A4A3C52 or A4A3C53.

3.66 Adjustments

5. Log Amplifier Adjustments

Bandpass Filter Amplitude Adjustment

9.Connect one end of a jumper wire to A4A3TP8. Connect the other end of the jumper to A4A3TP7 (+ 15V). Connecting the

jumper to A4A3TP8 first reduces the chance of shorting the + 15V to ground. Note DVM indication.

V dc

10.Remove the short from between A4A3TP7 and A4A3TP8.

11.Adjust A4A3R67 AMPTD for DVM indication the same as that

noted in step 9 f0.0005 V dc. See Figure 3-34 for location of adjustment. If unable to adjust A4A3R67 AMPTD for proper indication, increase or decrease value of A4A3R66. (If A4A3R67 is fully counter-clockwise, increase the value of A4A3R66.)

Refer to Table 3-3 for range of values.

12.Repeat steps 9 through 11 until DVM indication is the same f0.0005 V dc with A4A3TP7 jumpered to A4A3TP8, and with A4A3TP7 and A4A3TP8 not jumpered. Remove the jumper.

-12 VTV and ATTEN Adjustments

13.Press LIN pushbutton.

14.Adjust frequency synthesizer output level for DVM indication of

+1.000 &IO.0002 V dc.

15.Press LOG [ENTER dB/DIV)

16.Wait three minutes for the log assemblies to stabilize.

17.Decrease the frequency synthesizer output level by 50 dB.

18.Adjust A4A2R91 - 12 VTV for DVM indication of + 500 f 1 mV dc. See Figure 3-34 for location of adjustment.

19.Increase the frequency synthesizer output level by 50 dB (to the level of step 14).

20.Adjust A4A2R61 ATTEN for DVM indication of + 1.000 *O.OOOl V

dc. See Figure 3-34 for location of adjustment. If unable to adjust A4A2R61 ATTEN for proper indication, increase or decrease value of A4A2R62. (If A4A2R61 is fully clockwise, increase the value of A4A2R62.) Refer to ???Ihble 3-3 for range of values.

21.Repeat steps 17 through 20, until specifications of steps 18 and 20 are achieved without further adjustment. Because adjustments A4A2R61 and A4A2R91 are interactive, several iterations are needed.

Linear Gain Adjustments

22.Press LIN pushbutton. DVM indication at A4AlTPl should be

+1.000 f0.020 V dc (+ 0.980 to + 1.020 V dc). If indication is not within this range, repeat steps 14 through 21. If indication is within this range, press [*I CENTER dB/div] q. This disables the IF step gains.

Adjustments 3-67

5. Log Amplifier Adjustments

23.Decrease the frequency synthesizer???s output level 10 dB. Press CREFERENCE LEVEL) 0 dBm, and adjust the frequency synthesizer???s output level for a DVM indication of + 1.00 k.001 Vdc.

24.Verify that attenuator is set at 10 dB. Decrease the frequency synthesizer output level by 10 dB. Press [REFERENCE LEVEL] -60 dB.

25.Adjust A4A3R83 LGlO for DVM indication of + 1.000 kO.010 V dc. See Figure 3-34 location of adjustment. If unable to adjust LGlO for proper indication, increase or decrease value of A4A3R54. Refer to Table 3-3 for range of values.

26.Decrease the frequency synthesizer output level by 10 dB.

27.Key in [REFERENCE LEVEL_) -70 dB.

28.Adjust A4A2R14 LG20 for DVM indication of + 1.000 fO.O1O

V dc. See Figure 3-34 for location of adjustment. If unable to adjust LG20 for proper indication, increase or decrease value of A4A2R18. Refer to lkble 3-3 for range of values.

29. Press [INSTR PRESET] to reenable IF Step Gains.

3.66 Adjustments

6. Video Processor

Adjustments

Reference

Related Performance

Test

Description

6. Video Processor Adjustments

IF-Display Section

A4A 1 Video Processor

Log Scale Switching Uncertainty Test

The CAL OUTPUT signal is connected to the RF INPUT through a step attenuator. The instrument is placed in zero frequency span to produce a dc level output from the log amplifier. The A4A2 ZERO adjustment, which sets the dc offset of the output buffer amplifier of the log board, is checked and adjusted if necessary. The dc level into the video processor is adjusted by varying the input signal level and reference level. The offsets and gains on the A4Al Video Processor are adjusted for proper levels using a DVM.

Equipment

Note

Procedure

D I G I T A L V O L T M T E R

0 cd

1OdB S T E P A T T E N U A T O R

Figure 3-35. Video Processor Adjustments Setup

Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A 10 dB Step Attenuator . . . . . . . . . . . . . . . . . . . . . . . . . . HP 355D

The voltage at A4AlTP3 may drift noticeably with temperature during this adjustment. Allow A4Al (Video Processor) to warm up at least one-half hour prior to adjustment.

1.Position instrument upright as shown in Figure 3-35. Remove the top cover.

2.Set LINE switch to ON and press (INSTR PRESET).

3.Connect DVM to A4AlTPl and DVM ground to the IF casting.

4.Connect CAL OUTPUT to RF INPUT through 10 dB step attenuator.

5.Key in [CENTER FREQUENCY) 20 MHz and [FREQUENCY SPAN) 0 Hz.

Press LIN pushbutton.

Adjustments 3-69

6.Video Processor Adjustments

6.Set step attenuator to 120 dB. DVM indication should be 0.000 *0.0005 V dc. (If DVM indication is out of tolerance, adjust A4A2R79 ZERO on the log amplifier-detector board..)

7.Set step attenuator to 0 dB.

8.Key in [Reference LWI) and adjust DATA knob for DVM indication as close to + 1.000 fO.OO1 V dc as possible. (It may be necessary to slightly adjust the front panel AMPTD CAL control to achieve required tolerance.)

9.Connect DVM to A4AlTP2.

10.Adjust A4AlR14 OS for a DVM indication of 0.000 f0.003 Vdc. See Figure 3-36 for the location of the adjustment.

A4A 1

Figure 3-36. Location of Video Processor Adjustments

11.Connect the DVM to A4AlTP3.

12.Set the step attenuator to 120 dB.

13.Adjust A4AlR32 ZERO for a DVM indication of 0.000 rtO.001 Vdc.

14.Set the step attenuator to 0 dB.

15.Adjust A4AlR36 FS for DVM indication of +2.000 f 0.001 V dc.

16.Repeat steps 12 through 15 until specifications of steps 13 and 15 are met.

LOG Offset Adjust

17.Set step attenuator to 40 dB.

18.Key in Cm), (m) I, LOG (ENTER dt3/mv), (SHIFT) [ENTER dB/DIv

q, PREFERENCE L E V E L ] -50 dBm.

19.Connect DVM to A4AlTPl. Record DVM indication. Indication should be approximately +0.500 V dc.

V de

20.Decrease reference level to -60 dBm using the step key.

21.Adjust A4AlR2 LG OS for DVM indication of +O.lOO +O.OOl V dc greater than the DVM indication recorded in step 19. See

Figure 3-36 for location of adjustment.

3-70 Adjustments

6. Video Processor Adjustments

22.Decrease reference level to -70 dBm using the step key.

23.DVM indication should be +0.200 ??? 0.002 V dc greater than the indication recorded in step 19. If not, readjust A4AlR2 LG OS.

24.Decrease reference level to -90 dBm using the step key.

25.DVM indication should be +0.400 f0.004 V dc greater than the indication recorded in step 19. If not, readjust A4AlR2 LG OS.

26.Repeat steps 17 through 25 until the specifications are met.

Adjustments 3-7 1

7. 3 MHz

Bandwidth Filter

Adjustments

Reference

Related Performance

Test

Description

IF-Display Section

A4A7 3 MHz Bandwidth Filter

Resolution Bandwidth Switching Uncertainty Test

Resolution Bandwidth Selectivity Test

With the CAL OUTPUT signal connected to the RF INPUT, the 18.4 MHz oscillator can be adjusted with the FREQ ZERO control (on the front panel) to peak the IF signal for maximum amplitude for the center of the 3 MHz bandpass. Each of the five stages of the 3 MHz Bandwidth Filter is adjusted for bandpass centering and symmetry. Four crystal filter bypass networks are required for alignment of the filter stages. See Figure 3-91 for information concerning the bypass networks.

A stable 21.4 MHz signal is then applied to the IF section of the instrument from a frequency synthesizer. Each of the first four stages of the 3 MHz Bandwidth Filter is peaked in a 10 Hz bandwidth using an oscilloscope display. The final stage is peaked using the spectrum analyzer CRT display.

After all five filter stages are adjusted for centering, symmetry, and peaking, the CAL OUTPUT signal is used to match the 10 Hz and 1 kHz bandwidth amplitudes.

Figure 3-37. 3 MHz Bandwidth Filter Adjustments Setup

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . HP3335A Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 545OlA Crystal Filter Bypass Network (???t required) See Figure 3-91 Test Cable: BNC to SMB snap-on . . . . . . . . . . HP 85680-60093

3-72 Adjustments

7. 3 MHz Bandwidth Filter Adjustments

Procedure 1. Position instrument upright as shown in Figure 3-37 and remove top cover.

2. Set LINE switch to ON and press ~NSTR PRESET).

Frequency Zero Check

3.Connect CAL OUTPUT signal to RF INPUT

4.Key in IRECALL) @.

5.Adjust front panel FREQ ZERO control for maximum signal amplitude on the CRT display.

Filter Center and Symmetry Adjustments

6.Key in ~CENTER FREQUENCY) 20 MHz, CFREQUENCY SPAN) 10

kHz, [REsBWI) 1 kHz, and press LIN pushbutton. Press

CREFERENCE LEVEL] and adjust reference level, using step keys and front-panel knob to place signal peak near top CRT graticule line.

7.On the A4A7 assembly, connect crystal filter bypass networks between the pins above C41 SYM, C32 SYM, C23 SYM, and Cl4 SYM.

8.Adjust A4A7C7 CTR for minimum amplitude signal peak. Adjust A4A7C6 SYM for best symmetry of signal. Repeat adjustments to ensure that the signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

A4A7

3 MHz B a n d w i d t h F i l t e r

A4A7

Figure 3-38.

Location of Center, Symmetry, and 10 Hz Amplitude

Adjustments

9. Remove crystal filter bypass network near Cl4 SYM.

Adjustments 3-73

7.3 MHz Bandwidth Filter Adjustments

10.Adjust A4A7C15 CTR for minimum amplitude of signal peak. Adjust A4A7C14 SYM for best symmetry. Repeat adjustments to ensure that the signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

11.Remove crystal filter bypass network near C23 SYM.

12.Adjust A4A7C24 CTR for minimum amplitude of signal peak. Adjust A4A7C23 SYM for best symmetry of signal. Repeat adjustments to ensure that signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

13.Remove crystal filter bypass network near C32 SYM.

14.Adjust A4A7C33 CTR for minimum amplitude of signal peak. Adjust A4A7C32 SYM for best symmetry of signal. Repeat adjustments to ensure that signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

15.Remove crystal filter bypass network near C41 SYM.

16.Adjust A4A7C42 CTR for minimum amplitude of signal peak. Adjust A4A7C41 SYM for best symmetry of signal. Repeat adjustments to ensure that the signal is nulled and adjusted for best symmetry. See Figure 3-38 for location of adjustments.

17.Signal should be centered on center graticule line on CRT display. If signal is not centered, go back to step 3 and repeat adjustments of each filter stage.

Filter Peak Adjust

18.Press (JNSTR PRESET].

19.Key in CSWEEP TIME] 20 ms, [FREQUENCY SPAN) 0 Hz, CREs] 10 Hz,

[R E F E R E N C E L E V E L ) -20 dBm.

20.Set the frequency synthesizer for 21.400 MHz at an amplitude level of -25.0 dBm.

21.Disconnect cable 97 (white/violet) from A4A8Jl and connect output of the frequency synthesizer to A4A8Jl using BNC to SMB snap-on cable.

22.Set the oscilloscope following settings:

Channel 1

amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.005 V/div time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...0.2 psldiv mag x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 (vertical) . coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..ac probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1O:l

Channel 2

amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O.O05V/div coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ac probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1O:l

23.Connect oscilloscope Channel 1 probe to A4A7TP7 (left side of Cl4 SYM) and Channel B probe to A4A7TP5 (left side of C23 SYM).

24.Adjust frequency synthesizer output frequency to peak Channel 1 display.

3-74 Adjustments

7.3 MHz Bandwidth Filter Adjustments

25.Adjust A4A7C13 PK for maximum peak-to-peak signal on Channel 2 display. See Figure 3-39 for location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C12. Refer to Table 3-3 for range of values.

A4A7

3 M H z B a n d w i d t h F i l t e r

Figure 3-39. Location of 3 MHz Peak Adjustments

26.Move Channel 2 probe to A4A7TP3 (left side of C32 SYM).

27.Adjust frequency synthesizer output frequency to peak Channel 1 display.

28. Adjust A4A7C22 PK for maximum peak-to-peak signal on Channel 2 display. See Figure 3-39 for location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C21. Refer to Table 3-3 for range of values.

29. Move Channel 2 probe to A4A7TPl (left side of C41 SYM).

30. Adjust frequency synthesizer output frequency to peak Channel 1 display.

31. Adjust A4A7C31 PK for maximum peak-to-peak signal on Channel 2 display. See Figure 3-39 for location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C30. Refer to ???Iable 3-3 for range of values.

32.Disconnect Channel 2 probe from A4A7TPl.

33.Adjust frequency synthesizer output frequency to peak Channel 1 display.

34.Adjust [REFERENCE LEVEL_) using step keys to place signal near top CRT graticule line.

35.Adjust A4A7C40 PK for maximum signal amplitude on the CRT

display. See Figure 3-39 for the location of adjustment. If unable to achieve a ???peak??? in signal amplitude, increase or decrease value of A4A7C39. Refer to Table 3-3 for range of values.

36. Disconnect Channel 1 probe from A4A7TP7. Disconnect ???frequency synthesizer output from A4A8Jl and reconnect cable 97 (white/violet).

Adjustments 3-75

7. 3 MHz Bandwidth Filter Adjustments

10 Hz Amplitude Adjustments

37.Connect CAL OUTPUT to RF INPUT. Key in [INSTR PRESET), [mj 9, (jEEki-- 10 Hz.

38.Adjust the instrument front panel FREQ ZERO control for maximum signal amplitude on the CRT display.

40.Key in [REs] 10 Hz.

41.Adjust the instrument front panel FREQ ZERO control for maximum signal amplitude on the CRT display.

42.Adjust A4A7R30 10 Hz AMPTD and A4A7R41 10 Hz AMPTD equal amounts to set the signal level the same as the reference level set in step 39. See Figure 3-38 for location of 10 Hz AMPTD adjusts.

43.Repeat steps 37 through 42 until no further adjustment is required.

3-76 Adjustments

8. 21.4 MHz Bandwidth Filter Adjustments

8. 21.4 MHz

Bandwidth Filter

Adjustments

Reference IF-Display Section

A4A4 Bandwidth Filter

A4A8 Attenuator-Bandwidth Filter

Related Performance

Tests

Description

IF Gain Uncertainty Test

Resolution Bandwidth Switching Uncertainty test

Resolution Bandwidth Selectivity Test

First the LC Filters (100 kHz to 3 MHz bandwidths) on the A4A4 Bandwidth Filter are adjusted. The crystal filter poles (3 kHz to 30 kHz bandwidths) are then adjusted for center and symmetry by bypassing all but one pole at a time and adjusting the active pole.

Next, the LC filters and the crystal filter poles on the A4A8 Attenuator-Bandwidth Filter are adjusted in the same manner as on the A4A4 Bandwidth Filter.

Last, the 10 dB and 20 dB attenuators on the A4A8 Attenuator- Bandwidth Filter are adjusted for the proper amount of attenuation. This is done by connecting the CAL OUTPUT signal to the RF INPUT through two step attenuators, keying in the necessary reference level to activate the 10 dB and the 20 dB control lines, adjusting the step attenuators to compensate for the attenuation, and adjusting the attenuators for the proper amount of attenuation.

DIGITAL VOLTMETER

rm

1OdB STEP IdH STEP

ATTENUATOR ATTENUATOR

Figure 3-40. 21.4 MHz Bandwidth Filter Adjustments Setup

Adjustments 3-77

8. 21.4 MHz Bandwidth Filter Adjustments

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . .HP 3456A 10 dB Step Attenuator . . . . . . . . . . . . . . HP 355D, Option H89 1 dB Step Attenuator . . . . . . . . . . . . . . . HP 355C, Option H25

Crystal Filter Bypass Network (2 required) . . . . Refer to Figure 3-91

Procedure 1. Position instrument upright as shown in Figure 3-40 and remove top cover.

2.Set LINE switch to ON and press QNSTR PRESET].

+10 V Temperature Compensation Supply Check

3.Connect DVM to A4A5TPl (+ 10 VF).

4.DVM indication should be between +9.0 V dc and + 10.0 V dc. If voltage is within tolerance, proceed to next step. If voltage is not

within tolerance, refer to Adjustment 10, Step Gain and 18.4 MHz Local Oscillator Adjustments, for adjustment procedure.

A4A4 LC Adjustments

5.Set step attenuators to 0 dB.

6.Disconnect cable 97 (white/violet) from A4A8Jl and connect to A4A6J 1.

7.Key in CCENTER FREQ] 20 MHz, (jREs] 100 kHz, [FREQUENCY SPAN) 200 kHz, and press LIN pushbutton.

8.Press (REFERENCE LEVEL) and adjust front-panel knob to set signal peak on screen two divisions from the top graticule.

9.Adjust A4A4C67 LC CTR and A4A4C19 LC CTR for maximum MARKER level as indicated by CRT annotation. See Figure 3-41 for location of adjustments. If unable to adjust LC CTR adjustments for satisfactory signal amplitude, increase or decrease value of A4A4C17 and A4A4C70. Refer to Table 3-3 for range of values.

A4A4

Bnndwdth Filte

\

c

Figure 3-41.

Location of A4A4 21.4 MHz LC Filter Adjustments

3-78 Adjustments

8.21.4 MHz Bandwidth Filter Adjustments

10.Key in CRESBW_) 1 MHz, and ISPAN) 1 MHz.

11.Press MARKER CPEAK SEARCH], MARKER a.

12.Key in CREsBW) 100 kHz, [-SPAN) 200 kHz, and MARKER

[PEAK SEARCH).

13.Adjust A4A4R43 LC to align markers on display. MARKER A level should indicate 1.00 X. See Figure 3-41 for location of adjustment.

14.Repeat steps 10 through 13 until no further adjustment is necessary.

A4A4 XTAL Adjustments

15. Press MARKER loFF). Key in CREsJ 30 kHz and

[FREQUENCY SPAN] 100 kHz.

16.Press [REFERENCE LEVEL) and adjust DATA knob to set signal peak on screen two divisions from the top graticule line.

17.Connect crystal filter bypass networks between A4A4TPl and A4A4TP2 and between A4A4TP4 and A4A4TP5.

18.Adjust A4A4C20 CTR to center signal on center graticule line. Adjust A4A4C9 SYM for best symmetry of signal. See

Figure 3-42 for location of adjustments. If unable to adjust SYM for satisfactory signal symmetry, increase or decrease value of A4A4ClO. Refer to Table 3-3 for range of values.

A4A4

B a n d w i d t h F i l t e r

A4A4

Figure 3-42.

Location of A4A4 21.4 MHz Crystal Filter Adjustments

19.Remove crystal filter bypass network from between A4A4TP4 and A4A4TP5.

20.Adjust A4A4C74 CTR to center signal on center graticule line. Adjust A4A4C39 SYM for best symmetry of signal. See Figure 3-42 for location of adjustments. If unable to adjust A4A4C39 SYM

for satisfactory signal symmetry, increase or decrease value of A4A4C38. Refer to Table 3-3 for range of values.

21.Remove crystal filter bypass network from between A4A4TPl and A4A4TP2.

Adjustments 3.79

8.21.4 MHz Bandwidth Filter Adjustments

22.Adjust A4A4C73 CTR to center signal on center graticule line. Adjust A4A4C65 SYM for best symmetry of signal. See Figure 3-42 for location of adjustments. If unable to adjust A4A4C65 SYM

for satisfactory signal symmetry, increase or decrease value of A4A4C66. Refer to Table 3-3 for range of values.

23.All crystal filter bypass networks are removed. Signal should be centered and symmetrical. If not, go back to step 16 and repeat adjustments.

24.Press MARKER SPEAK SEARCH] and MARKER In].

25.Key in ~FREQUENCY SPAN] 20 kHz, [REs] 3 kHz, and MARKER

[PEAK SEARCH].

26.Adjust A4A4R49 XTAL to align markers on display. MARKER A level should indicate 1.00 X. See Figure 3-42 for location of adjustment.

A4A8 LC Adjustments

27.Disconnect cable 97 (white/violet) from A4A6Jl and reconnect to A4A8Jl. Reconnect cable 89 (gray/white) to A4A6Jl.

28.Key in [-BW) 100 kHz and [FREQUENCY SPAN] 200 kHz.

29.Press [REFERENCE LEVEL) and adjust DATA knob to place signal peak two division from the top graticule line.

30.Adjust A4AW32 LC CTR and A4A8C46 LC CTR for maximum MARKER level as indicated by CRT annotation. See Figure 3-43 for location of adjustments. If unable to adjust A4A8C32 and A4AW46 LC CTR adjustments for satisfactory signal amplitude, increase or decrease value of A4AW35 and A4A8C49. Refer to ???Iable 3-3 for range of values.

A4A8

A t t e n u a t o r BandwIdth F i l t e r

A4A8

Figure 3-43.

Location of A4A8 21.4 MHz LC Filter and Attenuation

Adjustments

31.Key in [REsj 1 MHz and @@?ZGGi] 1 MHz.

32.Press MARKER (PEAK SEARCH] and MARKER @.

3-80 Adjustments

8.21.4 MHz Bandwidth Filter Adjustments

33.Key in t-1 100 kHz, C-1 200 kHz, and MARKER

[PEAK SEARCH].

34.Adjust A4A8R35 LC to align makers on display. MARKER A level should indicate 1.00 X. See Figure 3-43 for location of adjustment.

35.Repeat steps 31 through 34 until no further adjustment is necessary.

A4A8 XTAL Adjustments

36.Key in @TFTiTj 30 kHz, [FREQUENCY SPAN] 100 kHz. Press

MARKER IOFF).

37.Connect crystal filter bypass network between A4A8TPl and A4A8TP2.

38.Press (REFERENCE LEVEL) and adjust DATA knob to place signal peak two division from the top graticule line.

39.Adjust A4ASC44 CTR to center signal on center graticule line. Adjust A4A8C42 SYM for best symmetry of signal. See Figure 3-44 for location of adjustments. If unable to adjust A4A8C42 SYM

for satisfactory signal symmetry, increase or decrease value of A4A8C43. Refer to Table 3-3 for range of values.

A4A8

A t t e n u a t o r - B a n d w i d t h F i l t e r

A4A8

Figure 3-44.

Location of A4A8 21.4 MHz Crystal Filter Adjustments

40.Remove crystal filter bypass network from between A4A8TPl and A4A8TP2.

41.Adjust A4A8C29 CTR to center signal on center graticule line. Adjust A4A8C13 SYM for best symmetry of signal. See Figure 3-44 for location of adjustments. If unable to adjust A4ABC13 SYM

for satisfactory signal symmetry, increase or decrease value of A4A8C14. Refer to Table 3-3 for range of values.

42.Press MARKER CPEAK SEARCH) and MARKER @

43.Key in [FREQUENCY SPAN] 10 kHz.

44.Key in [REsBW) 3 kHz and MARKER CPEAK SEARCH).

Adjustments 3-81

8.21.4 MHz Bandwidth Filter Adjustments

45.Adjust A4ABR40 XTAL to align markers on display. MARKER A level should indicate 1.00 X. See Figure 3-44 for location of adjustment.

LC Dip Adjustments

46.Refer to the Resolution Bandwidth Switching Uncertainty Performance Test, and check all bandwidth amplitudes. If amplitude of 300 kHz bandwidth is low but amplitude of 100 kHz and 1 MHz bandwidths are within tolerance, LC DIP adjustments must be performed. If all bandwidth amplitudes are within tolerance, do not perform the following adjustments.

47 . Set LINE switch to STANDBY.

48.Disconnect cable 97 (white/violet) from A4ABJl and connect to A4A6 J 1.

49.Remove A4A4 Bandwidth Filter and install on extenders.

50.Set LINE switch to ON. Press ~NSTR PRESET).

51.Key in [CENTER FREQUENCY] 20 MHz, [RES] 100 kHz,

~FREQUENCY SPAN] 1 MHz, [ATTEN) 0 dB, and LOG (ENTER dB/DIv] 2

dB.

52.Short A4A4TP3 to ground.

53.Adjust. A4A4C41 LC DIP for minimum amplitude of signal peak. See Figure 3-41 for location of adjustment. Key in CPEAK SEARCH) MARKER Ln], and adjust LC DIP again to offset the signal peak approximately -17 kHz (to the left). This is done to compensate for the effect of placing the board on extenders. If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4A4R16. Refer to Table 3-3 for range of values.

54.Remove short, from A4A4TP3 and short A4A4TP8 to ground.

55.Adjust A4A4C43 LC DIP for minimum amplitude of signal peak. See Figure 3-41 for location of adjustment. Key in [PEAK SEARCH) MARKER In], and adjust C43 LC DIP again to offset the signal peak approximately -17 kHz (to the left). If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4A4R60. Refer to lhble 3-3 for range of values.

56.Set LINE switch to STANDBY.

57.Reinstall A4A4 Bandwidth Filter without extenders. Short A4A4TP3 and A4A4TP8 to ground. Remove A4A8

Attenuator-Bandwidth Filter and install on extenders. Reconnect cable 97 to A4ABJl and reconnect cable 89 to A4A6Jl.

58.Set, LINE switch to ON. Press QNSTR PRESET).

59.Key in [CENTER FREQUENCY) 20 MHz, CRES] 100 kHz,

(FREQUENCY SPAN) 1 MHz, [ATTEN] 0 dB, and LOG (ENTER dB/DIV] 2 dB.

60.Short A4ABTP6 to ground.

61.Adjust A4ABC66 LC DIP for minimum amplitude of signal peak. See Figure 3-43 for location of adjustment. Key in CPEAK SEARCH) MARKER @, and adjust LC DIP again to offset the signal peak

3-82 Adjustments

8. 21.4 MHz Bandwidth Filter Adjustments

approximately -17 kHz (to the left). If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4ABR30. Refer to ???&ble 3-3 for range of values.

62.Remove short from A4ABTP6 and short A4ABTP3 to ground.

63.Adjust A4ABC67 LC DIP for minimum amplitude of signal peak. See Figure 3-43 for location of adjustment. Key in [PEAK SEARCH)

MARKER [nl, and adjust LC DIP again to offset the signal peak approximately -17 kHz (to the left). If unable to achieve a ???dip??? in signal amplitude, increase or decrease value of A4ABR55. Refer to ???Pdble 3-3 for range of values.

64.Set LINE switch to STANDBY.

65.Reinstall A4A8 Attenuator-Bandwidth Filter without extenders. Remove short. from A4ABTP3.

66.Set LINE switch to ON. Press ~NSTR PRESET].

67.Go back and repeat LC adjustments for both the A4A4 Bandwidth filter and the A4A8 Attenuator-Bandwidth Filter.

AlOdB and A20dB Adjustments

68.Set, step attenuators to 25 dB.

69.Key in ~CENTER FREQUENCY] 20 MHz, ~FREQUENCY SPAN_) 3 kHz, CATTEN] 0 dB, [REsBWI) 1 kHz, and [REFERENCE LEVEL) -30 dBm.

70.Key in LOG [ENTER dB/DIv] 1 dB then press MARKER (PEAK SEARCH) MARKER [nl

71.Key in [REFERENCE LEVEL) -20 dBm. Set step attenuators to 15 dB.

72.Adjust A4ABR7 AlOdB to align markers on display. MARKER A level should indicate 0.00 dB. See Figure 3-43 for location of adjustment.

73. Key in (REFERENCE LEVEL) -10 dBm. Set step attenuators to 5 dB.

74.Adjust A4ABR6 A2Od.B to align markers on display. MARKER A level should indicate 0.00 dB. See Figure 3-43 for location of adjustment.

Adjustments 3-83

9. 3 dB Bandwidth

Adjustments

Reference

Related Performance

Test

Description

Note

IF-Display Section

A4A9 IF Control

Resolution Bandwidth Accuracy Test

The CAL OUTPUT signal is connected to the RF INPUT. Each of the adjustable resolution bandwidths is selected and adjusted for the proper bandwidth at the 3 dB point.

Do not perform this adjustment on Option 462 instruments. Option 462 instruments require a different procedure. Adjustment 9 for Option 462 (6 dB or Impulse Bandwidth) is located in Chapter 4, Option 462.

Equipment

Procedure

No test equipment is required for this adjustment.

1.Position instrument upright and remove top cover.

2.Set LINE switch to ON and press (INSTR PRESET].

3.Connect CAL OUTPUT to RF INPUT.

4.Key in [CENTER FREQUENCY_) 20 MHz, (FREQUENCY SPAN) 5 MHz, LIN,

and (REs] 3 MHz.

5.Press PREFERENCE LEVEL] and adjust DATA knob to place signal peak near top CRT graticule line. Signal should be centered about the center line on the graticule. If not, press (PEAK SEARCH) and QEXTTF).

6.Press MARKER a.

7.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

8.Adjust A4A9R60 3 MHz for MKR A indication of 1.5 MHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See Figure 3-45 for location of adjustment.

3-84 Adjustments

9. 3 dB Bandwidth Adjustments

A4A9

IF CONTROL

\

A4A3

Figure 3-45. Location of 3 dB Bandwidth Adjustments

9.Press MARKER a. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X). There are now two markers; one on each side of the signal at the 3 dB points.

10.CRT MKR A annotation now indicates the 3 dB bandwidth of the 3 MHz bandwidth. 3 dB bandwidth should be 3.00 &to.60 MHz.

11.Key in @YWBW) 1 MHz and [FREQUENCY SPAN] 2 MHz. If necessary, readjust [REFERENCELEVEL)~CENTERand FREQUENCY), using DATA knob to place signal peak near top of graticule and centered on center graticule line.

12.Press MARKER [OFF), then MARKER @].

13.Using DATA knob, adjust marker down one side of displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

14.Adjust A4A9R61 1 MHz for MKR A indication of 500 kHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See Figure 3-45 for location of adjustment.

15.Press MARKER a. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X). There are now two markers; one on each side of the signal at the 3 dB point.

16.CRT MKR A annotation now indicates the 3 dB bandwidth of the 1 MHz bandwidth. 3 dB bandwidth should be 1.00 fO.10 MHz.

17.Key in @G?G-BW) 300 kHz and CFREQUENCY SPAN) 500 kHz. If necessary, readjust CREFERENCE LEVEL) and [CENTER FREQUENCY], using DATA knob to place signal peak near top of graticule and centered on center graticule line.

18.Press MARKER (OFF), then MARKER @J.

19.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

20.Adjust A4A9R62 300 kHz for MKR A indication of 150 kHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See

Figure 3-45 for location of adjustment.

2 1. Press MARKER [nl. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X).

Adjustments 3-85

9.3 dB Bandwidth Adjustments

22.CRT MKR A annotation now indicates the 3 dB bandwidth of the 300 kHz bandwidth. 3 dB bandwidth should be 300.0 f30.0 kHz.

23.Key in @GZVBW) 10 kHz and [FREQUENCY SPAN) 20 kHz. If necessary, readjust PREFERENCE LEVEL] and [CENTER FREQUENCY), using DATA knob to place signal peak near top of graticule and centered on center graticule line.

24.Press MARKER IOFF], then MARKER [ ].

25.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

26.Adjust A4A9R65 10 kHz for MKR A indication of 5.00 kHz while maintaining marker at 3 dB point (. 707 X) using DATA knob. See Figure 3-45 for location of adjustment.

27.Press MARKER A. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X).

28.CRT MKR A annotation now indicates the 3 dB bandwidth of the 10 kHz bandwidth. 3 dB bandwidth should be 10.0 fl.O kHz.

29.Key in (&YiGBW) 3 kHz and CFREQUENCY SPAN) 5 kHz. If necessary, readjust [REFERENCELEVEL) and [CENTER FREQUENCY], using DATA knob to place signal peak near top of graticule and centered on

center graticule line.

30.Press MARKER (OFF), then MARKER [nl.

31.Using DATA knob, adjust marker down one side of the displayed signal to the 3 dB point; CRT MKR A annotation indicates .707 X.

32.Adjust A4A9R66 3 kHz for MKR A indication of 1.5 kHz while maintaining marker at 3 dB point (.707 X) using DATA knob. See Figure 3-45 for location of adjustments.

33.Press MARKER [nl. Adjust marker to 3 dB point on opposite side of signal (CRT MKR A annotation indicates 1.00 X).

34.CRT MKR A annotation now indicates the 3 dB bandwidth of the 3 kHz bandwidth. 3 dB bandwidth should be 3.00 50.30 kHz.

3-86 Adjustments

10. Step Gain and

18.4 MHz Local

Oscillator

Adjustments

Reference

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

IF-Display Section

A4A7 3 MHz Bandwidth Filter

A4A5 Step Gain

Related Performance

Tests

Description

Resolution Bandwidth Selectivity Test

IF Gain Uncertainty Test

Center Frequency Readout Accuracy Test

First, the IF signal from the RF Section is measured with a power meter and adjusted for proper level. Next, the 10 dB gain steps are adjusted by connecting the CAL OUTPUT signal through two step attenuators to the RF INPUT and keying in the REFERENCE LEVEL necessary to activate each of the gain steps, while compensating for the increased gain with the step attenuators.

The 1 dB gain steps are checked in the same fashion as the 10 dB gain steps, and then the variable gain is adjusted. The 18.4 MHz oscillator frequency is adjusted to provide adequate adjustment range of front-panel FREQ ZERO control; and last, the + 1OV temperature compensation supply used by the A4A4 Bandwidth Filter and A4A8 Attenuator-Bandwidth Filter is checked and adjusted if necessary.

PMR METER

DIGITAL VOLTMETER

fi!&

1OdB S T E P 1 dB S T E P

ATTENUATOR ATTENUATOR

Figure 3-46.

Step Gain and 18.4 MHz Local Oscillator Adjustments Setup

Adjustments 3-87

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

Equipment Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8481A 10 dB Step Attenuator . . . . . . . . . . . . . . HP 355D, Option H89 1 dB Step Attenuator . . . . . . . . . . . . . . . HP 355C, Option H25

Procedure 1. Position instrument upright as shown in Figure 3-46 and remove top cover.

2.The validity of the results of this adjustment procedure is based in part on the performance of the Log Amplifiers, the Video Processor, and the Track and Hold. These adjustments must be done before proceeding with the adjustment procedure of the Step Gain and 18.4 MHz Local Oscillator.

3.Set instrument LINE switch to ON and press ~NSTR PRESET). Connect CAL OUTPUT to RF INPUT.

4.Key in [CENTER FREQUENCY] 20 MHz, [ R E F E R E N C E L E V E L ] - 1 0 dBm,

(ATTEN) 0 dB, [FREQUENCY SPAN) 0 Hz, [-BW) 1 kHz, l-1 100 Hz, and [SWEEP TIME) 20 ms.

IF Gain Adjustment

5.Disconnect cable 97 (white/violet) from A4A8Jl and connect cable to power meter/power sensor. Refer to Figure 3-47 for location of cable 97 and A4A8Jl.

6.Adjust front-panel AMPTD CAL adjustment for a power meter indication of -5 dBm.

7.Disconnect power meter and reconnect cable 97 to A4A8Jl.

8.Press LIN pushbutton and MARKER (-1.

9.Note MARKER amplitude in mV and adjust A45A5R33 CAL to

70.7mV (top CRT graticule line). See Figure 3-47 for location of adjustment.

R33

C A L

\-w

A4A5

Figure 3-47. Location of IF Gain Adjustment

3-88 Adjustments

10.Step Gain and 18.4 MHz Local Oscillator Adjustments

10.If A4A5R33 CAL adjustment does not have sufficient range to adjust trace to the top CRT graticule line, increase or decrease the value of A4A7R60 as necessary to achieve the proper adjustment range of A4A5 CAL adjustment. See Figure 3-39 for the location of A4A7R60. Refer to Table 3-3 for range of values for A4A7R60.

10 dB Gain Step Adjustment

11.Connect CAL OUTPUT to RF INPUT through 10 dB step attenuator and 1 dB step attenuator.

12.Key in LOG (ENTER dB/DIv] 1 dB and [REFERENCE LEVEL) -30 dBm.

13.Set step attenuators to 25 dB.

14.Key in MARKER A. Signal trace should be at the center CRT graticule line, and MKR A level, as indicated by CRT annotation, should be .OO dB.

15.Key in [REFERENCE LEVEL] -40 dBm. Set step attenuators to 35 dB.

16.Adjust A4A5R32 SGlO for MKR A level of .OO dB (CRT MKR A annotation is now in upper right corner of CRT display). See Figure 3-48 for location of adjustment.

A4A5 S T E P LAIN

A4A5

Figure 3-48. Location of 10 dB Gain Step Adjustments

17.If A4A5R32 SGlO adjustment does not have sufficient range to perform adjustment in step 16, increase or decrease the value of A4A7R60 as necessary to achieve the proper adjustment range of A4A5 SGlO. See Figure 3-39 for the location of A4A7R60. Refer to ???Ihble 3-3 for range of values for A4A7R60. Repeat steps 3 through 16 if the value of A4A7R60 is changed.

18.Key in [REFERENCE LEVEL] -50 dBm. Set step attenuators to 45 dB.

19.Adjust A4A5R44 SG20-1 for MKR A level of .OO dB. See

Figure 3-48 for location of adjustment.

20. Key in CREFERENCE LEVEL) -70 dBm. Set step attenuators to 65 dB.

21.Adjust A4A5R54 SG20-2 for MKR A level of .OO dB. See Figure 3-48 for location of adjustment.

Adjustments 3-89

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

1 dB Gain Step Checks

22.Key in [REFERENCE LEVEL) -19.9 dBm. Set step attenuators to 15 dB. Press MARKER @ twice to establish a new reference.

23.Key in (REFERENCE LEVEL) -17.9 dBm. Set step attenuators to 13 dB.

24.MKR A level, as indicated by CRT annotation, should be .OO f0.5 dB. If not, increase or decrease the value of A4A5R86. Refer to ???Ihble 3-3 for range of values.

25.Key in (REFERENCE LEVEL) -15.9 dBm. Set step attenuators to 11 dB.

26.MKR A level should be .OO ho.5 dB. If not, increase or decrease the value of A4A5R70. Refer to Table 3-3 for range of values.

27.Key in [REFERENCE LEVEL) -11.9 dBm. Set step attenuators to 7 dB.

28.MKR A level should be .OO ho.5 dB. If not, increase or decrease the value of A4A5R62. Refer to ???Ihble 3-3 for range of values.

.l dB Gain Step Adjustment

29. Key in LIN, (SHIFT) * (AUTO] (resolution bandwidth), and

(REFERENCE LEVEL) -19.9 dBm. Set step attenuators to 13 dB. Press MARKER (nl twice to establish a new reference.

30.Key in [REFERENCE LEVEL) -18.0 dBm. Set step attenuators to 11 dB.

31.Adjust A4A5R51 VR for MKR A level of + 0.10 dB. See Figure 3-49 for location of adjustment.

32.Remove all test equipment from the spectrum analyzer. Connect CAL OUTPUT to RF INPUT.

18.4MHz Local Oscillator Adjustment

33.Press ~NSTR PRESET] and IRECALL) @.

34.Set front-panel FREQ ZERO control to midrange.

35.Adjust A4A5ClO FREQ ZERO to peak signal trace on CRT. See Figure 3-49 for location of adjustment.

3.90 Adjustments

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

A4A5 S T E P G A I N

A4A5

Figure 3-49.

Location of .l dB Gain Step, 18.4 MHz LO, and + 1OV

Adjustments

36. Key in [FREQUENCY SPAN] 1kHz, [REs] 100 Hz, and

[PEAK SEARCH] a].

37.Adjust front-panel FREQ ZERO control fully clockwise. Press CPEAK SEARCH]. Signal should move at least 60 Hz away from center CRT graticule line.

38.Adjust front-panel FREQ ZERO control fully counterclockwise. Press [PEAK XEARCH]. Signal should move at least 60 Hz away from center CRT graticule line.

39.If proper indications are not achieved, increase or decrease value of A4A5C9 and repeat adjustment from step 33. Refer to Table 3-3 for range of values.

40.Press [INSTR PRESET) and IRECALL) @.

41.Adjust front panel FREQ ZERO to peak the signal trace on the CRT.

+ 1OV Temperature Compensation Supply Adjustment

42.Connect DVM to A4A5TPl (+ 1OVF).

43.If DVM indication is between +9 V dc and 10.0 V dc, no adjustment is required.

44.If DVM indication is not within tolerance of step 43, adjust A4A5R2 + 1OV ADJ for DVM indication of +9.5 ItO. V dc at

normal room temperature of approximately 25??C. Voltage change is approximately 30 mV/OC. Therefore, if room temperature is higher or lower than 25OC, adjustment should be made higher or lower, accordingly.

Adjustments 3-91

11. Down/Up

Converter

Adjustments

Reference

Related Performance

Test

Description

IF-Display Section

A4A6 Down/Up Converter

Resolution Bandwidth Switching Uncertainty Test

The CAL OUTPUT signal is connected to the RF INPUT connector of the instrument and controls are set to display the signal in a narrow bandwidth. A marker is placed at the peak of the signal to measure the peak amplitude. The bandwidth is changed to a wide bandwidth and the Down/Up Converter is adjusted to place the peak amplitude of the signal the same as the level of the narrow bandwidth signal.

Optionally, the input signal is removed and the IF signal is monitored at the output of the Bandwidth Filters using a spectrum analyzer with an active probe. The 18.4 MHz Local Oscillator and all harmonics are then adjusted for minimum amplitude.

HP 85024A

HIGH FREOUENCY PROBE

PWER SUPPLY

Equipment

Procedure

Figure 3-50. Down/Up Converter Adjustments Setup

Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8566B

Active Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85024A

1.Position Instrument upright as shown in Figure 3-50 and remove top cover.

2.Set LINE switch to ON and press (JNSTR PRESET].

3.Connect CAL OUTPUT to RF INPUT.

4.Key in [CENTER FREQUENCY) 20 MHz, (FREQUENCY SPAN) 10 kHz, [ATTEN)P 0 dB, [REs) 1 kHz. ress LIN pushbutton, [PEAK SEARCH), and then MARKER a.

5.Key in IJREsBW) 1 MHz.

3-92 Adjustments

11. Down/Up Converter Adjustments

6.Adjust A4A6AlR29 WIDE GAIN to align markers on CRT display. MKR A level should indicate 1.00 X. See Figure 3-51 for location of adjustment.

7.Disconnect CAL OUTPUT from RF INPUT.

Optional

1.Disconnect CAL OUTPUT from RF INPUT.

2.Key in [REFERENCE LEVEL) -70 dBm, [REs] 1 kHz, and MARKER IOFF).

3.Set the second spectrum analyzer???s to the following settings:

RESOLUTION BANDWIDTH . . . . . . . . . . . . . . . . . . 100 kHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 MHz

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . 18.4 MHz

RF ATTENUATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 dB

REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 dBm

SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LOG 10 dB/div

4.Connect the second spectrum analyzer to A4A4TP7 using and active probe. See Figure 3-50 for test setup.

5.Adjust A4A6AlC31 18.4 MHz NULL to null the 18.4 MHz Local Oscillator signal and all displayed harmonics. See Figure 3-51 for location of adjustment.

Figure 3-51. Location of Down/Up Converter Adjustments

6.18.4 MHz signal and displayed harmonics should be below -10 dBm (-30 dBm on display due to 1O:l divider). If unable to adjust A4A6AlC31 18.4 MHz NULL for proper indication, increase value of A4A5RlO. See Figure 3-49 for the location of A4A5RlO. Refer to ???Iable 3-3 for range of values.

Adjustments 3-93

11. Down/Up Converter Adjustments

Down Converter Gain

Adjustment

Note

If a gain problem is suspected in the 10 Hz to 1 kHz resolution bandwidths, perform the following procedure to test and adjust the gain through A4A6A2.

1.Place A4A6 on extender boards.

2.On the spectrum analyzer being tested, press QNST PRESET], and set the spectrum analyzer to the following settings:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . . . 20 MHz RESOLUTION BANDWIDTH . . . . . . . . . . . . . . . . . . . . . 1 kHz FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Hz REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . . . . . -10 dBm INPUT ATTENUATION . . . . . . . . . . . . . . . . . . . . . . . . . . 10 dB

3.Connect an active probe to a second spectrum analyzer, and set the spectrum analyzer to the following settings:

CENTER FREQUENCY . . . . . . . . . . . . . . . . . . . . . . 21.4 MHz

RESOLUTION BANDWIDTH . . . . . . . . . . . . . . . . . . 100 kHz

FREQUENCY SPAN . . . . . . . . . . . . . . . . . . . . . . . . . . ..200 Hz

REFERENCE LEVEL . . . . . . . . . . . . . . . . . . . . _ . . . -30 dBm

INPUT ATTENUATION . . . . . . . . . . . . . . . . . . . . . . . . . . 10 dB

SCALE . . . . . . . . . . . . . . . . . _ . . . . . . . . . . . . . . . LOG 1 dB/div

4.Measure the signal at A4A6A2TP4 using the active probe and record below. The signal level should be approximately -33 dBm.

5.Change the center frequency of the spectrum analyzer used for measuring the signals to 3 MHz. Measure the signal at

A4A6A2Pl-9. The signal level should be 10 dB f0.6 dB lower than the signal measured in the previous step.

6.If the signal at A4A6A2Pl-9 needs adjusting, change A4A6A2R33. (Decreasing R33 ten percent increases the signal level by 0.6

dB.) Refer to Table 3-3 for the acceptable range of values for A4A6A2R33.

3-94 Adjustments

12.Time Base Adjustment (SN 2840A and Below, also 3217A05568 and Above)

12.Time Base

Adjustment (SN 2840A and Below, also 3217AO5568 and Above)

Reference

Related Performance

Test

Description

RF Section:

A27Al 10 MHz Quartz Crystal Oscillator

Center Frequency Readout Accuracy Test

The frequency of the internal 10 MHz Frequency Standard is compared to a known frequency standard and adjusted for minimum frequency error. This procedure does not adjust the short-term stability or long-term stability of the 10 MHz Quartz Crystal Oscillator, which are determined by characteristics of the particular oscillator and the environmental and warmup conditions to which it has been recently exposed. The spectrum analyzer must be ON continuously (not in STANDBY) for at least 72 hours immediately prior to oscillator adjustment to allow both the temperature and frequency of the oscillator to stabilize.

1

Figure 3-52. Time Base Adjustment Setup

Equipment Frequency Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 5061B Frequency Counter . . . . . . . . . . . . . . . . . . . . . . . . . HP 5334A/B

Cables:

BNC cable, 122 cm (48 in) (2 required) . . . . . . . . HP 10503A

Adjustments 3-95

12. Time Base Adjustment (SN 2840A and Below, also 3217A05568 and Above)

Procedure

Note

Note

The spectrum analyzer must be ON continuously (not in STANDBY) for at least 72 hours immediately prior to oscillator adjustment to allow both the temperature and frequency of the 10 MHz Quartz Crystal Oscillator to stabilize. Adjustment should not be attempted before the oscillator is allowed to reach its specified aging rate. Failure to allow sufficient stabilization time could result in oscillator misadjustment.

The A27Al 10 MHz Quartz Crystal Oscillator (HP P/N 0960-0477) will typically reach its specified aging rate again within 72 hours after being switched off for a period of up to 24 hours. If extreme environmental conditions were encountered during storage or

shipment (i.e. mechanical shock, temperature extremes) the oscillator could require up to 30 days to achieve its specified aging rate.

1.Set the rear-panel FREQ REFERENCE switch on the spectrum analyzer RF Section to INT.

The +22 Vdc STANDBY supply provides power to the heater circuit in the A27 10 MHz Frequency Standard assembly whenever line power is applied to the RF Section. This allows the A27 10 MHz Frequency Standard oven to remain at thermal equilibrium, minimizing

frequency drift due to temperature variations. The OVEN COLD message should typically appear on the spectrum analyzer display for 10 minutes or less after line power is first applied to the RF Section.

Note The rear-panel FREQ REFERENCE switch enables or disables the RF Section +20 Vdc switched supply, which powers the oscillator circuits in the A27 10 MHz Frequency Standard. This switch must be set to INT and the spectrum analyzer must be switched ON continuously (not in STANDBY) for at least 72 hours before adjusting the frequency of the A27 10 MHz Frequency Standard.

2.Set the LINE switch to ON. Leave the spectrum analyzer ON (not in STANDBY) and undisturbed for at least 48 hours to allow the temperature and frequency of the A27 10 MHz Frequency Standard to stabilize.

3.Press (SHIFT) TRACE B [CLEAR-WRITE] g to turn off the display. This prolongs CRT life while the spectrum analyzer is unattended. To turn the CRT back on press m TRACE B C-HOLD) h.

4.Connect the (Cesium Beam) Frequency Standard to the Frequency Counter???s rear-panel TIMEBASE IN/OUT connector as shown in Figure 3-52.

5.Disconnect the short jumper cable on the RF Section rear panel from the FREQ REFERENCE INT connector. Connect this output (FREQ REFERENCE INT) to INPUT A on the Frequency Counter. A REF UNLOCK message should appear on the CRT display.

3.96 Adjustments

12. Time Base Adjustment (SN 2840A and Below, also 3217A05568 and Above)

6. Set the Frequency Counter controls as follows:

INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A ATTENUATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .x10 DC Coupled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OFF 1 Mdl input impedance . . . . . . . . . . . . . . . . . . . . . . . . . . OFF AUTOTRIG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ON 100 kHz FILTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OFF INT/EXT switch (rear panel) . . . . . . . . . . . . . . . . . . . . . EXT

7.On the Frequency Counter, select a 10 second gate time by pressing, [GATE] 10 [GATE).

8.Offset the displayed frequency by -10.0 MHz by pressing,

MATH CSELECT/ENTER) C-1 10 [CHS/EEX) 6 [SELECT/ENTER)

SELECT/ENTER]. The Frequency Counter should now display the difference between the frequency of the INPUT A signal (A27 10 MHz Frequency Standard) and 10.0 MHz with a displayed resolution of 1 mHz (0.001 Hz).

9.Wait at least two gate periods for the Frequency Counter to settle, and record the frequency of the A27 10 MHz Frequency Standard as reading #l.

10.Allow the spectrum analyzer to remain powered (not in STANDBY) and undisturbed for an additional 24 hours.

11.Repeat steps 3 through 7 and record the frequency of the A27 10 MHz Frequency Standard as reading #2.

12.If the difference between reading #2 and reading #l is greater than 1 mHz, the A27 10 MHz Frequency Standard has not achieved its specified aging rate; the spectrum analyzer should remain powered (not in STANDBY) and undisturbed for an additional 24-hour interval. Then, repeat steps 3 through 7, recording the frequency of the 10 MHz Frequency Standard at the end of each 24-hour interval, until the specified aging rate of 1 mHz/day (lxlOES/day) is achieved.

13.Position the spectrum analyzer on its right side as shown in Figure 3-52 and remove the bottom cover. Typically, the frequency of the A27 10 MHz Frequency Standard will shift

slightly when the spectrum analyzer is reoriented. Record this shifted frequency of the A27 10 MHz Frequency Standard.

Adjustments 3-97

12. Time Base Adjustment (SN 2840A and Below, also 3217A05568 and Above)

14.Subtract the shifted frequency reading in step 11 from the last recorded frequency in step 10. This gives the frequency correction factor needed to adjust the A27 10 MHz Frequency Standard.

15.On the Frequency Counter, select a 1 second gate time bv

pressing, ~~~ 1 @kiK]. The Frequency Counter should now display the difference between the frequency of the INPUT A signaland 10.0 MHz with a resolution of 0.01 Hz (10 mHz).

16.Remove the two adjustment cover screws from the A27 10 MHz Quartz Crystal Oscillator. See Figure 3-53 for the location of the A27 10 MHz Frequency Standard.

Note Do not use a metal adjustment tool to tune an oven-controlled

crystal oscillator (OCXO). The metal will conduct heat away from the oscillator circuit, shifting the operating conditions.

17.Use a nonconductive adjustment tool to adjust the 18-turn FREQ ADJ capacitor on the A27Al 10 MHz Quartz Crystal Oscillator for a Frequency Counter indication of 0.00 Hz. See Figure 3-53 for the location of the A27Al 10 MHz Quartz Crystal Oscillator.

R F S e c t i o n ( b o t t o m view)

A27Al

Figure 3-53. Location of A27Al Adjustment

18.On the Frequency Counter, select a 10 second gate time by pressing, [GATE) 10 [GATE). The Frequency Counter should now display the difference between the frequency of the INPUT A signal and 10.0 MHz with a resolution of 0.001 Hz (1 mHz).

19.Wait at least 2 gate periods for the Frequency Counter to settle, and then adjust the 16-turn FINE adjustment on the A27 10 MHz Frequency Standard for a stable Frequency Counter indication of (0.000 + Frequency Correction Factor) fO.O1O Hz.

20.Replace the RF Section bottom cover and reconnect the short jumper cable between the FREQ REFERENCE INT and EXT connectors,

3-98 Adjustments

12. Time Base Adjustment (SN 2848A to 3217A05567)

12. Time Base

Adjustment (SN

2848A to

3217A05567)

Reference

Related Performance

Test

Description

RF Section:

A27Al Frequency Standard Regulator

A27A2 10 MHz Quartz Crystal Oscillator

Center Frequency Readout Accuracy Test

The frequency of the internal 10 MHz Frequency Standard is compared to a known frequency standard and adjusted for minimum frequency error. This procedure does not adjust the short-term stability or long-term stability of the 10 MHz Quartz Crystal Oscillator, which are determined by characteristics of the particular oscillator and the environmental and warmup conditions to which it has been recently exposed. The spectrum analyzer must be ON continuously (not in STANDBY) for at least 72 hours immediately prior to oscillator adjustment to allow both the temperature and frequency of the oscillator to stabilize.

14FREPUENCY STANDARD

Figure 3-54. Time Base Adjustment Setup

Equipment Frequency Standard . . . . . . . . . . . . . . . . . . . . . . . . HP 5061A/B Frequency Counter . . . . . . . . . . . . . . . . . . . . . . . . . HP 5334A/B

Cables:

BNC cable, 122 cm (48 in) (2 required) . . . . . . . . HP 10503A

Procedure

Note The spectrum analyzer must be ON continuously (not in STANDBY) for at least 72 hours immediately prior to oscillator adjustment. This allows both the temperature and frequency of the oscillator to

stabilize. Adjustment should not be attempted before the oscillator is allowed to reach its specified aging rate. Failure to allow sufficient stabilization time could result in oscillator misadjustment.

Adjustments 3-99

12. Time Base Adjustment (SN 2848A to 3217A05567)

Note

Note

The A27A2 10 MHz Quartz Crystal Oscillator (HP P/N 1081 l-601 11) typically reaches its specified aging rate again within 72 hours after being switched off for a period of up to 30 days, and within 24 hours after being switched off for a period less than 24 hours. If extreme environmental conditions were encountered during storage or shipment (i.e. mechanical shock, temperature extremes) the oscillator could require up to 30 days to achieve its specified aging rate.

Replacement oscillators are factory-adjusted after a complete warmup and after the specified aging rate has been achieved. Readjustment should typically not be necessary after oscillator replacement, and is generally not recommended.

1.Set the rear-panel FREQ REFERENCE switch on the spectrum analyzer RF Section to INT.

The + 22 Vdc STANDBY supply provides power to the heater circuit in the A27 10 MHz Frequency Standard assembly whenever line power is applied to the RF Section. This allows the A27 10 MHz Frequency Standard oven to remain at thermal equilibrium, minimizing

frequency drift due to temperature variations. The OVEN COLD message should typically appear on the spectrum analyzer display for 10 minutes or less after line power is first applied to the RF Section.

The rear-panel FREQ REFERENCE switch enables or disables the RF Section +20 Vdc switched supply, which powers the oscillator circuits in the A27 10 MHz Frequency Standard. This switch must be set to INT and the spectrum analyzer must be switched ON continuously (not in STANDBY) for at least 72 hours before adjusting the frequency of the A27 10 MHz Frequency Standard.

2.Set the LINE switch to ON. Leave the spectrum analyzer ON (not in STANDBY) and undisturbed for at least 48 hours to allow the temperature and frequency of the A27 10 MHz Frequency Standard to stabilize.

3.Press [ml TRACE B (CLEAR-WRITE) g to turn off the display. This prolongs CRT life while the spectrum analyzer is unattended. To turn the CRT back on press (SHIFT] TRACE B (MAX HOLD)h.

4.Connect the (Cesium Beam) Frequency Standard to the Frequency Counter???s rear-panel TIMEBASE IN/OUT connector as shown in Figure 3-54.

5.Disconnect the short jumper cable on the RF Section rear panel from the FREQ REFERENCE INT connector. Connect this output (FREQ REFERENCE INT) to INPUT A on the Frequency Counter. A REF UNLOCK message should appear on the CRT display.

6.Set the Frequency Counter controls as follows:

3-100 Adjustments

12. Time Base Adjustment (SN 2848A to 3217A05567)

INT/EXT switch (rear panel) . . . . . . . . . . . . . . . . . . . . . EXT

7.On the Frequency Counter, select a 10 second gate time by pressing, (GATETIME_) 10 (GATE].

8.Offset the displayed frequency by -10.0 MHz by pressing,

MATH (SELECT/ENTER] Cm) 10 I-1 6 [SELECT/E~&ER]

(SELECT/ENTER). The Frequency Counter should now display the difference between the frequency of the INPUT A signal (A27 10 MHz Frequency Standard) and 10.0 MHz with a displayed resolution of 1 mHz (0.001 Hz).

9.Wait at least two gate periods for the Frequency Counter to settle, and record the frequency of the A27 10 MHz Frequency Standard as reading #l.

Note The A27A2 Quartz Crystal Oscillator has a typical adjustment range of 10 MHz *lO Hz. The oscillator frequency should be within this range after 48 hours of continuous operation.

10.Allow the spectrum analyzer to remain powered (not in STANDBY) and undisturbed for an additional 24 hours.

11.Repeat steps 3 through 7 and record the frequency of the A27 10 MHz Frequency Standard as reading #2.

12. If the difference between reading #2 and reading #l is greater than 1 mHz, the A27 10 MHz Frequency Standard has not achieved its specified aging rate; the spectrum analyzer should remain powered (not in STANDBY) and undisturbed for an additional 24-hour interval. Then, repeat steps 3 through 7, recording the frequency of the 10 MHz Frequency Standard at the end of each 24-hour interval, until the specified aging rate of 1 mHz/day (lxlOE9/day) is achieved.

13.Position the spectrum analyzer on its right side as shown in Figure 3-54 and remove the bottom cover. Typically, the frequency of the A27 10 MHz Frequency Standard will shift

slightly when the spectrum analyzer is reoriented. Record this shifted frequency of the A27 10 MHz Frequency Standard.

14.Subtract the shifted frequency reading in step 8 from the last recorded frequency in step 7. This gives the frequency correction factor needed to adjust the A27 10 MHz Frequency Standard.

Adjustments 3-101

12.Time Base Adjustment (SN 2848A to 3217A05567)

15.On the Frequency Counter, select a 1 second gate time by

pressing, t-1 1 @Y%YiK]. The Frequency Counter should now display the difference between the frequency of the INPUT A signal and 10.0 MHz with a resolution of 0.01 Hz (10 mHz).

Note Do not use a metal adjustment tool to tune an oven-controlled crystal oscillator (OCXO). The metal will conduct heat away from the oscillator circuit, shifting the operating conditions.

16.Use a nonconductive adjustment tool to adjust the 18-turn FREQ ADJ capacitor on the A27A2 10 MHz Quartz Crystal Oscillator for a Frequency Counter indication of 0.00 Hz. See Figure 3-55 for the location of the A27A2 10 MHz Quartz Crystal Oscillator.

R F S e c t i o n ( b o t t o m view)

Figure 3-55. Location of A27A2 Adjustment

17.On the Frequency Counter, select a 10 second gate time by pressing, [GATETIME) 10 C-1. The Frequency Counter should now display the difference between the frequency of the INPUT A signal and 10.0 MHz with a resolution of 0.001 Hz (1 mHz).

18.Wait at least 2 gate periods for the Frequency Counter to settle, and then adjust the FREQ ADJ capacitor on the A27A2 10 MHz Quartz Crystal Oscillator for a stable Frequency Counter indication of (0.000 + Frequency Correction Factor) fO.O1O Hz.

19.Replace the RF Section bottom cover and reconnect the short jumper cable between the FREQ REFERENCE INT and EXT connectors.

3-102 Adjustments

13. 20 MHz Reference Adjustments

13. 20 MHz

Reference

Adjustments

Reference

Related Performance

Test

Description

RF Section:

Al6 20 MHz Reference

Calibrator Amplitude Accuracy Test

The 20 MHz output is peaked and amplitude checked for proper level. The INTERNAL REFERENCE output level is then checked for proper output level as compared to input from A27 Time Base. Finally, the COMB DRIVE and CAL OUTPUT are adjusted for proper power levels.

SPECTRUM ANALYZER

SYNTHESIZER LEVEL

GENERAT 6R

0)I

POWER METER

DIGITAL VOLTMETER

(Devise Under Teat)

Figure 3-56. 20 MHz Reference Adjustments Setup

Equipment Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . HP 8566A/B Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A

Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A

Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP8482

Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A

1O:l Divider Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10432A

Adapters:

Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . . 1250-0780

Type N (f) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . . . 1250-1474

Cables:

BNC to SMB cable Snap-On (2 required) . . . . . . 85680-60093

Adjustments 3-103

13. 20 MHz Reference Adjustments

Procedure 1. Position instrument on right side as shown in Figure 3-56 and remove bottom cover. Remove Al6 20 MHz Reference and install on extenders. See Figure 3-57 for the location of Al6 components.

2.Set LINE switch to ON and press (INSTR PRESET).

3.Set rear-panel FREQ REFERENCE INT/EXT switch to INT. Disconnect cable 2 (red) from A16Jl. Connect power meter to output of Time Base (A27Jl) using cable 2 (red). Note power meter indication for reference later.

dBm

4.Reconnect A27 Time Base output to A16Jl.

5.JumDer A16TP4 to Ground. Set the HP 8566A/B Spectrum Analyzer to [CENTER FREQUENCY) 20 MHz, [FREQUENCY SPAN) 1 MHz,

CREFERENCE LEVEL) +20 dBm, and (RES] 100 kHz. Connect A16J3 to RF INPUT of HP 8566A/B Soectrum Analyzer and set [REFERENCE LEVEL) to place of signal at reference line (top graticule line).

6.Set HP 8566A/B Spectrum Analyzer to 1 dB/division SCALE and reset reference level to place peak of signal at reference line.

7.Connect DVM to A16TPl and ground to A22 TP12. Adjust Al6 COMB DRIVE A16R31 for DVM indication of > + 0.1 V dc.

Disconnect DVM. (If DVM remains connected, it may load circuit.) See Figure 3-57 for location of adjustment.

Al6 20MHz R E F E R E N C E

\,

Figure 3-57. Location of 20 MHz Reference Adjustments

8.Adjust Al6 DOUBLER A16Tl to lower signal peak approximately 3 dB. Adjust Al6 CENTER FREQ A16Cll to peak signal on HP 8566A/B Spectrum Analyzer display. Next, adjust Al6 DOUBLER A16Tl for signal peak.

9.Disconnect cable 2 (red) from A16Jl and connect 500 OUTPUT of frequency synthesizer to A16Jl. Set FREQUENCY of frequency synthesizer to 10.17 MHz and set AMPLITUDE to + 3 dBm. Set HP

3-104 Adjustments

13. 20 MHz Reference Adjustments

8566AB Spectrum Analyzer (CENTER FREQUENCY_) to 20.34 MHz and SCALE to 10 dB/division.

10.Adjust Al6 20.34 MHz NULL A16C12 for minimum 20.34 MHz signal at A16J3 as indicated by HP 8566A/B Spectrum Analyzer display. With signal nulled, the plates of the NULL adjustment

capacitor should be meshed approximately halfway. If fully meshed or fully unmeshed, a circuit malfunction is indicated.

11. Disconnect frequency synthesizer from A16Jl and reconnect cable 2 (red) to A16Jl. Connect power meter to rear-panel INT REF OUT connector.

12.Power meter indication should be no more than 5 dB less than that noted in step 3 (A27 Time Base output).

13.Disconnect A16TP4 from ground. Connect power meter to A16J3.

14.Adjust Al6 COMB DRIVE A16R31 for power meter indication of

+10.0 dBm +l.O dB.

15.Connect power meter to A16J4 through cable 3 (orange). Power meter indication should be at least -15 dBm. Reconnect cable 3 (orange) to A6J2.

16.Connect power meter to A16J5 through cable 4 (yellow). Power meter indication should be at least -10 dBm. Reconnect cable 4 (yellow) to A8Jl.

17.On the oscilloscope, key in [RECALL) [mj to perform a soft reset.

18.Connect the channel 1 probe to the oscilloscope???s rear panel PROBE COMPENSATION AC CALIBRATOR OUTPUT connector. Press [AUTO SCALE). Adjust the channel 1 probe for an optimum square wave display on the oscilloscope.

19.Connect oscilloscope with the HP 10432A probe to A16TP3 and the ground to the analyzer???s chassis ground.

20.Set the oscilloscope controls as follows:

Adjustments 3-105

13. 20 MHz Reference Adjustments

Press &K?@

Press CnTavj:

AVmarkers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..on

Vmarker 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800mv

Vmarker2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..2.7V

start marker . . . . . . . . . . . . . . . . . place at 2.7V crossing

stop marker . . . . . . . . . . . . . place at next 2.7V crossing

2 1. Oscilloscope display should be a 10 MHz signal of TTL level; less than +0.8V to greater than +2.7V. See Figure 3-58 for a typical signal.

1 f800.0mV

Figure 3-58. Typical Signal at A16TP3

22.Install Al6 20 MHz Reference without extenders and reconnect cable 7 (violet) to A16J3.

23.Connect power meter to front-panel CAL OUTPUT.

24.Adjust A26 CAL LEVEL A16R51 for power meter indication of -10.0 dBm f0.2 dB.

25.the A23A6 Comb Generator must be readjusted after adjusting the 20 MHz Reference. Refer to Adjustments 22, Comb Generator Adjustments, for adjustment procedure.

3-106 Adjustments

14. 249 MHz Phase

Lock Oscillator

Adjustments

Reference

Description

14. 249 MHz Phase Lock Oscillator Adjustments

RF Section:

A7 249 MHz Phase Lock Oscillator

Two center frequencies are chosen: one which will tune the 249 MHz Oscillator to its low-end frequency and one which will tune the 249 MHz Oscillator to the high-end frequency. The voltage is monitored with a DVM at the output of the oscillator, and the oscillator frequency is adjusted to produce the proper dc voltage output for each frequency (low-end and high-end). Next, the 500 kHz Trap is adjusted to null the 500 kHz sidebands using the sixth harmonic of the 249 MHz signal.

SPECTRLM ANALYZER

J

Figure 3-59. 249 MHz Phase Lock Oscillator Adjustments Setup

Equipment Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . HP 8566A/B Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8447F Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A Tee, SMB Male . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 1250-0670

Adapters:

Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . . . . 1250-1250

Cables:

BNC cable, 122 cm (48 in) (2 required) . . . . . . . . . . . . 10503A

BNC to SMB Snap-On cable (2 required) . . . . . . 85680-60093

Adjustments 3-107

14. 249 MHz Phase Lock Oscillator Adjustments

Procedure 1. Place instrument on right side with IF-Display Section facing right as shown in Figure 3-59.

2.Set LINE switch to ON and press QNSTR PRESET].

3.Connect DVM to A7TPl and ground to A22TP12.

4.Key in [CENTER FREQUENCY) 17.6 MHz and [FREQUENCY SPAN) 0 Hz

on HP 8568B.

5.Adjust A7 PLO A7C3 for DVM indication between +5.2 V dc and +6.0 V dc. See Figure 3-60 for location of adjustment.

A7 2 4 9 M H z

P H A S E L O C K O S C I L L A T O R

Figure 3-60.

Location of 249 MHz Phase Lock Oscillator Adjustments

6.Key in ~CENTER FREQUENCY] 37.1 MHz.

7.DVM indication should be between + 12.9 V dc and + 16.9 V dc. If DVM indication is within the given range, disconnect DVM from A7TPl and proceed to step 18. Otherwise, key in CRAVE_) 2, SET LINE switch to STANDBY, and place A7 249 MHz PLO on extender (with DVM still connected to A7TPl).

8.Set LINE switch to ON and key in [RECALL_) 2 on HP 8568B S p e c t r u m A n a l y z e r .

9.Adjust A7 PLO A7C3 for DVM indication of + 13.0 ho.1 V dc.

10.Key in [CENTER FREQUENCY) 17.6 MHz, CFREQUENCY SPAN] 0 Hz, and [SAVE_) 1.

11.Adjust A7 PLO A7L2 for DVM indication of +5.2 f0.05 V dc. (A7L2 slug should be near center of coil form when A7L2 is properly adjusted.)

12.Key in [=J 2 and adjust A7C3 for + 13.0 fO.l V dc at A7Pl.

13.Press 1 (RECALL 1) and adjust A7L2 for +5.2 rtO.05 V dc.

14.Repeat steps 12 and 13 until A7C3 and A7L2 need no further adjustment.

3-108 Adjustments

14.249 MHz Phase Lock Oscillator Adjustments

15.Set LINE switch to STANDBY. Adjust A7L2 one-half turn counterclockwise before placing A7 249 MHz PLO in HP 8568B Spectrum Analyzer without extender. (Leave DVM connected to A7TPl).

16.Set LINE switch to ON and key in @KKK) 1. DVM indication should be between +5.2 V dc and +6.0 V de.

17.Press 2 (RECALL 2). DVM indication should be between + 12.9 V dc and + 16.9 V dc. Disconnect DVM from A7TPl.

18.Set LINE switch to STANDBY and place A7 249 MHz PLO on extender.

19.Set LINE switch to ON, press ~NSTR PRESET), and set the analyzer as follows:

20.Disconnect cable from A7Jl and connect cable 89 (gray/white) to one branch of a tee. Using a short coaxial cable (see Note below), connect the other branch of the tee back to A7Jl. Connect the stem of the tee to the HP 8566A/B Spectrum Analyzer RF INPUT.

Note The short cable 9 (white) in the IF-Display Section (A3A9J2 to A3A2Jl) can be disconnected and used for this adjustment. Be sure to reconnect the cable 9 (white) when finished.

21. Press @?G?iG] on the HP 8566A/B Spectrum Analyzer and key in (FREQUENCY SPAN) 5 MHz, [CENTER FREQUENCY) 1547 MHz, SPEAK SEARCH) and t-1.

22. On the HP 8566A/B Spectrum Analyzer, key in [SIGNAL TRACK),

[FREQUENCY SPAN) 10 kHz, cm) 300 Hz, [REFERENCE LEVEL)

-50 dBm, and CATTEN] 0 dB.

23.On the HP 8566A/B Spectrum Analyzer, turn off [SIGNAL TRACK_] and set [CF STEP SIZE) to 500 kHz on the HP 8566A/B Spectrum Analyzer. Press [CENTER FREQUENCY), then a key.

24.Disconnect cable from the HP 8566A/B Spectrum Analyzer RF INPUT and connect cable (from tee) to PRE AMP input of HP 8447F Amplifier. Connect cable from PRE AMP output to the HP 8566A/B Spectrum Analyzer RF INPUT.

25.Adjust A7 500 kHz TRAP adjustments A7L15 and A7L17 to null the 500 kHz sideband displayed on the spectrum analyzer. The 500 kHz sideband should be less than -90 dBm. See Figure 3-60 for location of adjustments.

26.Press (SAVE_) 1 on HP 8568B Spectrum Analyzer. Set LINE switch to STANDBY and place A7 249 MHz PLO in HP 8568B Spectrum Analyzer without extender (leave tee connected).

27.Set LINE switch to ON and press CRECALL) 1. Verify that 500 kHz remains less than -90 dBm in amplitude.

28.Disconnect tee and reconnect cable 89 (gray/white) to A7J 1.

Adjustments 3-l 09

15. 275 MHz Phase Lock Oscillator Adjustment

Figure 3-62. Location of 275 MHz PLO Adjustment

7. Disconnect test equipment from instrument.

Adjustments 3-l 11

16. Second IF

Amplifier and

Third Converter

Adjustment

Reference

Description

RF Section:

A19 Second IF Amplifier

A20 Third Converter

A synthesized sweeper is used to inject a signal of 301.4 MHz at -20 dBm in to the A19 Second IF Amplifier. The output of the amplifier is displayed on a scalar network analyzer. The amplifier is adjusted for a bandpass of greater than 7 MHz and less than 14 MHz centered at 301.4 MHz. Its gain should be greater than 14 dB and less than 17

dB. A spectrum analyzer is used to view the output of the 280 MHz Oscillator on the A20 Third Converter and the oscillator is centered in its adjustment range.

SPECTRLM ANALYZE

SYNTHESIZED WEEPER

NETWORK ANALYZER

Figure 3-63. Second IF Amplifier Adjustments Setup

Equipment Spectrum Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . HP 8566A/B Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A/B Scalar Network analyzer . . . . . . . . . . . . . . . . . . . . . . . HP 8757A Power Splitter . . . . . . . . . . . . . . . . . . . . . . HP 11667A Opt. 001 PowerMeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8482A Detector (2 required) . . . . . . . . . . . . . . . . . . . . . . . . . HP 11664A 20 dB Attenuator . . . . . . . . . . . . . . . . . . . . HP 8491A, Opt. 020

3-112 Adjustments

Procedure

Second IF Amplifier

Adjustments

16. Second IF Amplifier and Third Converter Adjustment

Adapters:

Type N (f) to APC-3.5 (f) . . . . . . . . . . . . . . . . . . . . . . 1250-1745 Type N (m) to BNC (f) (2 required) . . . . . . . . . . . . . 1250-0780 Type N (f) to BNC (f) (2 required) . . . . . . . . . . . . . . 1250-1474 APC 3.5 (f) to APC 3.5 (f) . . . . . . . . . . . . . . . . . . . . . 1250-1749

Cables:

BNC to SMB Snap-On (Service Accessory) (2 required) . 85680-60093

BNC 122 cm (48 in) (3 required) . . . . . . . . . . . . . . . . . . 10503A SMA (m) to (m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5061-5458

1.Position instrument on right side as shown in Figure 3-63, with bottom cover removed.

2.Set LINE switch to ON and press QNST PRESET] on HP 8568B, HP 8566A/B, HP 8757A, and HP 8340A/B.

3.Connect 20 dB Attenuator and power splitter to RF OUTPUT of synthesized sweeper. Connect one arm of power splitter to R input of scalar network analyzer through Detector. See Figure 3-63.

4.Set synthesized sweeper FREQUENCY MARKERS IIv11) to 291.4 MHz and (M2) to 311.4 MHz.

5.Press [cwl301.4 MHz on synthesized sweeper.

6.Connect Power meter to other power splitter port and set synthesized sweeper [POWER LEVEL) for Power Meter indication of -20.0 60.1 dBm.

7.Disconnect Power Meter and connect power splitter output to A19J1, using adapter and a BNC to SMB test cable. Refer to Figure 3-64.

8.Connect A19J2 to A input of scalar network analyzer, using adapter and another BNC to SMB test cable.

9.Connect synthesized sweeper SWEEP OUTPUT (rear panel), Z-AXIS BLANK/MKRS (rear panel), and PULSE MODULATION INPUT to proper rear-panel connectors on scalar network Analyzer, as shown in Figure 3-63.

10.On the scalar network analyzer, turn Channel 2 off and press IIVIEAS) (A/R).

11.Set scalar network analyzer [mj to 1 dB and set m (RF LEVEL) to + 14 dB. Set REF POSN (press REF POSN) to the fourth division from bottom using the data knob.

12.On synthesized sweeper, press [ml (ON) (MKR???, and IaF]. Set [SWEEP TIME] to 500 ms.

13.Adjust A19 301.4 MHz Bandpass Filter, A19C9 through C12, for the best bandpass filter response with a gain of > + 14 dBm but < + 17 dBm. See Figure 3-64 for the location of the bandpass adjustments.

Adjustments 3-l 13

16. Second IF Amplifier and Third Converter Adjustment

See Figure 3-65 for the typical response when the bandpass filter is properly adjusted.

14.On the scalar network analyzer, press @CEEQ MAX. Press cursor A, ON and set the cursor to the -3 dB point on the low side of the filter response (ho.1 dB).

15.Press cursor A and set the cursor to the -3 dB point on the high side on the filter response. The cursor A should read 0 fO.l dB.

A19

Ll

A M P T D

A20

Figure 3-64.

Location of 301.4 MHz BPF and 280 MHz AMPTD Adjustments

Figure 3-65.

301.4MHz Bandpass Filter Adjustment Waveform

16.On the synthesized sweeper, press IIv13) and set the Marker to the -3 dB point on the low side of the filter response.

17.On the synthesized sweeper, press (M4) and set the Marker to the -3 dB point on the high side of the filter response.

3-114 Adjustments

16. Second IF Amplifier and Third Converter Adjustment

Note Place the Markers as accurately as possible within the cursor markers for maximum frequency accuracy.

18.On the synthesized sweeper, press @G-X-n). M3 - M4 should read between 7 and 14 MHz.

19.On the synthesized sweeper, press [MKR] OFF and @iW] OFF.

20.Set the synthesized sweeper FREQUENCY MARKERS (M1) to 251.4 MHz and IIv12) to 351.4 MHz.

21.Set the Scalar Network Analyzer (ml to 10 dB and set IREF) (REF LEVEL) to + 14 dB. Set the REF POSN to one division down from the top.

22.Adjust A19C12 for minimum amplitude response at 258.4 MHz. Refer to Figure 3-64 for the location of the bandpass adjustments. Refer to Figure 3-66 for the typical response when the bandpass filter is properly adjusted.

2 8 0 MHz,

Figure 3-66. Minimum Image Response at 258.4 MHz

Note

Third Converter

Adjustment

23.Repeat the adjustments in steps 13 and 22 to assure that the bandpass is between 7 MHz and 14 MHz and the image response at 258.4 MHz is minimized.

Remember to use the appropriate set up for steps 13 and 20.

24.Disconnect the cables from A19Jl and A19J2 and reconnect the instrument cables.

25.Disconnect cable 83 (gray/orange) from A20J3 and connect A20J3 to the input of HP 8566A/B Spectrum Analyzer, using a BNC to SMB test cable.

26.Press ~NSTR PRESET) on the HP 8566A/B Spectrum Analyzer, then

key in [CENTER FREQUENCY) 280 MHz, [FREQUENCY SPAN) 2 MHz. Set

MARKER [j), (REFERENCE) + 2 dBm, and [ENTER dB/DIv)

1dB.

27.Adjust A20 AMPTD A20Ll for maximum signal level as indicated on spectrum analyzer display.

28.Disconnect spectrum analyzer and reconnect cable 83 (gray/orange) to A20J3.

Adjustments 3-115

16. Second IF Amplifier and Third Converter Adjustment

17. Pilot Second IF

Amplif???ier

Adjustments

Reference

RF Section:

A9 Pilot Second IF Amplifier

A10 Pilot Third Converter

Description A synthesized sweeper is used to inject a signal of 269 MHz at

-20 dBm into the A9 Pilot Second IF Amplifier. The output of the amplifier is displayed on a scaler network analyzer. The amplifier is adjusted for a bandpass of greater than 21 MHz centered at 269 MHz and a gain of greater than + 10 dB.

SYNTHESIZED !WEEPER

POAFR METER

NETWRK ANALYZER

Figure 3-67. Pilot Second IF Amplifier Adjustments Setup

Equipment Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A/B Scalar Network analyzer . . . . . . . . . . . . . . . . . . . . . . . HP 8757A

Power Splitter . . . . . . . . . . . . . . . . . . . . . . HP 11667A Opt. 001

Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A

Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP8482 A Detector (2 required) . . . . . . . . . . . . . . . . . . . . . . . . . HP 11664A 20 dB Attenuator . . . . . . . . . . . . . . . . . . . . HP 8491A, Opt. 020

Adapters:

Type N (f) to APC-3.5 (f) . . . . . . . . . . . . . . . . . . . . . .

Type N (m) to BNC (f) (2 required) . . . . . . . . . . . . .

Type N (f) to BNC (f) (2 required) . . . . . . . . . . . . . .

APC 3.5 (f) to APC 3.5 (f) . . . . . . . . . . . . . . . . . . . . .

1250-1745

1250-0780

1250-1474

1250-1749

Cables:

BNC to SMB Snap-On (Service Accessory) (2 required) . 85680-60093

BNC 122 cm (48 in) (3 required) . . . . . . . . . . . . . . . . . . 10503A SMA (m) to (m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5061-5458

3-116 Adjustments

17. Pilot Second IF Amplifier Adjustments

Procedure 1. Position instrument on right side as shown in Figure 3-67, with bottom cover removed.

2.Set LINE switch to ON and press GNST PRESET) on HP 8568B (DUT), HP 8757A, and HP 8340A/B.

3.Connect 20 dB Attenuator and power splitter to RF OUTPUT of synthesized sweeper. Connect one arm of power splitter to R input of scalar network analyzer through detector as shown in Figure 3-67.

4.Set synthesized sweeper FREQUENCY MARKERS IN11) to 254 MHz and lM2) to 284 MHz.

5.Press Icw) 269 MHz on synthesized sweeper.

6.Connect Power Meter to the other power splitter port and set synthesized sweeper POWER LEVEL) for a Power Meter indication of -20.0 ho.2 dBm.

7.Disconnect Power Meter and connect power splitter output to A9J1, using adapter and BNC to SMB test cable.

8.Connect A9J2 to A input of scalar network analyzer through detector, using adapter and another BNC to SMB test cable.

9.Connect synthesized sweeper SWEEP OUTPUT (rear panel), Z-AXIS BLANK/MKRS (rear panel), and PULSE MODULATION INPUT (front panel) to proper rear-panel connectors on scalar network analyzer, shown in Figure 3-67.

10.On scalar network analyzer, turn channel 2 off and press m (A/R).

11.Set the scalar network analyzer [SCALE_) to 1 dB, and set (REF) (REF LEVEL) to + 10.00 dB. Set REF POSN (press REF POSN) to the fourth division from the bottom using the data knob.

12.On synthesized sweeper, press (W] (ON), [MKR SWEEP), and InF). Set SWEEP TIME to 500 ms.

13.Adjust REF LEVEL for a mid-screen response of signal on HP 8757A.

14.Adjust A9 269 MHz Bandpass Filter, A9C9, A9Cl0, A9Cl1, and A9C12, for best bandpass filter response with gain of greater than + 10 dB (above REF 1 line). See Figure 3-68 for location of adjustments. Figure 3-69 shows typical response when the bandpass filter is properly adjusted.

Adjustments 3-l 17

17. Pilot Second IF Amplifier Adjustments

Figure 3-68.

Location of 269 MHz Bandpass Filter Adjustments

3 dB Point

> 2 1 MHz -4

Figure 3-69.

269 MHz Bandpass Filter Adjustments Waveforms

15.On the scalar network analyzer, press [CURSOR) MAX. Press cursor A, ON and set the cursor to the -3 dB point on the low side of the filter response (fO.1 dB).

16.Press cursor A and set the cursor to the -3 dB point on the high side on the filter response. The cursor A should read 0 kO.1 dB.

17.Press @ on synthesized sweeper and set to three divisions down (3 dB) from top of bandpass filter response. Press (M4) and set to three divisions down on opposite side of bandpass filter response.

18.Press MKR A on synthesized sweeper. M3-M4 should be greater than 21 MHz.

19.Disconnect cable 80 (greyblack) from A9Jl and cable 81 (greybrown) from A9J2 and reconnect instrument cables.

3-118 Adjustments

18. Frequency

Control

Adjustments

Reference

Related Performance

Tests

Description

18. Frequency Control Adjustments

RF Section:

A22 Frequency Control

Sweep Time Accuracy Test

Frequency Span Accuracy Test

Center Frequency Readout Accuracy Test

The sweep reference voltage is adjusted and then the sweep times are adjusted for proper tolerances. The sweep tune voltage is adjusted. Then the YTO DAC, VT0 DAC, and LSD VT0 DAC are adjusted, each to within its tolerance. Next, the Start and Stop frequencies are adjusted. FM Span is adjusted next for the proper amount of FM deviation.

SPECTRUM ANALYZER

Procedure 1. Place instrument on right side with IF-Display facing right as shown in Figure 3-70 and remove bottom cover.

2.Set LINE switch to ON and press QNSTR PRESET).

3.Connect DVM to A22TP15 and ground to A22TP12.

4.Adjust A22 REF A22R94 for DVM indication of + 10.00 ho.01 V dc.

See Figure 3-71 for location of adjustment.

Adjustments 3-l 19

18. Frequency Control Adjustments

A22

S T A R T

F M S P A N

Start-Up Time

Measnremtwt

Note

Slow Sweep

Adjustment

Note

F R E O U E N C Y C O N T R O L

S T O P

T I L T

Y T O

-SD VT0

TlJNE R E F

R E F

F A S T

A22

Figure 3-71. Location of Frequency Control Adjustments

5. Connect DVM to A22TP13 and ground to A22TP12.

6. Adjust A22 TUNE REF A22R17 for DVM indication of -10.285 AO.001 V dc. See Figure 3-71 for location of adjustment.

7. Key in [CENTER FREQUENCY) 10 MHz, CFREQUENCY SPAN] 0 Hz, Trace A [CLEAR-WRITE), Sweep @???i!i?Z], Scale LIN.

8. Key in Isv\IEEP TIME) Is, Marker I-1. Adjust marker to the left edge of the CRT. Key in (SHIFT) (ml ???, then key in (SHIFT) C-1 F three times. CRT annotation should indicate SWEEP GEN measured sweep time.

1 second start-up time:

The start-up time measured in step 8 uses the [sHIFTl[BW)r function that displays a sweep time value which is 1% to 5% longer than the actual spectrum analyzer sweeptime. This error is compensated when using the shift F function to adjust the sweep times in the following procedure.

9.Key in Marker loFF) then [ml.

10.Key in [SHIFT) (BW] F three times and note the CRT annotation. The annotation should indicate SWEEP GEN

measured sweep time of (1 .OO s + start-up time from step 8) +O.Ol s. To adjust sweep time, adjust A22R88 SLOW slightly, then key in (SHIFT) [REsBW) F and note new SWEEP GEN measured sweep time as indicated by CRT annotation. Repeat this process until the 1 s sweep time is within spec.

Adjusting A22R88 CW decreases the sweeptime.

3-120 Adjustments

Full Sweep

Adjustment

Note

YTO and VT0 DAC

Adjustments

18.Frequency Control Adjustments

11.Repeat Start-Up Time Measurement procedure in step 8 and step 9 for (SWEEP TIME) of 20 ms. Note value of measurement.

20 ms start-up time:

12.Key in [Shift_) CREssWr three times and note the CRT annotation. The annotation should indicate SWEEP GEN measured sweeptime of (20 ms + start-up time noted in step ll)*O.l ms. If it is not in spec, determine the difference between this measured sweep time and the target sweep time of 20 ms + start-up time noted in step 11.

(measured sweep time) - (20.00 ms + start-up time) =

13.Adjust A22R91 FAST for three times the difference; and in the opposite direction, as noted in step 12. See note below. Adjust A22R91 slightly then key in [SHIFT) [REsy and note new SWEEP GEN measured sweep time as indicated by CRT

annotation. Repeat this process until the 20 ms sweep time is set to the value calculated in this step.

Adjusting A22R91 CW increases the sweeptime. If the difference between the measured 20 ms sweep time and the target sweep time is less than approximately 0.3 ms, adjust A22R91 for the target sweeptime. Adjusting A22R91 to 3 times the difference noted in step 12 is only needed if the difference noted in step 12 is greater than 0.3 ms.

14.Repeat the adjustments in step 8 through step 13 until the measured sweep time at 20 ms is 20 ms plus the Start-Up Time measured in step 11 (fO.1 ms) and the measured sweep time at 1 s is 1.00 s plus the start-up time measured in step 8 (50.01 s).

15.Key in Cm) [CF STEP SIZE) J 0 MHz. The CRT annotation should indicate DACS 0.

16.Connect DVM to A22TP6 and ground to A22TP12. If using an HP 3456ADVM,press(STOREI(?JZ,(ENTEREXP)y,@,cm)(81

???, then INIATH_), (?J (X-~/Y. If not using an HP 3456A DVM, note voltage indication for reference later.

17.Key in (ml [CF STEP SIZE) J 1023 MHz. (CRT annotation may still indicate DACS 1023.)

18.Adjust A22 YTO A22R25 for DVM indication of + 10.230 kO.001 V dc. If not using an HP 3456A DVM, adjust for specified voltage plus the DVM indication noted in step 16. See Figure 3-71 for location of adjustment.

19.On the HP 3456A, Press INIATH_) @ OFF.

20.Connect DVM to A22TP9.

21.Key in [SHIFT) [CF STEP SIZE) J 0 Hz. If using an HP 3456A DVM, pressISTORE_)@Z,~@Y,@,(STORE)@Y, then (MATH_), 0 (x-z),y. If not using an HP 3456A DVM, note voltage indication for reference later.

Adjustments 3-121

18.Frequency Control Adjustments

22.Key in (ml [CF STEP SIZE) J 1023 Hz.

23.Adjust A22 LSD VT0 A22R7 for DVM indication of +0.0218 f0.0001 V dc. If not using an HP 3455A DVM, adjust for specified voltage plus the DVM indication in step 20. See Figure 3-71 for location of adjustment.

24.On the HP 3456A, press INIATH) (ZJ err.

START and STOP

Adjustments

25.Connect frequency counter to rear-panel 1ST LO OUTPUT connector.

26.Press (~NSTR PRESET), then key in ISHIFT) CCF STEP SIZE) J. CRT annotation should indicate DACS 0.

27.Adjust A22 START A22R39 for frequency counter indication of 2.050 GHz f 0.002 GHz. See Figure 3-71 for location of adjustment.

28.Key in ISHIFT) CCF STEP SIZE) J 1023 MHz. CRT annotation should indicate DACS 1023.

29.Adjust A22 STOP A22 STOP A22R35 for frequency counter indication of 3.7891 *0.002 GHz. See Figure 3-71 for location of adjustment.

FM SPAN Adjustment 30. Press (INSTR PRESET), then key in (CENTER FREQUENCY) 10 MHz,

[FREQUENCY SPAN] 20 MHZ.

31.Connect CAL OUTPUT to SIGNAL INPUT 2.

32.Adjust A22 FM SPAN A22R64 so that the LO Feedthrough signal is centered on the left edge graticule and the 20 MHz CAL OUTPUT signal is centered on the right edge graticule. See Figure 3-71 for location of adjustment.

3-122 Adjustments

19. Second Converter Adjustments

19. Second

Converter

Adjustments

Reference

Related Performance

T e s t

Description

RF Section:

A23 RF Converter

RF Gain Uncertainty Test

Spurious Responses Test

First, the second LO frequency is adjusted for proper frequency and then the LO shift is adjusted by using the front-panel keys to shift the LO up and down. Next, the Pilot IF Bandpass Filter is adjusted for proper bandpass and amplitude, then the signal IF Bandpass Filter

is adjusted. The second LO frequency and shift are checked and readjusted, if necessary.

SYNTHESIZED WEEPER

R POWER METER

PDWER

SENSOR

2 0 dB

ATTENUATOR

Figure 3-72. Second Converter Adjustments Setup

Equipment Frequency Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 5340A Scalar Network Analyzer . . . . . . . . . . . . . . . . . . . . . . . HP 8757A

Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A/B

Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8447F

Power Splitter . . . . . . . . . . . . . . . . . . . . . . HP 11667A Opt. 001

Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A

Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP8482 A Detector (2 required) . . . . . . . . . . . . . . . . . . . . . . . . HP 11664A

Adjustments 3-123

19. Second Converter Adjustments

Procedure 1. Remove A23 RF Converter assembly from HP 8568B Spectrum Analyzer. Removal and installation procedures are contained as a repair procedure in the RF Section of the Troubleshooting and Repair Manual, Volume 1.

2.Position instrument on right side as shown in Figure 3-72 with the RF Converter removed but with cables still connected.

Second LO Frequency

and Shift Adjustments

Note

3. Set HP 8568B Spectrum Analyzer LINE to ON and press

(JNSTR PRESET].

The second LO and pilot second LO output power is typically -35 dBm or less. An HP 8447F amplifier is used in steps 1 through 26 to amplify the LO power to a useable level for the counter and power meter.

Note The following adjustment tools are required to adjust the

second converter: allen driver (08555-20121) and hex nut driver (08555-20122). Place the allen driver through the center hole of the hex nut driver. Loosen the adjustment nut using the hex nut driver while adjusting the bandpass with the allen driver. Do not over tighten the nut on the second converter.

4.Connect the amplifier???s input to A23A3J3 and the power meter to the amplifier???s output.

5.Adjust A23A3 2ND MIXER A23A3Z4 for maximum power meter indication. See Figure 3-73 for location of adjustment.

z4,N,??????LD ???Zl Z2 Z3 L2??? 2HD Ml XER FREO

A23A3

Figure 3-73. Location of Second Converter Adjustments

6.Disconnect power meter and connect frequency counter to amplifier???s output.

7.Adjust A23A3 2ND LO FREQ A23A3Z9 for frequency counter indication of 1748.6 MHz fl.O MHz. See Figure 3-73 for location of adjustment.

8.Disconnect frequency counter and reconnect power meter to amplifier???s output.

3-l 24 Adjustments

19.Second Converter Adjustments

9.Readjust A23A3 2ND MIXER A23A3Z4 for maximum power indication.

10.Disconnect the amplifier???s input from A23A3J3 and connect to A23A3J4.

11.Adjust A23A3 PILOT 2ND MIXER A23A3Z8 for maximum power meter indication. See Figure 3-73 for location of adjustment.

12.Disconnect power meter and connect frequency counter to amplifier???s output.

13.Key in [SHIFT) @) u to shift Second LO up and ISHIFT) a T to shift Second LO down.

14.Continue to shift Second LO up and down while adjusting A23A3 2ND LO SHIFT A23A3ZlO for a frequency difference of 5.0 MHz fO.l MHz. Ignore the absolute value of either frequency. Clockwise rotation of A23A3ZlO decreases the frequency difference.

15.Key in (SHIFT) a T (Second LO shifted down).

16.Adjust A23A3 2ND LO FREQ A23A3Z9 for frequency counter indication of 1748.6 MHz fO.l MHz.

17.Repeat steps 13 through 16 until specifications of steps 14 and 16 are achieved.

18.Disconnect frequency counter and connect power meter to the amplifier???s output.

19.Shift Second LO up and down, using m m u and (SHIFT) a

T while adjusting A23A3 PILOT 2ND MIXER A23A3Z8 for equal power out in both states of Second LO.

20.Power difference between Second LO shifted up and shifted down should be less than 0.5 dB.

21.Disconnect amplifier???s input from A23A3J4 and connect to A23A3J3.

22.Shift Second LO up and down, using (SHIFTY a u and ISHIFT) @) T while adjusting A23A3 2ND MIXER A23A3Z4 for equal power out in both states of the Second LO.

23.Power differences between Second LO shifted up and shifted down should be less than 0.5 dB.

24.Disconnect power meter and connect frequency counter to amplifier???s output.

25.Key in [SHIFT) a T. Note frequency counter indication. If necessary, readjust A23A3 2ND LO FREQ A23A3Z9 for frequency counter indication of 1748.6 fO.l MHz.

26.Shift Second LO up and down, using ISHIFT) @) ??? and ISHIFT) a

T and note frequency difference between low and high state of Second LO. If necessary, readjust A23A3 2ND LO SHIFT A23A3ZlO for a frequency difference of 5.0 MHz fO.l. Repeat steps 27 and 28 until specifications contained in each step are achieved.

Adjustments 3-125

19. Second Converter Adjustments

Second Converter

Bandpass Filter

Adjustments

Note

27.Key in m (JJ) T, [FREQUENCY SPAN] 0 Hz.

28.On the synthesized sweeper, key in ICF) 240 MHz, a 50 MHz, and CPowerLeVel] - 10 dBm.

29.Connect the synthesized sweeper???s SWEEP OUTPUT (rear panel), Z-AXIS BLANK/MKRS (rear panel), and PULSE MODULATION INPUT (front panel) to the proper rear-panel connectors on the scalar network analyzer as shown in Figure 3-73.

30.On the scalar network analyzer, press PRESET, turn channel 2 off, and press [MEAS] (A/R).

31.Connect the synthesized sweeper???s output to the power splitter as shown in Figure 3-72.

32.Connect one arm of power splitter to scalar network analyzer R input. Connect other arm of power splitter to A input, using a BNC to SMB snap-on test cable and necessary adapters.

33.Set the scalar network analyzer c-1 to 1 dB, and set m (REF LEVEL) to -16.00 dB. Set REF POSN (press REF POSN) to the

fourth division from the bottom using the data knob.

34. On the synthesized sweeper, press [m) (ON), [MKR SWEEP), and @FJ. Set @WEEP TIME] to 500 ms.

35.Adjust REF LEVEL for a mid-screen response of the bandpass signal on the scalar network analyzer.

36.Connect the test cable from the power splitter output arm to A23A3J2 Pilot First IF IN.

37.Connect cable 80 (gray/black) from A23A3J6 (PILOT 2ND IF) to the scalar network analyzer???s A input. Set Cm] to 10 dB/DIV.

38.On the spectrum analyzer, key in [SHIFT] (FREERUN)V.

Hold (SHIFT] in until the LED lights, then press I-) until the sweep is free running.

39.On the synthesized sweeper, set (CF) for a frequency of 2017.6 MHz and InF] to 50 MHz.

40.Adjust a on the synthesized sweeper to center the bandpass signal.

41.Adjust A23A3 25, Z6, 27, and L4 for best bandpass shape and flatness at maximum amplitude of signal displayed on Scalar network analyzer. A typical properly-adjusted bandpass filter response is shown in Figure 3-74. See Figure 3-73 for location

of adjustments. The bandpass filter response at the 3 dB points should be 222 MHz. See Figure 3-74 and Figure 3-75 for a typical PILOT 2ND IF bandpass response for a SHIFT LO 1 and a SHIFT LO 1.

3-126 Adjustments

19. Second Converter Adjustments

Figure 3-74. Typical PILOT 2ND IF Bandpass (SHIFT t)

Figure 3-75. Typical PILOT 2ND IF Bandpass (SHIFT 1)

42.Key in [*] 0) u and note amplitude of signal. Key in ISHIFT) @a T and note amplitude of the bandpass signal peak.

43.Continue to key in [SHIFT] 0) u then a T while adjusting

A23A3Z8 for maximum amplitude and the same amplitude in both states of the Second LO ??? tcO.25 dB.

44.Check the bandpass at the 3 dB points for both the 2ND LO 1

and 1. On the scalar network analyzer, press (CURSORJ Max. Press cursor A (ON) and set the cursor at the -3 dB point fO.l dB. Press cursor A, cursor A, and set the cursor to the corresponding -3 dB point on the opposit side of the signal. The cursor should now read 0 fO.l dB.

45.On the synthesized sweeper, press Irvr3) and place the marker on either cursor A. Press (M4), and place the marker on the cursor A on the opposite side of the trace.

46.On the synthesized sweeper, press [Morn), and read the bandpass (M3 - M4) shown on the ENTRY DISPLAY. Press [Morn) OFF. See Figure 3-74 and Figure 3-75.

47.Disconnect the detector from cable 80 (gray/black) and connect cable 92 (white/red) from A23A3J5 (2ND IF) to the scalar network analyzer???s A input.

Adjustments 3-127

19.Second Converter Adjustments

48.Disconnect cable connected to A23A3J2 and connect to A23A3Jl (1ST IF IN). Reconnect semi-rigid cable to A23A3J2 that was disconnected in step 36.

49.Set the synthesized sweeper???s a for 2052.5 MHz ho.1 MHz. Adjust a to center the bandpass signal.

50.Adjust A23A3 Zl, 22, 23, and L2 for best bandpass shape and flatness at maximum amplitude of signal displayed on Scalar network analyzer. A typical properly-adjusted bandpass filter response is shown in Figure 3-76 and Figure 3-77. See Figure 3-73 for location of adjustments. The bandpass response should be 222 MHz.

1i i i i ii i I

Figure 3-76. Typical Bandpass (SHIFT T)

Figure 3-77. Typical Bandpass (SHIFT 1)

51.Keyin=@) u and note amplitude of the bandpass signal peak. Key in (SHIFT) a T and note amplitude of the bandpass signal peak.

52.Continue to key in ISHIFT) @j u then m a T while adjusting A23A3Z4 for maximum amplitude and the same amplitude in both states of the Second LO fcO.1 dB.

3-128 Adjustments

Second Converter

Final Adjustments

19.Second Converter Adjustments

53.Repeat steps 14 through 19 to ensure that Second LO frequency and shift are still properly adjusted.

54.Check the bandpass at the 3 dB points for both the 2ND LO T

and 1. On the scalar network analyzer, press [%i?%@ Max. Press cursor A a and set the cursor at the -3 dB point 50.1 dB. Press cursor A, cursor A, and set the cursor to the corresponding -3 dB point on the opposite side of the signal. The cursor should now read 0 kO.1 dB.

55.On the synthesized sweeper, press Ihns) and place the marker on either cursor A. Press (M4), and place the marker on the cursor A on the opposite side of the trace.

56.On the synthesized sweeper, press [MKRn), and read the bandpass (M3 - M4) shown on the ENTRY DISPLAY. Press C-1 OFF. See Figure 3-74 and Figure 3-75.

57.Disconnect all test equipment from HP 8568B Spectrum Analyzer and reconnect all cables within the instrument: cable 80 (gray/black) between A23A3J6 and A9J1, and cable 92 (white/red) between A23A3J5 and A19Jl.

58.Connect HP 8568B Spectrum Analyzer CAL OUTPUT to SIGNAL INPUT 2. Key in (CENTER FREQUENCY) 20 MHz, (FREQUENCY SPAN) 1

MHz, (REFERENCE LEVEL] -7 dBm, SCALE LOG [ENTER dB/DIv) 1 dB, (REs) 300 kHz.

59.Key in @iFi] @j u , (PEAK SEARCH] Key in m @ T and note signal amplitude as indicated by marker level CRT annotation.

60.Continue to key in ISHIFT) @) u then (SHIFT) (IJ T while adjusting A23A3Z4 for maximum amplitude and the same amplitude in both states of the Second LO 3x0.1 dB.

61.Reinstall RF Converter in instrument. See installation procedure in RF Section of Troubleshooting and Repair Manual, Volume 1.

Adjustments 3-129

20. 50 MHz

Voltage-Tuned

Oscillator

Adjustments

Reference

Related Performance

Test

Description

RF Section:

All 50 MHz Voltage-Tuned Oscillator (VTO)

Frequency Span Accuracy Test

Center Frequency Readout Accuracy Test

First, the voltage reference for the Shaping network is set by measuring the voltage required to tune the 50 MHz Oscillator to its high limit (57.5 MHz) and then setting the reference voltage (+ 15 VR) to that voltage.

Next, the VT0 tuning accuracy is adjusted at both the low and high end by setting the tune voltage to the proper levels to tune the VT0 to its low and high end limits (42.5 MHz and 57.5 MHz). This is done using the output of the tuning DACS from the A22 Frequency Control; therefore, it is necessary that the DAC adjustments on the Frequency Control have been performed before adjusting the 50 MHz VTO.

SPECTRUM ANALYZER

DIGITAL VOLTMETER

peJy$jjqy

Equipment

Procedure

Figure 3-78. 50 MHz Voltage-Tuned Oscillator Adjustments Setup

Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

1.Position Instrument on right side as shown in Figure 3-78 and remove bottom cover. Remove All 50 MHz Voltage-Tuned Oscillator and place on extenders.

2.Set LINE switch to ON and press [INSTR PRESET).

3-130 Adjustments

DACS Accuracy Check

Positive Supply

Adjustment

20.50 MHz Voltage-Tuned Oscillator Adjustments

3.Connect DVM to A22TP9 and ground lead to A22TP12.

4.Key in [SHIFT) [CF STEP SIZE] J 0 Hz. If using an HP3456A DVM, pressISTORE_)aZ, way, a, (STORE)@JY, then

@El 0 (X-Z)/Y. If not using an HP 3456A DVM, note voltage indication for reference later.

5.Key in [m] [CF STEP SIZE) J 1023 kHz.

6.If using an HP 3456A DVM, voltage indication should typically be be + 10.230 fO.O1O V de. If not using an HP 3456A DVM, voltage indication should be + 10.230 fO.O1O V de plus the indication noted in step 4. If voltage is within tolerance, proceed to next step. If voltage indication is incorrect, go to Adjustments 18, Frequency Control Adjustments, and perform YTO and VT0 DAC adjustments.

7.On the HP 3456A, press MATH off.

8.Key in &ENTER FREQUENCY) 1 MHz, [FREQUENCY SPAN) 1 MHz.

Connect DVM to AllTP5 and ground lead to Al 1 cover.

9.Key in ISHIFT) ~CF STEP SIZE) J 12 kHz. (CRT annotation should indicate DACS 12.)

10.Key in (SHIFT) (MKRW1 N. (CRT annotation should indicate VT0 frequency of approximately 28.75 MHz. This corresponds to a VT0 frequency of 57.5 MHz, since the counter indication is

divided by two.)

11.Adjust All OFFSET AllRlO and/or All GAIN AllR9 for VT0 frequency of 28.750 MHz f0.005 MHz as indicated by CRT annotation. See Figure 3-79 for location of adjustment.

A l 1

50MHr VOLT! 1GE-TI J N E D O S C I L L A T O R

J

Figure 3-79. Location of 50 MHz VT0 Adjustments

12.Note DVM indication for reference later.

13.Connect DVM to AllTPl (located on All cover).

Adjustments 3-131

20.50 MHz Voltage-Tuned Oscillator Adjustments

14.Adjust All POS SUPPLY AllR6 for a DVM indication the same as that noted in step 12. See Figure 3-79 for location of adjustment.

VT0 High-Frequency

End Adjustment

15.Key in LSHIFT) (CF STEP SIZE] J 112 kHz and Cm) I-1 N.

16.Adjust All OFFSET AllRlO for VTP frequency indication 28.000 MHz f0.005 MHz.

17.Key in ISHIFT) [CF STEP SIZE) J 12 kHz and [SHIFT) I-1 N.

18.Adjust All GAIN AllR9 for VT0 frequency indication of 28.750 MHz fO.005 MHz.

VT0 Low-Frequency

End Adjustment

19.Repeat steps 15 through 18 until specifications of steps 16 and 18 are achieved.

20.Key in ISHIFT) [CF STEP SIZE] J 912 kHz (m) [wCF_) N.

21.Adjust All SHAPING ATTN AllR42 for VT0 indication of 22.000 MHz f0.005 MHz. See Figure 3-78 for location of adjustment.

22.Key in (Ml (CF STEP SIZE) J 1012 kHz and [SH???FT) [NII(R) N.

VT0

Center-Frequency

Checks

23.Adjust All SHAPING OFFSET AllR17 for VT0 frequency indication of 21.250 MHz *0.005 MHz. See Figure 3-78 for location of adjustment.

24.Repeat steps 21 through 23 until specifications of steps 20 and 23 are achieved.

25.Go back to step 15 and repeat both High-Frequency End and Lo-Frequency End adjustments until specifications of both (contained in steps 16, 18, 21, and 23 are achieved.

26.Key in ($KEj [CF STEP SIZE) J 512 kHz and Cm) [m) N.

27.VT0 frequency indication should be 25.00 MHz f0.02 MHz. If it is not, and specifications of steps 16, 18, 21, and 23 are met, a malfunction is indicated. The most likely suspects would be varactor diodes CR15 and CR16.

28.Key in ISHIFT_) [CF STEP SIZE] J 612 kHz and cm] I-1 N.

29.VT0 frequency indication should be 24.25 MHz kO.02 MHz. If it is not, and specifications of steps 16, 18, 21, and 23 are met, a malfunction is indicated. The most likely suspects would be varactor diodes CR15 and CR16.

30.Set LINE switch to STANDBY.

31.Replace Al1 50 MHz Voltage-Tuned Oscillator in instrument without extenders and replace screws in cover.

3-132 Adjustments

21. Slope

Compensation

Adjustments

Reference

Related Performance

Test

Description

2 1. Slope Compensation Adjustments

RF Section:

A22 Frequency Control

Frequency Response Test

The HP 8568B Spectrum Analyzer is swept between 10 MHz and 1500 MHz, using a synthesized sweeper which has been power-meter leveled. The resulting response curve is displayed on the HP 8568B Spectrum Analyzer CRT and the slope compensation (TILT) adjustment is performed to compensate for the frequency response roll-off of the first mixer.

SYNTHESIZED WEEPER

PDWER METER

PCMR

SENSORADAPTER

-wkd-

PMR SPLITTER

Figure 3-80. Slope Compensation Adjustment Setup

Equipment Synthesized Sweeper . . . . . . . . . . . . . . . . . . . . . . . . HP 8340A/B Power Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP436 A Power Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..HP8482 A Power Splitter . . . . . . . . . . . . . . . . . . . . . . HP 11667A Opt. 001

Adapters:

Type N (m) to N (m) . . . . . . . . . . . . . . . . . . . . . . . . . . 1250-0778

Type N (m) to APC 3.5 (f) . . . . . . . . . . . . . . . . . . . . . 1250-1744

APC 3.5 (f) to APC 3.5 (f) . . . . . . . . . . . . . . . . . . . . . 1250-1749

Cables:

SMA (m) (m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5061-5458

Adjustments 3-133

2 1. Slope Compensation Adjustments

Procedure 1. Place instrument on right side as show in Figure 3-80, and remove bottom cover.

2.Connect equipment as shown in Figure 3-80 with power splitter connected to the output of the synthesized sweeper with a cable. Connect one arm of the splitter directly to the SIGNAL INPUT of the HP 8568B Spectrum Analyzer, using a Male-to-Male adapter, and the other arm to the power sensor.

3.Connect the power meter???s recorder output to the HP 8340A/B???s

LEVELING EXT INPUT.

4.Press (INSTR PRESET] on the synthesized sweeper, and set its controls to the following settings:

CW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100MHz

POWER LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . -9.0 dBm

RF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..on

LEVELING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INT

5.On the synthesized sweeper, press (POWER LEVEL] and adjust the ENTRY knob as necessary for a power meter indication of -15.00 dBm *2.00 dB at 100 MHz.

6.On the power meter, press [RANGE HOLD] (turning it on).

7.On the synthesized sweeper, press [POWER LEVEL] and adjust the ENTRY knob for a power meter indication of -10.00 dBm kO.03 dB at 100 MHz.

8.On the synthesized sweeper, press cm] LEVELING and adjust the ENTRY knob (REF in dBV with ATN: 0 dB) for a power meter indication of -10.00 dBm f0.03 dB at 100 MHz.

Note Do not vary the synthesized sweeper POWER LEVEL setting (internal leveling) or METER REF and METER ATN settings (external power meter leveling) for the remaining steps in this section of the adjustment procedure. The frequency response adjustments are referenced to the -10.00 dBm power level at 100 MHz.

9. Set the synthesized sweeper to the following settings:

START . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10MHz

STOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1500 MHz

SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40s

SWEEP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SINGLE

10.Set HP 8568B LINE switch to ON and press (INSTR PRESET].

11.Key in (START FREQ) 10 MHz, [sTopI 1500 MHz,

(REFERENCE LEVEL) -10 dBm, LOG CENTER dB/Div] 1 dB.

12.On the spectrum analyzer, press TRACE A, (CLEAR WRITE), and (NlAXHOLD).

13.Trigger two full sweeps on the synthesized sweeper.

3-134 Adjustments

21. Slope Compensation Adjustments

Note At this sweep time, some trace discontinuities are common.

14.Adjust A22R66 TILT for best flatness (clockwise rotation increases the power slope), and trigger two sweeps on the synthesized sweeper. See Figure 3-81 for the location of A22R66. Compare the resultant trace with the specification. Continue adjusting A22R66 until best flatness is achieved.

Note Best flatness is achieved when the maximum number of frequency points are on or near the -14 dBm reference.

A22

F R E O U E N C Y C O N T R O L

I/I IAII

R66 T I L T

Figure 3-81. Location of A22R66 TIIIT Adjustment

15.Press TRACE A, m, [PEAK SEARCH], and [MARKER DELTA). Using the data knob, place the marker on the lowest power peak. The marker???s absolute value should be less than 2 dB.

16.See Figure 3-82 for examples of typical displays of frequency response correctly and incorrectly adjusted.

FREQUENCY RE

MALAD.JUS TED

Figure 3-82. Slope Compensation Adjustment Waveforms

Adjustments 3-135

22. Comb

Generator

Adjustments

Reference

RF Section:

A23 RF Converter

Al6 20 MHz Reference

Description The output of the Pilot First Converter is connected to the signal input of the Second Converter. This allows the comb teeth from the A23A6 Comb Generator to be displayed on the CRT display. The

phase lock flags are disabled, using a shift key function to prevent the instrument from ???locking up??? due to the phase lock loops being open. A display line is placed on the CRT at the level to which the comb teeth are to be adjusted. the comb teeth are adjusted for best overall flatness and to the proper amplitude.

R31 C O M B D R I V E

A23A6

COMB (;ENt IRATOR

\IIi

A6C7 H F P E A K (Benenth C o v e r )

A612 COMB PEAK / A4A2RE C O M B B I A S

Figure 3-83. Location of Comb Generator Adjustments

3-136 Adjustments

22. Comb Generator Adjustments

Equipment Cable, SMA (m) to SMA (m) . . . . . . . . . . . . . . . HP 85680-20094

Procedure 1. Set instrument LINE switch to ON and press ~NSTR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Key in CCENTER FREQUENCY) 20 MHz, [FREQUENCY SPAN] 100 kHz,

(ATTEN) 0 dB, LOG [ENTER dB/DIvj 2 dB.

4.Adjust front-panel AMPTD CAL for signal peak at top graticule line (-10 dBm).

5.Press QNSTR PRESET).

6.Key in [SHIFT) [RUN) ???. This disables phase lock flags.

7.Position instrument on right side and remove bottom cover.

8.Disconnect cables from A23A5J2 (PILOT IF OUT) and A23A3Jl (1ST IF IN) and connect a short, low-loss coaxial cable with SMA male connectors ( do not use adapters) between A23A5J2 and A23A3Jl. Use coaxial cable, HP Part Number 85680-20094. If not available, remove A23FL2 FILTER and use between A23A5J2 and A23A3Jl to adjust comb generator.

9.Key in (START FREQ] 40 MHz. Wait for CRT annotation at lower left of CRT display to indicate START 40 MHz.

10.Key in (mFRE9) 1560 MHz. Wait for CRT annotation at lower right of CRT display to indicate STOP 1560 MHz.

11.Key in [REFERENCE LEVEL] -20 dBm, (ATTEN] 0 dB, LOG (ENTER dB/DIv) 2 dB, DISPLAY LINE (ENTER] -30 dBm.

12.Adjust Al6 COMB DRIVE A16R31 for peak amplitude of CRT trace until comb teeth begin to ???wiggle.??? Then adjust COMB DRIVE A16R31 slightly counterclockwise until the lowest comb tooth (near START frequency) just begins to fall. See Figure 3-84 for a typical comb tooth display. See Figure 3-83 for location of adjustments.

U P P E R L I M I T -22 dBm

D I S P L A Y L I N E

A T - 3 0 dBm

L O W E R L I M I T

- 3 6 dBm

Figure 3-84. Comb Teeth Display

13.Adjust COMB BIAS A23A4A2R6 for peak amplitude of CRT trace until comb teeth begin to ???wiggle. ??? Then adjust COMB BIAS A23A4A2R6 slightly counterclockwise until the lowest comb tooth (near START) frequency) just begins to fall. See Figure 3-84 for

Adjustments 3-137

22. Comb Generator Adjustments

a typical comb tooth display. See Figure 3-83 for location of adjustments.

14.The majority of the comb teeth should be above the -30 dBm Display Line. No comb teeth should exceed -22 dBm, and no comb teeth should be less than -36 dBm.

15.If unable to adjust comb teeth as described in previous steps, proceed with the next step. If comb teeth are adjusted properly, do not perform the adjustments in the following steps. Skip to step 21.

16.Adjust A23A6 COMB PEAK A23A6L2 for maximum amplitude of comb teeth. See Figure 3-83 for location of adjustment.

17.If the highest-frequency comb tooth is too low (c-36 dBm), remove screws from cover of A23A6 Comb Generator and lift cover from housing, being careful not to break wire connections to internal circuit. It will be necessary to hold cover away from housing while performing the following adjustment.

18.Adjust A23A6 HF PEAK A23A6C7 for maximum amplitude of the highest-frequency comb tooth displayed ( comb tooth to far right of CRT). See Figure 3-84 for location of adjustment.

19.Replace cover on A23A6 and install screws.

20.Go back to step 12 and proceed with adjustments.

21.Remove cable from between A23A65J2 and A23A3J 1 and reconnect instrument cables to connectors from which they were removed.

3-138 Adjustments

23. Analog-To-Digital Converter Adjustments

23. Analog-To-Digital Converter Adjustments

Reference

Description

A3A8 Analog-to-Digital Converter

The Analog-to-Digital Ramp Converter is adjusted at zero and

full-scale by injecting a 0 V dc input and + 10 V dc input and adjusting the OFFS and GAIN controls until the ramp output at A3A8TPll toggles high to low. This sets the horizontal end points for the CRT trace display; when the sweep ramp input is at 0 V dc (the left graticule edge), trace position 1 is set, and when the sweep ramp

input is at + 10 V de (the right graticule edge), trace position 1000 is set.

This procedure requires a + 10 V dc source which is stable and noise-free. A simple supply circuit which can be built with common components is illustrated in Figure 3-93. If these components are unavailable, the alternate procedure provided below (using only the digital voltmeter) can then be used.

HP 54501A

OlGlTlZlNG

OSCILLOSCOPE

DIGITAL VOLTKTER

Figure 3-85. Analog-To-Digital Converter Adjustments Setup

Equipment Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501 Digital Voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A Low-Noise DC Supply (Optional) . . . . . . . . . . . . . . . . . . . . . See Figure 3-93

Adjustments 3-139

23. Analog-To-Digital Converter Adjustments

Procedure

Standard Procedure

1.Position instrument upright as shown in Figure 3-85 and remove top cover.

2.Set LINE switch to ON and press ~NSTR PRESET).

3.Procedure using Low-Noise DC Supply is illustrated in Figure 3-93.

a.Key in [BLANK) TRACE A and SWEEP [S???NGLE].

b.Disconnect cable 0 (black) from sweep ramp input A3A8Jl.

c.Short A3A8TP4 to A3A8TP5 or connect SMB snap-on short to A3A8J 1.

d.Connect the oscilloscope???s 1O:l probe to A3A8TPll and ground the probe???s ground to the A3 section???s card cage.

e.Set the oscilloscope settings as follows:

amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 0.1 V/div time scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..5.0~s coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..dc

f.Adjust A3A8R6 OFFS for a square wave displayed on the oscilloscope. The square wave should be approximately 4 Vp-p. See Figure 3-86 for location of adjustment.

A3A8

A N A L O G - T O - D I G I T A L C O N V E R T E R ( B e n e a t h C o v e r )

Figure 3-86.

Location of Analog-To-Digital Converter Adjustments

g.Remove short from A3A8TP4 and A3A8TP5 or disconnect the SMB snap-on short from A3A8Jl.

h.Press (INSTR PRESET).

i.Press MARKER c-1, 1498 (MHz), and CSHIFT) (SINGLE) ???.

j.Connect DVM to A3A8TP5 and ground to A3A8TP4. Set DVM for V de.

k.Connect output of the Low-Noise DC Supply to A3A8Jl. Adjust the Low-Noise DC Supply for DVM indication of + 10.000 &.OOlV dc.

3.140 Adjustments

23. Analog-To-Digital Converter Adjustments

1. Adjust A3A8R5 GAIN for a square wave displayed on the oscilloscope. The square wave should be approximately 4 V,,. See Figure 3-86 for location of adjustment.

Alternate Procedure 4. Procedure without using Low-Noise DC Supply:

a.Press QNSTR PRESET].

b.Key in TRACE A [BLANK] and SWEEP (SINGLE).

c.Disconnect cable 0 (black) from sweep ramp input A3A8Jl.

d.Short A3A8TP4 to A3A8TP5 or connect SMB snap-on short to A3A8Jl.

e.Connect DVM to A3A8TPll and ground to A3A8TP4. Set DVM for V ac.

f.Adjust A3A8R6 OFFS until the level at A3A8TPll is at a maximum ac voltage as indicated by the DVM (approximately 2.0 V ac). See Figure 3-86 for location of adjustment.

g.Remove short from A3A8TP4 and A3A8TP5. Reconnect cable 0 (black) to A3A8J 1.

h.Press ~NSTR PRESET].

i.Connect DVM to A3A8TP5 and ground to A3A8TP4. Set DVM for V dc.

j.Press SWEEP C-1. Note DVM reading at end of the sweep. The voltage will begin to drift immediately after the sweep ends. Therefore, the first indication after the sweep ends is the valid indication. It may be helpful to press [SINGLE) several times to ensure a valid indication at the end of the sweep.

k.If DVM indication is + 10.020 f0.005 V dc at the end of the sweep, no further adjustment is necessary. Otherwise, adjust A3A8R5 GAIN and repeat step j until the voltage at the end of the sweep is + 10.020 fO.005 V dc.

Adjustments 3-141

24. Track and Hold

Adjustments

Reference

Description

A3A9 Track and Hold

The CAL OUTPUT signal is connected to the RF INPUT. The instrument is placed in zero frequency span to produce a dc level output from the IF-Video section and this dc level is regulated by adjusting the reference level. The Offsets and Gains on the Track and Hold assembly are adjusted for proper levels using a DVM.

SPECTRUM

ANALYZER

DIGITAL VDLTMETER

2.Set LINE switch to ON and press (INSTR PRESET].

3.Connect CAL OUTPUT to RF INPUT.

4.Connect DVM to A3A9TP3 and ground to A3A9TPl.

5.Key in CCENTER FREQUENCY) 20 MHz, ~FREQUENCY SPAN] 0 Hz.

6.Disconnect cable 7 (violet) from A4AlJl.

7.Short A3A9TPl to A3A9TP3, or use an SMB snap-on short to A3A9Jl. DVM indication should be 0.000 IfrO.001 V de.

8.Key in CRINGLE], TRACE A (CLEAR-WRITE], MARKER C-1, MARKER [nl, SWEEP (CONT), (SHIFT_) TRACE A (BLANK) e.

9.Adjust A3A9R59 (T/H) OFS until MARKER A level indication as indicated by CRT annotation flickers back and forth between .OO and .lO dB. See Figure 3-88 for location of adjustment.

3-142 Adjustments

24. Track and Hold Adjustments

A6

AS ~EOM4LR ES A6A9AlRll

C A L A D J

II

A6A9Al

Figure 3-88. Location of Track and Hold Adjustments

10.Key in m TRACE A [-HOLD]. b

11.Adjust A3A9R44 OFFS POS until MARKER A level indication as indicated by CRT annotation flickers back and forth between .OO and .lO dB.

12.Key in cm) TRACE A m d.

13.Adjust A3A9R36 OFS NEG until MARKER A level indication as indicated by CRT annotation flickers back and forth between .OO and . 10 dB.

14.Key in ISHIFT) TRACE A [m) e.

15.Remove short from between A3A9TPl and A3A9TP3 or remove the SMB short from A3A9Jl. Reconnect cable 7 (violet) to A4AlJl.

16.Connect the DVM to A4AlTP3. Connect DVM???s ground to the IF section???s casting.

17.Press [REFERENCE LEVEL] and adjust DATA knob and front-panel AMPTD CAL adjust for a DVM indication of +2.000 fO.OO1 V dc at A4AlTP3.

18.Disconnect DVM from instrument.

19.Key in Cm), TRACE A (CLEAR-WRITE], MARKER L-1, MARKER In], SWEEP [CONT).

20.Adjust A3A9R57 T/H GAIN for GAIN for MARKER A level indication as indicated by CRT annotation of 100 *O.l dB.

2 1. Key in @?i) TRACE A [MAX) b.

22.Adjust A3A9R39 GPOS for MARKER A level indication as indicated by CRT annotation of 100 fO.l dB.

23.Key in [SHIFT) TRACE A (VIEW) d.

Adjustments 3-143

24.Track and Hold Adjustments

24.Adjust A3A9R52 GNEG for MARKER A level indication as indicated by CRT annotation of 100 ho.1 dB.

25.Repeat steps 4 through 24 until no further adjustments are required.

3-144 Adjustments

25. Digital Storage

Display

Adjustments

Reference

Description

Equipment

Procedure

25. Digital Storage Display Adjustments

A3A 1 Trigger

A3A2 Intensity Control

A3A3 Line Generator

First, preliminary CRT graticule adjustments are performed to position the graticule on the CRT. These preliminary adjustments assume that repair has been performed on the associated circuitry. If no repair

has been performed on the assemblies listed under REFERENCE, the preliminary adjustments are not necessary.

Next, the Sample and Hold Balance adjustments are performed. The horizontal and vertical Offset and Gain adjustments are performed, then the final CRT graticule adjustments are performed.

Last, the CRT annotation adjustments are performed to place the CRT annotation in proper location with respect to the CRT graticule.

DIGITAL VOLTMETER

Figure 3-89. Digital Storage Display Adjustments Setup

Digital Voltmeter (DVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3456A

Digitizing Oscilloscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 54501A

1.Place instrument upright as shown in Figure 3-89 with top and A3 Digital Storage cover removed.

2.Set LINE switch to ON and press [INSTR PRESET]

Preliminary Graticule

Adjustments

3.Press TRACE A Cm].

4.Adjust A3A3R4 X GAIN and A3A3R5 Y GAIN to place graticule information completely on CRT. See Figure 3-90 for location of adjustment.

Adjustments 3-145

2 5 . Digital Storage Display Adjustments

A3A2

A3Al

Figure 3-90. Location of Digital Storage Display Adjustments

5.Adjust A3A2R12 LL THRESH fully clockwise. See Figure 3-90 for location of adjustment.

6.Adjust A3A3R6 XLL so that horizontal graticule lines just meet the vertical graticule lines at the left and right sides of the graticule. See Figure 3-90 for location of adjustment.

7.Adjust A3A3R9 YLL so that vertical graticule lines just meet the horizontal graticule lines at the top and bottom of the graticule. See Figure 3-90 for location of adjustment.

8.Repeat steps 6 and 7 until horizontal and vertical lines are adjusted so that they meet the edges of the graticule but do not overshoot.

9.Adjust A3A2R12 LL THRESH fully counterclockwise.

10.Adjust A3A3R7 XSL so that horizontal graticule lines just meet the vertical graticule lines at the left and right sides of the graticule.

11.Adjust A3A3R8 YSL so that the vertical graticule lines just meet the horizontal graticule lines at the top and bottom of the graticule.

12.Repeat steps 10 and 11 until horizontal and vertical graticule lines are adjusted so that they meet at the edges of the graticule but do not overshoot.

3-146 Adjustments

Sample and Hold

Balance Adjustments

25.Digital Storage Display Adjustments

13.Set LINE switch to STANDBY.

14.Place A3A3 Line Generator on extender boards.

15.Set LINE switch to ON. Press QNSTR PRESET].

16.Key in C-1 0 ??? (RECORDER LOWER LEFT) 0 [Hz). Press [SHIFT] 0 1 (RECORDER UPPER RIGHT) 1028 a.

17.Connect oscilloscope to A3A3TP4.

18.Connect A3A3TPll to oscilloscope External Trigger Input and adjust oscilloscope controls for display as shown in Figure 3-91.

19.Adjust A3A2R50 X S&H BAL for minimum de offset between the level of the signal inside the two pulses to the signal level outside the two pulses. Figure 3-91 shows a properly adjusted waveform. Figure 3-92 shows the waveform before adjustment. Refer to Figure 3-90 for location of adjustment.

1 50.0 rnV/dlV

ioffset: 0 . 0 0 0 V

: 10.00 : I dC

~4*..,..600 ..ns

5 0 0 ns/div

4 f300.5rnV

Figure 3-91. Sample and Hold Balance Adjustment Waveforms

1 5 0 . 0 mV/dlv #offset: 0 . 0 0 0 v i 10.00 : 1 dc

4 f300.5BV

Figure 3-92. Waveform Before Adjustment

Adjustments 3-147

25.Digital Storage Display Adjustments

20.Connect oscilloscope to A3A3TP7.

21.Adjust A3A2R51 Y S&H BAL for minimum dc offset between the level of the signal inside the two pulses to the signal level outside the two pulses.

22.Set LINE switch to STANDBY.

23.Reinstall A3A3 Line Generator in instrument without extender boards.

24.Set LINE switch to ON.

X and Y Offset and 25.

Gain Adjustments 26,

Press (INSTR PRESET).

Key in [FREQUENCY SPAN] 0 Hz, [SWEEP TIME) 100 ps.

27.Disconnect cable 9 (white) from A3A9J2 and connect to A3A2J2 LG/FS test connector on A3A2 Intensity Control; the other end of the cable remains connect connected to A3A2J1.

28.Select TRIGGER [VIDEO] and adjust front-panel LEVEL control for a stable display on instrument CRT.

29.Adjust A3AlR34 SWP OFFSET so that the signal trace begins at the left edge graticule line. Refer to Figure 3-90 for location of adjustment.

30.Adjust A3A3R4 X GAIN for twenty cycles displayed on the CRT graticule. This may be made easier by adjusting A3AlR34 SWP OFFSET so that the first peak is centered on the left edge graticule line, then adjusting A3A3R4 X GAIN for two cycles per division with the twentieth cycle being centered on the right edge graticule line. A3AlR34 SWP OFFSET must then be readjusted so that the trace begins at the left edge graticule line. See Figure 3-90. for location of adjustment.

31.Remove the cable 9 (white) from A3A2J2 LG/FS test connector and reconnect to A3A9J2.

32.Remove cable 7 (violet) from A4AlJl. Short A3A9TPl to A3A9TP3 or connect an SMB snap-on short to A3A9Jl.

33.Connect DVM to A3A9TP3 and DVM ground to A3A9TPl.

34.Press LIN pushbutton.

35.DVM indication should be 0.000 kO.002 V dc.

36.Adjust A3A3R43 YOS to align the bottom graticule line with the fast sweep signal trace.

37.Remove the short between A3A9TPl and A3A9TP3 (or the SMB snap-on short) and reconnect cable 7 (violet) to A4AlJl.

38.Key in [CENTER FREQUENCY) 20 MHz. Connect CAL OUTPUT to RF INPUT. Press LOG (ENTER dB/DIv] 10 dB.

39.Connect the DVM to A4AlTP3 and the DVM ground to the IF casting.

40.Press [REFERENCE LEVEL) and adjust DATA knob and the frontpanel AMPTD CAL adjust for DVM indication of +2.000 50.002 V dc.

3-148 Adjustments

Final Graticule

Adjustments

X and Y Expand

Adjustments

25.Digital Storage Display Adjustments

41.Adjust A3A3R5 Y GAIN to align the top graticule line with the

fast sweep signal trace.

42.Press QNSTR PRESET], TRACE A @iZQ.

43.Set A3A2R12 LL THRESH fully clockwise.

44.Adjust A3A3R6 XLL and A3A3R9 YLL to align horizontal and vertical lines so that each line meets the edge line (right, left, top, or bottom) but does not overshoot.

45.Adjust A3A2R12 LL THRESH fully counterclockwise.

46.Adjust A3A3R7 XSL and A3A348 YSL to align horizontal and vertical graticule lines so that each line meets the edge line (right, left, top, or bottom) but does not overshoot.

47.Adjust A3A2R12 LL THRESH clockwise until all graticule lines switch over to long lines. This is indicated by a noticeable increase in graticule line intensity. (All graticule lines should increase in intensity.)

48.Press QNSTR PRESET).

49.Key in MARKER [NORMAL).

50.Adjust A3A3Rl X EXP to center the letter ???F??? in ???REF??? (CRT annotation in upper left corner of display) over the left edge graticule line.

51.Adjust A3A3R2 Y EXP to align the remainder of the CRT annotation so that the upper annotation (MARKER data) is above the top graticule line and the lower annotation (START and STOP

data) is below the bottom graticule line. Adjust for equal spacing above and below the graticule pattern.

Adjustments 3-149

Low-Noise DC

SUPPlY

The Low-Noise DC Supply shown in Figure 3-93 can be constructed using the parts listed in ???Ikble 3-7.

O U T P U T OVdc, t2Vdc o r +lO V d c

Figure 3-93. Low-Noise DC Supply

???Ihble 3-7. Parts for Low-Noise DC Supply

3-150 Adjustments

Crystal Filter

Bypass Network

Configuration

Crystal Filter Bypass Network Configuration

The Crystal Filter Bypass Network Configuration shown in Figure 3-94 can be constructed using the parts listed in Iable 3-8 and Table 3-9. Table 3-8 list the parts required for the construction of 21.4 MHz

IF crystal-filter bypass networks used with the A4A4 and A4A8 assemblies. Two 21.4 MHz bypass networks are required. Table 3-9 list the parts required for the construction of 3 MHz IF crystal-filter bypass networks used with the A4A7 assembly. Four 3 MHz bypass networks are required.

Figure 3-94. Crystal Filter Bypass Network Configurations

lhble 3-8.

Crystal Filter Bypass Network Configuration for A4A4 and A4A8 (21.4 MHz)

Part Value Qty. CD HP Part Number

Resistor 31.662 2 2 0698-7200

Capacitor 100 pF 2 9 0160-4801

Capacitor 910 pF 2 9 0160-6146

Receptacle - 4 1 1251-3720

lhble 3-9.

Crystal Filter Bypass Network Configuration for A4A7 (3 MHz)

Adjustments 3-151

Option 462

Introduction

This chapter contains modified performance tests and adjustment procedures for Option 462 instruments. When working on Option 462 instruments, substitute the procedures in this chapter for the standard versions contained in chapters two and three. For earlier Option 462 instruments (HP 85662A serial prefixes below 3341A) in which impulse bandwidths are specified, use the tests and adjustment under ???Impulse Bandwidths??? .The procedures included in this chapter are listed below:

6 dB Bandwidths:

Performance Tests

Test 4, 6 dB Resolution Bandwidth Accuracy Test . . . 4-2 Test 5, 6 dB Resolution Bandwidth Selectivity Test .4-10

Adjustment Procedure

A d j u s t m e n t 9 , 6 dB B a n d w i d t h A d j u s t m e n t s . 4 - 2 3

Impulse Bandwidths:

Performance Tests

Test 4, Impulse and Resolution Bandwidth Accuracy Test 4-4 T e s t 5 , I m p u l s e a n d R e s o l u t i o n S e l e c t i v i t y T e s t 4-13 Test 6, Impulse and Resolution Bandwidth Switching UncertaintyTest... ,4-16

Adjustment Procedure

A d j u s t m e n t 9 , I m p u l s e B a n d w i d t h A d j u s t m e n t s . . 4-26

Option 462 4-l

4. 6 dB Resolution

Bandwidth

Accuracy Test

Related Adjustment

Specification

Description

Equipment

Procedure

6 dB Bandwidth Adjustments

&20%, 3 MHz bandwidth

&lo%, 30 Hz to 1 MHz bandwidths + 50%, -0%, 10 Hz bandwidth

30 kHz and 100 kHz bandwidth accuracy figures only applicable 590% Relative Humidity, 540??? C.

The 6 dB bandwidth for each resolution bandwidth setting is measured with the MARKER function to determine bandwidth accuracy. The CAL OUTPUT is used for a stable signal source.

None required

1.Press ~NSTR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Key in spectrum analyzer settings as follows:

[CENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ

FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..5 MHz km, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 MHz

[REFERENCE LEVEL] .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -10 dBm

4.Press SCALE LIN pushbutton. Press [SH???FT), (my (resolution bandwidth) for units in dBm.

5.Adjust [REFERENCE LEVEL) to position peak of signal trace at (or just below) reference level (top) graticule line. Press SWEEP (SINGLE_).

6.Press MARKER [NORMAL) and place marker at peak of signal trace with DATA knob. Press MARKER @ and position movable marker

6 dB down from the stationary marker on the positive-going edge of the signal trace (the MARKER A amplitude readout should be -6.00 dB f0.05 dB). It may be necessary to press SWEEP [CONT) and adjust [CENTER FREQUENCY] to center trace on screen.

7.Press MARKER @ and position movable marker 6 dB down from the signal peak on the negative-going edge of the trace (the MARKER Aamplitude readout should be .OO dB f0.05 dB). The 6

dB bandwidth is given by the MARKER A frequency readout. (See Figure 4- 1.) Record this value in Table 4- 1.

4-2 Option 462

4. Impulse and

Resolution

Bandwidth

Accuracy Test

Related Adjustment Impulse Bandwidth Adjustments

Specification *20%, 3 MHz bandwidth

flO%, 1 MHz to 1 kHz bandwidths

-0, +50%, 300 Hz to 10 Hz (6 dB bandwidths)

Description

SYNTHESIZER

LEVEL GENERATOR

A frequency synthesizer and pulse/function generator are used to input pulses to the spectrum analyzer. The amplitude of the pulses is measured, and the impulse bandwidths are calculated for each impulse bandwidth from 3 MHz to 1 kHz. The 6 dB resolution

bandwidths are then measured using the spectrum analyzer @iZZiZK~ function. The CAL OUTPUT signal is used as a stable signal source to measure the 6 dB resolution bandwidths.

SPECTRUM ANALYZER

P U L S E / F U N C T I O N

GENERATOR

.

Figure 4-2. Impulse Bandwidth Test Setup

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Pulse/Function Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8116A

Procedure 1. Set the frequency synthesizer for a 15 MHz, + 13 dBm output. Connect the output of the frequency synthesizer to the EXT INPUT of the pulse/function generator.

2. Set the pulse/function generator controls as follows:

MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRIG

EXT INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . positive-going

EXT INPUT LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . midrange

OUTPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . pulse

LOL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .OV

HIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.4

WIDTH (WID) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 ns

DISABLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . off

4-4 Option 462

4.Impulse and Resolution Bandwidth Accuracy Test

17.Set the frequency synthesizer (FREQUENC??? Tl to 30 kHz. On the

spectrum analyzer key in [FREQUENCY SPP3011 Z, [SWEEP TIME] 0.5 seconds, SWEEP (SINGLEI), MARKER (PEAK SEARCH). Record MARKER amplitude in Table 4-2.

18. Calculate the Impulse BW of the 300 kHz filter using the formula in step 8. Record in Table 4-2.

19. Set the frequency synthesizer (FREQUENCY] to 1 MHz. Set the pulse/function generator WID to 100 ns.

20. On the spectrum analyzer key in: [RES] 100 kHz (i), lJV???DEOBW) 1 MHz, [CENTER FREQUENCY) 1 MHz, CFREQUENCY SPAN) 400 kHz, SWEEP TIME IAUTO), SWEEP @Z???F), MARKER [PEAK SEARCH]. Record MARKER amplitude in ???Ihble 4-2.

21. Set the frequency synthesizer [FREQUENCY] to 10 kHz. On the spectrum analyzer, key in: [FREQUENCY SPAN) 0 Hz, (SWEEP TIME] 0.5 seconds, SWEEP l,S???NGLEJ MARKER [PEAK SEARCH). Record MARKER amplitude in Table 4-2.

22. Calculate the Impulse BW of the 100 kHz filter using the formula in step 8. Record in Table 4-2.

23. Set the frequency synthesizer (FREQUENCY] to 300 kHz. Set the pulse/function generator WID to 333 ns.

24. On the spectrum analyzer, key in: [REs) 30 kHz (i), ~~fVll3FC.--_-l -RW)_ ., 300 kHz, CCENTER FREQUENCY) 300 kHz, [FREQUENCY SPAN] 120 kHz, SWEEP TIME IAUTO), SWEEP @GiF), MARKER, CPEAK SEARCH).

Record MARKER amplitude in Table 4-2.

25. Set the frequency synthesizer CFREQUENCY] to 3 kHz. On the spectrum analyzer, key in: (FREQUENCY SPAN] 0 Hz, ~SWEEP TIME) 0.5 seconds, SWEEP @FZF), MARKER (PEAK SEARCH]. Record MARKER amplitude in Table 4-2.

26. Calculate the Impulse BW of the 30 kHz filter using the formula in step 8. Record in Table 4-2.

27. Set the frequency synthesizer [FREQUENCY) to 100 kHz. Set the pulse/function generator WID to 1 ps.

28. On the spectrum analyzer key in @FGFBWI) 10 kHz (i), @iZGXQ 100 kHz, &ENTER FREQUENCY] 100 kHz, [FRI:QUENCY SPAN) 40 kHz, SWEEP TIME [AUTO_], SW:EEP (SINGLE), MARKER [PEAK SEARCH). Record MARKER amplitucde in ???Ihble 4-2.

29. Set the frequency synthesizer CFREQUENCV~ tn 1 kHz. On the

2 --

spectrum analyzer key in: (FREQUENCY SIm 0 Hz, [SWEEP TIME] 0.5 seconds, SWEEP CRINGLE), MARKER (PEAK SEARCH). Record MARKER amplitude in Table L1-2.

30.Calculate the Impulse BW of the 10 kHz filter using the formula in step 8. Record in ???lhble 4-2.

31.Set the frequency synthesizer [FREQUENCY) to 30 kHz. Set the pulse/function generator WID to 3.33 ps.

32.On the spectrum analyzer key in: @?X?i) 3 kHz (i), CVloEo] 30 kHz, (CENTER FREQUENCY) 30 kHz, [FREQUENCY SPAN) 12 kHz,

4-6 Option 462

4. Impulse and Resolution Bandwidth Accuracy Test

Note 6 dB resolution bandwidth measurements are used in Performance Test 5, Impulse and Resolution Bandwidth Selectivity Test.

b

HKR A 3.103 MHZ REF -9.0 dBm ATTEN 10 1290.00 dB

LINEAR

Figure 4-3. 6 dB Resolution Bandwidth Measurement

46.Select the spectrum analyzer [BW] and FREQUENCY SPAN) settings according to Table 4-3. Press SWEEP (?iKiF] and measure the 6 dB bandwidth for each resolution bandwidth setting using the procedure of steps 43 through 45 and record the value in Table 4-3. The measured bandwidths for 300 Hz, 100

Hz, 30 Hz, and 10 Hz should fall between the limits shown in the table.

4-8 Option 462

4. Impulse and Resolution Bandwidth Accuracy Test

???Ihble 4-3. 6 dB Resolution Bandwidth Accuracy

Option 462 4-9

5. 6 dB Resolution

Bandwidth

Selectivity Test

Related Adjustments 3 MHz Bandwidth Filter Adjustments 21.4 MHz Bandwidth Filter Adjustments

Step Gain and 18.4 MHz Local Oscillator Adjustments

Specification 60 dB/6 dB bandwidth ratio:

~11: 1, 3 MHz to 100 kHz bandwidths

~8: 1, 30 kHz to 30 Hz bandwidths

60 dB points on 10 Hz bandwidth are separated by ~100 Hz

Description Bandwidth selectivity is found by measuring the 60 dB bandwidth and dividing this value by the 6 dB bandwidth for each resolution bandwidth setting from 30 Hz to 3 MHz. The 60 dB points for the 10 Hz bandwidth setting are also measured. The CAL OUTPUT provides a stable signal for the measurements.

Equipment None required

Note Performance Test 4, 6 dB Resolution Bandwidth Accuracy Test, must be performed before starting this test.

4.Press MARKER C-1 and position marker at peak of signal trace. Press MARKER @ and position movable marker 60 dB

down from the stationary marker on the positive-going edge of the signal trace (the MARKER A amplitude readout should be -60.00 dB +l.OO dB). It may be necessary to press SWEEP (CONT) and adjust CCENTER FREQUENCY_) so that both 60 dB points are displayed. (See Figure 4-4.)

5.Press MARKER (7iJ and position movable marker 60 dB down from the signal peak on the negative-going edge of the signal trace (the MARKER A amplitude readout should be .OO dB f0.50 dB).

6.Read the 60 dB bandwidth for the 3 MHz resolution bandwidth setting from the MARKER A frequency readout (Figure 4-4) and record the value in ???Iable 4-4.

4-10 Option 462

5. 6 dB Resolution Bandwidth Selectivity Test

7 . Vary spectrum analyzer settings according to Table 4-4. Press SWEEP @KZF] and measure the 60 dB bandwidth for each resolution bandwidth setting by the procedure of steps 4 through 6. Record the value in Table 4-4.

8 . Record the 6 dB bandwidths from Table 4-l in ???Ikble 4-4.

9 . Calculate the bandwidth selectivity for each setting by dividing the 60 dB bandwidth by the 6 dB bandwidth. The bandwidth ratios should be less than the maximum values shown in

???fable 4-4.

10.The 60 dB bandwidth for the 10 Hz resolution bandwidth setting should be less than 100 Hz.

10 dB/

\

Figure 4-4. 60 dB Bandwidth Measurement

Option 462 4-l 1

4-12 Option 462

5. Impulse and Resolution Bandwidth Selectivity Test

1 0 aw

/

/

\

I.

Figure 4-5. 60 dB Bandwidth Measurement

4.Press MARKER In] and position the positive movable marker 60 dB down from the signal peak on the negative-going edge of the signal trace (the MARKER @J amplitude readout should be 0.00 dB *0.50 dB).

5.Read the 60 dB bandwidth for the 3 MHz resolution bandwidth setting from the MARKER Ia] frequency readout (see Figure 4-5) and record the value in Table 4-5.

6.Select the spectrum analyzer @iE%V], ~FREQUENCY SPAN), and CV???DEO] according to Table 4-5. Measure the 60 dB bandwidth for each resolution bandwidth setting by the procedure of steps 3 through 5 and record the value in ???fable 4-5.

7.Record the 6 dB bandwidths for each resolution bandwidth setting from Table 4-3 in Table 4-5.

8.Calculate the bandwidth selectivity for each setting by dividing the 60 dB bandwidth by the 6 dB bandwidth. The bandwidth ratios should be less than the maximum values shown in ???fable 4-5.

9.The 60 dB bandwidth for the 10 Hz resolution bandwidth setting should be less than 100 Hz.

4.14 Option 462

5. Impulse and Resolution Bandwidth Selectivity Test

???Ihble 4-5. Impulse and Resolution Bandwidth Selectivity

Option 462 4-l 5

6. Impulse and

Resolution

Bandwidth

Switching

Uncertainty Tkst

Related Adjustment 3 MHz Bandwidth Filter Adjustments

21.4 Bandwidth Filter Adjustments

Down/Up Converter Adjustments

Specification f2.0 dB, 10 Hz bandwidth f0.8 dB, 30 Hz bandwidth

f0.5 dB, 100 Hz to 1 MHz bandwidth * 1 .O dB, 3 MHz bandwidth

30 kHz and 100 kHz bandwidth switching uncertainty figures only applicable 190% Relative Humidity.

Description The CAL OUTPUT signal is applied to the input of the spectrum analyzer. The deviation in peak amplitude of the signal trace is then measured as each resolution bandwidth filter is switched in.

Equipment None required

Procedure 1. Press ~NSTR PRESET).

2.Connect CAL OUTPUT to SIGNAL INPUT 2.

3.Key in the following control settings:

4. Press LOG [ENTER dB/otv_) and key in 1 dB. Press MARKER

(PEAK SEARCH) a].

5.Key in settings according to Table 4-6. Press MARKER

[PEAK SEARCH) at each setting, then read the amplitude deviation from the MARKER [nl readout at the upper right of the display (see Figure 4-6).The allowable deviation for each resolution bandwidth setting is shown in the table.

4-16 Option 462

6. Impulse and Resolution Bandwidth Switching Uncertainty Test

Figure 4-6. Bandwidth Switching Uncertainty Measurement

T&ble 4-6. Bandwidth Switching Uncertainty

Option 462 4-17

4-18 Option 462

Test 4. Impulse and Resolution Bandwidth Accuracy Test (p/o ???Ihble 2-19, Performance Test Record)

Test 4. Impulse and Resolution Bandwidth Accuracy Test (p/o able 2-19, Performance Test Record)

Steps 1 through 38. Impulse Bandwidth Accuracy

Option 462 4-19

Test 4. Impulse and Resolution Bandwidth Accuracy Test (p/o ???Ihble 2-19, Performance Test Record)

Steps 39 through 46. 6 dB Resolution Bandwidth Accuracy

Res

BW

4-20 Option 462

Test 5. 6 dB Resolution Bandwidth Selectivity (p/o lkble 2-19, Performance Test Record)

Test 5. 6 dB

Resolution

Bandwidth Selectivity (p/o ???lhble 2-19, Performance lkst Record)

Step 9. 6 dB Resolution Bandwidth Selectivity

Option 462 4-21

Test 5. Impulse

and Resolution

Bandwidth

Selectivity (p/o

I)dble 2-19,

Performance T&t

Record)

Steps 5 through 9. Impulse and Resolution Bandwidth

Selectivity

4-22 Option 462

Test 6. Impulse and Resolution Bandwidth Switching Uncertainty (p/o ???Ikble 2-19, Performace Test Record)

???l&t 6. Impulse and Resolution Bandwidth Switching Uncertainty (p/o Table 2-19, Performace lkst Record)

-

Step 5. Impulse and Resolution Bandwidth

Switching Uncertainty

Option 462 4-23

9. 6 dB Resolution

Bandwidth

Adjustments

Reference IF-Display Section

A4A9 IF Control

Related Performance 6 dB Resolution Bandwidth Accuracy Test

Test

Description The CAL OUTPUT signal is connected to the RF INPUT. Each of the adjustable resolution bandwidths is selected and adjusted for the proper bandwidth.

Equipment No test equipment is required for this adjustment.

Procedure 1. Position the instrument upright and remove the top cover.

2.Set the LINE switch to On, press (INSTR PRESET) and select

SIGNAL INPUT 1.

3.Connect CAL OUTPUT to SIGNAL INPUT 1.

4.Key in (CENTER FREQUENCY) 100 MHz, [FREQUENCY SPAN) 5 MHz

(-13 MHz, and ILIN_).

5.Press [REFERENCE LEVEL) and adjust the DATA knob to place the signal peak near the top CRT graticule. The signal should be centered about the center line on the graticule.

6.Press PEAK SEARCH , MKR + a, and MARKER (al.

7.Using the DATA knob, adjust the marker down one side of the display signal to the 6 dB point; CRT MKR A annotation indicates

.500 x

8.Adjust A4A9R60 3 MHz for MKR In] indication of 1.5 MHz while maintaining the marker at .500 X using the DATA knob. Refer to Figure 4-7 for the adjustment location.

9.Press MARKER [nl. Adjust the marker to the 6 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00 X. There are now two markers; one on each side of the signal at

the 6 dB point.

10.CRT MKR A annotation now indicates the 6 dB bandwidth of the 3 MHz bandwidth filter. The bandwidth should be 3.00 MHz *0.60 MHz

11.Key in (REsBW) 1 MHz, CFREQUENCY SPAN) 2 MHz, (PEAK SEARCH),

and [MKR). If necessary, readjust by pressing

PREFERENCE LEVEL) and using the DATA knob to place the signal

peak near the top of the graticule.

12. Press MARKER IOFF) then MARKER a.

4-24 Option 462

9.6 dB Resolution Bandwidth Adjustments

13.Using the DATA knob, adjust the marker down one side of the display signal to the 6 dB point; CRT MKR A annotation indicates

.500 x.

\

~000000000000000000 n 000000000000000000 r

A4A9

Figure 4-7. Location of Bandwidth Adjustments

14.Adjust A4A9R61 1 MHz for MKR A indication of 500 kHz while maintaining the marker at 0.500 X using the DATA knob. Refer to Figure 4-7 for the adjustment location.

15.Press MARKER @. Adjust marker to the opposite side of the signal (CRT MKR A annotation indicate 1.00 X). There are now two markers; one on each of the signal at the 6 dB point.

16.The CRT MKR A annotation now indicates the 6 dB bandwidth of the 1 MHz bandwidth filter. The 6 dB bandwidth should be 1.00 MHz *O.lO MHz.

17.Key in (RES) 300 kHz, ~FREQUENCY SPAN) 500 kHz,

[PEAK SEARCH), and C-1. If necessary, readjust by pressing [REFERENCE LEVEL]] and using the DATA knob to place the

signal peak at the top of the graticule.

18.Press MARKER m then MARKER (iYJ

19.Using the DATA knob, adjust the marker down one the displayed signal to the 6 dB point; CRT MKR A annotation indicates .500 X.

20.Adjust A4A9R62 300 kHz for MKR A indication of 150 kHz while maintaining marker at .500 X using the data knob. Refer to Figure 4-7 for location of adjustment.

21.Press MARKER In]. Adjust the marker to the 6 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00

Xl*

22.The CRT MKR A annotation now indicates the bandwidth of the 300 kHz bandwidth filter. The bandwidth should be 300.00 f30.00 kHz.

23.Key in (RES] 10 kHz, (FREQUENCY SPAN] 20 kHz, [PEAK SEARCH), and (MK-1. If necessary, readjust by pressing

[REFEREF -LEVEL) and using the DATA knob to place the signal peak near the top of the graticule.

Option 462 4-25

9.6 dB Resolution Bandwidth Adjustments

24.Press MARKER IOFF), then MARKER In].

25.Using the DATA knob, adjust the marker down one side of the displayed signal to the 6 dB point; CRT MKR annotation indicates

.500 x.

26.Adjust A4A9R65 10 kHz for MKR A indication of 5.00 kHz while maintaining the marker at .500 X using the DATA knob. Refer to Figure 4-7 for the adjustment location.

27.Press MARKER @. Adjust the marker to the 6 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00 Xl.

28.The CRT MKR A annotation now indicates the 6 dB bandwidth of the 10 kHz bandwidth filter. The bandwidth should be 10.0 fl.O kHz

29.Key in (jj) 3 kHz, (FREQUENCY SPAN] 5 kHz, (PEAK SEARCH], and [MKRJ If necessary, readjust by pressing [REFERENCE LEVEL] and using the DATA knob to place the signal peak near the top of the graticule.

30.Press MARKER m and MARKER a.

31.Using the DATA knob, adjust the marker down one side of the displayed signal to the 6 dB point; CRT MKR A annotation indicates .500 X.

32.Adjust A4A9R66 3 kHz for MKR A indication of 1.5 kHz while maintaining the marker at .500 X using the DATA knob. Refer to Figure 4-7 for the adjustment location.

33.Press MARKER In]. Adjust the marker to the 6 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00

Xl.

34.The CRT MKR (ZJ annotation now indicates the 6 dB bandwidth of the 3 kHz bandwidth filter. The bandwidth should be 3.00 f0.30 kHz

4-26 Option 462

9. Impulse Bandwidth Adjustments

9. Impulse

Bandwidth

Adjustments

Reference IF-Display Section

A4A9 IF Control

Related Performance Impulse Bandwidth Accuracy Test

Test

Description The CAL OUTPUT signal is connected to the SIGNAL INPUT 1. Each of the adjustable resolution bandwidths is selected and adjusted for the proper impulse bandwidth.

Equipment No test equipment is required for this adjustment.

Procedure 1. Position the instrument upright and remove the top cover.

2.Set the LINE switch to On, press [INSTR PRESET), and select

SIGNAL INPUT 1.

3.Connect CAL OUTPUT to SIGNAL INPUT 1.

4.Key in (CENTER FREQUENCY) 100 MHz, [FREQUENCY SPAN] 5 MHz

Cm) 3 MHz, and m.

5.Press [REFERENCE LEVEL) and adjust the DATA knob to place the signal peak near the top CRT graticule. The signal should be centered about the center line on the graticule.

6.Press [PEAK SEARCH), MKR 4 (%J, and MARKER @.

7.Using the DATA knob, adjust the marker down one side of the display signal to the 7.3 dB point; CRT MKR A annotation indicates 0.430 X

8.Adjust A4A9R60 3 MHz for MKR In] indication of 1.5 MHz while maintaining the marker at 0.430 X using the DATA knob. Refer to Figure 4-8 for the adjustment location.

9.Press MARKER In]. Adjust the marker to the 7.3 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00 X. There are now two markers; one on each side of the signal at the 7.3 dB point.

10.CRT MKR A annotation now indicates the impulse bandwidth of the 3 MHz bandwidth. Impulse bandwidth should be 3.00 MHz 50.60 MHz

11.Key in [RESBW) 1 MHz, [FREQUENCY SPAN) 2 MHz, [PEAK SEARCH),

and CMKR). If necessary, readjust by pressing

[REFERENCE LEVEL) and using the DATA knob to place the signal peak near the top of the graticule.

12. Press MARKER IOFF) then MARKER [al.

Option 462 4-27

9.Impulse Bandwidth Adjustments

13.Using the DATA knob, adjust the marker down one side of the display signal to the 7.3 dB point; CRT MKR A annotation indicates 0.430 X.

A4A9

I F C O N T R O L

\

1

Figure 4-8. Location of Bandwidth Adjustments

14.Adjust A4A9R61 1 MHz for MKR A indication of 500 kHz while maintaining the marker at 0.430 X using the DATA knob. Refer to Figure 4-8 for the adjustment location.

15.Press MARKER @. Adjust marker to the opposite side of the signal (CRT MKR A annotation indicate 1.00 X). There are now two markers; one on each of the signal at the 7.3 dB point.

16.The CRT MKR A annotation now indicates the impulse bandwidth of the 1 MHz bandwidth. The impulse bandwidth should be 1.00 MHz fO.10 MHz.

17.Key in (jjj 300 kHz, (FREQUENCY SPAN) 500 kHz,

CPEAK SEARCH), and CMKR]. If necessary, readjust by pressing [REFERENCE LEVEL]] and using the DATA knob to place the signal peak at the top of the graticule.

18.Press MARKER IOFF] then MARKER @.

19.Using the DATA knob, adjust the marker down one the displayed signal to the 7.3 dB point; CRT MKR A annotation indicates 0.430 X.

20.Adjust A4A9R62 300 kHz for MKR A indication of 150 kHz while maintaining marker at 0.430 X using the data knob. Refer to Figure 4-8 for location of adjustment.

21.Press MARKER Ia]. Adjust the marker to the 7.3 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00 Xl*

22.The CRT MKR A annotation now indicates the impulse bandwidth of the 300 kHz bandwidth. The impulse bandwidth should be 300.00 h30.00 kHz.

23.Key in @EYEiT) 10 kHz, [FREQUENCY SPAN] 20 kHz, [PEAK SEARCH), and C-1. If necessary, readjust by pressing

4-28 Option 462

9. Impulse Bandwidth Adjustments

[REFERENCE LEVEL] and using the DATA knob to place the signal peak near the top of the graticule.

24.Press MARKER IOFF), then MARKER (al.

25.Using the DATA knob, adjust the marker down one side of the displayed signal to the 7.3 dB point; CRT MKR annotation indicates 0.430 X.

26.Adjust A4A9R65 10 kHz for MKR A indication of 5.00 kHz while maintaining the marker at 0.430 X using the DATA knob. Refer to Figure 4-8 for the adjustment location.

27.Press MARKER Ia]. Adjust the marker to the 7.3 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00 Xl*

28.The CRT MKR A annotation now indicates the impulse bandwidth

of the 10 kHz bandwidth. The impulse bandwidth should be 10.0 fl . O kHz

29.Key in @E???GZT] 3 kHz, [FREQUENCY SPAN] 5 kHz, [PEAK SEARCH), and

@iiGGZQ. If necessary, readjust by pressing [REFERENCE LEVEL) and using the DATA knob to place the signal peak near the top of the graticule.

30.Press MARKER a and MARKER a.

31.Using the DATA knob, adjust the marker down one side of the displayed signal to the 7.3 dB point; CRT MKR A annotation indicates 0.430 X.

32.Adjust A4A9R66 3 kHz for MKR A indication of 1.5 kHz while maintaining the marker at 0.430 X using the DATA knob. Refer to Figure 4-8 for the adjustment location.

33.Press MARKER In]. Adjust the marker to the 7.3 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00

Xl.

34.The CRT MKR @ annotation now indicates the impulse bandwidth of the 3 kHz bandwidth. The impulse bandwidth should be 3.00 ho.30 kHz

Option 462 4-29

5

Option 857

Introduction

This chapter contains a modified performance test for Option 857 instruments. When working on Option 857 instruments, substitute the procedure in this chapter for the standard version contained in Chapter 2. The procedure included in this chapter is listed below:

Performance Tests

Test 12, Amplitude Fidelity Test.. . . . . . . . . . . . . . . . . . . . . . . . .2-43

Option 857 5-1

12. Option 857

Amplitude Fidelity

Test

Related Adjustment Log Amplifier Adjustments

Specification Log:

Incremental

fO.l dB/dB over 0 to 80 dB display

Cumulative

3 MHz to 30 Hz Resolution Bandwidth:

54~0.6 dB max over 0 to 70 dB display (20 - 30??C). sf1.5 dB max over 0 to 90 dB display

10 Hz Resolution Bandwidth:

sf0.8 dB max over 0 to 70 dB display (20 - 30??C). sk2.1 dB max over 0 to 90 dB display

Linear:

&3% of Reference Level for top 9-l/2 divisions of display

Description Amplitude fidelity in log and linear modes is tested by decreasing the signal level to the spectrum analyzer in 10 dB steps with a calibrated signal source and measuring the displayed amplitude change with the analyzer???s MARKER A function.

BNC TEE

Figure 5-1. Option 857 Amplitude Fidelity Test Setup

5-2 Option 857

12. Option 857 Amplitude Fidelity Test

Equipment Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 3335A Adapter, Type N (m) to BNC (f) . . . . . . . . . . . . . . . . . . . . . . HP 1250-0780

(2) BNC to BNC cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 10503A

Procedure Log Fidelity

1.On the spectrum analyzer, connect the CAL OUTPUT to INPUT 2. Press IRECALL) @ and adjust the FREQ ZERO pot for maximum amplitude.

2.Press (JNSTR PRESET] on the analyzer. Key in analyzer settings as follows:

( C E N T E R F R E Q U E N C Y ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 MHZ

3.Set the frequency synthesizer for an output frequency of 20.000 MHz and an output power level of + 10 dBm. Set the amplitude increment for 10 dB steps.

4.Connect equipment as shown in Figure 5-l.

5.Press MARKER [PEAK SEARCH), (jMKR), [MKR +REF LVL] to

center the signal on the display.

6.Press SWEEP I=) on the spectrum analyzer and wait for the sweep to be completed.

7.Press MARKER [PEAK SEARCH), MARKER In].

8.Step the frequency synthesizer output amplitude down 10 dB.

9.On the spectrum analyzer, press SWEEP [ml and wait until

the sweep is completed. Press MARKER [PEAK SEARCH), and record the marker A amplitude (a negative value) in column 2 of Table 5-l.

10.Repeat steps 8 and 9, decreasing the output power from the frequency synthesizer in 10 dB steps from -10 dBm to -80 dBm.

11.Subtract the value in column 1 from the value in column 2 for each setting to find the fidelity error.

Option 857 5-3

12. Option 857 Amplitude Fidelity Test

???Ikble 5-1. Log Amplitude Fidelity (10 Hz RBW; Option 857)

12. Subtract the greatest negative fidelity error from the greatest positive fidelity error for calibrated amplitude steps from -10 dB to -70 dB. The results should be 250.8 dB.

dB

13. Subtract the greatest negative fidelity error from the greatest positive fidelity error for calibrated amplitude steps from -10 dB to -90 dB. The results should be sf2.1 dB.

dB

14.Set the frequency synthesizer for output amplitude to + 10 dBm.

15.Key in the following analyzer settings:

FREQUENCY SPAN] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 kHz

;&TTiFV. , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 kHz SWEEP @?GF)

16.Press MARKER [PEAK SEARCH], [j), [MKR-IREF LVL] to center the signal on the display.

17.Key in the following analyzer settings:

18.Press MARKER A. Step the frequency synthesizer output amplitude from + 10 dBm to -80 dBm in 10 dB steps, noting

the MARKER A amplitude (a negative value) at each step and recording it in column 2 of ???fable 5-2. Allow several sweeps after each step for the video filtered trace to reach its final ampltitude.

19.Subtract the value in column 1 from the value in column 2 for each setting to find the fidelity error.

5-4 Option 857

12. Option 857 Amplitude Fidelity Test

20.Subtract the greatest negative fidelity error from the greatest positive fidelity error for calibrated amplitude steps from -10 dB to -70 dB. The results should be SO.6 dB.

dB

21.Subtract the greatest negative fidelity error from the greatest positive fidelity error for calibrated amplitude steps from -10 dB to -90 dB. The results should be 1.1.5 dB.

dB

???Ihble 5-2. Log Amplitude Fidelity (10 kBz RBW; Option 857)

23.Set the frequency synthesizer for an output power level of + 10 dBm.

24.Press SCALE LIN pushbutton. Press MARKER

[PEAK SEARCH_),(MKR) to center the signal on the display.

25.Set (FREQUENCY SPAN) to 0 Hz and CV???DEOBW) to 1 Hz. Press (SHIFT), m (resolution bandwidth), MARKER a].

26.Decrease frequency synthesizer output amplitude by 10 dB steps,

. noting the MARKER A amplitude and recording it in column 2 of ???Iable 5-3.

Option 857 5-5

12. Option 857 Amplitude Fidelity Test

???lhble 5-3. Linear Amplitude Fidelity

5-6 Option 857

Performance Test

Record

Option 857 5 - 7

Test 12. Option

857 Amplitude

Fidelity Test

Step 9. Log Amplitude Fidelity (10 Bz RBW; Option 857)

5-E Option 857

Test 12. Option 857 Amplitude Fidelity Test

Step 26. Linear Amplitude Fidelity

Option 857 5 - 9

6

Major Assembly and Component Locations

IF-Display Section

Figure Index

Major Assembly and Component locations 6-l

RF Section Figure

Index

W24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 W25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 W26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 W27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 W28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 W29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 W32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7

A5AlJl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5Al . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5A2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5A3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5A4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5A5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5ATl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5Jl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A5J3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A5J4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A5Kl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5Rl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A5Sl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..6-2. 6-3 A6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A l l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 Al2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 Al5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 Al6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 Al7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 Al8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23Al . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A23A2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A23A3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 A23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23Al . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23A2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23A3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23A4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23A5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23A6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23ATl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A23AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3 A26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-l A26Fl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

6-2 Major Assembly and Component locations

Major Assembly and Component locations 6-3

w43

c5

c4

c3

c2

A26

/

c

Figure 6-l. RF Section, Top View

6-4 Major Assembly and Component locations

ASA A543 W2 45A2 A5A 1 A5AlJl W42 A5Rl

Figure 6-2. RF Section, Front View

Major Assembly and Component locations 6-5

A26

Figure 6-3. RF Section, Bottom View

6-6 Major Assembly and Component locations

AlAlOCl

AlAlOC4 \ AlA AlA A r8 AlA FLi AITI

\.\ \ I ???i

AlAlOC2

AlAlOC3

A4A9

AlA

W7

A4A8

A4A7

A4A6

Figure 6-4. IF Section, Top View (SN 3001A and Below)

Major Assembly and Component locations 6-7

AlAlOC4

AlAlOC2

AlAlOC3

A4A3

w21

A4A8

A4A7

A4A6

A4A5

A4A4

A4A3

A4A2

A4Al

AlA

AlVl

AlA

i ???A3Al

0 0 0

>

Figure 6-5. IF Section, Top View (SN 3004A and Above)

6-8 Major Assembly and Component locations

AlVl

,w3

w9

Figure 6-6. IF Section, Front View

Major Assembly and Component locations 6-9

AlAlO

I/??? AA

/w2g

/W24

A4AlO

W28

/

W8

???W23

???W32

( S N 3004A a n d a b o v e )

\ AlVl

A3AlO

/ I

W24 w23

Figure 6-7. IF Section, Bottom View

6-10 Major Assembly and Component locations