Tektronix 492, 492P, Руководство по обслуживанию

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492/492P Service Vol. I (SN B030000 & up)
TABLE OF CONTENTS (cont)
Page Page
Section 4 MAINTENANCE (cont) Section 4 MAINTENANCE (cont)
Repairing the Crt Trace Rotation
7. Check and Calibrate
C oil.................................................
4-14
Tune Sensitivity.......................... 4-34
Front Panel Assem bly....................
4-14
8
. Conclusion................................. 4-34
Front Panel B oard.......................... 4-14
Troubleshooting Aids for the 2182 MHz
Replacing Front-Panel Push Button
Phaselocked 2nd L O ...........................
4-35
Switches.........................................
4-15
MICROCOMPUTER SYSTEM
Main Power Supply Module............ 4-15
MAINTENANCE .................................
4-36
High Voltage Power Supply............
4-16
Memory Board Option S w itc h ........ 4-36
Replacing the 1st (YIG) Local
Power-Up Self-Test Mode .............. 4-37
Oscillator Interface Board................ 4-16
Microcomputer Test M o d e .............. 4-38
Compliant Mounted Fan.................. 4-16
Instrument Bus Check M ode .......... 4-39
MAINTENANCE ADJUSTMENTS 4-19
Firmware Operating N otes.............. 4-39
110 MHz IF Assembly Return Loss
Exceptions for Firmware
Calibration.......................................
4-19
Version 8 .2 .....................................
4-40
2072 MHz 2nd Converter .......... 4-19
Exceptions for Firmware
Four Cavity F ilter........................ 4-20
Versions 8.2, 8.7 and
8 . 8
................ 4-41
M ix e r......................................... 4-20
Exceptions for Firmware
110 MHz Three Cavity Filter
4-20
Version 1.1 (492P only) .................. 4-41
829 MHz Converter Maintenance........ 4-21
Exceptions for Firmware
1. To gain acceses to the LO
Versions 1.1 and 1.2 in 492P only .. 4-42
section........................................ 4-21
Changes incorporated in
2. To gain access to the IF
Version 1.2 Firmware...................... 4-42
section.......................................
4-21
TROUBLESHOOTING ON THE
3. 719 MHz Oscillator Range
INSTRUMENT BUS ............................ 4-42
Adjustment ................................ 4-21
Instrument Bus Data Transfers
4-42
4. 829 MHz Coaxial Bandpass Filter
Instrument Bus Registers................ 4-45
Adjustment ................................ 4-22
Troubleshooting and Calibrating
the 2182 MHz Phaselocked 2nd LO . . . 4-25
Oscillator Section ................................ 4-27
1. Preparation ................................ 4-27 Section 5 THEORY OF OPERATION
2. Adjust and Check Functional and General Description . . . 5-1
Oscillator Frequency.................. 4-27 Detailed Description 5-3
3. Measure Output Power.............. 4-28
1 st Converter.................................
5-3
4. Check the 2200 MHz
RF Interface Circuits..................
5-4
Reference Mixer ........................ 4-29 RF Circuitry............................... 5-5
5. Check Tune Range .................... 4-29
2nd Converter................................. 5-6
6
. Reassembly................................ 4-29 2072 MHz 2nd C onverter.......... 5-8
Troubleshooting and Calibrating 2182 MHz Phaselocked
the 14-22 MHz Phaselock Section 2nd LO....................................... 5-10
of the 2nd LO Assembly...................... 4-30 General Description................ 5-10
1. Preliminary.................................. 4-31 2182 MHz Microstrip
2. Check Voltages.......................... 4-31
Oscillator............................... 5-10
3. Check Tune Linearity.................. 4-31 2200 MHz Reference Board .. 5-11
4. Coarse Linearity Adjustment. . . . 4-32 2200 MHz Reference Mixer .. 5-11
5. Fine Linearity Adjustm ent.......... 4-33 14-22 MHz Phaselock Board . 5-11
6
. Set the Center Frequency Cavity 2nd LO Local Oscillator..
5-12
of the 14-22 MHz Oscillator . . . . 4-34 829 MHz 2nd Converter............ 5-13
REV JUN 1.983
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