Chapter 12
609
RF Section
A12 Switched Barium-Tuned Mixer (SBTX)
A12 Switched Barium-Tuned Mixer (SBTX)
The RF diagnostics routine in the adjustment/diagnostic software is
recommended for troubleshooting faults in and around A12. The RF
diagnostics will prompt you where to connect a source and another
spectrum analyzer to make RF signal level measurements.
A test board, part number 08564-69201, is connected between the A7
LOMA and A10/A12 RYTHM/SBTX ribbon cables, and the A14
frequency control assembly. DC measurements are made using the
TAM manual probe cable on several test connectors on the test board.
An 3478A DVM is used to measure the voltage across A14R91 (the
large power resistor next to A14Q404) to determine the tuning current
in the A12 preselector.
Be sure to follow all prompts precisely; failure to do so will result in
incorrect fault determinations.
Summary of Contents for 8564EC
Page 17: ...25 1 General Information ...
Page 37: ...47 2 Adjustment Diagnostic Software ...
Page 77: ...89 3 Manual Adjustment Procedures ...
Page 129: ...161 3a Manual Adjustment Procedures 3335A Source not Available ...
Page 142: ...175 4 Assembly Replacement ...
Page 194: ...Chapter 4 257 Assembly Replacement Procedure 13 A21 OCXO Figure 4 34 A21 OCXO Mounting Screws ...
Page 196: ...259 5 Replaceable Parts ...
Page 218: ......
Page 219: ......
Page 220: ......
Page 221: ......
Page 222: ......
Page 223: ......
Page 224: ...303 6 Major Assembly and Cable Locations ...
Page 234: ...315 7 General Troubleshooting ...
Page 238: ...Chapter 7 319 General Troubleshooting Introduction Figure 7 2 Ribbon Cable Connections 1 of 3 ...
Page 239: ...320 Chapter7 General Troubleshooting Introduction Figure 7 3 Ribbon Cable Connections 2 of 3 ...
Page 242: ...Chapter 7 323 General Troubleshooting Introduction Figure 7 5 Service Cal Data Menu ...
Page 271: ...352 Chapter7 General Troubleshooting Block Diagram Description Figure 7 6 Functional Sections ...
Page 283: ...364 Chapter7 General Troubleshooting Block Diagram Description ...
Page 284: ......
Page 285: ......
Page 286: ......
Page 287: ...377 8 ADC Interface Section ...
Page 291: ...Chapter 8 381 ADC Interface Section Introduction Figure 8 2 A3 Test Connector Pin Locations ...
Page 321: ......
Page 322: ...427 9 IF Section ...
Page 356: ...Chapter 9 461 IF Section A5 IF Assembly Figure 9 13 Detailed IF Adjust Signature 5 ...
Page 376: ......
Page 377: ......
Page 378: ......
Page 379: ...487 10 Controller Section ...
Page 394: ...521 11 Synthesizer Section ...
Page 451: ......
Page 452: ......
Page 453: ......
Page 454: ...593 12 RF Section ...
Page 489: ...628 Chapter12 RF Section A15 RF Assembly Figure 12 10 10 MHz TTL Reference at U304 Pin 13 ...
Page 491: ......
Page 492: ...633 13 Display Power Supply Section ...
Page 504: ......
Page 505: ...671 14 Component Level Information Packets ...
Page 507: ......