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Chapter 5
Troubleshooting the IF Section
IF Power-Level Measurement
IF Power-Level Measurement
The following measurement procedures are used for troubleshooting
along the 21.4 MHz IF signal path from the A9 third converter
assembly, through the IF section, to output of the A14 log amplifier
assembly.
To calibrate the reference level of the analyzer, the CAL AMPTD
self-calibration routine adjusts the gain of the 21.4 MHz IF variable
amplifier on the A9 assembly and mathematically offsets the digitized
video signal on the A16 processor/video assembly. Due to component
variations it is unlikely that any two analyzers will have the same
21.4 MHz IF signal level for the same instrument settings.
Furthermore, a defective analyzer may produce misleading IF signal
levels if the CAL AMPTD routine has been run.
An IF test board is used in the following procedures to simplify
troubleshooting. The test board is used to isolate the RF section from
the IF section and allows the testing of individual IF assemblies. Refer
to
Chapter 15, “Service Equipment and Tools”
the IF test board.
To set up the instrument for an IF power-level
measurement
The power levels provided with the measurement procedures in this
section are accurate when the following steps are followed.
1. Ensure that the CAL OUT amplitude is within specification. Refer to
the calibrator amplitude performance test in the 8590 E-Series and
L-Series Spectrum Analyzers User's Guide or 8591C Cable TV
Analyzer User's Guide, Spectrum Analyzer Reference.
2. Connect the CAL OUT signal to the RF input using the CAL cable.
3. Press
PRESET
on the analyzer, then wait for the preset routine to
finish. Set the analyzer by pressing the following keys.
FREQUENCY
, 300,
MHz
SPAN
, 0,
Hz
Summary of Contents for 8590L
Page 29: ...30 Chapter1 Introduction If You Replace or Repair an Assembly ...
Page 175: ...176 Chapter2 Making Adjustments 28 Correcting for Absolute Amplitude Accuracy for Option 051 ...
Page 279: ...280 Chapter5 Troubleshooting the IF Section Troubleshooting the A15 Motherboard Assembly ...
Page 347: ...348 Chapter7 Replacing Major Assemblies Rear Frame Assembly ...
Page 355: ...356 Chapter8 If You Have A Problem Returning Your Analyzer for Service ...
Page 379: ...380 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
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Page 381: ...382 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
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Page 383: ...384 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
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Page 385: ...386 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
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Page 387: ...388 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
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Page 389: ...390 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
Page 390: ......
Page 391: ...392 Chapter9 Assembly Descriptions and Block Diagrams IF Section ...
Page 392: ...393 10 Analyzer Options and Block Diagrams ...
Page 443: ...444 Chapter10 Analyzer Options and Block Diagrams Option 190 DVB C Service Menus ...
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Page 445: ...446 Chapter10 Analyzer Options and Block Diagrams Option 190 DVB C Service Menus ...
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Page 447: ...448 Chapter10 Analyzer Options and Block Diagrams Option 190 DVB C Service Menus ...
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Page 449: ...450 Chapter10 Analyzer Options and Block Diagrams Option 190 DVB C Service Menus ...
Page 451: ...452 Chapter10 Analyzer Options and Block Diagrams Option 190 DVB C Service Menus ...
Page 483: ...484 Chapter11 Major Assembly and Cable Locations Major Assembly and Cable Locations ...
Page 537: ...538 Chapter12 Replaceable Parts Component Level Information Packets ...
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Page 539: ...540 Chapter12 Replaceable Parts Component Level Information Packets ...
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Page 541: ...542 Chapter12 Replaceable Parts Component Level Information Packets ...
Page 542: ...FOLDOUT 12 3 8590L AND 8591E RF ASSEMBLY ...
Page 543: ...544 Chapter12 Replaceable Parts Component Level Information Packets ...
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Page 545: ...546 Chapter12 Replaceable Parts Component Level Information Packets ...
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Page 547: ...548 Chapter12 Replaceable Parts Component Level Information Packets ...
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Page 551: ...552 Chapter12 Replaceable Parts Component Level Information Packets ...
Page 665: ...666 Chapter15 Service Equipment and Tools Service Equipment and Tools ...
Page 666: ...667 16 Safety and Regulatory Information ...
Page 673: ...674 Chapter16 Safety and Regulatory Information Protection from Electrostatic Discharge ...