Keysight Technologies N5247B, Service Manual

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4-52 Keysight N5247B Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
3. Connect the spectrum analyzer to the open bypass switch connector. Set
the spectrum analyzer to measure a signal at 800 MHz.
4. If the 800 MHz signal is not present, replace the mechanical switch. Refer
to “Removing and Replacing the A50–A53 Bypass Switches and the A54
Combiner” on page 7-57 .
5. If the 800 MHz signal is present, replace the associated reference coupler.
Refer to “Removing and Replacing the A29 –A32 Reference Couplers and
Reference Coupler Mounting Brackets” on page 7-43 .
Checking the A70–A74 Bias Combiners
Refer to “Checking the A70/A75 Low Frequency Extension (LFE) Board and
the Bias Combiners” on page 4-47 .
Checking the Receiver Group
Equipment Used for These Tests
For all of the following checks, refer to the block diagrams at the end of this
chapter and to any of the following that are appropriate:
— “2-Port Configurations, Serial Number Prefixes <6021” on page 6-31
— “4-Port Configuration, Serial Number Prefixes <6021” on page 6-84
— “2-Port Configurations, Serial Number Prefixes
≥
6021” on page 6-58
— “4-Port Configurations, Serial Number Prefix
≥
6021” on page 6-136
Getting Ready to Test
Before checking the assemblies, you must open the analyzer.
1. Turn off the analyzer power.
2. Unplug the power to the analyzer and disconnect all front and rear panel
connections except installed jumpers.
Equipment Type Model or
Part Number
Alternate Model or Part
Number
Spectrum analyzer 8565E
856xE
a
a.
Refer to the NOTE notice on page 4-29 . Must be capable of measuring a signal at 7.61 MHz
(analyzers with DSP version 4.0), or 7.44 MHz (analyzers with DSP version 5.0), and 1 GHz.
Use an antistatic work surface and wrist strap to reduce the chance of
electrostatic discharge for all of the procedures in this chapter.