Keysight Technologies N5247B, Service Manual

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Keysight N5247B Service Guide 4-41
Troubleshooting
Measurement System Troubleshooting
setting. For analyzers with DSP version 4.0, the signal is 7.61 MHz above
the network analyzer setting. For analyzers with DSP version 5.0, the
signal is 7.44 MHz above the network analyzer setting
6. If the signal is not present but the signal is present, from “Checking the
A15 13.5 GHz LO Synthesizer Output” (S/N prefixes
<
6021) or “Checking
the A15 Direct Digital Synthesizer (DDS) Assembly Outputs” (LO Output,
prefixes
≥
6021), replace the A25 HMA 26.5. Refer to “Removing and
Replacing the A25 HMA26.5” on page 7-36 .
7. If the signal is present, reconnect cable W52 or W80 and then:
— for 2-port models, continue checking with “Checking the Receiver
Group” on page 4-52 .
— for 4-port models, continue checking with “Checking the A26
Splitter Output” .
Verify the Model/Version of HMA26.5 Installed
The installed components in your PNA model may be either using the legacy
HMA26.5 part number 5087-7765 or if your PNA is using the newer HMA26.5
part number N5240-60101.
Legacy HMA26.5 Use the Following Components:
— A22 splitter 5087-7139
— W42 N5222-20009
— W43 N5222-20007
— W44 N5222-20008
The new N5240-60101 HMA26.5 has the splitter integrated into the assembly
and uses an N5222-20126 cable. Refer to Figure 4-12 on page 4-42 .
See also Chapter 6, “Replaceable Parts.” and the “Bottom Assemblies and
Cables” section for your configuration and serial number prefix.