Keysight Technologies N5247B, Service Manual

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4-46 Keysight N5247B Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
— W30 on the A63 doubler board
2. Disconnect cable W27 or W28 or W29 or W30, depending on which
doubler board is to be checked.
3. Connect the spectrum analyzer to the open connector on the doubler
board to be checked.
4. Set the PNA for an 800 MHz CW output frequency and observe the
spectrum analyzer display. An 800 MHz signal should be present.
5. Refer to the NOTE notice on page 4-29 . If the PNA problem you are
troubleshooting is frequency banded rather than broadband related, set
the PNA output frequency to the center of the problem band. The
spectrum analyzer should display a signal above the PNA 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 signals described in “Checking the A4
and A17 Source Synthesizer Outputs” on page 4-43 are present, replace
the appropriate doubler board. Refer to “Removing and Replacing the
A60–A63 70 GHz Doublers” on page 7-62 .
7. If the signal is present, reconnect all cables, and then continue with
“Checking the Signal through the Signal Separation Path” on page 4-49 .