Keysight N5224B, Руководство по обслуживанию

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4-46 Keysight N5224B/25B Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
4. Set the network analyzer for an 800 MHz CW frequency and observe the
spectrum analyzer measurement. An 800 MHz signal should be present.
5. Refer to Note on page 4-31 . If the observed problem was frequency
banded rather than broadband related, set the analyzer frequency to the
center of the problem band. The spectrum analyzer should measure a
signal above the network analyzer 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 from “Checking the A4 and A17
Source Synthesizer Outputs” are present, replace the appropriate source
board. Refer to “Removing and Replacing the A4–A17 Boards” on
page 7-19 .
7. If the signal is present, reconnect all cables, and then continue with
“Checking the A7, A8, A12, and A13 50 GHz Doubler Outputs” .
Checking the A7, A8, A12, and A13 50 GHz Doubler Outputs
1. Refer to the block diagram at the end of this chapter and to “Top
Assemblies and Cables, All Options, Serial Number Prefixes <6021” on
page 6-19 . Locate cable W11 on the A7 doubler board, cable W17 on the
A8 doubler board, cable W13 on the A12 doubler board, and cable W15 on
the A13 doubler board. (A12 and A13 are only available in 4-port models
and 2-port models with Option 224.)
2. Disconnect cable W11 or W17 or W13 or W15, dependent 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 network analyzer for an 800 MHz CW frequency and observe the
spectrum analyzer measurement. An 800 MHz signal should be present.
5. Refer to the Note on page 4-31 . If the observed problem was frequency
banded rather than broadband related, set the analyzer frequency to the
center of the problem band. The spectrum analyzer should measure a
signal above the network analyzer 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 from “Checking the A4 and A17
Source Synthesizer Outputs” are present, replace the appropriate doubler
board. Refer to “Removing and Replacing the A4–A17 Boards” on
page 7-19 .
7. If the signal is present, reconnect all cables, and then continue with
“Checking the Signal Separation Group” on page 4-47 .