Agilent Technologies N5241A, Руководство по обслуживанию, Страница: 112 / 354

4-32 Service Guide N5242-90001
Troubleshooting PNA Series Microwave Network Analyzers
Measurement System Troubleshooting N5241A/42A
6. If the signal is not present and the signal is present from “Checking the A21 HMA26.5
Output,” replace the A22 splitter. Refer to “Removing and Replacing the A22 Splitter”
on page 7-32 .
7. If the signal is present, reconnect cables W43 and W44, and then continue with
“Checking the Receiver Group” on page 4-37 .
Checking the A4 and A13 Source Synthesizer Outputs
1. Refer to the block diagram at the end of this chapter and to “Top Cables, All Cables—All
Options” on page 6-16 . Locate either the flexible cable W1 at the A4 source 1
synthesizer board or W2 at the A13 source 2 synthesizer board. (W2 and A13 are only
available in 4-port models and 2-port models with Option 224.)
2. Disconnect W1 or W2 from J1207.
3. Connect the spectrum analyzer to J1207.
4. Set the network analyzer for a 800 MHz CW frequency and observe the spectrum
analyzer measurement. The spectrum analyzer should measure a signal at 800 MHz.
5. 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 at 7.61 MHz above the network analyzer setting.
6. If the signal is not present and the 50 MHz reference signal is present from “Checking
the A10 50 MHz Reference Outputs,” replace the faulty synthesizer board. Refer to
“Removing and Replacing the A4–A13 Boards” on page 7-14 .
7. If the signal is present, reconnect cables W1 and W2, and then continue with “Checking
the A5 and A8 Source Outputs” .
Checking the A5 and A8 Source Outputs
1. Refer to the block diagram at the end of this chapter and to “Top Cables, All Cables—All
Options” on page 6-16 . Locate the W3 and W9 cables at the A5 source 1 board or W5 and
W7 cables at the A8 source 2 board. (W5, W7, and A5 are only available in 4-port models
and 2-port models with Option 224.)
2. Disconnect the cables W3 and W9 or cables W5 and W7, dependent on the source board
to be checked.
3. Connect the spectrum analyzer to the open connector at the end of the cable that
connects to the source board to be checked.
4. Set the network analyzer for an 800 MHz CW frequency and observe the spectrum
analyzer measurement. The spectrum analyzer should measure an 800 MHz signal.
5. 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 at 7.61 MHz above the network analyzer setting.
6. If the signal is not present and the signals are present from “Checking the A4 and A13
Source Synthesizer Outputs,” replace the appropriate source board. Refer to “Removing
and Replacing the A4–A13 Boards” on page 7-14 .
7. If the signal is present, reconnect all cables, and then continue with “Checking the
Signal Separation Group” on page 4-33 .