Keysight N5221A Service Manual page 110

Troubleshooting
Measurement System Troubleshooting
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 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 LO signal is not present and the 50 MHz reference signal is present from
50 MHz Reference Outputs,"
the A4–A13 Boards" on page
7. If the signal is present, reconnect cable W41, and then continue with
Output".
Checking the A21 HMA26.5 Output
1. Refer to the block diagram at the end of this chapter and to
Configuration, Option 400" on page
2. Disconnect W42 (4-port models) or W70 (2-port models) from the A21 HMA 26.5.
3. Connect the spectrum analyzer to the open connector on the A21 HMA 26.5.
4. Refer to the IMPORTANT notice on page
observe the spectrum analyzer measurement. For analyzers with DSP version 4.0, an 807.61 MHz signal
should be present. For analyzers with DSP version 5.0, an 807.44 MHz signal should be present.
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 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 and the signal is present from
Output," replace the A21 HMA 26.5. Refer to
7. If the signal is present, reconnect cable W42 or W70, and then:
• for 2-port models, continue checking with
• for 4-port models, continue checking with
Checking the A22 Splitter Output
1. Refer to the block diagram at the end of this chapter and to
Configuration, Option 400" on page
2. Disconnect W43 and W44, one at a time, from the A22 splitter.
3. Connect the spectrum analyzer to the open connector.
4. Refer to the IMPORTANT notice on page
and observe the spectrum analyzer measurement. For analyzers with DSP version 4.0, an 807.61 MHz
signal should be present. For analyzers with DSP version 5.0, an 807.44 MHz signal should be present.
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 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 and the signal is present from
the A22 splitter. Refer to
4-32
replace the A11 LO synthesizer board. Refer to
7-14.
6-51. Locate the flexible cable W42 at the A21 HMA26.5.
4-23. Set the network analyzer for a 800 MHz CW frequency and
"Removing and Replacing the A21 HMA26.5" on page
"Checking the Receiver Group" on page
"Checking the A22 Splitter
6-51. Locate the semi-rigid cables W43 and W44, at the A22 splitter.
4-23. Set the network analyzer for an 800 MHz CW frequency
"Removing and Replacing the A22 Splitter" on page
PNA Series Microwave Network Analyzers
"Checking the A10
"Removing and Replacing
"Checking the A21 HMA26.5
"Bottom RF Cables, Standard 4-Port
"Checking the A11 13.5 GHz LO Synthesizer
Output".
"Bottom RF Cables, Standard 4-Port
"Checking the A21 HMA26.5 Output,"
7-32.
Service Guide N5222-90001
N5221A/22A
7-30.
4-38.
replace