Agilent Technologies N5241A, Service Manual

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4-34 Service Guide N5242-90001
Troubleshooting PNA Series Microwave Network Analyzers
Measurement System Troubleshooting N5241A/42A
Checking Port 1, 2, 3, or 4 Power Outputs (A, B, C, or D Signals)
The object of this check is to verify the power of the output signal across the entire
frequency range. Perform this test if there is an observed problem only with one receiver
trace. The ten second sweep is slow enough to allow you to observe the output power on the
power meter as the sweep occurs.
1. Connect the power sensor to the suspect port.
2. Set the trace to measure S
11
, S
22
, S
33
, or S
44
, dependent on the suspect port.
3. Observe the power reading on the power meter as the sweep occurs on the analyzer.
4. The measured output power on the power meter should be at least the preset power
level ±1 dB over the entire frequency range.
• If the measured power is correct, go to “Checking the Receiver Group” on page 4-37 .
• If the measured power is not correct, go to “Checking the Signal through the Signal
Separation Path” on page 4-34 .
Checking the Signal through the Signal Separation Path
For all of the following checks, refer to the block diagrams at the end of this chapter and to
any of the following that are appropriate:
• “Bottom Assemblies, Standard 2-Port Configuration, Option 200” on page 6-18
• “Bottom RF Cables, Standard 2-Port Configuration, Option 200” on page 6-20
• “Bottom Assemblies, 2-Port, Option 219 (including Option 029)” on page 6-24
• “Bottom RF Cables, 2-Port, Option 219 without Option 029” on page 6-26
• “Bottom Assemblies, 2-Port, Option 224 (including Option 029)” on page 6-32
• “Bottom RF Cables, 2-Port, Option 224 without Option 029” on page 6-34
• “Bottom Assemblies, Standard 4-Port Configuration, Option 400” on page 6-40
• “Bottom RF Cables, Standard 4-Port Configuration, Option 400” on page 6-42
• “Bottom Assemblies, 4-Port, Option 419 (including Option 029)” on page 6-46
• “Bottom RF Cables, 4-Port, Option 419 without Option 029 (Ports 1 and 2)” on
page 6-48
• “Bottom RF Cables, 4-Port, Option 419 without Option 029 (Ports 3 and 4)” on
page 6-52
• “Bottom Assemblies, 4-Port, Option 423 (including Option 029)” on page 6-58
• “Bottom RF Cables, 4-Port, Option 423 without Option 029 (Ports 1 and 2)” on
page 6-60
• “Bottom RF Cables, 4-Port, Option 423 without Option 029 (Ports 3 and 4)” on
page 6-64
Trace loss in the signal separation group is due to one or more of the following assemblies
being defective:
• A46, A47, A48, or A49 mechanical switch and A50 combiner (Option 224 or 423)