Keysight Technologies N5221A, Service Manual, Page: 114 / 368

4-40 Keysight N5221A/22A Service Guide
Troubleshooting
Measurement System Troubleshooting
4-
2. If the Receiver Display ( Figure 4-7 or Figure 4-8 ) is not on the analyzer
screen, perform the following: Press UTILITY , then , then
, then .
3. Set the sweep speed for a 10 second sweep: Press STIMULUS ,
then . Set the time to 10.000 seconds in the Sweep Time
box.
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 4-43 .
— If the measured power is not correct, go to “Checking the Signal
through the Signal Separation Path” on page 4-40 .
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:
— “2-Port Configuration, Option 200” on page 6-21
— “Bottom RF Cables, Standard 2-Port Configuration, Option 200” on
page 6-23
— “Bottom Assemblies, 2-Port, Option 219” on page 6-47
— “Bottom RF Cables, 2-Port, Option 219” on page 6-49
— “Bottom Assemblies, Standard 4-Port Configuration, Option 400” on
page 6-54
— “Bottom RF Cables, Standard 4-Port Configuration, Option 400” on
page 6-56
— “Bottom Assemblies, 4-Port, Option 419” on page 6-84
— “Bottom RF Cables, 4-Port, Option 419 (Ports 1 and 2)” on page 6-86
— “Bottom RF Cables, 4-Port, Option 419 (Ports 3 and 4)” on page 6-89
Trace loss in the signal separation group is due to one or more of the following
assemblies being defective:
System
Service
Utilities Receiver Display
Sweep
Sweep Time