Agilent Technologies N5230A Service Manual page 106

Troubleshooting
Measurement System Troubleshooting
Source Group Tests
A defective test port switch can exhibit the same symptom as a faulty source.
NOTE
Therefore, if it is determined that the source is functioning properly, you are
directed to
Equipment Used for These Tests
Equipment Type
Spectrum analyzer
Power meter
Power sensor, 3.5 mm
RF cable, 3.5 mm (f) to 3.5 mm (f)
Getting Ready to Test
Before checking the assemblies, you must open the analyzer.
Use an antistatic work surface and wrist strap to reduce the chance of
CAUTION
electrostatic discharge for all of the procedures in this chapter.
1. Turn off the analyzer power.
2. Unplug the power to the analyzer and disconnect all rear panel connections.
3. Remove the covers from the analyzer. Refer to
WARNING Procedures described in this document are performed with power
supplied to the product while protective covers are removed. Energy
available at many points may, if contacted, result in personal injury.
4. With the covers off, plug in the analyzer and turn on the power.
Single vs. Broadband Failure
There are two main types of failures that are related to the source group. The failures are
classified as:
• broadband
• single band
Single band failures are indicated by all four channel traces having partial dropouts across
the frequency range or intermittent phase lock problems. Troubleshooting information is
provided under "If the traces faults are band-related," under
Broadband failures are indicated by all four channel traces being in the noise floor. Most
often this is due to problems in the phase lock signal path and will be characterized by a
"PHASE LOCK LOST" error message on the display.
4-36
"Checking the Signal Separation Group" on page
Models
Used With
All
All
All
All
PNA Series Microwave Network Analyzers
Model or
Part Number
8565E
E4418B/19B
8485A
85131C
"Removing the Covers" on page
"All Traces" on page
Service Guide N5230-90014
N5230A
4-42.
Alternate Model or
Part Number
None
E4418A/19A
None
Any
7-6.
4-29.