Agilent Technologies 8935 Series, Manual

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Chapter 3 81
Troubleshooting
Manual Troubleshooting Procedures (Step 4)
Swapping Known-Good Assemblies
Most swapped assemblies which use calibration data will operate well
enough with the original assembly’s calibration data to troubleshoot
and to run the diagnostics; do not expect the Test Set to meet its
specifications. Some assemblies may appear to fail because of incorrect
calibration data. It is also important to keep track of the original
assemblies in the Test Set. If calibration data is lost, the assembly will
have to be sent back to the factory.
Calibration data is generally stored in a socketed EEPROM on the
A2A31 Controller. If the controller is replaced or swapped, the original
EEPROM must be put in the new Test Set’s Controller. Should the
EEPROM lose its data, the entire instrument will require a factory
recuperation.
The assemblies that require downloaded calibration data from a
memory card are:
• A2A20 Spectrum Analyzer
• A2A33 Measurement
• A2A200 100W Attenuator
Swapping these assemblies may cause some performance specification
failures if the swapped in assembly's calibration data cannot be
downloaded.
The assemblies that require on-board calibration loaded at the factory
are:
• A2A115 Downconverter
• A2A110 Upconverter
• A2A130 RF Input/Output
• A2A44 Output Section
• A2A21 Receiver
• A2A25 Signal Generator Synthesizer
• A2A22 Receiver Synthesizer
• A2A23 Reference
Swapping these assemblies should not cause a performance problem, as
their calibration data resides with the assembly.