The battery is only for the SRAM which holds? the power on settings for example? ?No calibration is impacted.
Calibration data is in the EEPROM on the processor board.? Usually a good idea to make a copy of that data.? That device is socketed since it needs to move over if the processor board is replaced.
The biggest concern about corrupting? the alignment data in that EEPROM is for the RF Input assembly.? ?Some of the other assemblies have the calibration data on the assemblies themselves ( 8920B and 8924 ) using a small serial EEPROM
Usually verify the RF Input? alignment data by jumpering the tracking gen out to the antenna in using the SA mode and the full 1Ghz span.? Should be pretty flat if the alignment data is intact and the RF input is working correctly.? +-4db flatness across the span should be good enough.? The level should match the tracking gen? output setting but if the average level is off that may be an SA? level adjustment.? ?Usually affects from 380-1000 Mhz with the varactor tuning used in that range if the EEPROM data is wrong.
That step is done on top of the normal diagnostics before anything else is looked at.
