RACAL 9087

If you are trying to repair a 9087 you have a big problem.

The 9087 service manual has no technical description or schematics for the RF section just block diagrams with very little information. The manual states that the RF circuitry is in sealed units which should be replaced in the event of failure.

Signature analysis is used to determine which module is faulty and that is as far as it goes. You are expected to get a replacement module from Racal. Attenuator levels are held in ROM. Racal say if you open any of the sealed units the output levels will be off and the only way back is with Racal software and test fixture to recalibrate.