Anyone familiar with these testers from the USA, about 1991. I have the service manual with schema but just in case anyone has dealt with repairing them, may have a few leads. The company that uses them for post-production test has only one more spare, so they would like these 3 repairing. The faults always seem to be failing to complete the POST self checks/initialisation. Often due , apparently, to sometimes static electric type voltages on production of the capacitors when they come off the line in certain situations, not normal , but can happen in rare combination of events.
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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