Datron 4200 cal ram not writing

[essele]

I have yet another Datron calibrator challenge...

My 4000A and 4200 are in for calibration, the 4000A is apparently fine but the 4200 was out of spec but isn’t accepting the new cal values... they said ‘not keeping them’ (it may be different as the symptoms weren’t really clear on the phone call.)

The lab have suggested it might be the battery so they are trying to get me a new one, but I’m struggling to see how a battery problem would cause problems with writing cal data. There were no failures before so it’s obviously able to read something sensible so I’m assuming it’s retaining data.

I’m guessing it’s actually a ram issue or a problem with the surrounding logic ... but I won’t know for sure until it comes back and I can experiment a bit (if the new battery doesn’t fix it.)

Does anyone else see how the battery could cause this issue?

(I will probably look at putting an FRAM board together, although I probably should have done that before getting them calibrated ... not sure if I could read the old ram without causing problems.)

[maginnovision]

The only thing I can think of is it was outside the allowable tolerance but that should be apparent to them.