Textronix AM503B codes

[davidsrsb]

My current probe amplifier has died.
Does anybody know what code 355 means on an AM503B current probe amplifier?

 

[davidsrsb]

I had a quick look inside and there are two +5, -5, +15 and -15 regulators, all working.
There is a 1.5V battery that has gone flat and leaked.
No sign of dry joints or burning.

 

[poobah]

Dave,

I have plenty of the old style (pure analog) AM503's if that would help. Can't help you fixing the digital unit though.

I'll bet that battery was there to maintain calibration coefficients in RAM as this was designed before FLASH memories came into being.

 

[davidsrsb]

I fitted a new battery and the error code went away. Now the degauss and probe open warning do not work. I don't think the probe is being detected

 

[poobah]

Does it measure now? I'll bet your out of calibration...

Probably have to send it back to TEK... There might be a couple of pins somewhere you can connect to force the unit to reload it's bios and default calibration coefficients from ROM.

Can you find a schem?

 

[anatech]

Well, if it goes back to Tek, at least it'll be calibrated properly. That should last you a while.

-Chris