Keithley 195a issues

[eyehat]

Hello everybody.  I just bought a Keithley and boy is it grand.  The d.c. volt, and ohm readings are spot on, original calibration was all that was done to it from factory.  I was quickly disheartened though, as when I pressed the button for a.c. voltages or amps it showed no op. Which after diving through the manual means that the 1950 option is not present.  My question to any one out there is what did that option consist of; is it some rom chips, a breakout board and would it be in the realm of possibility to find one and flash some roms if any body has them?

[lowimpedance]

Not a ROM change, but requires good old analogue electronics (see the manual for details).
The plug in PCB contains current shunts plus relays and other switching as well as a AD636 plus its associated parts for the TRMS part.
In short its not the easiest thing to re create (cost wise). Cheaper to buy another 195a with that option installed!.
However its still an excellent meter.
I have two, one with the option and one without.
Such a PITA having these things as 'OPTIONS', but that was the way it was done so it pays to investigate a prospective purchase to make sure it does contain options for functions you would have expected to get.

[eyehat]

Thank you for letting me know.  I wasn't too concerned with having those options, I paid $10 for it and it is a superb meter without the other options. Thats what I assumed, I'll keep an eye out for another as a donor or as another meter (I tend to hoard equipment).