Keithley 2015 repair and the input buffer replacement.

[bdivi]

Good point on the RS232 - I will definitely give it a try.

One questions on the remote commands:

:CAL:PROT:DC:STEP3 10

The manual says the calibration voltage can be adjusted - have you tested a voltage like 10.00125 ? Is the right representation with a dot ?

Thanks

[Alex Nikitin]

Good point on the RS232 - I will definitely give it a try.

One questions on the remote commands:

:CAL:PROT:DC:STEP3 10

The manual says the calibration voltage can be adjusted - have you tested a voltage like 10.00125 ? Is the right representation with a dot ?

Thanks

Yes, you just enter the actual (known) value for the reference voltage applied in that form. I've done that correction for the Fluke 731B as I've characterised it over 18-26C range, using the needle meter to read the internal enclosure temperature instead of the battery voltage (as I don't have a battery in it). The 731B produced exactly 10.00000V at 24C with about -1ppm/C tempco (measured by a freshly calibrated HP3458A opt002). I was calibrating both 2015 at 23C read on the Fluke, so I've entered 10.00001 and -10.00001 for steps 3 and 4.

Cheers

Alex

[Macbeth]

@bdivi - Yes, you can calibrate using RS232 and specify the actual voltage, e.g. :CAL:PROT:DC:STEP3 10.00275. I can only dream of a 732 and my only externally verified ref is a Hao Qi Xin with 10.00275. My Keithley 2000 was bang on with this reference but my 2015 was out 250uV or so - but providing the actual voltage over SCPI cal and both meters now agree with each other.

A while back I got hold of a nice ESI RV622A Dekavider fairly cheap which is good for 700V and so should be able to calibrate the 100V as well as the oddball 19V ranges etc on my other meters too. I just need a stable HV supply.