Today I had to service my Keithley 2100 (aka "fake" Keithley as these are just an Array M3500A rebadger).
In fact I have serviced this device in the past - the electrolytics had given out (on a 2012 device - go figure).
But this time I noticed my resistance measurement going flaky - presumably the banana jacks.
Upon opening the device I noticed two things:
- one of the formerly changed capacitors had bulged its top (again)
- I could not seem to get good access to the banana jack block or immediately notice a problem
So I begrudgingly proceeded to take the device apart. Upon finishing the removal of the PCB from the device (it was not too bad really)
and closer inspection I again noticed two things:
- the deceased capacitor seemed to be installed by me with reversed polarity
- the problem with the banana jack block seemed to be one solder joint on the pcb - both things accessible without removing the pcb
What more is there to say - the device is back together and seems to work again.