Hi all,
I have an old HP 6114A. I have a few things I noticed that are wrong. I am inexperienced with vintage electronics and any input I would appreciate.
I have an imgur album here:
https://imgur.com/a/RlH44oHIt seems I can't upload the pictures here directly as they are too big.
It buzzes quite loudly from the transformer. I assume this is typical of equipment this old, correct?.
The PCB is black. I mean not the entire PCB but I have no idea what would cause this exactly. The top underside panel is darkened in two spots. In does release some heat. Is this a major issue? See the picture:
You can see the distinction here:
As for any of the capacitors, should I replace any of them? I know tantalums go bad with age. I assume they are the yellow ones axial ones? Should I just leave it till one goes? None of the caps on the top side or mains side seem budging:
Lastly, if I halfway press the 2nd digit on the decade switch or if I switch voltages around too quickly, it jumps to a random voltage different than what is selected - usually higher. The meter shows it accurately though. Sometimes when normally switching voltages it will spike instantly and go back to normal.
Would a cleaning of the decade switch usually fix this? Example:
Thanks!