[sdiy] Function Generator problems

[flightofharmony]

Greetings all,

I have an old (1962) Exact electronics inc. Model 126 waveform/vcf/sweep
generator that is starting to develop some issues.
First, it started  to have a lot of 60Hz hum bleed through, so now I have to
disconnect the case ground strap if I want a clean signal.
Now it has started to drift badly in a weird way - not up or down, but a
slow oscillating fluctuation. The drift is present at startup, so I don't
think it's temperature-related, but its magnitude does seem to vary
randomly.

Does anyone have any experience with one of these?

Thanks in advance, 

~flight
http://www.flightofharmony.com