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Michael A. Terrell

wrote:

"Are we having fun yet? "

Getting there.

"If you looked at a pile of dead TM500 stuff from the FG507 era,
it's likely that ZERO of them died from bad caps. "

I read the OP. It didn't die. It fails to start. There is a difference. If you think I was recommending a bunch of caps be changed at random you are mistaken. Any digital thing need proper reset and Vcc or Vdd or whatever to run. If it is not there initially it will never run. If there eventually it will run forever, but only gets one chance to start.

That's what I read in the OP. Also, being the type of equipment it is, it's not likely to be a bunch of caps, just one. It is most likely from the description in the OP. I would be looking at whatever feeds the microprocessor(s) and the associated reset circuits, unless they are all internal. That would be my first thing to do, even though it is not a common failure. (of course it is possble the OP already looked into that)

I have an intenet filter in my brain. When someone writes something I know that it is just one person saying it and they could be worng, as can I. Maybe I should have phrased it differently, maybe others do not have that automatic filter. You save alot of keystrokes by not including all the "maybe", "could be" and all that every time. I thought it was a foregone conclusion that it was just a suggestion.

I never claimed to have fixed one of those generators with the exact same symptom and it was C XXX or whatever.

This is not worth an argument really. I will just take note of what you wrote and perhaps phrase things a bit differently in the future.

We had our own calibration lab at Microdyne, and they replaced a lot
of electrolytic capacitors in test equipment. That function generator
is decades old, and a lot of places left test equipment powered up 24/7
so those failures are to be expected. Some factories aren't air
conditioned, ao that shortens the life even more.