I do not sure about the correctnesses of the schematics not even if it is matching my PS.
So I investigated the supply further and I connect a 4700µF Capacitor in parallel to the output to see, if it helps.
Yes, this worked it out.
Now it was time to search for the C20 in the Power Supply. After some unscrewing I found it beneath the output conectors. See Pictures.
I unsoldered the C20 (2x because of double PS) and measured them with my Component tester.
Uhh, 1 has a loss factor >9% the other >7% ESR bad, too.
I did have spare capacitors at hand with old Date code '97 but they measure quite well so I gave it a try and soldered them in and made a test.
Whow! what a difference. Almost flat line on my Scope no matter what I tried.
So I hope the failure is fixed now.
I examined a few other Electrolyte C, but they all were in a good state.
Does anybody can interpret the build code for the old C's?
Interesting, that my replaced Cs are longer than the other, I do have the hope they will lasting a few years, now