U2000 B+ unstable?

pun84

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I've had this U2000 broken on my shelf for a while now.. Tested the power supply with a bulb, works fine.. Found a shorted HOT and changed it..

Now the B+ was set to 126-127V, and the chassis seems fine.. however when I power it up cold again the next day (on my variac) the B+ shoots up to 140-150V+ and the B+ adj pot doesn't change B+ at all..

Then i'll cycle the power off and the B+ will be normal again at 127V and adjustable via the pot... I checked the flyback, it seems okay.. not sure where to go from here though

any ideas?

thanks
 
Figured it out.. either a hairline crack or cold solder joint on T101 or Q101 pins.. as well as some of the smaller low watt resistors surrounding the area was causing the B+ to go super high.

Found the trouble area by tapping the chassis with a sharpie marker =]
 
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