Hi all, long time no see. I have a VS8080 in the shop and the output sticks, humming, to the negative rail for a few seconds on startup, then with a pop it settles and works fine. I put two new main filter caps on it and checked all the semiconductors and they give me beeps, can't find any open resistors. Before I start checking component by component is there anything you can tell me to help focus the search? Am I actually likely to be looking at a leaky TR9 or 10, for instance? TR10 sees most of the -ve rail voltage on its base whilst it's sticking, as I guess you'd expect, I'm wondering whether the poor thing is just strained. If so, any ideas for a replacement pair? I stock 2STA1962/2STC5242, these should be ok?
Schematic attached. Thanks very much in advance.8080___8100_Power_stage.pdf
Schematic attached. Thanks very much in advance.8080___8100_Power_stage.pdf
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