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hugeshows hugeshows is offline
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Default Restoring a Sherwood S-5000

I'm trying to dig up my notes on some of the S-5000s I've done before. I am having a hard time remembering exactly what the volts came up to after re-capping, but I seem to think that your number is quite high.

It is likely that our differences are a result of line voltage, the fact that I've still got old caps in mine, or both. I will do some more measurement soon and see if I can come up with a reason. Our units are pretty close in serial numbers. I can't tell off hand if those repairs in there were done correctly, they look a tad sloppy... But I would expect other problems to arise very quickly at those voltages if something was really wrong in there.

But 470v is a LOT higher than any 7189 is rated for, by about 30v... So yeah, no wonder you arced over some tubes in there. Frankly, I'm a bit surprised the ones you have in there now can handle it.

Anyway, we both have some more measuring to do. I'm curious about your line voltage. Let's start there.. Maybe yours is abnormally high and mine abnormally low...

-forkinthesocket

No tubes were removed, the amp was at idle with about 10 minutes warm-up time.

I'll take a look at the AC HV tonight.



Oh, and I don't suppose there is a line voltage selection of any time is there? If it was tapped for 110VAC that might explain it. I get something close to 120-125 VAC here.



I have a variac, and so I will put it inline and see what it takes to get them lower. I guess I should look at AC filament voltages too?



--John