Mid 60s AC30

Info for maintaining and tweaking your amp to perfection.

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stratonenator
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Mid 60s AC30

Post by stratonenator » Wed Jul 31, 2019 3:08 am

I've got an AC30 copper top that wont turn on. Power is coming in butI am getting nothing from the PT. I am fairly confident that the PT is gone but it has a very weird setup with a diode going to ground. Wooden transformer, the diode has literal coins wired into either side.

PT replacement or should I dig into the diode more?
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Roe
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Re: Mid 60s AC30

Post by Roe » Wed Jul 31, 2019 2:10 pm

just test the pt
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danman
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Re: Mid 60s AC30

Post by danman » Wed Jul 31, 2019 6:17 pm

As Roe mentioned, just unsolder all secondary leads from everything including the diodes and then power up and test each pair. Measure AC voltage across both the rectifier filament pair and the other filament pair. Measure across each pair and not to ground. For the two high voltage leads, measure each one to ground to see what voltages you are getting. They will be a bit high because their is no load on the PT. Just be sure none of the bare wire ends touch the chassis or yourself during testing. You should see 6.3v AC across the two filaments, 5v AC across the rectifier filaments and somewhere around 300v AC from each hv lead to ground.

stratonenator
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Re: Mid 60s AC30

Post by stratonenator » Thu Aug 08, 2019 10:33 pm

It's got nothing coming out of the secondaries, gonna be ordering a MM Woden PT and getting this amp up and running again.
So you think your Mesa-Boogie is cool? You won't even be able to hear it over my Marshall Superlead

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