Gibson GA5T 1967 - help! Stopped working after cap replace

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d.g.bowen
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Joined: Thu Jan 17, 2013 4:15 am

Gibson GA5T 1967 - help! Stopped working after cap replace

Post by d.g.bowen »

I have an all original 1967 GA5T - startedto hum with volume at zero, filter caps. Replaced, all worked well. Should have stopped there BUt, like an idiot, I just had to keep going. I replaced the 2 x .01 mfd Sprague black beauties with orange drops as well as the 10 mFd sprague polar. Now, no sound (barelt audible) Checked all my work vs schematic, stupid mistakes. When the amp is on, I get DC voltage in the 160 range on one side of one of the orange drops and zero on the other side, second orange drop is 190 on one side abd 7 VDC on the other - a little leakage? I've never installed a bad orange drop (new) but Isuppose anything is possible. Any advice, tips, help would be greatly appreciated. Thanks in advance, Dan.
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martin manning
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Re: Gibson GA5T 1967 - help! Stopped working after cap replace

Post by martin manning »

You should see ~0V on the power tube side of both caps. Leakage or some wiring fault could be the cause. Can you put the original caps back? If they weren't leaking, there's no reason to replace them.
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