OK i checked the heaters and they were V1-2.62 V2-2.632 V3-2.620 V4-2.2 V5-2.2VDC i also checked C49+ and it was 2.642VDC
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Resurrected Peavey Triumph 60
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V4 and V4 use AC, so set your meter on AC for those two.
If you have good AC there, the problem is in the rectification that produces DC, the diodes are bad or have a bad solder joint.
If you don't have good AC at V4 or V5, the problem lies upstream. Check the schematic and measure the AC coming out of the power transformer for the heaters, I don't have my schematic handy. If that's good, then there's likely a poor connection on the wiring--those Molex connectors are terrible.
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Originally posted by nashvillebill View PostV4 and V4 use AC, so set your meter on AC for those two.
If you have good AC there, the problem is in the rectification that produces DC, the diodes are bad or have a bad solder joint.
If you don't have good AC at V4 or V5, the problem lies upstream. Check the schematic and measure the AC coming out of the power transformer for the heaters, I don't have my schematic handy. If that's good, then there's likely a poor connection on the wiring--those Molex connectors are terrible.
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OK, there's likely a bad connection somewhere. I don't have the layouts handy, so going from memory, I think the AC heater voltage went from the PT through Fuse 1. I think this is also on both legs of the hum cancel pot. Check there, following the schematic. The heater supply then goes through the top power board, then down to the power amp board, then back up to the preamp board. (again, going from memory)
I'm suspecting a bad connection on the ribbon cables between the poweramp board and the preamp board, but first you've got to make sure everything's OK on the power supply board.
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pots are clean, i went over the solder joints with my iron. found that V4 had been changed, tightened the sockets, im playin with the tubes now and the amp is still acting up. i need to get new preamp tubes i may just be swaping bad tube for better tube.
if i keep pushing the amp it will get some funny harmonics then it goes into all out feedback in all channels. the V5 tube an ecc81 made by tesla gets super hot. i put in a new electro-harmonix ecc81 and it was screaming feedback when i turned off the standby so i took it out and replaced it with another harmonix ecc81 from a different store and got the same result.
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V5 calls for a 12AX7. This is the PI, I've tried a 5751 in there (which is almost your ecc81) without those types of feedback problems (but the gain was too low).
I would check the NFB coming from the speaker jack. Find the white wire going to the speaker jacks. It should be joined with a yellow wire that goes back to the preamp board on a 3 conductor Molex plug, kinda in the center of the preamp tube board. Make sure this is connected good and that the wire is actually making contact, not broken where it pushes into the Molex plug
Check all the voltages around V5, see if they match the schematic.
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