Peavey Blues Classic Red Plating

[Nickyfullstack]

Hey y’all I recently acquired a Peavey blues classic that has a pretty fried tube board due to tubes red plating. Gunk had. Built up on the board and made it impossible to get readings off the pins to trouble shoot the issue. Looking to see if anyone here can give me some advice. I’ve removed the tube board and confirmed all the resistors/diodes were all measuring proper. The only thing I could think of is the fried board is possibly causing the red plating? Does anyone know where I could source a board, I’ve contacted peavey seeing if they would sell me a classic 50 tube board but they are unresponsive. Here’s a pic of the board, I made an attempt to scrape some of the gunk off to see if it would help anything but the problem persisted.

[mikeydee77]

If the board is preoperly toasted then all bets are off with respect to reliability; scorched board can be conductive when faced with high voltages. Can you move the sockets to the chassis and cut away the scorched board? I have done that on one or two Classic 30s and I tihnk this model is similar ?

Basically any carbonised PCB is bad news.

[DrGonz78]

Yeah but first take some alcohol and a scrub tool to remove all that nasty looking flux. I mean that is what it looks like in the pictures. That flux could be conductive and it is in the way of seeing the really carbonized areas in the circuit board. I would say do all that and then check bias supply again.

edit: be on the lookout for things like cracked traces. It’s probably just the way it looks on camera.

[Jon Snell]

I would remove the board from the chassis, clean the board, both sides and when happy with a clean board, replace it and the first thing to do is check for -14volts on the control grids of the EL84s.

[Nickyfullstack]

Appreciate the replys! I’ll try cleaning the board with alcohol and I’ll measure for the -14v!

[Mick Bailey]

The board should clean up OK - it also looks to me like mainly flux. Don;t assume this is the cause of the red plating, though. While you're at it, take a good look at those electrolytic caps located above (Illinois caps marked IC). Inspect around the +ve end around where the lead exits the rubber seal to see of there's any crud or signs of oozing. Also check that the rubber seal isn't bulging.