trying to repair this Amp

[szlash280z]

Hi! I'm having trouble with my B52 amp. (apparently everyone does) My effects loop tube is giving me problems. The amp will occasionally start popping and crackling and when I jiggle the effects loop tube I can duplicate this each time. Swapping tubes makes no difference. The other day I saw this tube and the reverb tube start arcing very badly and then the amp stopped producing any sounds.

I opened it up and found some burns at the effects loop socket so I desoldered and removed the socket. I found this underneath:
[IMG611]http://i1129.photobucket.com/albums/m51 ... AG0423.jpg[/img]

it's a blown up portion of the circuit board and its obviously an open circuit now. so I repaired it like this:
[IMG612]http://i1129.photobucket.com/albums/m51 ... AG0459.jpg[/img]

There is also this damage at the phase inverter socket
[IMG612]http://i1129.photobucket.com/albums/m51 ... AG0460.jpg[/img]
I don't believe there should be contact between those circuits, so maybe I should just insulate it with something. not sure what to use there though.

I also found a leaking capacitor and open 3w resistor on the power supply circuit board. I replaced the resistor and all the large capacitors on that board.
[IMG612]http://i1129.photobucket.com/albums/m51 ... AG0462.jpg[/img]

After doing all this the Amp works and sounded great for a few plays. but now I am starting to get that popping occasionally that is duplicated when I move the effects loop tube. The damaged traces on the circuit board are the B+ circuits. I may just need to insulate the traces again as I must have some arcing there still.

I appreciate any help you can offer!

[szlash280z]

I don't know if my question was clear enough. But, I think I fixed it. I applied some lacquer over the exposed circuit board contacts. I tested the circuits and did not get any conductivity through the lacquer so it seems to be a good insulator. I didn't have anything else to try at the moment. Hopefully it won't cause problems later. I reassembled the AMP and fired it up and now I don't have any popping coming from the tube in question, even after I wiggled it a lot in the socket.

[Luthierwnc]

You should use an insulated wire. Lacquer works fine on guitar bodies but it doesn't have much insulating ability against high voltages. sh

[leadfootdriver]

I've toasted a few traces in my day!

Nice job with the solid core action.

[szlash280z]

Yeah, insulated wire would have been better. I didn't think of that at the time. The lacquer seems to be working though, so far. I only played for an hour though and it will probably melt off and cause problems in the future. At least I know that it works and will know the proper way to fix when it breaks again. I was going to use liquid electrical tape but couldn't find mine. I've never repaired electronics before so I'm pretty excited I was able to get it running again.

[Phil_S]

Since you probably don't want to undo the fix (might not be a good idea, as the board is already damaged) and replace with insulated wire, maybe you can find some high temp silicone and "paint" on enough to form an insulation substitute. Try looking in an auto parts store. The stuff for engines has to be able to take the heat. I think the lacquer is going to fail sooner or later and when it does, you can be assured it will be at the most inconvenient time. Also, you don't know what collateral damage will occur when it fails. Clean this up.

[Reeltarded]

Yes, hear what Phil said.

That solid wire doesn't burn so fast as a solder trace, nor as cold.

Be careful!