Ampeg BA115HP Output and crackling/static

[ca7922303]

R66 still measures good and it's solder joints are good?
If so, you have almost double the current running through it than normal. Measure resistance across C40 again. I would suspect you have another solder bridge somewhere that should not be.
Pictures of both sides of the board might help.

Photos

[g1]

Those pictures are large files, but poor image quality. What is the name of the resistor near the 8 pin connector on the power board that looks overheated/burnt?

[ca7922303]

Those pictures are large files, but poor image quality. What is the name of the resistor near the 8 pin connector on the power board that looks overheated/burnt?

R50(0.9k ohms) in circuit.

[g1]

Need better quality close-ups of circled area, both sides of board.

[g1]

And this area, both sides:

[x-pro]

And this area, both sides:

which Ampeg model is this photo ?

[g1]

which Ampeg model is this photo ?

It is the same model BA115HP. (edit: incorrect, picture is from a BA210SP)

[x-pro]

probably a different revision of the layout of elements on the board

[g1]

probably a different revision of the layout of elements on the board

What do you mean? That is the front panel board, not the power board.

[x-pro]

Post 259, second photo. It's different with the J28 connector
and the schematic shows a different arrangement of parts near that connector

[x-pro]

In principle, the scheme is consistent.
Therefore, as r1 asks, need a high-quality photo of the back side, where connector J28 and diodes D11, D12, C40, C39 are located.

[g1]

Ok. I see the difference now.
If he takes a picture of his unit showing the area with connector, zeners and caps, that should work.

[g1]

probably a different revision of the layout of elements on the board

Sorry, my mistake. That picture in post # 264 was from BA210SP, not HP

[ca7922303]

Need better quality close-ups of circled area, both sides of board.

Photos

[g1]

How about the trace side around the 8-pin connector on the power board.