Marshall Origin mod troubleshooting

[Ledvedder]

I'm hoping someone can help me troubleshoot issues I'm having. I've modded my Marshall Origin 20 to JCM800 spec based on this,

. I'm getting very low volume and barely any gain. I've checked all resistor and cap values, tried different tubes, checked ground points and continuity. All my voltages seem within reason. Any thoughts about areas to focus on?

This is the amp with the master and gain dimed.

eature=share

[sluckey]

Lotta collateral component damage from very sloppy soldering work on that delicate pcb. I ain't touching this!

[Ledvedder]

Lotta collateral component damage from very sloppy soldering work on that delicate pcb. I ain't touching this!

Yeah, I hear that! I've tried to clean it up as best I could.

[Latole]

I have lot of experience in soldering and working on amps. I'll never try to do some mod on this kind of circuit.

[johngovan]

The copper on this pcb is really easy to strip when soldering if you don't carefully watch the heat.

[Esquirefreak]

I'd suggest tracing the signal to see where it's lost.

That being said, this PCB and a number of components is possibly toast from soldering iron abuse. I'd toss it out the window and use the cab/chassis/TRs for a scratch build.

[Ledvedder]

I understand the board and some components aren't looking their best. This board has been modded 3 times now. It was working fine before I decided I wanted to change it up a few weeks ago. I even gigged with it about 3 weeks ago. So I feel like there's some small thing wrong, that I'm determined to find. I just received an oscilloscope yesterday, so I'm hoping it'll be able to give me better clues.