Marshall Lead 100 Mosfet 3210 producing loud intermittent/random noises

[mattinthebox]

I no longer have any loud pop while the amp is running, I have also cleaned up the carbon track in the volume pot & that eliminated any crackle when adjusting volume.

However there is definitely an issue within the reverb circuit.

I returned TR4 & TR5, [MPSA06 NPN] which tested good, to the circuit & reattached the red lead [return] to the circuit board for the reverb tank.

When I turned the amp back on after putting the transistors back in I now have a loud buzz which gets even louder if I touch the reverb pot.

I thought it may go away when the reverb tank was plugged in but when I plugged the rca leads into the tank there's no change.

[thomasplooij]

Hey! I hope you can help me with my marshall 100 lead mosfett amp. I have i few issues... 1. there are some serious burn marks under resistor R46 and R47. Both of them are 330 ohms which is weird because on the diagram i see they should be 270 ohms. There are resistors on the places of capacitors which i dont understand either. Aaand last of all there are caps underneath the pcb!! Can you please help me out??

[g1]

Don't worry about things not matching the diagram, there were factory changes and the diagrams are often not a perfect match.
Everything you have described sounds like it may be normal for this model. Those resistors run very hot. They may need resoldering, but they should be fine.
Are you having some problem with your amp?