Marshall Mosfet 100 Problem

ThePrettyDamned

HHwarner said:

Thanks once again for your help. Much appreciated. Iv a lot to learn but willing to try

How easy/hard are you finding it to work on?  I'd love to get one of these amps someday

HHwarner

These older amps are pretty easy to work on. Iv got 2 JCM 800s which I do my own work on too when I can. Wouldn't want to try on modern stuff at the moment though all too small. My soldering skills not good enough ha ha

HHwarner

Well after replacing the offending diodes, transistors and resistors, the amp lasted about an hour and blew again. Exactly the same thing. One transistor blown and burned resistors. Its actually burned the tracks from the board. Whats the best way to repair that? Bridge over the one end of the resistor with the burned out tracks with a piece of wire to the next point on the board?

ICBM

Yes, but don't do it until you've worked out why it's doing that.

I'll have another look at the schematic and see if I have any ideas!

HHwarner

Cheers John