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Marshall MF350 troubleshooting


I have a Marshall MF350. I'm pretty sure that one side of the 12AX7 tube is gone bad (I checked it with a tube-tester) and so did all 4 TDA7293 power ICs (some have shortened, some have 46 ohm between V+ and V-).
When I turn it on the fuse blows immediately, and when I disconnect the 4 power ICs and the circuit board with both tubes (1x 12AT7 and 1x 12AX7) It doesn't blow.
Any suggestion for anything else to check before I get it to work again?
July 21, 2012 @02:03pm

This is one to take to a pro repairman.
July 21, 2012 @11:34pm

Well, yeah, I kind of fit this description.
Anyone else wanna give it a try?
July 22, 2012 @03:42pm