Marshall AVT 150head no power

Lightning storm, turned all equipment off and now amplifier will not power back on. I am thinking possibly a fuse. I do not want to mess with anything inside until advised from someone who has seen this before. I have tried other power cables as well, that does not seem to be the problem. I am hoping this is something I can resolve with my own hands, so I learn something in the process. Thank you for your help.

criv001 Sep 02, 2007

Problem solved, just a blown fuse. Problem solved, just a blown fuse.
sdrayer Feb 19, 2009

My Marshall AVT150 keeps blowing the TDA7293 chip after i replace it, but i can't find a short anywhere else in the amp that would make it short out. what are some things that could make these chips short out?

2 Answers

Anonymous

Most of the problems with the AVT 150 amp blowing fuses have to do with the TDA7293 power amplifier IC being shorted. If you have good solder skills this and a new fuse will probably take care of the problem. If you do not have good mechinical / solder skills, take it to a Marshall authorized repair station.

Posted on Nov 13, 2007

Larry Stiles

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301 Answers

I would go ahead and take it apart, after you unplug it or course. if there is fuse on the back there will be one just off the ac line inside. These amps have an 12ax7 tube in them I beleive ,and large filter capacitors in them where voltage could be stored for a time after you unplug it ,but this is a fairly modern amp with bleeder resistors so it will be safe . you can wait over night to be safe, anyway you won't go touching the large capacitors anyway you are just changing a fuse. look for something like 2 amp or 5 amp in value. replace it with the same value.

Posted on Sep 18, 2007

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