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Marshall 8080 valvestate amplifier

Ive got a marshall 8080 valvestate guitar amp, but everytime i put a fuse in and turn the power on it blows the fuse. all the valves have been changed and this didnt solve the problem. would be great if someone could help me out

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There could be a short in the rectifier diodes or in the transformer itself. Can you take some measurements inside the unit?

Let me know.
Dan

Posted on May 29, 2008

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I have fixed so many of these amps over the years... Marshall Valvestate series of amps are notorious for dry solder joints developing on the main PCB. If you have the skills(or an old mate that does)Remove the PCB from the chassis and resolder any suspect dry joints and you will fix the problem. Check particularly about any components there the PB has changed colour. This is an indication of heat in that area, and heating and cooling is a major cause dry joints.
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