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Marshall SS hum......no sound

3/27/2003 5:35 AM
Ralph	Marshall SS hum......no sound You know the problem. It's the typical shorted output transistor sound. Loud low frequency hum, no sound at all from guitar. But i cannot find any problems with the outputs as far as shorts or open conditions. This is a 1980something Marshall solid stater. I have checked every component in the thing. However, i am by no means a tech, and checking semiconductors for me is an exercize in looking for open or shorted components. All diodes, electrolitics, and transistors seem to read ok as far as shorts or open conditions, and all IC's are socket mounted, so i swapped them out with known good ones. I also checked all resistors and they're fine. What would your best guess be? This is a small SS 1-10" combo. Thanks in advance.

3/27/2003 5:35 AM

Ralph

Marshall SS hum......no sound

You know the problem. It's the typical shorted output transistor sound. Loud low frequency hum, no sound at all from guitar. But i cannot find any problems with the outputs as far as shorts or open conditions. This is a 1980something Marshall solid stater. I have checked every component in the thing. However, i am by no means a tech, and checking semiconductors for me is an exercize in looking for open or shorted components. All diodes, electrolitics, and transistors seem to read ok as far as shorts or open conditions, and all IC's are socket mounted, so i swapped them out with known good ones. I also checked all resistors and they're fine.

What would your best guess be? This is a small SS 1-10" combo. Thanks in advance.

Replies:

Enzo OK, you have a loud hum coming from... -- 3/27/2003 10:09 AM
Dale this has become very wierd... -- 4/12/2003 6:00 AM
Dale CORRECTION !!!...i measured wrong -- 4/14/2003 4:27 AM