Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Heavychills on August 27, 2017, 03:07:32 am
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I bought a Peavey butcher off of Craigslist last week that was turning on but not making sound. I got it home and immediately tested all the tubes. All the tubes we're working fine. So I opened the amp up only to find the entire thing had been gutted out and rebuilt. Judging by the Meecury Magnetic's transformers and choke that were installed this was some sort of personal build Similiar to a 100w Marshall plexi. So I'm trouble shooting around the amp trying to figure what could possibly be wrong and I notice the OT CT and one of the choke wires are disconnected. I also noticed the B+ fuse is grounded but has nothing else connected to it. So I tried connecting the OT CT and the choke to the B+ fuse but no sound still. I've got some other ideas I'm going to try but I'd like to hear some advice on how to trouble shoot this. Sorry my picture files seem to be to large to attach.
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Draw a schematic.
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Agree with Sluckey, draw a schematic for us to see, please. Look at the Marshall schematics as a starting point since you seem to think this may be a Marshallish type rebuild?
http://el34world.com/charts/Schematics/files/marshall/Marshall_1987%20JMP%20Lead%2050watt%20EL34.gif (http://el34world.com/charts/Schematics/files/marshall/Marshall_1987%20JMP%20Lead%2050watt%20EL34.gif)
http://el34world.com/charts/Schematics/files/marshall/Marshall_50w_2204s.pdf (http://el34world.com/charts/Schematics/files/marshall/Marshall_50w_2204s.pdf)
http://el34world.com/charts/Schematics/files/marshall/Marshall_jtm45-readable.pdf (http://el34world.com/charts/Schematics/files/marshall/Marshall_jtm45-readable.pdf)
http://el34world.com/charts/Schematics/files/marshall/Marshall_Schematics.htm (http://el34world.com/charts/Schematics/files/marshall/Marshall_Schematics.htm)
IF you have Windows PAINT, you can open your pictures up and then "resize" them to get them within the proper size for posting. You simply "resize" them to maybe 45% horizontally and 45% vertically and resave them.
Then click on the saved photo to see what size it is now. We can be more helpful to you if we have a schematic and photos to work with.
IF you got the amp at a good price and it has Mercury Magnetics transformers in it and you can get it working well .......... you may end up with a remarkably good buy?
With respect, Tubenit