How to fix hum from reverb?

[octagon]

I got this on friday. It is a Peavey Artist 240(PDF)

This amp work fine and sounds great except for the reverb. The amp starts to hum as I turn up the reverb and I cant even tell if the reverb is working as the noise gets so loud.

Any suggestions or trouble shooting tips for this problem? The reverb must be solid state as it just has 4 power tubes. Anyone able to read the schematic in the pdf ?

I guess it would help if I get a footswitch for this amp because it seems that is the only way to turn the reverb on and off.

[admin]

Mitch: I am sure Greg will have some great pointers here. While we wait for him to see this post I have been down this road before. I suspect that it may be interference from the power transformer. If you can unscrew the reverb tank and move it away from the transformer while still hooked up you might be able to notice that the hum lessens the further away you go. This may provide some useful information about the fix. Unpluging the reverb cables may let you isolate it to the tank.

[octagon]

Mitch: I am sure Greg will have some great pointers here. While we wait for him to see this post I have been down this road before. I suspect that it may be interference from the power transformer. If you can unscrew the reverb tank and move it away from the transformer while still hooked up you might be able to notice that the hum lessens the further away you go. This may provide some useful information about the fix. Unpluging the reverb cables may let you isolate it to the tank.

Thanks Peter! I will try that.

[soundmasterg]

The preamp and reverb sections are solid state, and the power amp uses tubes. I don't know much about solid state and haven't messed with reverb a lot either, but generally hum from reverb is going to be caused from too much gain or possibly some caps being bad. the transistors used in the reverb section could have gone bad but thats hard to tell without troubleshooting. I'd suggest to take the amp to a tech, or if you feel like messing with it and know what you're doing, you can try to troubleshoot it yourself.

Greg

[johnallg]

If the tubes check out and you get good volume and reverb volume, then I would look at power supply capacitors in the SS stages. Electrolytic or tantalum coupling caps are also suspect.

[octagon]

Thanks guys! Well,I didn't want to mess with it so I sold the Peavey.I got a Kustom amp which I like better.

[jps]

Good move, Mitch!

[beatlefreak]

Nice looking Kustom Kombo, Mitch.

[octagon]

Thanks guys! I got a Kustom guitar to match it. Sounds so good.