I'd like to sell my '68 Fender Bandmaster head, but when I tested it to make sure it was in selling condition, I got a buzz that won't go away. It's fine if I turn the guitar's tone knob all the way down, but buzzes otherwise. epa thought it might be the tone knob's potentiometer, but the guitar is like new, and no matter how much i twist the knob, the buzz is consistent and increases linearly with the tone. I've tried a different outlet, I tried another (admittedly very shitty) guitar - the buzz was a little louder, but very similar.

Is this maybe just a normal thing that I should just deal with, or is there something I haven't tried? Should I just replace the tubes, as Phil suggested?

My first reaction was that you need new tubes. I think if Phil suggested it, that is probably the problem.

Now if anyone can explain why my amp picks up radio signals sometimes...

Does your guitar have single coil pickups? If so, they make noise just because of how they're designed (e.g., 60 cycle hum). The noise can get worse depending on what kind of electric fields are happening around the house. If you're near any neon lights it can get really bad.

If you're using a guitar with single coils, try using a humbucker equiped guitar and see if that cuts the noise down.

Thanks, Nez - I actually have a neon sign right outside my window (there's a shop downstairs), and I have single-coil pickups. That's very likely it. I plugged a mic into the amp, and that doesn't buzz a bit, so it's definitely down to the guitar. Maybe when I get my next amp, I'll put it on the opposite wall or in the other room.

...a couple of different cords?

fp

If you have a neon sign outside your window, short of a Faraday Cage, you're screwed.

Same frequency.