Polytone Picks Up Radio Signals?!?

[msr13]

I picked up an early 80s Polytone Minibrute II and when on, you can hear voices, music, etc. Not loud, just under the hum of the amp. I am assuming it isn't the voices in my head, and is indeed a radio signal. Weird? How do I stop it-- the radio signal coming thru the amp, not the voices in my head?

Also, it is a pretty loud hum. That's from the circuit, right? Not the speaker. Can it be reduced or eliminated? Thanks.

[bborzell]

Originally Posted by msr13

I picked up an early 80s Polytone Minibrute II and when on, you can hear voices, music, etc. Not loud, just under the hum of the amp. I am assuming it isn't the voices in my head, and is indeed a radio signal. Weird? How do I stop it-- the radio signal coming thru the amp, not the voices in my head?

Also, it is a pretty loud hum. That's from the circuit, right? Not the speaker. Can it be reduced or eliminated? Thanks.

Sounds like a grounding issue. Is there a polarity switch? Is the outlet appropriately grounded? Does the radio signal (AM perhaps?) occur only when the guitar is plugged in? If so, try unplugging guitar and see if the cable still allows the radio signal to pass. If still yes, try unplugging the cable.

The hum might be due to any number of issues. I would get it to a good SS tech to get the connections checked out/cleaned up.

[msr13]

Thanks. It does only happen when the guitar is plugged into it. I will take it to a tech. Thanks for the guidance.

A little further google searching indicates this is not a rare problem. Surprised me, though. Again, thanks for the response.

[Archtop Bill]

Originally Posted by msr13

I picked up an early 80s Polytone Minibrute II and when on, you can hear voices, music, etc. Not loud, just under the hum of the amp. I am assuming it isn't the voices in my head, and is indeed a radio signal. Weird? How do I stop it-- the radio signal coming thru the amp, not the voices in my head?

Also, it is a pretty loud hum. That's from the circuit, right? Not the speaker. Can it be reduced or eliminated? Thanks.

What quality cable do you have? I used a cheap cable on my Spider III and often picked up radio signals. Using the same cheap cable with my Fender Frontman 212R would often generate noise as well. A higher quality cable solved both circumstances.

[msr13]

Thanks. Good suggestion. I use Whirlwind cords made from Rochester, NY. Seem indestructible and of good quality. Have used them for years and have no problems with other amps.

[merritt stone]

I once had a Marshall MG and one night it picked up some Spanish radio station.