Amp is picking up radio signal

That's usually a sign that your instrument cable isn't shielded. Try a different cable and see what happens.

Try running the amp through a power bar that does line filtering. My guitar player once had this problem and that cured it.

Other than that the signal could be coming into the front end of your amp. A bit of corrosion or a failing solder joint could be providing the rectification and making the result audible.

Paul

Does your amp pick up the radio signal without anything (instrument cables) plugged into it?

I used a small Marshall guitar amp plugged straight into a condo wall outlet and could hear a Chinese tv station super clear.

If you prove it's your cable picking up the signal (and chances are it is), then you can buy an RF Choke for a couple of bux at Radioshack, fits around your cable next to the input jack and will filter out the RF. The amp *should* have effective RF filtering built into the input section, but not all do (see threads on early GK MB2-500 heads).

If a different instrument cable doesn't help, it could be a bad input jack on the amp.

Also try a different bass; could be something faulty in your bass.

As others have said, this is often caused by a problem with your instrument cable. Try another cable. Sometimes it goes away if you change the direction that your amp is facing. Also, make sure that your cable is lying flat on the floor with no loops in it. Make sure that the nut on your input jack is tight. It could also be caused by a bad ground connection inside the amp at the jack.

If all else fails, you might be able to fix it by isolating the input jack from the chassis (there are washers available to do this), then installing a small capacitor (10 nanofarads) from the jack ground to chassis. I would speak to the manufacturer before you started getting into measures like this.

...and if you have any large transmitters nearby, your out of luck.

deekay911 said:

The amp *should* have effective RF filtering built into the input section, but not all do (see threads on early GK MB2-500 heads).

Click to expand...

Should is the key word here. After living next door to a radio station, sometimes you just have to live with it.

However if you live near a radio station and the broadcast is coming through other devices, such as telephones, tv, answering machine, etc, contact the FCC and file complaint against the radio station. The FCC is very strict on it's rules regarding a broadcasting station and the interference it gives off. My numerous complaints eventually got the offending station to remedy the problem, but it took a few weeks.

Hopefully it's just a crappy cord and not the front end of the amp picking it up.