Please help. Hearing radio transmissions through my mark V

This just recently started to happen. Before, it was not a problem at all. Now I am hearing radio chatter through the amp. If I tap the side of the amp firmly with my hand, it stops. But then starts again after I play through it, which makes me think it's due to something being loose. Any help would be greatly appreciated. Thanks.

I have gotten them too...

Not sure if it's just the amp. Could be one of my effects pedals or the guitar picking it up.
I've had it happen before on other amps as well. I just feel sorry for what the
guy on the other end is getting....haha..

tptb73 said:

This just recently started to happen. Before, it was not a problem at all. Now I am hearing radio chatter through the amp. If I tap the side of the amp firmly with my hand, it stops. But then starts again after I play through it, which makes me think it's due to something being loose. Any help would be greatly appreciated. Thanks.

Click to expand...

Try changing cables before messing around with tubes. Everytime it has happened to me, a cable in the signal path has let me down. Get the best quality shielding you can afford, and see if it fixes the problem. Even "good" cables can fail and let in unwanted radio interference ..

Good luck!

some folks will solder a small cap (.001uf) across the lugs on the input jack to reduce rF interference...

Thanks for the replies, everyone. I will try the cables first.

It happened in my old building...now I don't have problems. Same cables.

Just move it around and it should go away

Mesa amps don't have an input grid resistor to prevent radio signal to reach the input tube. The guitar cable act like an antenna, and the grid input resistor create a low-pass filter in conjunction with the input tube.
With a small resistor, say 10k to 68k, the guitar signal wouldn't be altered but the radio frequencies would be cut.
I always wonder why Mesa never add that to their design.

http://www.regiscoyne.com/tech/68kinput/

jb's 52 said:

I have gotten them too...

Not sure if it's just the amp. Could be one of my effects pedals or the guitar picking it up.
I've had it happen before on other amps as well. I just feel sorry for what the
guy on the other end is getting....haha..

Click to expand...

:lol: Thanks for the humor.

I had issues but was not isolated to one amp. Turns out it was cheap pups on a used guitar I bought, I planed on pup replacement so not an issue after I restored the guitar.

First the good news. It's not your amp. Welcome to your guitar becoming an AM radio antenna. Probably does not happen on the clean channel also are you using a Telecaster or Stratocaster? They seem to be more susceptible to doing musical double duty. I spoke to an Electronics Tech just today about that cute little radio trick my guitar is pulling lately. Above "Thunda1216" posted "solder a small cap (.001uf) across the lugs on the input jack to reduce rF interference" That is the exact some thing the Electronics Tech told me this morning. I mean the exact same thing. I am actually going to give it a try.

I had an old digitech whammy do this. I built a faraday cage around it and it fixed the problem. But that pedal is a tone sucker so ended up swapping it for a boss harmonist ps-6. Check your pedals and cables its prob not the amp unless you have something sitting ontop of it.
http://www.thesurvivalistblog.net/build-your-own-faraday-cage-heres-how/

OldTelecasterMan said:

First the good news. It's not your amp. Welcome to your guitar becoming an AM radio antenna. Probably does not happen on the clean channel also are you using a Telecaster or Stratocaster? They seem to be more susceptible to doing musical double duty. I spoke to an Electronics Tech just today about that cute little radio trick my guitar is pulling lately. Above "Thunda1216" posted "solder a small cap (.001uf) across the lugs on the input jack to reduce rF interference" That is the exact some thing the Electronics Tech told me this morning. I mean the exact same thing. I am actually going to give it a try.

Click to expand...

Which input jack do you put the cap across the lug? The guitar or the amp?

The impression I got was the cap. is installed in the guitar as when I explained what was going on the Tech laughed and said the guitar strings were acting as an antenna. I have yet to install one. It so far has only happened at my house and it's not very loud so I just ignore it. I have a Boogie F-30 and it does it also. It's a location thing with interference. I also have a Gibson Jazz Fusion but it never gets interference. Both my Telecasters do.

I live near an air base and I have had pilot radio transmissions cut into wireless systems also. I could hear, actually even the people at the bar could hear the pilot talking to the tower. It was good for a laugh. I dumped the wireless for a cord and never went back. This was during the 80s & 90s when I had gone to the "Dark Side" (Digital effects racks and Solid State amps)... I'm better now.

I had this issue (easily reproduced) and it was my instrument cable that caused it (spectraflex) and I replaced the cable with on that has better shielding and the problem is gone.