Radio Pickup on a Black Ash Clone?

[Fingolfen]

I've gotten a question from someone with one of my Black Ash clones and they're getting radio pickup. I've done some reading and it seems like the signal could be entering from a variety of sources, including the guitar, cable, etc. Any thoughts to help him troubleshoot and if it does turn out to be entering at the pedal, thoughts on how to rectify?

 

[jimilee]

I've gotten a question from someone with one of my Black Ash clones and they're getting radio pickup. I've done some reading and it seems like the signal could be entering from a variety of sources, including the guitar, cable, etc. Any thoughts to help him troubleshoot and if it does turn out to be entering at the pedal, thoughts on how to rectify?

How’s the wiring in his casa, pretty old or poorly grounded?

 

[Locrian99]

I have no help but my very first pedal attempt I bought one of those Craig Anderton books back in the mid 90’s I was like 15. Built one of the distortion pedals. All I could get it to do was pick up a local Mexican radio station out of Woodburn Oregon. I recently had an issue with a breadboarding ruby using a lm386 that also was picking up a similar type of radio station (I’ve moved about 3 miles from where I lived before lol, have to wonder if it was the same one). Anyways, it was a layout issue with the gain pot wire running parallel to the input wire. This was on a breadboard though.

 

[cliffs_trip]

I’m not so sure it would be the pedal in particular. The other day I was playing through a high gain pedal and heard an Asian lady preaching. Bypass pedal, no preaching. Next day a couple of guys talking about religion, bypass the pedal, suddenly I lost my religion

It just makes what is already there more apparent for my situation.

 

[jimilee]

I played a show in Dalton Ga many years ago. We had the local football game coming through our monitors until it was over. Blew a monitor speaker that night, too. Good times.

 

[jwin615]

Buddy had a big brick Dano fan tone in HS that picked up AM really well.
Used to listen to Art Bell through his Laney with it
It can absolutely be a grounding issue.

 

[jesuscrisp]

Usually an issue if there's a grounding issue, e.g. the enclosure is not grounded.

 

[music6000]

I can get radio stations on just about every pedal I have built when it is not in the enclosure if I touch components.
Either the pedal isn't grounded to the enclosure properly (powdercoat) or Input & Output wires may need need moving.

 

[KR Sound]

Used to listen to Art Bell

Haven’t listened to Coast to Coast in ages. Is it still on?

 

[jwin615]

Haven’t listened to Coast to Coast in ages. Is it still on?

Art passed 5 years ago. It's still on. I think there is a rotation of hosts now.

 

[Fingolfen]

Thanks all - I'm fastidious about making sure everything is grounded, but something could have come loose on this one. I'll also check the I/O wires.

If it's not either of those, anyone have a Plan C????

 

[swelchy]

Thanks all - I'm fastidious about making sure everything is grounded, but something could have come loose on this one. I'll also check the I/O wires.

If it's not either of those, anyone have a Plan C????

Tin foil hat while playing?

 

[jwin615]

Thanks all - I'm fastidious about making sure everything is grounded, but something could have come loose on this one. I'll also check the I/O wires.

If it's not either of those, anyone have a Plan C????

Faraday cage.
Make sure there's good metal on metal contact on the shell/enclosure, make sure the enclosure is grounded(no paint/powder over spray insulating)and the bottom is snug. Long cracks are worse for RF leakage than holes.

 

[Fingolfen]

I always make sure I have the full Faraday cage going. I'm going to swap him one I've verified the jacks and enclosure are all grounded to each other. I'm guessing the pedal is amplifying a signal coming in from elsewhere in the chain, but I'll re-check his once I have it back in hand.

 

[jwin615]

Try a bypass cap of 20pf to 200pf cap across R2. Start closer to 20pf with whatever you have on hand. That should give at least some of the RF an easy path to ground.

Wonder if others have this issue with this build? May be worth scaling the resistors down, if so.

 

[dcfvgb]

Loose jacks?

 

[Coda]

I listened to a few innings of a Phillies game last summer through a breadboarded Ge Fuzz-Rite…

 

[cdwillis]

I've picked up radio signals while messing with tonebender and fuzz face circuits on my breadboards. Usually it's when the fuzz is cranked, but my guitar volume is turned down. My solution has been to put a small cap, like 50pf or maybe 100pf, on the circuit input to ground. I'm not sure if that would be a great long term solution for something that's already boxed.

 

[jwin615]

I've picked up radio signals while messing with tonebender and fuzz face circuits on my breadboards. Usually it's when the fuzz is cranked, but my guitar volume is turned down. My solution has been to put a small cap, like 50pf or maybe 100pf, on the circuit input to ground. I'm not sure if that would be a great long term solution for something that's already boxed.

Same.qs I said post 15. Need to bleed off the RF to ground
Altering the first voltage divider resistors to 1/10th value can help as well if a cap doesn't clear it.