Picking up Radio Signal with my Sunface BC108

[ChaseTheAce]

So I recently picked up an Analogman BC108 Sunface (Silicon) fuzz pedal. When I run it through my AD30 in my closet and Fender Super Champ XD in my room, I pick up loud and obnoxious radio or television sounds in the background noise of my amp. All of my other fuzzes (none of which are Silicon) don't have the same problem.

I'm currently living on the second floor of an apartment, so I'm not sure if the close quarter surroundings have anything to do with the interference.

Anybody else had a similar problem? Anybody have a solution?

I have yet to try the pedal outside of my apartment, so that will be next on my to do list

 

[SCREAMIN SETH]

Could be bad grounding or long wires in the pedal. When you turn down the fuzz gain, does it go away? Also, if you turn your guitar or pedal at different angles that can lower the radio a lot.

To try to fix grounding, touch one end of a wire to metal on the fuzz and them to the metal case of a cable jack. If you are running a battery, try twisting the battery wires around each other to make smaller loops.

The problem is that fuzzes have a ton of gain and wires That are a couple of inches make good antennas...

 

[wingwalker]

Fuzz Faces are bad about that (most fuzz pedals are) but the higher the gain the stronger the the station will be...and the BC108 Sunface is pretty high gain!

 

[whiskerBox]

I also have a sunface bc108 and live on a second floor apartment lol. No radio signals here ,but I would suggest trying a 9v battery instead of a power supply and see if that helps as well.

 

[analogmike]

Radio Frequency Interference (RF IF) is a tough one, most gain pedals like Fuzzes and even some wahs have a lot of RF problems.

Since we cannot duplicate the problem in our shop (it had no noise here) it's not something we can easily fix at our shop.

Gain is amplifying the RF from the air like a radio, it is tuned to the local station. Sometimes shortening wires or adding ferrite beads will help but since we don't have the problem here we would only be guessing. If you have a good tech he can try shortening the internal wires one by one and test to see if that helps, or he can try adding more and more ferrite beads and see if that stops the noise.

Also you can try to add a small capacitor on the input of the board or the input jack to ground, that often kills the noise. Try something small like 100pF then go bigger up to .01uF if needed. We often put a small cap right on the switch from the TO BOARD wire connection (gets connected to input jack when ON) to the GROUND connection.

Adding a capacitor on the Beano Boost will often help. We use a 221 (220pF) disk cap, from the output of the transistor to ground. The output leg is the one that goes to one of the volume pot lugs. It's usually a white wire. Tack a cap from there to ground (the body of the volume pot is a good ground).

.
Also dirty jacks can cause RF interference, try cleaning them with a swab and some contact cleaner.

A customer wrote :
"One thing I did was to uncoil all the power leads in the back of the rack. I had them coiled up pretty tight and then cable tied. This immediately helped, but I wasn't completely satisfied.

At this point, I noticed that to make the radio signal be it's worst, touching the audio plugs on the back of the power amp (Metal sleeves) would do it. So next I soldered some 4.7pf capacitors across the DC connectors on my pedals. "

another customer with RF problems with a sunface wrote:

"Thanks for the note, Mike. After applying an, ahem, no-to-low-tech technique it seems that the RF IF problem is gone. Get this: after reading your reply I got to fiddling with the guitar cables in the chain, which includes a Framptone Amp Switcher in front of two amps. Anyway, I just swung the guitar-out cable from the Strat around from the front and behind my body and presto/change-o, the RF IF disappeared. No contact cleaner, no screwdriver, no solder. No BS."

Here is another who found a simple fix for RF noise on a sunface:

"Thanks for your detailed response to my question. I was able to solve
the problem. I got a ferrite clamp from Radio Shack and tried clipping it onto my guitar cable. It eliminated some of the RF noise, but not all of it. I also noticed some loss of clarity from my guitar signal so I decided to ditch the ferrite and try adjusting the internal trim pot. I set my guitar volume to the most offending spot and adjusted the trimmer until the noise went away. I only ended up turning it down a bit. I would guess it's somewhere around 85%. Now I can use my guitar's volume knob to get that sweet spot w/o the RF interference."

The "CLEAN trimpot on the Sunface is an excellent way to reduce noise, just try adjusting it a hair.

Another customer fixed his wah by removing the in and out jacks and sanding down the inside of the pedal to bare metal for better grounding contact. Then he tightened down the jacks well and the RF noise was gone. I fixed a HUMMING wah by making sure the bottom plate was FLAT and tight. The wah plate may help with that.

Hope that helps, good luck!

 

[WesWagner]

Put visual sound pedal somewhere in the chain, should fix it.

 

[sixty2strat]

lived in downtown philly in a loft got awful Rf, even with out a fuzz , straight into the amp I could be playing a zep riff and the same tune was on WMMR. moved to the burds and not a problem....of course life is dull as **** but no RF

 

[stratguy23]

I got RF interference with my Dallas Arbiter Fuzz Face with BC108Cs when I lived in an apartment, I think it is just something you have to deal with sadly if you are in close quarters...

 

[kirkham13]

I have a sunlion sunface with nk 275's and beano boost, the beano picks up frequencies, as can the sunface, as do other pedals, as can my nos preamp tubes, but its always intermittent, and I just turn the effect down or tweak it and it goes away. I don't think I will bother customizing the pedal, I think its part of that type of circuit and I just work with it.... its part of what makes a fuzz so fuzzy........

 

[timhulio]

If you put a buffer in front (I think this is what the guy who suggested use the Visual Sound pedal was getting at) you'll kill the RF interference. Unfortunately your Fuzz Face will no longer sound any good.

I've just moved to an area with exceptional RF interference. The repeater for Capital Gold (oldies station) for the whole of London is less than a mile north of me. So stuff like FFs, Superfuzz, Os Mutantes and likely most old fuzz circuits with BJTs pick up radio like nobodies business.

Try whatever Analogmike suggested. I like to use a 1k resistor in series at the input, followed by 100pf-470pf cap to ground. Keep this as low as possible or you'll lose treble.

 

[ChaseTheAce]

Radio Frequency Interference (RF IF) is a tough one, most gain pedals like Fuzzes and even some wahs have a lot of RF problems.

Since we cannot duplicate the problem in our shop (it had no noise here) it's not something we can easily fix at our shop.

Gain is amplifying the RF from the air like a radio, it is tuned to the local station. Sometimes shortening wires or adding ferrite beads will help but since we don't have the problem here we would only be guessing. If you have a good tech he can try shortening the internal wires one by one and test to see if that helps, or he can try adding more and more ferrite beads and see if that stops the noise.

Also you can try to add a small capacitor on the input of the board or the input jack to ground, that often kills the noise. Try something small like 100pF then go bigger up to .01uF if needed. We often put a small cap right on the switch from the TO BOARD wire connection (gets connected to input jack when ON) to the GROUND connection.

Adding a capacitor on the Beano Boost will often help. We use a 221 (220pF) disk cap, from the output of the transistor to ground. The output leg is the one that goes to one of the volume pot lugs. It's usually a white wire. Tack a cap from there to ground (the body of the volume pot is a good ground).

.
Also dirty jacks can cause RF interference, try cleaning them with a swab and some contact cleaner.

A customer wrote :
"One thing I did was to uncoil all the power leads in the back of the rack. I had them coiled up pretty tight and then cable tied. This immediately helped, but I wasn't completely satisfied.

At this point, I noticed that to make the radio signal be it's worst, touching the audio plugs on the back of the power amp (Metal sleeves) would do it. So next I soldered some 4.7pf capacitors across the DC connectors on my pedals. "

another customer with RF problems with a sunface wrote:

"Thanks for the note, Mike. After applying an, ahem, no-to-low-tech technique it seems that the RF IF problem is gone. Get this: after reading your reply I got to fiddling with the guitar cables in the chain, which includes a Framptone Amp Switcher in front of two amps. Anyway, I just swung the guitar-out cable from the Strat around from the front and behind my body and presto/change-o, the RF IF disappeared. No contact cleaner, no screwdriver, no solder. No BS."

Here is another who found a simple fix for RF noise on a sunface:

"Thanks for your detailed response to my question. I was able to solve
the problem. I got a ferrite clamp from Radio Shack and tried clipping it onto my guitar cable. It eliminated some of the RF noise, but not all of it. I also noticed some loss of clarity from my guitar signal so I decided to ditch the ferrite and try adjusting the internal trim pot. I set my guitar volume to the most offending spot and adjusted the trimmer until the noise went away. I only ended up turning it down a bit. I would guess it's somewhere around 85%. Now I can use my guitar's volume knob to get that sweet spot w/o the RF interference."

The "CLEAN trimpot on the Sunface is an excellent way to reduce noise, just try adjusting it a hair.

Another customer fixed his wah by removing the in and out jacks and sanding down the inside of the pedal to bare metal for better grounding contact. Then he tightened down the jacks well and the RF noise was gone. I fixed a HUMMING wah by making sure the bottom plate was FLAT and tight. The wah plate may help with that.

Hope that helps, good luck!

now that's customer service at its finest. thanks a lot Mike!

I have absolutely zero pedal modding, circuitry experience, so I am hesitant to attempt any serious fixes. i will try some of the easier solutions you suggested first and see if that helps.

thanks to everyone else who responded as well. i will give all of these suggestions a try when i get the chance