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Apologies if this topic has already been beaten to death, but I'm new to BYOC.

I have the 5 knob compressor with all jacks on top. Seems to function as expected but it is picking up a radio station very clearly. I know it's the comp because it is the only change to my previoulsy radio-free pedal board. Picks it up at numerous power sources, as well as battery, 9v and 18v adapter. I've search through the forum and have found mention of this problem, but I can't find out what the solution is or guidance as to where to start looking. Any help would be greatly appreciated. I'm hoping to break out the comp at band rehearsal on Sunday. Rock on brothers! (and sisters!)

Not sure about the fix...
Is it a good station at least?

Thanks Cap'n - funny, but not helpful.
Additional information: when I touch the lug on the trimpot with my thumb, the radio i/f goes away... I'll check the solder joints and reflow. I'll post if this is the cure.

if that doesn't work, you might consider adding a ferrite bead around the input wire, or using shielded wire for in/out. others here can advise better than I, though.

I have personally never had any RFI issues with any of the comp pedals I have built but I did have trouble with a fuzz pedal once. Placing a small cap (47pf or so) between the input and the ground can eliminate the interference.

You might want to do a search for radio interference. You can probably find a fix on here somewhere.

Thanks coolhand. When you say place the small cap between the input and ground, do you mean connect the cap to the IN and Ground lugs on the in jack?
I did a search on radio interfernece and the results are this message string....

here's a recent thread:
viewtopic.php?f=9&t=29051&hilit=radio

Yep exactly. The best way to do it with the newer 5-knob version. If 47pf doesn't completely work, you can try increasing to 100pf or even 220pf, just be conscience of any changes in sound of the pedal.

I made this for someone a while back:

Thanks for the pic DC.

I like to use pics to explain stuff. Usually cuts the confusion level in half.

Thanks for all the helpful information.
I noticed that my input wires were pretty long @ 4" or so. I'm starting with replacing them with shielded wire. If that doesn't remove the RIF, I'll put the cap in. Since I am digging into it, I decided now is a good time to paint the enclosure. I got the dark green Hammerite hammered-finish rattle can from Home Depot. (already have plenty of black pedals!). Wating for it to dry before I re-install the jacks. It's going to look good. I'll post my results soon.

Well, unfortunately using shielded wire and the 47pf cap did not solve the radio interference problem I'm having with my v2.1 5 knob compressor. The pedal works fine, except for the RIF. Turning any of the knobs does not seem to affect the amount of interference.... BUT, the sustain knob is a bit sketchy, though, in that it seems to work fin up to 95% clockwise rotation, the fuzzes out. At 100% clockwise, it is quiet until I strum a note - then fuzzes out hard, attenuating the note within a second or two. I can't hear the radio when that happens. I am a working musician, so I can't use the pedal as it is now. Any more ideas on how to fix this? Or am I screwed and this is now a candidate for multi-mods?.... Thanks in advance for any additional help with this. Stan

Have you read the tips on how to set the trim pot to eliminate distortion? It's in the build docs.

yes. I turned the trimpot counter clockwise a tiny bit and that corrected the fuzz-out issue. Still a noisy circuit with radio interference though....

OK, this is a weird question, but one I have to ask: when testing the pedal, did you do it with the enclosure lid on? and did having the lid on (i.e. having the pedal fully shielded) make a difference in the rfi? I know my circuits are a lot noisier on the breadboard than they are in enclosures...

Not a weird question, because I tested it both ways w/o any difference. I've taken the back off this thing 100 times by now I put a 100pf cap across the IN and ground lugs on the input jack. No diffference. Something in the circuit is picking up the RF, but I don't know enough about circuits to know which components would be most susceptable to it, if any of them would be.

OK. I don't want to give up on this just yet! Like I said, the pedal seems to be working as advertised (with the exception of the noise) and I can hear why people like this compressor circuit so much (although a little more of the natural bass would be nice)

Bear with me and please chime in with any knowledge you all have around this. The more research I do about RIF, the more confused I am getting. Here are some questions for those that know more about this than I:

Can something within the pedal actually pick up radio signals, or is the pedal simply amplifying a radio signal that is always present but usually filtered out?

If yes to the first part, which components would be 'receiving' the radio signal - I can target them for test or replacement.

If yes to the second part, which components are there to filter the RIF out?

If yes to both, I am still screwed and I will have learned an expensive lesson about building my own pedals.....

UPDATE: I tried the ferrite chokes (the Radio Shack $2.99 clip-on's) on the IN and OUT wires; No noticable reduction in the radio station interference.

Not sure what my next step should be. Any suggestions?
Stan

Can you post pictures? There is no one component that eases RF. Maybe your layout promotes something or something is touching something it shouldn't (sorry for that muddled sentence )
Pictures may help.

I will as soon as I can.
I've done additional research that leads me to believe a poor solder connection could cause this as well. I'll probably need to clean and reflow all solder connections, 1 by 1, until I (hopefully) locate the problem. I was hoping that there is a 'mostly likely suspect' component that I should start with. The challenge is that the pedal works!

In your experience, where are the most common solder problems on the rev 2.1 5 knob comp build? I could start with those if there are any....

Stan

I think the most common solder problems on most builds are with the stomp switch.

Does the blend knob have any effect on the RIF?

I ask that because it could help to possibly find the source of the interference.

I plan to work on it tonight. I'm going to rework the stomp switch assembly (remove and resolder all points), and test the blend knob effect on RIF. Will report back. Thank you very much for the reply!

Turning the ratio knob all the way counter clockwise (no compressed signal) did remove the RIF. I reflowed the stomp switch solders and now there is a POP when engaging and disengaging the pedal, that wasn't there before. I checked the ground wires and reflowed all of them. I seem to be making it worse at this point. I'm bummed because I liked the tone when it was working right. Turning the trimpot affected the volume of the radio signal - all the way in either direction and it was gone, turning it to 12 o'clock and radio got louder (it was a basketball game. Almost ready to cut my losses on this baby..... thanks for the suggestions anyway. Stan

UPDATE- I gave the pedal to the budding rockstar down the street and bought a Keeley 4-knob compressor. Lesson learned.......

Sorry to hear it didn't work out. Building is not for everyone. Hope to see you around soon.