Screaming Muff

[Radamus]

I recently completed a Meatball clone and I've been having a lot of fun with that, but I thought I'd try working the big muff (triangle, I think) into the effects loop. The result is quite a bit of a volume drop, and there is a high pitched tone that comes through rather strongly. I took the audio probe to the muff (which makes the sound whenever the 3pdt is set to on, even when only plugged into itself) and I got the shrieking sound everywhere. Not much of a place to start. The muff has no IC's in it, so nothing's oscillating to my knowledge. Any reason why it would scream?

• It only screams when not in bypass
• It had worked just fine earlier on its own, now it doesn't
• No IC's
• I don't know where to start

Usually, I would use the audio probe to find the place that is having a problem. Unfortunately, it whistles everywhere.

Any help would be great. Thanks.

[R.G.]

Go read "What to do when it doesn't work".

[Barcode80]

and FYI, IC's being in the circuit has no bearing on whether you get oscillation or not. oscillation amounts to a signal constantly overlapping itself, which will happen any time you attach an output back to the input.

[Radamus]

I thought about it a bit more and I think that I forgot to ground the send/receive jacks. I don't know why I thought switching jacks were any different.