Whistle in bypass, Need help

[jrc4558]

I have a problem. My Red Fuzz and some other overdrive cirquits give a quite noticeable high pitched whisteling sound whe true bypassed. It happens only in cirquits that use IC. It disappears whe it turn the volume lknob on the pedal all the way down or reduce gain. Pedal itself is in bypass at that time. Sonic distortion and Robin's Red Fuzz are the particular cirquits. Why is it so and how to defeat it?

[The Tone God]

If these pedals are true bypassed then it could be from the input left hanging thus causing the pedal to amplifiy noise that you are hear leaking into the bypass signal. Try using the alternate true bypass wiring method that grounds the input. That may help.

Andrew

[jrc4558]

Thanx! It's just that I'm using he dpdt switch in connection with the Millenium bypass.
Is it possible to get rid of oscillation and still have LED working with only a DPDT switch?
thanx!!!

[R.G.]

Thanx! It's just that I'm using he dpdt switch in connection with the Millenium bypass.  Is it possible to get rid of oscillation and still have LED working with only a DPDT switch?

Yes, it is. You use the Millenium switching to kill the gain of the effect either at the input or inside the effect circuit.

A reasonable way to do this is with an ordinary NPN silicon transistor hooked up at a 0Vdc point shunting signal to ground. The input works fine for this.

I can (and probably should) include this in the extensions to the Mill bypass article that's been fermenting.

[jrc4558]

Mr R.G.
can you please tell me how exactly to wire the npn transistor you have mentioned. I know I'm pushing the limits of stupidity here, but I learn from experience, not from theory yet.