ilovefuzz.com

I have no idea what to start looking for. I'll post gut shots in a minute. Basically, there is a high pitched whine when bypassed that changes pitch when I turn the knobs. I can get it to disappear but only by totally cranking the volume which renders it pretty unusable.

Sucks because it's actually a pretty cool fuzz.

I've run into that on a few of mine (and it sucks because I *know* some are out there in the universe doing just that).

The fix I have adopted is based on a 3PDT true bypass footswitch, with one of the poles dedicated to turning an LED on and off:

The LED must be fed the voltage, and the footswitch only moves a GROUND REFERENCE. Therefore, the other leg on the LED set would be unoccupied (when in bypass). To that leg I run a 100 ohm resistor from the OUTPUT of the effect (I have tried grounding the input, it did not work), so when in bypass the effect output, still oscillating, is working into a 100 ohm resistor to ground. That has quieted bleed so far, and the resistor assures I'm being easier on the output circuitry than a dead short. I can probably cough up a drawing if that would help.

Well here's what I'm looking at.


Curtis I'm the n00best of n00 with this stuff so I'm not totally sure what you mean

try a grounded input AND grounded output bypass wiring on a new footswitch. also I would maybe shorten the wires and star ground it to the input jack. I have a footswitch schematic if you need it.

No worries man! I'm having a hard time telling what's going on with that switch, but my gut is telling me the solder bridge at lower right is the bypass path, meaning the wire bent from lower left to upper mid might be the (non-functioning) silence in bypass shunt. Here's a crude drawing of what I tried to describe:



The solution to my puzzle is the wobbly green thing from fuzz output to lower right leg is my 100 ohm resistor in the place of that wire... so: if that wire is connected to the output side of the switch I'm out of ideas. However, it seems like normal people like to ground the INPUT side of a circuit, and once you're dealing with an over the top stuff the "proper" fixes become weaker. Please confirm/trace the leads on the switch. It looks like the dog-leg wire I'm speaking of is connected directly to the jack in the picture, which would be a cause in my view, (and a configuration I do not exactly understand, so I don't want to start calling it wrong - it just... doesn't look right).

eatyourguitar wrote:try a grounded input AND grounded output bypass wiring on a new footswitch. also I would maybe shorten the wires and star ground it to the input jack. I have a footswitch schematic if you need it.

Are you talking about grounding the input at PCB & output at PCB while retaining LED function and bypass on a 3PDT? I'd like a copy for reference please.

crochambeau wrote:

eatyourguitar wrote:try a grounded input AND grounded output bypass wiring on a new footswitch. also I would maybe shorten the wires and star ground it to the input jack. I have a footswitch schematic if you need it.

Are you talking about grounding the input at PCB & output at PCB while retaining LED function and bypass on a 3PDT? I'd like a copy for reference please.

scroll down to my post in this thread. it fixes these kinds of problems.
http://www.ilovefuzz.com/viewtopic.php?f=151&t=32015

although your really should have no voltage potential between ground points in an enclosure. grounds should be physically located close together with very low resistance connections (wire + solder). not everyone cleans component legs and PCB's before they start soldering. bad solder joints, oxidation, damaged wires, thin wires, etc.. should be avoided.

Ah, that's an elegant execution. Thanks for sharing!