Analogman sun face squealing

[pete_g]

It squeals when not using a buffered pedal in front of it but quietens down when the fuzz is backed off a touch. Sounds like a shielding / ground problem but I've checked it over a lot of times. I know it's not the bc108 transistors as I changed one that when I touch squeals but it did the same thing.
What's the most common cause?
It's ok when I have a boss pedal before it.

[JerS]

Sounds like you may be describing the notorious SI FF oscillation. A simple fix is to put a small (100-200pf) cap from B to C on Q1. It has always worked for me.

Let us know how it goes.

[Gus]

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Wires that are to long
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is it in a metal case?
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Grounding
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