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Yes, I might try and change the ground lug wiring though as the layout is confusing on these jacks, they're different from all the diagrams/images I've found

Hi Midwayfair, I've seen a few posts you've made before about FF's and they were very helpful, so thanks for that because they were all things I considered when making/testing this one.

I've heard all nightmare stories about oscillation on breadboard so that's why I've perfboarded this one after it oscillated on breadboard, just to eliminate the fact it could've been caused from building on breadboard. I eliminated a few other factors like using mains and basically everything I can think of. I did have a potentiometer on the bias and even at 4.5 it was making the same noise. I've made this circuit on breadboard multiple times with the same result, even with the bias right (this was a while ago). It seems I get oscillation no matter what circuit I build, even when I've built gated type fuzzes they still have some oscillation going on in the background. I double checked the pinout, its all correct. One transistor won't oscillate on its own, but two will.

Yes, if you listen to the sample, you'll hear me roll my volume down at about 0:14, and then soon after fiddle the fuzz pot. I double, infact, triple checked the resistors when I was breadboarding it, and even fiddled with a couple values like the feedback resistor. I'll either get little to no gain/fuzz or I'll get oscillation. I've tried caps between both q1's and q2's collectors and bases, at the same time too, they just cut some high end off, but not the oscillation.

I've ordered some new transistors which should be here in 2-3 days, AC128K's (dont know the hfe, woops), and some BC108's with a 10nf cap that I KNOW will take the voltage of the circuit (100V cap), whereas these ceramic caps were very tiny and I don't know if they could take the voltage, but then wouldn't it just not pass signal through? Something that might be interesting is when I've swapped the output cap to 100nf and the oscillation got deeper, but I know that the capacitor was 63V. If there's anything I can try before the new parts come I'll try it! But if I get the same problem, obviously there's something very wrong. Can wiring jacks up wrong cause this? I have stereo jacks, but not like any I've seen anywhere else, they pass signal through consistently though.

Thanks for the replies!

I think its bad transistors, I got all of mine from the same supplier in china on ebay, so maybe thats why they all oscillate... I am powering it with a battery at the minute just to eliminate the fact there could be mains hum. I know I've wired right because its making exactly the same sound on perfboard as it did on breadboard! The things currently connected to ground --

In/Out jacks (ground lug)
Q1 Emitter
Bypass cap
Negative battery
1st lug of potentiometer (3rd lug connected to Q2)

So, I have followed the Fuzz Face Silicon Circuit, and compared it to a few others, like Madbeans Hipster pedal and the like. Heres the one I used...


I started this on breadboard with 2n4401s, but I had tried 2n2222s and have now swapped to 2n5088s, with no noticeable difference..
I have now soldered this on perfboard, but I'm getting oscillation - "dolphin noises" no matter what I do. I have tried caps between Base and Collector on both transistors at the same time with no luck. I have tried resistors between transistors to weaken the gain with no luck, and swapped a couple collector resistors, even when I back off the fuzz knob, it still oscillates. This leads me to believe it is not the circuit thats the problem, but possibly a component or something of the sort.

Here are the voltages I'm getting (I know that Q2's collector is biased way off, but should that be causing oscillation??)

Q1
E  =  0
B  =  0.53
C  =  1.62

Q2
E  =  1
B  =  1.6
C  =  1.8

(These were on breadboard with the 2n4401s, but even on perfboard with 2n5088s, they are very similar)

https://www.dropbox.com/s/ia0cvgnjj7z3w44/20170107_195948.jpg?dl=0



Check this audio sample out, you can hear me back off my guitar volume, and then the fuzz knob soon after...
https://www.dropbox.com/s/b0k9465pf14yc5u/Oscillation.mp3?dl=0

This is on perfboard, so I don't think I can blame the breadboard or anything around that as its making exactly the same noise as it did on breadboard. I used the 2n5088s, they were from China on ebay but I'm not sure how much that would affect anything? Theres no volume pot if that changes anything, but I tried a 100k on the breadboard just to see if it helped, it did not. Also the ceramic 10nf capacitor is TINY, could this be a result of it not being able to take the voltage/current? I'm not sure on the power rating of it.

If it isn't the transistors, all I can think to blame are my ceramic caps which I don't entirely trust, or my jacks, which are meant to be stereo, but don't look like any other stereo jacks I've seen. But I can't imagine them causing oscillation? this has been bothering me for months, thought it would have been a more common occurrence, but if it isn't, then surely I have something bad? I don't like blaming equipment, but I've shown you what I've done and if everything looks as though its in order, what is there left to blame?