# Nugget Fuzz



## chongmagic (Jun 5, 2019)

Has anyone built the Nugget Fuzz? I built one and it seems quite dark. 

I was just wondering if anyone had the values of the BC549 transistors that I could compare with?


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## chongmagic (Jun 5, 2019)

Also what is the best way to bias it?


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## Robert (Jun 6, 2019)

I haven't tried it this, but putting a C-Buffer in front might brighten it up some.


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## chongmagic (Jun 6, 2019)

Robert said:


> I haven't tried it this, but putting a C-Buffer in front might brighten it up some.



Do you happen to know what you were getting for the voltages on the BC549s? I don't know if you still have one around or not, just curious to see.

I did have two 1n34a diodes and replaced them with two GD570A Russian diodes and the sound is about the same.


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## tcpoint (Jun 6, 2019)

What was the forward voltage of the diodes?  You could probably brighten it up by putting a smaller value for C4 (470pf would be a good starting point).  Or you could tweak the cap in the tone control (C13).  Smaller will be brighter.  Try 10n, to start with.  You probably don't need to do both. 
What voltage did you bias Q4 to?  Just curious because I'm going to build a Nugget Fuzz, soon (after I finish my Klein Bottle).


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## chongmagic (Jun 6, 2019)

From what I recall when I measured last night the forward voltages were around .7v

Q4 had a lowest voltage on the emitter than the other 4 around 1.8v and I biased it to around 2v. The others were between 4 to 6volts on the emitter.


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## tcpoint (Jun 6, 2019)

chongmagic said:


> From what I recall when I measured last night the forward voltages were around .7v
> 
> Q4 had a lowest voltage on the emitter than the other 4 around 1.8v and I biased it to around 2v. The others were between 4 to 6volts on the emitter.


Usually, forward voltages for Germaniums are around .3 volts.  Maybe, you could try a schottky which is around the same as Germanium.  Silicon diodes are in the .7 volt range.


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## chongmagic (Jun 6, 2019)

I believe I measured that at the cathode side, I got about the same with the 1n34a's I will have to remeasure when I get home today.


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## tcpoint (Jun 6, 2019)

I've got some 1N34a that have measured .7 volts before and others in the .26 - .34 range.


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## chongmagic (Jun 6, 2019)

Yeah I'm actually getting .7 on both ends for both diodes. These are GD570A, I was getting the same with the 1N34a diodes.

Q4 the emitter is much lower than the other trannys. I believe the bias is for Q4 and Q5 so I am going to try and make them equal.


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## Robert (Jun 6, 2019)

chongmagic said:


> Do you happen to know what you were getting for the voltages on the BC549s? I don't know if you still have one around or not, just curious to see.



You need to measure the forward voltage drop using the diode test function of a DMM.  You can't determine the forward voltage drop in-circuit by measuring DC volts because of C5 (there is no DC voltage drop across the diodes because C5 is an open to DC current).


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## chongmagic (Jun 6, 2019)

Robert said:


> You need to measure the forward voltage drop using the diode test function of a DMM.  You can't determine the forward voltage drop in-circuit by measuring DC volts because of C5 (there is no DC voltage drop across the diodes because C5 is an open to DC current).



Ah doh, its .27


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## chongmagic (Jun 6, 2019)

The fuzz itself makes a farting, sputtering sound. 

The drive and sustain knobs seem to have a mind of their own


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## chongmagic (Jun 11, 2019)

So this is what my Nugget Fuzz sounds like. 


__
		https://soundcloud.com/chongmagic%2Fnugget


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## chongmagic (Jun 11, 2019)

All knobs maxed btw.


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## chongmagic (Jun 12, 2019)

chongmagic said:


> So this is what my Nugget Fuzz sounds like.
> 
> 
> __
> https://soundcloud.com/chongmagic%2Fnugget



I guess my question, is does this sound like it should? If that makes sense?


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## Robert (Jun 12, 2019)

It's a pretty nasty spitty thing.   The description of the original contains the line "Specifically designed to simulate Imminent Amp Death"... so...   

BTW you asked earlier about biasing voltages... I biased mine by ear.

Check out this clip of an original Cornish NG-2 for comparison:


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## moonlightpedalbuilds (Jul 27, 2019)

Nothing is coming out my Q1 when I use bc549c NPN. I tried to bypass the Q1 section and everything worked from Q2 to Q5. Desperate on debugging and fixing, I tried turning Q1 around and something came out of it! Sputtering and sounded horrible. Really frustrated at this point, I placed a PNP 2N3906 on it and it worked. At least some sound came out. How did it work?

BTW, I placed BAT41 diodes instead of 1n34s.


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## moonlightpedalbuilds (Jul 28, 2019)

I’m having problems with Q1 area. Looking at the G2 4th stage transistor. The one with the volume pot. I simply grabbed the resistor, capacitor and potentiometer and placed it on the nugget’s 1st stage circuit. It worked!

Btw I used a B10k pot instead of A10k pot because I didn’t have it on hand.

I had to socket these suckers to be able to test different values.


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## Bobbyd67 (Apr 21, 2020)

Necro posting cus I just built one and holy crap it sounds like s**t... I have built a g2 and ss2 and like those but why someone would release this circuit and why someone would buy one at Cornish prices is something I don't get xD.

Will have to double check everything but watching that demo, it sounded pretty similar, mine had a background buzzing but I did test it out of an enclosure and with a noisy testing circuit 9v power.

Chongmagic I know it's been a while put was your output volume kinda low on your build ?


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