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Please check my readings on my FuzzFace clones.


 
2/27/2005 3:19 PM
Humbucker
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Please check my readings on my FuzzFace clones.
I just built a couple of FuzzFace clones and I've got them set up to read appx.-4.5volts on Q2's collector but apparently I need to be concerned about the voltages in other areas of the circuit, or so I've been told anyway.  
 
The first fuzz has a pair of NKT275 Germanium transistors, I used GEO's gain testing method and came up with Q1=65hfe and Q2=70hfe. As for resistors, in R1 I've got the standard 33k, R2 is the standard 470 ohm, R3 is a resistance of 5.25k, and R4 is the standard 100k.  
The voltages read as follows...  
 
Q1 base= -0.14V  
Q1 collector= -0.96V  
Q2 base= -0.96V  
Q2 emitter= -0.78V  
Q2 collector= -4.8V  
 
 
The next fuzz has a pair of Germaniums that I got from Small Bear and according to Steve Daniels Q1=89hfe and Q2=141hfe. The resistors are as follows......R1=39k, R2=470ohms, R3=6k, R4=150k.  
The voltages read as follows...  
 
Q1 base= -0.14V  
Q1 collector= -0.94V  
Q2 base= -0.94V  
Q2 emitter= -0.8V  
Q2 collector= -4.5V  
 
 
BTW, both Fuzz pedals sound great IMHO, I was just wondering about these different voltages, if they're pretty much in line with a good old original FuzzFace? Do these numbers look ok?
 
4/1/2005 7:15 PM
Ian Anderson
here's what I found on the General Guitar Gadgets website...  
 
Q1  
Collector  
.5  
 
Base  
.1  
 
Emitter  
0  
 
Q2  
Collector  
4.5  
 
Base  
.5  
 
Emitter  
.4  
 
 
Hope that helps... Ian :)
 
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