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Fuzz Face Bias

Started by lessthanmatt88, August 12, 2006, 09:49:38 PM

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lessthanmatt88

I'm trying to bias the fuzz face i just rebuilt, it used to work pretty well, but now when i adjust the trim pot, i get no change on the collector of Q2's voltage, all i see is the battery's voltage (9.1).  I changed out the trim pot I had just in case and i've looked over all my connections and I have all components connected properly, as well as transistors that work well.  I'm not getting why my resistance isnt changing this, it must be a short somewhere but im not seeing where it would be.  I just keep getting this farty splatty fuzz sound and no change is happening.  Im gonna keep looking over the schematic and my layout for any more errors i may have missed but i think i found them all. 
Any help?

QSQCaito

Read HOW TE DEBUG thread, post your voltages. This might be the easiest way to let the pros:P detect your error

Bye bye!


hope it helps

DAC
D.A.C

petemoore

now when i adjust the trim pot, i get no change on the collector of Q2's voltage, all i see is the battery's voltage (9.1).
  I know you said you changed the Q2C pot, but the first thing I check when ^ that happens is the variable resistance of Q2's C resistor pot while being turned.
Convention creates following, following creates convention.

lessthanmatt88

i checked both of them out of the circuit and they work perfecly, as i expected.  I'm gonna check if its actually doing anything in the circuit or if its shorting out somewhere.

lessthanmatt88

Found the problem, i grounded the bias pot when i should have grounded the fuzz pot instead...  dont know how i didnt catch that before i posted this thinking i had a real problem...