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Muff problem

Started by FujiLim, January 31, 2009, 08:13:24 PM

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FujiLim

Hi all, this is my second project after I have successfully builded red fuzz. I made green big muff (layout from tonepad) using 2N3904 transistors (hfe abut 145). But loud poping is hearable, and it doesn't seem to sound well when playing thinner strings. I have measured voltages:
battery 9,63
Q1  C 6,81   
      B 0,85
      E 0,08
Q2  E 0,022
      B 1,03
      C 1,54
Q3  C 1,21
      B 1,03
      E 0,22
Q4  E 0,76
      B 1,46
      C 6,33

petemoore

Q1  C 6,81   
      B 0,85
      E 0,08  This one looks like it might work
Q2  E 0,022
      B 1,03
      C 1,54   Something is keeping the bias voltage very low on this collector
Q3  C 1,21   Same thing with this one, collector is near ground/Base
      B 1,03
      E 0,22
Q4  E 0,76
      B 1,46
      C 6,33   This one should be able to pass/amplify signal
  I would check the resistance between the collector transistor leg and the PS. Q's 2 and 3 arent' biased, perhaps there's a trace or cold solder around these.
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