easyface measuring?

Started by janus, February 11, 2006, 10:08:16 AM

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janus

Hello I have a simple question, used the search function but had trouble finding it. I built an easyface and was wondering how you measure q1 and q2? do you put the black probe from the DMM on the negative battery connection or on ground and red probe on the trannie or the other way around? When I measure from ground it's really high readings and the trim gets me nowhere in the range. Which brings me to my other question I have a Vellman DMM and the readings come out when I am at 2M or 200m on the dial which is the correct place to be? I can hear the fuzz and it's really cool although I'm testing with a one string guitar!? (long story, guitars scattered around town  right now)..seems to fuzz and then have a trailing sustain fuzz as well. Never played one before so not sure if that's the thing with it but sounds good on the one string..ha! man I gotta get my car fixed. any help appreciated..
thanks,
Brian

petemoore

  Well could be PNP,,,
  or NPN
  So dis'regarding the polarity mark in the DMM Screen, and set the DMM for DCV 20v range. Clip one of the DMM test leads to ground.
  Touch the other lead to Q1Emitter, should be 0v on a FF, being it's connected to ground. write down Q1e=0.
  Touch meter lead to Q1B...take a reading note it
  Again for Q1Collector, write down the measured voltage from ground...
  Same for Q2 Emitter, base and collector...
  Mesaureing all the transitor pins voltages from ground in the powered circuit [don't forget that all these numbers are a '%age equation' with the battery or supply voltage needed as 'reference' for making sense of them...include the measured DC battery or supply voltage].
  Sounds like you've got it 'firing', if you've trimpotted Q2C's bias Resistor, you can trim it by ear, always fun and good reference to see what that looks like as far as voltage readings too.
Convention creates following, following creates convention.