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bumblebee help - no output

Started by miter53, May 28, 2013, 01:37:40 AM

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miter53

I've put together a half a dozen boards now without a major problem, but I'm having trouble with this one. I'm getting no output, although some noise when the pots are adjusted. I've traced the continuity of all the legs between components in the signal path from one end to the other, and it seems fine. I've got 4 germanium transistors that all test fine on my DMM (two AC125K, a AC188K, and a 2SB172), and I've tried them all in different positions. Voltages are:

battery: 9.33
Q1: .06 e
      1.49 b
      9.13 c
Q2: .05 e
      .05 b
      9.13 c
Q3: 0.0 e
      .05 b
      .99 c

All the pots are dimed. Since I socketed the trannies, the voltages were taken on the leads of the transistors, not the pcb.

Q3 c seems low. I'm getting 9.13 at one end of R9 and 1.3 at the other, but .99 after the pot and R8 makes sense.
"Only sick music makes money today."-Friedrich Nietzsche
My photography website: http://michaelteresko.com/

miter53

I had a hunch it was something stupid simple. Output jack wasn't making contact with the plug! I fixed up an audio probe and traced the signal until I had the Doh! moment. It's working fine (and sounding good)...ready to box up.
"Only sick music makes money today."-Friedrich Nietzsche
My photography website: http://michaelteresko.com/