Boss HM-2 Issue

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Stevenrb718
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Post by Stevenrb718 »

I have a Boss HM-2 that powers up but doesn't pass any signal in bypass or on. I've probed the IC's and they seem to functioning properly. I traced back to the transistor at Q3 to the last point of signal. I've replaced Q3 though, and it still doesn't work. I'm getting nearly 9V to the center pin of the transistor, so it doesn't seem to be an issue there. I do have another working HM-2 that I've used as a basis, and the only difference I can find at Q3 is the working pedal has voltage along with signal on the collector and emitter sides of the transistor (about 3+V) while the broken one does not. Am I way off base here? What could be causing no sound?
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Pruttelherrie
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Post by Pruttelherrie »

Q3 is the output buffer.

Do you have a signal at the wiper of the volume pot?
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