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Blue Box clone problem

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9/25/2002 10:42 PM

Blue Box clone problem

I've built an MXR Blue Box copy copying from one I had in for repair several years ago. I used the same op-amps (741) and the same transistors (2N3904). THe problem is that the signal is very high at the base of the transistors, but low on the collector (i.e. not loud enough at the output.) Can somebody check the voltages at the output transistors on their Blue Box so I can compare them with mine?

9/26/2002 12:37 PM
Jose	Here's wwhat I have on my B.B. Q1(tranny farthest to right on schematic going to 1 meg resistor then pin 1 of 4013)base=.525 Collector=.010 Q2- base=.068 collector=.003 Q3= base=.617 collector=.068 all emitters to ground =0vdc. Hope that helps. Jose

10/27/2002 5:01 AM
skot	is there a layout for this pedal online? i seen to remember one, but i cant find it anymore. thanks skot

10/27/2002 11:44 AM
The EH Man	Thanks a bunch! My voltages jive with what you've listed, but still it's not loud enough.

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