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Thread: BJT buffer help

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    BJT buffer help

    I built a buffer with an bjt. The emitter voltage shows up on the other side of the output cap. I changed the cap, (type and size), no change. I checked all my wiring and cant find anything wrong. Re is 10K. I can get rid of this voltage with a 100k from other side of the cap to ground. This voltage causes the following pedals to pop when switched. What can cause this and does the 100k resistor change the output imp? Would a smaller series resistor be better? Thanks

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    Lifetime Member Enzo's Avatar
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    Your cap sits unterminated? The emitter voltage wants to charge the cap, but without a ground reference on the other end, the cap cannot charge, meaning the voltage will be the same. That DC voltage makes a pop when connected to an amp. So a high value resistor to ground completes a charging path.

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    Thanks for the reply. Makes sense about charging the cap. Going nuts for a while there. A lesson learned.

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