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Plug-in buffer

Still on holiday from work, but my back is on the mend thankfully.

I've been tinkering with another pedal (more to come) and it's a bit of a strange one. It has an unusual switching mechanism which means that it's not bypassed in the usual way. I'd heard others report that this effect suffered volume loss when engaged, but my breadboarded circuit suffers from volume loss when in the signal path, engaged or otherwise. In fact, the volume difference between on/off states is negligible in my case.

I wanted to try a few things, and one was whether buffering the effect would make any difference. So I conjured up an idea to make a plug-able buffer that I could use for this purpose now and in the future when breadboarding circuits.

The circuit I used was the bi-polar transistor buffer circuit described in the link, and here is what my finished item looked like.

plug-in buffer
In the end, this particular circuit didn't benefit from the addition of a buffer, but that's another story.
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