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Subject: Re: [motm] daft circuit idea time

From: media.nai@...
Date: 2002-10-30

>> There is a chip (been around 20 years) called a UN2003 that is made for
>this. Cheap, too!
>
>you mean ULN2003 - six buffers in a 16 pin dil..?

I don't care what it's called as long it's not about digital audio!!


Anyway, you can build a simple circuit using a transistor:


Bypass
----------------
Gate 10k / |
-------/\/\/\---------+-------| 2N3904 ---
| | \ ///
| - |
| 1N4148 ^ |
| | |
--- --- ---
/// /// ///



The resistor value isn't critical. Neither are the transistor specs.
And the diode is a safety feature :)

Keep in mind that compared to electronics, human feet are slow, so many
bypass inputs are heavily "debounced". These might require the addition of
an RC pulse strecher between the input and the base of the transistor. I
had to add one to clock my Vortex from 808 drum triggers.