Barry's ADSR & Gate voltage and logic stds
Christopher_List at sonymusic.com
Mon Feb 5 11:46:41 CET 1996
I've built two of the ADSR's in the Electronic Music Circuits, and both of them
have worked fine. The only problem I've had is with some of the gates /
switches in the 4016 and 4001 getting fried. I think that has been because,
when testing, I **used to** impatiently plug and unplug my power supply from
the modules with the power on, and since I'm using hard-disk drive power
connectors, all of the power supply lines didn't always connect up at once :P.
Other than that, the circuit does work. All of the logic levels are +V for "ON"
and 0 for "OFF". What might be confusing is the output of the comparator used
for the gate. With a gate of 0, it outputs +V, with a gate signal, it outputs
-V, which gets blocked by the diode, so it's 0v for the flipflop. This
inverting of the gate signal is necessary for the way the flip-flop works, but,
hey, it works...
Be sure to connect all of the un-used 4001 and 4016 terminals to ground.
I do all my circuits on protoboard, using the leads on the underside to connect
stuff. I have a 1:2 scale protoboard layout for this circuit that I did in
Visio. I have optimized it as best I could for size and minimum number of
jumper wires. It also includes a variable-offset inverted output. I could fax /
email the GIF to anyone who wants it...
If you're into doing your work on protoboard, I've also done these same sorta
optimized layouts (built and tested) for:
Ric / Barry's shape-able LFO
2044-based dual VCA + Exp. X-Fade
3-input clipping CV-Mixer with + and - level / peak LED's
...and several others that I'm in the middle of building...
blah blah blah...
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