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Subject: Re: [motm] module idea & question

From: The Old Crow <oldcrow@...>
Date: 2000-04-25

> > Which leads me to my next question, is there any simple way to make a gate
> > to trigger pulse convertor? -Nate

> Sure, use a 555 timer as a monostable, set for a 100us output pulse.

Ultracheap method (fits in one end of a patch cord):

gate >---/\/\/---+
22K _|_
___ 0.01uF
|
|
+--------> trig ___|\___
_|_
1N914 /_\
|
_|_
\_/ (ground)


..at least I think that's how I used to make these. Just some dinky
step differentiator with a period of about 220 microseconds and a diode to
keep the return step (gate returning to zero volts) from creating the
negative differential pulse. __|\__ __
|/ <-- that thing


Nearly as cheap method but needs PIC: program one of the 8-pin PICs to
output triggers on a few pins for each gate input. Can then do fun stuff
like an output pin for each rising gate edge, an output pin for each
falling gate edge (trig on release) and an output pin for trigger on both
edges. Could even fudge a konb in there to set the trigger pulse width.

Crow

/∗∗/