[sdiy] Trigger delay circuit

[>>>marjan<<<]

Roland made it quite simple, look the SH09 schematic:
http://www.electromusic.com/takeout/sh09.pdf
you'll find it in the part where lfo sine wave is delayed.
You only need one transistor in front of it to convert
moog gate to standard one.
I'd make something like this: s->v trig converter, diode>
1Meg pot (delay time) to noninv in of comparator (or just
opamp), 10u or smaller to gnd (charging cap), diode in parallel
to series diode/pot, with cathode to v trig input. Comp inverting
in should be set to voltage of your gate. Gate in charges
cap thru pot and voltage rises until it reaches gate voltage
when comparator switch (that's why you need to make inv in
set to gate voltage, best make it trimmer voltage divider)
and puts high output, put some resistor to output if you need
lower voltage than +V. When gate goes low (to gnd) other diode
conducts and discharge the cap switching comparator to low output.



marjan