digital noise mod
2005-04-07 by charlesosthelder
Ah, spring! A young man's thoughts turn to romance, but a middle-aged
music electronics geek wonders, "what can I do to add functionality to
my already wonderful Digital Noise module?" Here's what I've done to
add two ouputs, though I'm sure you can come up with any number of
ideas:
Connect a wire to the output of the clock comparator, pin 7 of the
TL072, to the clock input of a 4017 counter/divider. Tie pins 8, 13,
and 15 to ground, and pin 16 to the positive supply voltage (with a
decoupling cap, of course). Pin 12, the output, goes through a 2K7
resistor to the base of an NPN transistor. The collector connects to
the positive supply via a 10K resistor. The emitter ties to ground
through a 1K resistor, and to the output via a 1K resistor. Now you
have a clock output at 1/10 the clock frequency of the 4006 shift
register. This provides a 0-10 V pulse. Check the pinout of the 4017
for more divisors from 1-10.
From the same pin of the clock comparator (simultaneously, if you'd
like!), connect to pin 1 of a 4024 binary counter. Pins 2 and 7 of
the counter go to ground, pin 14 goes to the positive supply with
decoupling. A seven-position rotary switch will allow you to divide
by 2 (pin 12), 4 (pin 11), 8 (pin 10), 16 (pin 6), 32 (pin 5), 64 (pin
4) and 128 (pin 3). If you look at Ken's Sub Oscillator schematic,
you'll see that this is the divider section. The output, the rotary
switch common, goes through a 2K7 resistor to the same buffer
arrangement described above. The output is also a 0-10 v pulse.
It just seemed to me that the Digital Noise module could be put to use
in timing applications. The truly ambititous (the even older or those
married longer) could add other fun stuff, like a trigger
differentiator (see Mark Media's design at
http://www.wiseguysynth.com/larry/users/mark1/mark.htm ), a slew
generator, or what have you, but I chose to keep it simple. All those
circuits reside in other modules anyway.
This should keep you busy while you wait for the new VCO pcb's to
arrive. Have fun!
Chub - hiding my hideous old self in the studio
music electronics geek wonders, "what can I do to add functionality to
my already wonderful Digital Noise module?" Here's what I've done to
add two ouputs, though I'm sure you can come up with any number of
ideas:
Connect a wire to the output of the clock comparator, pin 7 of the
TL072, to the clock input of a 4017 counter/divider. Tie pins 8, 13,
and 15 to ground, and pin 16 to the positive supply voltage (with a
decoupling cap, of course). Pin 12, the output, goes through a 2K7
resistor to the base of an NPN transistor. The collector connects to
the positive supply via a 10K resistor. The emitter ties to ground
through a 1K resistor, and to the output via a 1K resistor. Now you
have a clock output at 1/10 the clock frequency of the 4006 shift
register. This provides a 0-10 V pulse. Check the pinout of the 4017
for more divisors from 1-10.
From the same pin of the clock comparator (simultaneously, if you'd
like!), connect to pin 1 of a 4024 binary counter. Pins 2 and 7 of
the counter go to ground, pin 14 goes to the positive supply with
decoupling. A seven-position rotary switch will allow you to divide
by 2 (pin 12), 4 (pin 11), 8 (pin 10), 16 (pin 6), 32 (pin 5), 64 (pin
4) and 128 (pin 3). If you look at Ken's Sub Oscillator schematic,
you'll see that this is the divider section. The output, the rotary
switch common, goes through a 2K7 resistor to the same buffer
arrangement described above. The output is also a 0-10 v pulse.
It just seemed to me that the Digital Noise module could be put to use
in timing applications. The truly ambititous (the even older or those
married longer) could add other fun stuff, like a trigger
differentiator (see Mark Media's design at
http://www.wiseguysynth.com/larry/users/mark1/mark.htm ), a slew
generator, or what have you, but I chose to keep it simple. All those
circuits reside in other modules anyway.
This should keep you busy while you wait for the new VCO pcb's to
arrive. Have fun!
Chub - hiding my hideous old self in the studio