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4017-Based Analogue Synthesizer Sequencer

Yoa01

Jun 18, 2012
214
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Jun 18, 2012
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214
Hi all,

So I had this neat idea in a dream (yes, I dream of this stuff, I'm weird) of using a 555 oscillator to clock a 4017, and use that as a 10-step sequencer for controlling voltage-controlled analogue synthesizer modules. I drew up a schematic in LTSpice:

http://imageshack.us/f/213/4017seq.png/

I know, I know, things aren't exactly proper, let me explain:
-I used VC switches instead of normal ones because LTSpice doesn't have normal switches.
-I did not draw jacks or even grounds by the outputs because, well, there isn't much room to and LTSpice doesn't seem to have those either.
-Some of the resistors are actually potentiometers: 500k by 555, all 10k around 4017.
-I used 470ohm resistors to lessen current going to the LEDs so that they don't asplode.
-The vactrol 500k resistor will actually use a switched jack: one will use the input voltage to drive the vactrol, the other is just a potentiometer.
-The notes denoting ind CV and Gate outs, CV controls, and LED indicators hold true for all 10 outputs.

The U1 4017 IC is a Fairchild CD4017B, the vactrol by the 555 is handmade, the reset and hold ins each have two inputs, one attenuated, the '5th outs' is the carry out pin, and all unconnected wires are jacks. I'll provide any other info you may need.

Having not a 4017, I can't test this, but would it work? It seems like it would. Thanks!
 
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