stupid NAND oscillator

PHOBoS

I had this idea of connecting 2 pulse delay circuits to make an oscillator with 2 outputs, with timing control for each output. And after some
breadboarding I got a working circuit Very Happy

. But only when I saw what it did I realized that the idea was rather stupid. Instead of wasting 4 NAND
gates you can do the same thing by making an oscillator with adjustable pulse width and add an inverted output. And you can make 2 of those
with one NAND chip.

However there is something else I've been thinking of building for a while, a sequencer with CV and steptime control for each step. I was thinking of
doing this with 555 timer chips but now that I had this circuit breadboarded I wondered if I could use it to do the same thing. So I breadboarded a
second circuit and linked them in a loop, and it worked. For a sequencer it needs to put out a control voltage, which can easily be done the same
way as with the baby 10. A potentiometer connected to the output, and then all of them connected together with diodes. But there's one small
problem, the output is inverted. So I added a transistor to take care of that.

The thing works like a shiftregister but instead of a CLK each step has an adjustable length. It needs a low to high signal on the input to get it
started and you can link the output back to the input to keep it going. Although you can get 2 steps with one chip I think it would be more
practical to use it for only one step and use the other gates for something else. One could be use instead of the transistor and the other one maybe
to add something like a skip function. This way you can make small modules with a connector that you can plug into a piece of (slightly
modified) stripboard to link them together. And by mounting the pots on the PCB you don't need any wiring. With 2 steps for each module you
would have 4 pots which makes the PCB much larger or you'd have to connect 2 pots with wires.

Another useful thing would be a master module, with a CLK generator and maybe some controls to add more or less bits into the "shiftregister",
but I don't know how well this would work. And an output module with a voltage follower to buffer the CV output and maybe offset control.

stupid nand oscillator.gif

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stupid idea on the left, better equivalent on the right

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