Kosmo gets rungled

After some breadboarding, I went ahead and designed a rungler in Kosmo format.

I included the loop offset switch and knob discussed in the previous post. Also on the front panel is a feedback switch. This enables or disables sending the output of the last stage of the shift register to be XORed with the input to determine the next bit to be loaded in. Feedback on is the “normal” configuration, hard wired in the Benjolin, but you may find it useful to turn it off sometimes.

I included a knob that lets you vary the threshold that determines whether the DATA signal is “low” or “high”. This does nothing very useful if DATA is binary (a pulse wave, for instance), but can have an effect when it is non binary (ramp, triangle, sine…).

I used a CD4016 shift register instead of a CD4021, and a 2N3904 transistor instead of a BV547, because I had them.

As mentioned in my post about the Kassutronics Wavefolder, -9 V regulators are not plentiful; for that project I substituted ±8 V regulators. Here I did use ±9 V, having ordered some Diotec DI79L09ZAB, practically the only -9 V regulators I could find, from Digi-Key.

There are two copies of the output sequence available on front panel jacks — two, to facilitate using feedback. (Use the rungler to control the frequency of an oscillator that clocks the rungler, for instance.) Two more jacks provide GATE, the state of the last stage of the shift register, and the XOR of the input and GATE (as 0 and ~5 V levels). Indicator LEDs show the state of CLOCK, DATA, GATE, and XOR.

Schematics, design files, and Gerbers may be found in the git repo at https://gitlab.com/rsholmes/rungler.