8 HP
Current Draw
22 mA +12V
11 mA -12V
? mA 5V
$160 Price in €

Available as an assembled Module and as a DIY project.

This Module is currently available.

Jerky CV generator

The idea for this module came from a schematic that has been floating around the web for years - 'beat frequency indicator'

The idea is to feed the circuit two signals and depending upon which one had the higher frequency the ring of 4 LEDs would light up in a clockwise or anti-clockwide direction. The speed of rotation would indicate how close or disparate the frequencies are. If the signals have the same frequency then just one LED is lit.

The original circuit used 74xxx series ICs for the logic, so it was simple enough to find the CMOS equivalents (sort of), then add gates corresponding to the LEDs and use the spare outputs of one chip to feed pots to make sequences. Then for good measure a discrete XNOR circuit was added to give a psuedo ring-modulator output based on the 2 incoming signals.

In operation this module is quite unique; the CV signals return to 0 between each step, the length of each step can vary depending on the incoming signals. Gates come in spurts. The circular LED display jerks around, sometimes it completes several revolutions confidently and then stutters between two stages, sometimes it shimmers on one spot.

At both audio rates and clock rates, this module is quite unpredictable but always seems to be putting out useful signals.

PCB = USD 18
Panel = USD 20
assembled = USD 160


Ø 4.00 (1 Votes) Average Rating
submitted Aug 20th 2019, 15:12 by motorhead412 | last Change Feb 28th 2021, 01:45 by Jabberbased