This is a raw 12HP 1U Intellijel Tile version of the Mobius PiLL. It uses two cross-coupled Phase locked loop (PLL) ICs that go in and out of chaotic zones at audio rates. If you like making electronic noise, this module is for you. Oh yeh, it has vactrols.
It is a pretty simple build  and capable of a wide variety of sounds. The demo below is my usual noisy effort but it can be tamed if you choose to feed it CVs from sequencers.

There are 5 inputs, everything affects everything:
FM IN - feeds both PLL ICs
CV Range 1 & 2 - these control the vactrols. The control circuits are very simple.....a resistor and a vactrol!
CV 1 & 2 - these inject a signal into the VCO control input, shove in anything from audio to CV rates and see what you get.

The 4 outputs are from the PLL VCOs and the phase comparators, all are pulse/square waves running from 0-approx 5V.