This is a square-wave generator that is modulated by a LFO (low frequency oscillator). The LFO basically tweaks the pitch a controlled amount at a controlled rate.
Controls are blue for the frequency of the square-wave, pink for the speed of the LFO and yellow for the amount of modulation. There is power switch with a yellow LED that blinks in unison with the rate of the LFO, as well as a white volume control on the side.
The knobs and enclosure were salvaged from vintage color photography equipment hence the CMY color scheme.
This now has a home with Lily Taylor.