It is controlled by 5 knobs, 8 switches and one push button.
It has 3 oscillators (Yellow, Green and Blue knobs). Osc 1 produces audio frequency ranges whilst osc 2 and 3 produce LFO and audio freqencies.
Osc 1 goes to the output through a simple passive filter (Red knob) while osc 3 can be switched to the output but bypasses the filter.
Osc 3 modulates osc 1's pitch by the ammount set by the orange knob. This modulation can be shaped by 2 shapers which can be switched on and off. Osc 3 can also gate osc 2.
Osc 2 can gate osc 1 and passes through an inverter after which it can gate osc 3.
There is also a push button to trigger the unit (actually a power button), a switch to lock the power on, a power led indicator and a battery cap switch which lets the unit run for a short time after power off for springy type noises.
A certain configuration can even produce sounds that stop after a time determined by osc 3 which is good for maker sound effects. (see 4:44 onward)
The knobs all go backward as you may have noticed. This is because I'm using logarithmic knobs which make the oscillators easier to contol when wired up the wrong way round.
This is my first build. Everything works perfectly but I found I'd barely alloed myself enough room to fit everything on the stripboard. I'll make the next one bigger.