video by SMMP
via this auction
"This is a Synth/Noise Generator/Toy/Portal I built completely from scratch. The circuit I designed starts from basic schematics you can find in the datasheet of the main sound generator IC (40106 and 4046). The ways the oscillator interact are based on almost random routing and wiring, going through several logic gates, including a 4066 if I remember well, for automatic switching. There are 2 LDR, although the video don't make much justice to their function. If on certain setting, it will produce different sound at night rather than during the daytime. You can experiment pointing a torch to the LDR or to bend over them to modulate the sound (it affects the behaviour of two oscillators, in ifferent configurations).
There is also a nice area with bolts sticking out. If you touch two of them, particularly after licing your fingers, you can dramatically control the sound.
There are switches that controls the routing of the oscillators or enable larger capacitors, LEDs to make it funky, and some sort of CVin (minijack). I played a bit with conductive dough I made with my son, but it would be cool to try it with veggies and fruits, more bodies touching while exchanging fluids and so on.
The case is made of stained recycled pallet wood (pine) which I joined using fingers joints and then it's been sanded and polished several times using danish oil. The panels are old circuit board that were skipped in an educational environment and that I recycled from being dumped. Rather than using them as PCB here they are used like panels."
