Theremin-inspired fart machine

We genuinely believe this to be a first: a Theremin-controlled fart machine! Walk too close and it'll fart at you!

Direct from the inventor himself:

It's basically a dual 555-based square wave oscillator which uses a high pitch sound and a low pitch sound and logical ANDs them together (with a 3 input 4000 series NAND gate) with the ambient 50Hz mains picked up by AC coupling between humans and the bit of wire.

It's a bit flakey but you get some ripe ones occasionally. There's a really crappy R-C low-pass filter and a primitive single transistor audio amp on the output stage to give it some wumph! Amp transistor gets a bit toasty but the severe lack of current from the Tescos value battery seems to keep it coolish.

I might even do a schematic if I can be arsed...

Sound samples to follow shortly...

©2006 Chris Smith