Monday, September 26, 2011

The 9-Volt Tesseract

An outer-space disco theremin! This is birthday present for my friend who loves music, has always wanted a theremin, and is pretty easy to please with bright colors and flashing lights. I've been toying with the minimum-theremin circuit for a long time, trying to create a miniature version of The Bad Hand's Imipolex G. When I finally got a stable version of the circuit, I wanted to add some big flare for my outerspace disco girlfriend! I had a leftover 4017 IC which I combined with a regular schitt-trigger IC to produce 16 LEDs flashing in luminous cacophony. The magic part is, the pitch of the theremin affects the speed of the blinky-blinky! So as you move your hand into its body, the "Tesseract" goes nuts.

Well... it worked REALLY well on the breadboard, but for some reason when I finally soldered the contraption together, it lost a big part of the effect. The pitch still does change the speed of the lights, but it is not as profound as it was on the workbench. This darn theremin circuit! It is designed to be incredibly unstable and sensitive to the environment, and so I am not too surprised that moving to a permanent circuit board changed its behavior.

I decided a nicely stained and carved up picture frame would be an ideal package for the device. Mainly, because there were these totally awesome unfinished picture frames in the art store I was standing in when I got this idea. It provides plenty of space to house the large copper plate that I used as an antenna and, most importantly, this way the "Tesseract" can easily be hung up (she has plenty of wall in her room). All the Tesseract you can expect for 9 volts. What'd you expect, a wrinkle in time?