I want to build a basic(but decent sounding) theremin unit which i can A/B with my guitar so I can play the theremin through my effects and into my amp. Does any one have a schematic or even better layout for such a device. If not what modifications would I need to perform to make the output compatable with my effects/amp?

PS. I would prefer a non tube circuit since the unit needs to be very small.

PSS. And the parts would have to be easily obtainable

The archives here are pretty amazing.

Here's a couple of prime threads. Check out the links within.
http://www.diystompboxes.com/sboxforum/viewtopic.php?t=16856
http://www.diystompboxes.com/sboxforum/viewtopic.php?t=7499

Good luck with your build!

-Peter

I make a commercial "optical" theremin (the Frostwave SpaceBeam). Why I went for an optical setup (there is an infrared beam that is reflected back to the unit) is because it is much more stable, and you can 'play' it by waving the headstock of the guitar in front of it, if you mount it horizontally on the front of a speaker or mic stand. A lotta fun!

yeah that was the type i was after do you know if there are any schematics on the internet for a simple model like te one you described

there is a lot of stuff under 'optical theremin' at google, but here is a very simple one, just relies on you blocking the ambient light to a LDR.
http://www.maxiespages.com/images/Theremin/optical-theremin.gif

If you want a reflecting beam one, it gets a lot more complex..