This is the Theremin my brother and I cooked up, it only took about an hour to make and set up, and half of that was dedicated to actually finding a third radio for us to use!
And there's something I forgot to mention in the video:
When setting up the Variable Transmitter, before you clip the alligator clip to the antenna, you need to disconnect the antenna from it's internal receiver... I think that's what you'd call it. Whatever the case, when you've busted open the radio, make sure you disconnect whatever the antenna would be connected to.
ALSO THIS IS IMPORTANT
Do not tune the Variable Transmitter to 1500kHz, I meant to say 1045kHz like the Fixed Transmitter.
And here's the video on how to...