Getting an unattached hand to play a theremin

Hello!

This is my first post of hopefully many on this newly discovered site.

Ive owned a Moog Theremin for a few years now and enjoy dinking around with it.  I am an electrical engineer and wanted to automate the playing of the theremin while I play keyboards along side.  So I bought a slider from Actobotic, a mannequin hand off ebay, designed a stepper motor driver board and wrote a lovely assembly language program for my PIC microcontrollers......and the hand did nothing to influence the theremin (a valid question is "Why didnt you test the hand out before doing all this?") .  I was forewarned of this failure a few days previous when a friend more versed in electromagnetics than I am said "I hope the hand can activate the theremin's field".  Hmmm...I had just assumed the theremin worked via proximity of ANYTHING.  I now know that there needs to be a capacitance between the theremin and the object playing it.

So I now turn to the electromagnetics experts.  What can I put on the mannequin hand to make it capacitive?  A piece of foil?  Does one end of the foil need to be connected to anything?  Help!  I wanted to get this thing running for a Halloween display.  I got 6.5 days.

Bill

Grounded foil.

..inside the mannequin hand (if this possible) to save the exterior.

Or a tangle of wire instead of foil (inside).

So I bought a slider from Actobotic, a mannequin hand off ebay, designed a stepper motor driver board and wrote a lovely assembly language program for my PIC microcontrollers......and the hand did nothing to influence the theremin 

The PIC is the problem, try attaching the hand to an ARM processor ;-)

Changing Proximity to ANYTHING grounded will work.

I've waved a plugged-in Bass Guitar at a Theremin for comic effect.

Botski....Have you seen this video?