[sdiy] Theremin controller

[Grant Richter]

>
> Compared to 'true' Theremins designs ( who do not need a vco chip  
> to produce a
> sound) the drawback  is that the  antenna range is limited to  
> 10/15cm max...Else
> it is stable and reliable :) Well i bet that for a similar effect  
> there
> areprobably much simpler schems , but this one is a good base to  
> work on...
>

Put a 40 millihenry inductor in series with the antennas. That should  
extend their range of sensitivity to 50 to 75 cm.

You may have to adjust the main frequency of the oscillators feeding  
the EXOR gate.

I have built three theremins from scratch and the antenna matching  
inductors are crucial to best operation.

Ask any ham, antennas work best with a matching network.