A simple RC Theremin with pitch antenna just for having fun.
The Theremin was invented 1919 by the Russian physicist Leon Theremin. It is one of the first electronic music instruments and one of the few instruments that can be played contactless.
The present theremin, like the original one, consists of two resonators. The reference oscillator using a 16MHz quartz to produce a fixed frequency of 125kHz. The variable oscillator, built with a VCO, produces a frequency that can be influenced by the hand near the antenna. The mixer (a simple XNOR) provides the difference of the two frequencies that is then filtered and made audible by the TL072.
Download the makeaway manual:
The complete part list including reichelt order numbers:
More information can be found on the Open.Theremin Website athttp://www.gaudi.ch/OpenTheremin/