The theremin is is an electronic musical instrument controlled without physical contact by the performer. It is named after its inventor, Leon Theremin, who patented the device in 1928. It is one of the first electronic musical instrument. At that time, the only electronic amplifying device was the triode vacuum tube. Now, the theremin exist in many different flavors, ranging from gadgets to professional musical instruments.

An old vacuum tube radio was in my possession and it contain many of the needed parts to build a theremin. I begun to collect schematics, and to read more about electronic oscillators, a domain I never worked with at the development level. I completely dismantled that radio and begun to experiment with different kind of oscillators, first a simple one, and second a more evolved one, the Clapp oscillator. It have the advantage than the resonant circuit that fix its frequency can be physically separated from the rest of the circuit (the active part with the tube), that without impacting the frequency stability of the oscillator. That research allowed me to separate the 2 antennas from the case of the device.

The result is an very unique theremin which exceeded my expectations. You can find the schematic, some pictures and sounds here: Black Star Theremin on github

I named that theremin from the only real black star, the dog of the house I was living when developing and building that musical instrument: