CMOS Theremin

This theremin is based on this layout from Paul in the Lab. It runs on two 4069 chips and the antenna only controls the frequency. As the signal can be a bit low, I added an extra Ruby Amp circuit to boost it. Although it is not a perfect device range-wise and it is not an original theremin, it is really fun to play with.

If you want to build it bear in mind that the antenna and the grounding are tricky to get right (I also had to add an extra jumper that was not on the original circuit).