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Optical Theremin Built From Snap Circuits

Snap Circuits Theremin

Using Radio Shack's Snap Circuits kit and a common 555 timer IC, member KRA5H designed this simple optical theremin to give you an idea of what playing a gesture controlled instrument feels like (or doesn't).  You'll have to custom-build the 555 chip piece, but don't worry, he tells you exactly how to do that too. 

Some purists will point out that an optical theremin isn't a true theremin, and technically they're exactly right.  Optical theremins vary their pitch by the amount of light hitting an optical sensor, whereas traditional analog theremins used the difference between 2 RF oscillators and capacitance to both sense the player and produce a tone.  However, not everyone can afford a $200 instrument or has the technical moxy to build one from scratch, so personally I'm happy when such a simple project like this comes along that can introduce folks to the idea of a theremin.

If you're ready to try building it yourself, head on over to for all the details.

Read:  Build an Optical Theremin--Improve Your Snap Circuits by Adding a 555 Timer Integrated Circuit II (