In the Adafruit Arduino Lesson 10, Pseudo-Theramin, an Arduino Uno is combined with a light-sensitive cadmium sulfide (CdS) photocell to make a light responsive music machine. This project allows you do do the same with an Adafruit Trinket or Gemma mini-microcontroller. This project costs less and works in smaller circuits or wearable projects.

Changes in light intensity on the photocell will change the pitch of a note on the piezo speaker as you wave your hand in front of the cell. While not a true theramin (which uses changes in a circuit's reactance), this project is much simpler to build.
This guide was written for the 'original' Trinket/GEMMA boards, but works with either the original or M0 Gemma. We recommend M0 boards as they're easier to use and more compatible with modern computers!
Last updated on 2017-10-19 at 05.15.21 PM Published on 2013-09-19 at 10.23.36 AM