“A piano for your pocket? Sure!
Using a printer toner transfer, copper etching solution, and a Teensy 3.2 we make a tiny MIDI controller that responds to a simple touch of a finger.You’ll need some materials:100mm X 70mm copper PCB Teensy 3.2 Ferric Chloride Design Software (I used Illustrator) Arduino IDESoldering toolsDigital Audio Workstation (I used Ableton Live)”