MAKE Circuit Skills: Infrared Light.

This is pretty much IR 101, but there are plenty of uses in music. (Did you know that MIDI circuits use “opto-isolators” … a send-receive pair as shown in the video? Of course you did, just kidding.) The Roland AX-7 keytar uses an IR light in its D-beam sensor. You might imagine getting rid of that MIDI cable using Infrared Wireless? Not all that hard!