Morse code can be sent using low power, ... I don’t know about this Arduino based decoder but I have tried a lot of different soundcard/computer software based ones.

Magic Morse is a mathematical algorithm that [Ray Burnette] wrote a few years ago to make it easy to send and receive Morse code. When he first wrote it, he designed it for a PIC, but since then he… ...

This project uses two Arduino to communicate with each other using light by means of Morse Code. As a more advanced project, it has some complex array usage and investigates converting switch inputs ...