I'm impressed by how compact this is, but if anyone is looking for a more "production-ready" solution, I've had great success with ggwave [0] - it even sounds pretty decent in the slow modes (as well as having an ultrasonic mode).
Obviously you won't be using any of this for regular communication, but there's a whole world of cool uses for sending short (up to a few bytes) messages over the air. And despite knowing dial-up modems exist, people are constantly impressed by novel applications of it.
Obviously you won't be using any of this for regular communication, but there's a whole world of cool uses for sending short (up to a few bytes) messages over the air. And despite knowing dial-up modems exist, people are constantly impressed by novel applications of it.
[0] https://github.com/ggerganov/ggwave