There’s a huge market for 433 MHz alarm system hardware out there, from PIR motion detectors to door and window sensors. If you want to put them to work, all you need is a receiver, a network-enabled ...
[Brett] was looking for a way to improve on an old binary clock project from 1996. His original clock used green LEDs to denote between a one or a zero. If the LED was lit up, that indicated a one.