They’re readily available and easy to play with, they work with ... an IKEA Vallhorn motion sensor for a teardown, it’s as you might expect, a passive infrared sensor (PIR) sensor coupled ...

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 ...

(Passive InfraRed sensor) A device used to detect motion by receiving infrared radiation. When a person walks past the sensor, it detects a rapid change of infrared energy and sends a signal.