Here’s the sensor on it’s breadboard:
https://www.instagram.com/p/Bh7mvmUgf-o/
and a little video of it in action
https://www.instagram.com/p/Bh7tQTqAceT/
You can just about make out the shadow of my hand activating it.
When it detects movement it sends a packet of JSON to the MQTT server, and I have various bits of config to drag that out into sensors. In the photo you can see the PIR itself, an LDR to detect light level and I’ve since added a DHT22 which measures temperature & humidity.
The origional idea was from the BRUH Automation vedio here: https://www.youtube.com/watch?v=jpjfVc-9IrQ