I’m playing primarily with 433MHz radio frequencies lately. My primary project is a home alarm/automation system built on Raspberry Pi boards, and trying to squeeze an Arduino and battery into a small enough 3D printed case to fit on a cat collar.

Raspberry Pi Perimeter Radio System (RPiPRS)

This gadget is built around an original Raspberry Pi A, cheap 433mhz chips and sensors from Ebay, a massive boost from NinjaBlocks, and a few hundred lines of shell script. It notifies audibly when doors or windows open, sends text alerts for door, window, motion, or water sensors when armed, and will soon be expanding to utilize multiple Pis and maybe Arduinos and a robust web interface. The RPiPRS is under HEAVY development and I’m an awful developer. Stay tuned at your peril. Read more >>

Tail Pet

Building on the Pisec project and inspired by cats who don’t like to come home when they’re supposed to, the Tail Pet combines a tiny 433mhz RF transmitter, an ultra-power-efficient Arduino with a massive (relative) battery, some soldering, and a bit of custom 3D printing. A cat or dog with one of these will radio ping a home station like the Pisec a dedicated code every few seconds when nearby (range specs TBD), and can be located with a handheld beacon device like in all the movies as soon as I get around to building one. The Tail Pet is in the prototype phase, which for an untrained amateur nobody like me means I’m smashing my keyboard in FreeCAD and hoping it prints a collar enclosure. Read more >>