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 ...

Instructables user [willnue] wanted to build a DIY Tweeting alarm system from the ground up, but reconsidered after taking a close look at the scope of such a project. He settled on using an off the ...