I don’t enjoy coming home to a dark house, and Switchit is my solution to turning on the lights before anyone gets home. It started with lights, but has evolved to also putting the kettle on, for when you want tea on your arrival home, you know? It can also change the colour of the light in the kitchen. I’m working on an interface for our air conditioner – it’s starting to get hot here.

I always have a few projects on the go. Most lose my interest pretty quickly. However, Switchit has kept me hooked for months. It has evolved into a system which operates a variety of the appliances in our home using mobile phones. The messages communicated between phone and device are delivered through a server on the Internet. This means we can control these devices from anywhere in the world*. (*Where that part of the world is connected to the Internet). Given the distance each message must travel, I’m really happy with the speed at which a device responds to my command.

So, you’re still reading? Okay, here are some more details and pictures.

The components which make up a device controller

The components assembled into a device controller

The components include an AtMega microcontroller, relay, a status LED, and a 433Mhz receiver. The on/off devices contain a relay while the colourable lights exchange the relay for an array of Darlington transistors which drive RGB LEDs.

The next photo is of the inside of my Christmas tree, into which I’ve cable-tied a controller.

A controller built into the base of my Christmas tree

Devices need to receive commands from a 433Mhz transmitter, which in turn is connected to an Internet service through my local ethernet network. To accomplish this I’ve built a 433Mhz transmitter onto an Arduino board and ethernet shield.

Ethernet & 433Mhz transmitter

Let me know if you’d like to make one too! What would you connect it to?