433MHz Receiver
You need a decent shielded "super-heterodyne 433MHz OOK receiver" board for this to work (around £2 on eBay) Connect PWR to +5V, GND to GND and Leg-0 to Data. Numbers above 5000 or less than 0 indicate a valid signal which gets a smiley face. Lower sub-100 numbers are background noise. Should work with any 433MHz transmitting gadget. Don't use the cheap sub-£1 433MHz receivers (they don't use a crystal) that come bundled with the 433MHz transmitter boards as they're much too noisy. Wiring diagram at www.securipi.co.uk/codebug-433-receiver.png