video://www.youtube.com/watch?v=3b4aDtxCImQ&feature=player_embedded
Here’s an interesting DIY electric fence for keeping dogs away from cats by using IR sensors that sense when dogs come to eat cats’ lunch. Might be a good idea for some of you who might be in the same situation.
I wanted this setup to be cheap, so I decided to use an infrared “trip-wire” system. On one side of the hallway is an always-on infrared emitter, and on the other side is an infrared receiver, an AVR ATmega8 microcontroller, and a buzzer. The micocontroller conti