Hi everyone,
I don't know anything about electronics so I hope you guys (and gals) can help me out. I want to design a simple tripwire hooked up to a simple transmitter, minimum range of 200m. The receiver has to be smaller than a pack of cigarettes and have some sort of silent alert (LED light). I'm trying to catch an intruder in the act while i'm at school. Being on a college budget, the cheaper and simpler, the better. If there are already kits available, where can I find them. thank you in advance.