Alright guys, i want to let you know i'm a total noob in electricity and stuff. My specialty is aviation repair. But this should be a simple question to answer i think..
I want to build a 2 part device. A transmitter and receiver. I am going to have the transmitter hooked up to a trip line, and rigged so that once the line is tripped, the transmitter receives power and sends a signal the receiver... Oh a half mile away. Maybe just a quarter. And when it receives that signal, ALL i want it to do is light an LED light. So basically, 1. Trip and 2. LED shines at receiver.
Is there a way to do this? Maybe disassemble a pair of walkie talkies from a garage sale? Or a small AM reciever and transmitter? Something that would run off of at most 4 AA batteries for both parts. Note the reciever will only use power once the line is tripped. Anyways, I THINK i laid that out with everything i needed. I've tried doing so much research on this stuff with Google and can't seem to find or learn what i need. It's all smoke and mirrors to me right now Thanks!
Reliable range of half mile is tough, especially if the transmitter and receiver antennas are close to the ground, even with a 1W output VHF transceiver.
With an elevated, external, directional roof mounted antenna, you might stand a chance.
Legality is another issue. In the US there are no license-free VHF radio frequencies where you can do this without risking a stiff fine if caught.