RF LED question

Thread Starter


Joined Oct 18, 2008
Hello i was wondering how i could transmit a signal to a receiver to tell a LED to light up? Thats basically the question. The whole project is this, to build a laser alarm system. I already know how to set up the laser system i want build. That was the simple part but how would i lest expensively build a system where when the laser is broken it transmits to a receiver turning on LED. And i would like for the transmitter range to be able to cover an acre.

thanks any ideas will be great.


Joined Apr 20, 2004
To use a transmitter, you usually have a press-to-talk switch. Arrange your laser trip wire to do the same function.

The receiver usually has a squelch function that requires a receipt of the transmit signal. Often, the squelch signals the receipt of the transmitted signal by turning on a LED.

Depending on the frequency and terrain, 100 mv of RF should give the coverage. Check on some inexpensive walkie talkies from Radio Shack.