Daenris writes –
This project uses an RF receiver module to trigger a pulsing LED Heart when the transmitter comes within range. I made this for my fiance for Valentine’s Day this year.
I have yet to fully test the range, as I haven’t actually taken the transmitter out of our apartment building since I just finished it today. The transmitter/receiver pair that I used is hypothetically capable of up to 500 feet, though that is the open space line of sight range. I haven’t yet added antennas to either the receiver or transmitter box, but that should hypothetically improve the current range.
instructables : Pulsing Hubby Detector – Link.