Range finder using RF and an arduino?
Basically, I would like to create a "finder" unit and a "hider" unit[s]. My thought would be to us RF of some sort, so the "hider" unit will spit out a certain frequency, that the "finder" will pick up and react to (in this case, speed up the blinking of some LED's and turn some servo's to set levels).
This doesn't need to be exact. So long as I can detect a decent range so I have a cold, warm, warmer, and on fire points to use, it'll do the desired deed. Price is another factor, as I would like to keep this around the ballpark of $30 per unit.
Thanks in advance!!