I'm looking for some help. Looking for a simple circuit. Proximity sensor not IR based. Not line-of-site? Answered
I would like to have two devices(Circuits) know when they are apart from eachother.
Example device A is in a fixed location. When device B moves away from device A an LED flashes.
I'm looking for a distance of 10 feet total.
I don't want to use a line-of-site circuit.
Any advice/guidance would be great!