We use a receiver unit with three remote detector/transmitters. They will transmit at least 500 or so feet, which is the distance the 2 most remote are from the house. IIRC the receiver will handle up to 6 transmitters, you can program in a unique voice message for each one to play when it is set off. The transmitters are battery powered and play the "low battery" message when they start getting weak.

We used two different one channel systems before this one, and the six channel seems to be more robust than either of them were. I will see what make/model it is later today and post that info.

All three systems have some failures to detect in heavy rain and will throw a lot of false hits when a spider spins a web in front of them. We call the false hits "ghost cars." \:\)


"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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