Hi Marc,
I am not clear about what you are trying to achieve. I get the impression that that you want the receiver to receive the signal from the transmitter when the distance between them is between zero and 10 feet but you do NOT want to detect the signal when the distance is MORE than 10 feet. Am I correct in my understanding ? In post #1 you say that you want to send one or more signals but in post #3 you say that you just want to light a lamp when the signal is received. If your requirement is as described in post #1 then what is the nature of the signals in terms of bandwidth and the maximum number of signals you need to transmit. There is a big difference in sending a simple on/off signal and 100 high definition television signals.
Les.