Why do the loggers need to talk to each other? If they are going to, what is the third unit bringing to the party? One logger could simply send the signal when it is time for both loggers to do something. Whatever that something is.
Right, the 3rd unit does not need to transmit. The handheld needs to transmit only, the first logger needs to transmit and receive and the second logger needs to receive only. I'd like it this way because i want the periodic signal to continue even if the handheld is out of range. If I can do this in AT that's fine.
Up to 15 mile units to transmit 300 feet? OK.
Yes, 15 miles LOS, which is almost never the case. The one logger will be housed in a metal box and I don't need the higher data rate of the 2.4GHz modules so why wouldnt I order the one with the best range?
You haven't said what the idea is, other than to send "signals" from something you don't have yet to something else you don't have yet.
I'm not sure exactly what more information youre looking for. I stated my goals, the equipment I plan to use to accomplish those goals. Do I need to have the equipment in my hand before I seek "PROJECT GUIDANCE"?
Anyway, I do appreciate the input, and I will try to get the book on the ipad.