Walt, If neither A nor B can hear either C or D, then generally speaking that also means that C and D cannot hear A or B and there would be no interference problem. There may be rare cases of one way skip, but nothing can do anything about that.
The hidden transmitter effect occurs when you have an automatic machine (or someone who can not hear well due to receiver problems, or a huge difference in power levels such as QRP vs. QRO), and the automatic station transmits due to responding to the calling station. That calling station can can not hear the station(s) that the automatic station can hear. And going to VHF or more doesn't make any difference. In fact, the hidden transmitter effect has been a problem with packet radio for decades. 73, Rick, KV9U DuBose Walt Civ AETC CONS/LGCA wrote: >If A and B can hear each other but can't hear C or D then if A or B transmits >and C is receiving D, then C is QRMed and can't copy D. > >This is something that happens quite often on HF and I don't think that any >amount of coding willremedy this problem. > >Walt/K5YFW > > >
