I have the need to set up some reliable local digital communications (say 10 mile radius from the base station) for data transfer, and to do so in a short period of time.
I would normally first think of VHF FM packet, but a lot of people are running into troubles with things like Vista and Windows 7 (please, spare me the "Linux" or "Apple" and "D*Star" messages, they're not realistic in this situation). I've seen some references to running DominoEX and MFSK-16 on VHF FM. A number of my prospective operators are running digital modes such as DominoEX, MFSK, etc. on their computers now (under XP, Vista, Win7) without problems. Would one of those modes be realistic to run on 25 watt (or higher) mobiles on 2 meter FM using vertically polarized antennas? I realize that the vertical polarization would be an issue if we want to get out of the local area, but right now the need is within a local area and everyone would be running with a typical VHF vertical. If feasible, what sub-band would we use? I would assume the FM simplex sub-bands. Is that correct? Anything else we should consider? Any special issues/problems? I would think that we would not have to reduce power since these radios are already running FM, but if not the case please correct me. Thanks. Jon KB1QBZ
