There are people who probably have the answers to the points you make since some have already had DX QSOs using D-Star -- I haven't, so I'm looking to try this out on 10 meters. Mostly I think your prediction will turn out to be correct. I am expecting that only under near-perfect conditions between the two parties will D-Star make it via HF propagation. My experience on VHF is that it's extremely susceptible to multipath.
On the other hand, during previous sunspot cycles, I've experienced near-perfect conditions on 10 meters. I definitely would not see the present D-Star for everyday digital voice on HF, though I can see some value in a 6 meter repeater, and some 10 meter activity, with callsign routing, repeater/reflector linking, low speed data, short messages, etc. 10 meters has a lot of real estate, so I would think the wider bandwidth of D-Star will not be un-neighborly except possibly during a busy contest. But then, that's true of a lot of modes on HF during contests. It will be fun to watch David Lowe's Codec2 project evolve and see how narrow a bandwidth he can achieve. For everyday DV on HF, that may be the best path. In the meantime, I'd just like to experiment and learn. Jim - K6JM ----- Original Message ----- From: Tony To: digitalradio@yahoogroups.com Sent: Tuesday, September 07, 2010 12:04 PM Subject: Re: [digitalradio] Fwd: [KenwoodTS-2000] D-Star with the TS-2000 I have to agree that it would be interesting to experiment with the D-Star modem, but it doesn't seem practical for HF. In addition to gobbling up a fair amount of spectrum, I suspect that it would be difficult to maintain the required SNR with a modem that's 6KHz wide. The narrow-band FDMDV modem worked out well by not only improving sensitivity over WinDRM, but by allowing one to "squeeze" the signal between the adjacent QRM. The modems quick recover time was a real plus as well - not sure how long it takes for the D-Star modem to re-sync. Tony -K2MO
