On Aug 30, 2009, at 9:19 PM, john_ke5c wrote: > > >Digital voice on HF will NEVER catch on because it is a strong > > >signal mode, and HF is the home of weak signals, well except for 80 > > > > Never is a long time, and vocoder technology marches on. Already, > > the biggest limitation is not technology, but patents and what we > > hams can get hold of for an affordable price. > > Free AMBE wouldn't eliminate the 10 db s/n technologic gap between > usable hf digital and hf ssb, or resolve the bandwidth issues here > in the USA. The other hf digital obstacle is no "wow factor". Hf > digital, so what? Even VHF digital by itself lacks a "wow factor". > Talking to NU5D across town digitally versus fm is no big thrill. On > the other hand, talking to JI1BQW half-way around the world using my > mobile VHF/UHF rig is, so it's not digital voice per se that brings > the "wow factor", it's the gateway interconnect and other features > of DStar such as reflectors that do. On hf none of that is a big > deal. Sure there's a handful of folks who would/will use it, but it > will never catch on.
I definitely agree with John on this one. Digital, by and large, is a big yawn, if all we're doing with it is the same things we've done before. Where it gets interesting in digital is in techniques like WSJT, which aren't nearly fast enough for speech (without being ridiculously broad- banded), but make contacts possible well down into S/N ratios that the human ear can't even "copy". Other benefits of digital include things like D-STAR's ability to cram intelligible (I wouldn't say GOOD quality) speech into less bandwidth than a similar analog single and do it with bits left over for mathematical error correction of weak signals. In the end, it all comes down to bandwidth and what you do with it. "He who dies with the most bandwidth wins!" :-) -- Nate Duehr, WY0X [email protected] facebook.com/denverpilot twitter.com/denverpilot
