[Dstar] RE: Dstar Digest, Vol 13, Issue 6

[Tony Langdon]

At 02:24 PM 9/8/2008, you wrote:

>The data channel in DV is of very limited use as it has no handshaking or
>error recovery. To suggest, as Icom does in their "blurb" ("even the low
>speed data in DSTAR is competitive with packet") is a gross distortion.
>It is in NO WAY competitive with packet as it cannot be used for any serious
>data transfer.

That is changing, with more sophisticated software being written to 
utilise the properties of the data channel.

>Having said that, there are some nice linking features in DSTAR that, in the
>event of a major disaster where normal comms fail will also fail because it
>relies on infrastructure that is likely to be unavailable when government
>emergency services are also struggling.... Once the net is down, so is

Depends on the scale of the emergency and where it is.  Internet 
linked systems have already proven their worth around the world for 
long haul, wide area communications.  And if infrastructure is down 
in the affected area, there is the option of combining it with good 
old HF voice relays and data modes such as PSK-31, to make the final 
hop into the affected area.  HF has the advantage of needing no man 
made infrastructure and easy reliable regional area 
coverage.  However, Internet linked modes (IRLP, Echolink, D-STAR) 
excel at long haul reliable communications.  They reliably work over 
distances that HF has a low probability of working over on a given 
day.  These extreme long haul coverage opens up the possibility of 
running nets in ways never before conceived.

Combine the two and you have the best of both worlds.  I'm not 
talking theory, but experience here.

>linked DSTAR.. However ye olde analogue repeater on top of that hill powered
>by a solar panel will still be going......

So will the D-STAR repeater on the same hill, running on the same 
standby power.  Just that it won't be linked to the rest of the 
world, but it'll still function perfectly well locally as a 
voice/data standalone repeater.

73 de VK3JED
http://vkradio.com