At 10:29 AM 4/19/2010, john_ke5c wrote:
> Nothing that would prevent you from making and scoring points using DV
> Simplex.
If anyone seriously plans on using VHF simplex DStar during Field Day, a
simplex frequency other than 146.520 might be agree upon? Perhaps 146.580?
First, the rules for all ARRL contests and Field Day prohibit using 146.52
for making contacts.
As for 146.58, well, here's something to keep in mind to avoid having
D-STAR get a really bad reputation among analog simplex users:
Stay off the analog simplex channels!
It's a courtesy thing, not a rules thing (other than that amorphous "good
amateur practice" deal). On an analog receiver, a D-STAR signal sounds like
"open squelch," a fairly loud rushing sound. So it is pretty much
impossible to share a simplex channel between analog and digital users. The
D-STAR users won't have a problem. They'll hear either nothing (auto-detect
turned off), or they may hear the analog signal normally (auto-detect
turned on). The analog users can do nothing to prevent hearing the D-STAR
Woooosh, short of leaving the frequency. And that will make them very
unhappy indeed.
This is worse than mixing it up among repeaters, where tone access can at
least mitigate the problem some. We can't expect all simplex users to begin
using tone encode/decode to avoid hearing our D-STAR signals.
The solution: separate spectrum. In much of the country, the spectrum
between 145.5 and 145.8 is already "digital," albeit for packet. 145.67 has
been informally adopted for D-STAR simplex in areas where there is no
incumbent packet system.
So for Field Day, I suggest 145.67 unless you have packet activity in your
area. Attention Minnesota! 145.67 is used for a statewide packet system.
73,
Gary KN4AQ
ARVN: Amateur Radio//Video News
Gary Pearce KN4AQ
508 Spencer Crest Ct.
Cary, NC 27513
<mailto:[email protected]>[email protected]
919-380-9944
www.ARVideoNews.com
