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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I would like to throw out a question. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I use APRS for tracking gliders (sailplanes). From
humble beginnings here in <st1:country-region w:st="on"><st1:place w:st="on">Sweden</st1:place></st1:country-region>,
it has grown into a big success, almost turning a niche sport/event into a
spectator sport. Watching a sport where the track is anywhere from 150 to <st1:metricconverter
ProductID="500 km" w:st="on">500 km</st1:metricconverter> (when will you boys
go metric… ;.) used to be a problem. Now we have some 25 trackers active
in Swedish gliders, and everybody loves it. And, yes, it is perfectly legal,
even when there is no ham onboard. Of course I can’t speak for all
jurisdictions, but at least in <st1:country-region w:st="on"><st1:place w:st="on">Sweden</st1:place></st1:country-region>,
we are OK.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Now to my problem or question. We have tried SmartBeaconing
and fixed interval beacons. Neither one serves a glider particularly well. A
glider (when it leaves to vicinity of the airfield), typically circles in a
thermal to gain altitude and then flies in a straight line to get around the
track. Tests of SmartBeaconing has shown that it is not well suited to this
kind of motion. In fact, it gives the exact opposite of what we want, se below.
Also, to have an exact fix when the glider is <st1:metricconverter
ProductID="200 km" w:st="on">200 km</st1:metricconverter> away is not needed. What
is needed, though is fast updating at the end of the track. Incredible as it
may seem, many competitions end up with the gliders chasing each other within a
few meters (ehh… feet any one…;-) apart in the race to the finish
line. And that is often the case after flying a track of, say <st1:metricconverter
ProductID="300 km" w:st="on">300 km</st1:metricconverter> and 3-4 hours. Speeds
are typically up to <st1:metricconverter ProductID="250 km/h" w:st="on">250
km/h</st1:metricconverter> (mph..?) at the race for the finish line.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>So after this wordy preamble… What I see needed
is some kind of Geofence/box-type beaconing. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>The algorithm being something like:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>If (tracker.lat<N60.5 and tracker.lat >59.8 and
tracker.long<E16.5 and tracker.long>15.9) then beacon every 10 secs<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>If (tracker.distance-to-goal-line < <st1:metricconverter
ProductID="5 km" w:st="on">5 km</st1:metricconverter>) beacon every 2 secs<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'> Else<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Beacon every 3 minutes<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I’m not a programmer (any more), but you are
clever guys, you get my idea. When inside the box (including the starting gate
and finish line) beacon often, outside the box fall back to once every 3 min or
so not to clutter up the QRG. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Does anyone know of some tracker code/application for
this?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Of course, what would also be handy would be a Glider
specific mode:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>If(course .changes. more than 15 seconds) stop
beaconing ./ When entering a thermal and starting to circle /.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>When (course .eq. last.course(15 sec))) beacon ./
When leaving the thermal and flying in a straight line /.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Any one out there doing something like this? <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Thanks for any thoughts and ideas.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>73 de SM0JWX/Rikard<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>(Go metric before <st1:country-region w:st="on"><st1:place
w:st="on">Burma</st1:place></st1:country-region>, please…)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
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