<html>
<head>
<meta content="text/html; charset=windows-1252"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
Peter,<br>
<br>
APRS is different things to different folk.<br>
<br>
Some see its original purpose, position reporting, as the priority.<br>
<br>
Others followed Bob's thinking that here was a packet passing
network that could be utilised for all manner of purposes.<br>
<br>
The fundamental tension between these two is that position reporting
is degraded as channel utilisation increases, and use for other
purposes degrades position reporting.<br>
<br>
I have studied the causes of packet loss (meaning packets that were
transmitted that did not find their way accurately to APRS-IS) and
the causes are many fold, and most of the root causes result in high
channel utilisation which is the indirect cause of most packet loss.<br>
<br>
In the beginning, there were digis as a means of sharing position
data over a wider geography.<br>
<br>
Then came iGates which provide a superior method of sharing position
data.<br>
<br>
In this area (I live just SW of Sydney), all prominent digis are
captured by two or more iGates, so you might question the need to
shuffle packets along through three digis... but it is done and it
is a major cause of congestion.<br>
<br>
If you have a reliable iGate on a prominent site, it can be argued
that it should not digipeat at all because it only raises congestion
without improving packet flow to APRS-IS.<br>
<br>
Indeed, repeating the packet only risks sub standard iGates
submitting corrupted packets (there are something like 10 such digis
that get hold of my packets and corrupt them).<br>
<br>
I have been in conversation with the author of Microsat about
smarter filtering capabilities for digis, and he understands the
case for filters that drop packets on hop count, or that have passed
through digis in a drop list... but it is not yet implemented. For
the most part, the digi network cannot do intelligent routing...
Bob's "New N Paradigm" of a decade ago was a mid life kicker for
APRS that is not up to the current need.<br>
<br>
If you have access to a prominent site and have affordable Internet
access, I suggest you install the node as iGate ONLY, and that you
configure it to use pre/de emphasis in tx/rx as was originally
intended.<br>
<br>
Be very cautious about iGating ANY IS to RF. The channel utilsation
during busy hour halved here when a ham who was iGating his buddies
to RF three digi hops away flooded the channel with unwanted
traffic.<br>
<br>
Not everyone will agree with this approach I am sure... so ask
around.<br>
<br>
Owen<br>
<br>
<br>
<div class="moz-cite-prefix">On 19/10/2014 8:50, VK3AJ wrote:<br>
</div>
<blockquote
cite="mid:002301cfeb1d$8b4c5c10$a1e51430$@chaplin.net.au"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=windows-1252">
<meta name="Generator" content="Microsoft Word 15 (filtered
medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Wingdings;
panose-1:5 0 0 0 0 0 0 0 0 0;}
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
<div class="WordSection1">
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Greetings to all on this list,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I manage a number of radio sites here in
Victoria for Scouts Victoria as well as myself in significant
locations.<o:p></o:p></p>
<p class="MsoNormal">Since getting a nice new TM-D710GA to play
with, I have been getting more interested in APRS and how it
works.<o:p></o:p></p>
<p class="MsoNormal">I noticed some significant holes in the
APRS coverage in the areas my voice repeaters cover, so have
started the process of establishing APRS on one of the sites
(VK3RSA) to fill these holes and learn more about how the
network works.<o:p></o:p></p>
<p class="MsoNormal">I’ve tried contacting our Victorian APRS
coordinator to no avail, so are seeking advice from members of
this list on the right way to set it up, how best to configure
it for best performance and not have an adverse effect on the
APRS network.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The site has excellent free high speed
internet access, so I am interested in setting it up as an
iGATE as well.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So to specifics.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The hardware is a Microsat WIN3in1 mini
connected to a 25W Motorola MCS2000 mobile into a Folded
Dipole antenna on a water tower 48m AGL.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The site is a high mountain that has 360deg
visual coverage for 100+ Km in 85% of horizon. Nearest
obstructive mountain is the Dandenong ranges 15Km away.<o:p></o:p></p>
<p class="MsoNormal">Current tests from the site shows
significant coverage improvements across the area.<o:p></o:p></p>
<p class="MsoNormal">Some of the information I have read on the
internet (so it must be true <span
style="font-family:Wingdings">J</span>) suggests that APRS
sites on high mountains aren’t necessarily a good option. Is
this correct?<o:p></o:p></p>
<p class="MsoNormal">The site shows a path from my mobile
(VK3AJ-9) as SW55Q7 via VK3RSA-1, WIDE*,WIDE2-1,qAR,VK3GY-1.
I’m note 100 percent sure what all this means, but have
noticed that other sites show WIDE1-1 where mine shows WIDE*.
What effect does this have?<o:p></o:p></p>
<p class="MsoNormal">Can anyone advise the correct settings for
a WIN3in1 mini in such an environment?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">How do I go about setting it up as an
iGATE? Is this an appropriate option?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have three other sites that I could add
APRS to depending on appropriateness. 1 is in a rural area not
currently covered by APRS (SW corner of Victoria) and the
other 2 are outer eastern Victoria sites. How do I get / Who
is best to advise me on suitability of these sites for adding
to the network?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m a hands on learner, so please, no
highly technical answers.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance for the collective
wisdom.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<i><o:p></o:p></i></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><i><span
style="color:green;mso-fareast-language:EN-AU">Peter
Chaplin</span></i></b><span
style="color:#1F497D;mso-fareast-language:EN-AU"><o:p></o:p></span></p>
<p class="MsoNormal"><span
style="color:green;mso-fareast-language:EN-AU"><a
moz-do-not-send="true" href="mailto:peter@chaplin.net.au"><b><i><span
style="color:blue">peter@chaplin.net.au</span></i></b></a></span><span
style="color:#1F497D;mso-fareast-language:EN-AU"><o:p></o:p></span></p>
<p class="MsoNormal"><b><i><span
style="color:green;mso-fareast-language:EN-AU">VK3AJ<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span
style="color:green;mso-fareast-language:EN-AU">Scout
Radio & Electronics Service Unit<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span
style="color:green;mso-fareast-language:EN-AU">Repeater
Coordinator<o:p></o:p></span></i></b></p>
<p class="MsoNormal"><b><i><span
style="color:green;mso-fareast-language:EN-AU">0418 328
882</span></i></b><span
style="color:#1F497D;mso-fareast-language:EN-AU"><o:p></o:p></span></p>
<p class="MsoNormal"><i><span
style="font-size:7.5pt;color:#1F497D;mso-fareast-language:EN-AU"
lang="EN-GB"><o:p> </o:p></span></i></p>
<p class="MsoNormal"><i><span
style="color:red;mso-fareast-language:EN-AU" lang="EN-GB">No
trees were harmed in the posting of this message...however
an extraordinarily large number of electrons were horribly
inconvenienced.</span></i><span
style="color:red;mso-fareast-language:EN-AU"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
OZAPRS mailing list
<a class="moz-txt-link-abbreviated" href="mailto:OZAPRS@aprs.net.au">OZAPRS@aprs.net.au</a>
<a class="moz-txt-link-freetext" href="http://lists.aprs.net.au/mailman/listinfo/ozaprs">http://lists.aprs.net.au/mailman/listinfo/ozaprs</a>
</pre>
</blockquote>
</body>
</html>