<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<div class="moz-signature"><br>
</div>
<div class="moz-cite-prefix">On 11/7/2020 7:35 PM, Eric H.
Christensen via aprssig wrote:<br>
</div>
<blockquote type="cite"
cite="mid:W989PZcu1JtE-DntXAA5s-pQKxByTL4jY2SdFUJi_O8z3lVAMGOMNj9Q4OXVFHAMaVeXcnGEPIC7VeZWi9MYcDpbw-6UR5QXcAT9pSpsTMA=@aehe.us">
<pre class="moz-quote-pre" wrap="">I think I just found a flaw in APRSIS32 (but it may not be limited to that software).
</pre>
</blockquote>
<p>It's not a flaw, it's a feature.</p>
<blockquote type="cite"
cite="mid:W989PZcu1JtE-DntXAA5s-pQKxByTL4jY2SdFUJi_O8z3lVAMGOMNj9Q4OXVFHAMaVeXcnGEPIC7VeZWi9MYcDpbw-6UR5QXcAT9pSpsTMA=@aehe.us">
<pre class="moz-quote-pre" wrap="">I've been seeing stations slide across my screen over the past few weeks. I couldn't quite put my finger on it until tonight. Here's what I'm seeing:</pre>
</blockquote>
<p>It's helpful if you supply specific examples so that we can
adequately research the details. Especially what software you are
using that shows "stations slide across my screen".<br>
</p>
<br>
<blockquote type="cite"
cite="mid:W989PZcu1JtE-DntXAA5s-pQKxByTL4jY2SdFUJi_O8z3lVAMGOMNj9Q4OXVFHAMaVeXcnGEPIC7VeZWi9MYcDpbw-6UR5QXcAT9pSpsTMA=@aehe.us">
<pre class="moz-quote-pre" wrap="">A non-mobile station will suddenly relocate itself a distance away only to move back to where it came from a short time later. After working with one station, and looking at the packets being sent directly to the IS, I noticed two things: 1) the position reports are not changing, and 2) the status reports (of which I've never found to be useful) contain a properly formatted status report *with Maidenhead Grid Locator*.</pre>
</blockquote>
<p>If a station is reporting two different locations with different
precision and/or different center locations, then yes, some
software will display them ping-ponging between the two
locations. APRSISCE/32 remembers the most precise coordinate
received and will ignore the less precise coordinate (typically
the grid square) to avoid this issue.</p>
<br>
<blockquote type="cite"
cite="mid:W989PZcu1JtE-DntXAA5s-pQKxByTL4jY2SdFUJi_O8z3lVAMGOMNj9Q4OXVFHAMaVeXcnGEPIC7VeZWi9MYcDpbw-6UR5QXcAT9pSpsTMA=@aehe.us">
<pre class="moz-quote-pre" wrap="">So, what I think is happening is my client is seeing the position report and plotting the station as expected. It is then seeing the grid locator in the status text and moving the station to the middle of the grid, as it should per the APRS spec[0].</pre>
</blockquote>
<p>Again, I'd be curious as to what client you are running. The
author of that client might be able to implement the same approach
that APRSIS32 uses.<br>
</p>
<br>
<blockquote type="cite"
cite="mid:W989PZcu1JtE-DntXAA5s-pQKxByTL4jY2SdFUJi_O8z3lVAMGOMNj9Q4OXVFHAMaVeXcnGEPIC7VeZWi9MYcDpbw-6UR5QXcAT9pSpsTMA=@aehe.us">
<pre class="moz-quote-pre" wrap="">
Having never run APRSIS32, I'm wondering if this is a setting somewhere in the software to include the grid in the status text. I've seen so many of these stations sliding across my screen it would seem to be odd that it is an individual effort.</pre>
</blockquote>
<p>It is a mis-configuration by the operator who doesn't understand
the effects s/he is causing in other clients. Yes, there is a
checkbox in the status configuration of APRSIS32 that includes the
GridSquare in the status report. But status reports are not
enabled by default, nor is this box checked by default. The
option is there for someone that doesn't want to beacon positions
but only do Status Reports with GridSquare included. Anyone that
enables both, again, doesn't understand what they are doing.</p>
<p>So, if you want the station to stop doing that, contact the
operator and educate them. Tell them that they are beaconing two
different positions and to disable one or the other. They can
keep the Status Report, but just don't include the GridSquare
within it. And point them to the wiki page</p>
<p><a class="moz-txt-link-freetext" href="http://aprsisce.wikidot.com/menu:configure-status-report">http://aprsisce.wikidot.com/menu:configure-status-report</a></p>
<p>that even says:</p>
<p>
<blockquote type="cite"><strong style="color: rgb(0, 0, 0);
font-family: verdana, arial, helvetica, sans-serif; font-size:
12px; font-style: normal; font-variant-ligatures: normal;
font-variant-caps: normal; letter-spacing: normal; orphans: 2;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 2; word-spacing: 0px;
-webkit-text-stroke-width: 0px; background-color: rgb(221,
221, 238); text-decoration-style: initial;
text-decoration-color: initial;">GridSquare</strong><span
style="color: rgb(0, 0, 0); font-family: verdana, arial,
helvetica, sans-serif; font-size: 12px; font-style: normal;
font-variant-ligatures: normal; font-variant-caps: normal;
font-weight: 400; letter-spacing: normal; orphans: 2;
text-align: left; text-indent: 0px; text-transform: none;
white-space: normal; widows: 2; word-spacing: 0px;
-webkit-text-stroke-width: 0px; background-color: rgb(221,
221, 238); text-decoration-style: initial;
text-decoration-color: initial; display: inline !important;
float: none;"><span> </span>- If checked, the current
GridSquare will be included in the Status Report. Use this
with caution if you are also transmitting position beacons as
the position resolution between the GridSquare and Lat/Lon
coordinates is significantly different, possibly resulting in
a station that ping-pongs between two locations depending on
which packet was heard most recently.</span></blockquote>
</p>
<p>Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and
Win32
</p>
<blockquote type="cite"
cite="mid:W989PZcu1JtE-DntXAA5s-pQKxByTL4jY2SdFUJi_O8z3lVAMGOMNj9Q4OXVFHAMaVeXcnGEPIC7VeZWi9MYcDpbw-6UR5QXcAT9pSpsTMA=@aehe.us">
<pre class="moz-quote-pre" wrap="">
73,
Eric WG3K
[0] <a class="moz-txt-link-freetext" href="http://www.aprs.org/doc/APRS101.PDF">http://www.aprs.org/doc/APRS101.PDF</a> (pages 8, 27, and 81-82)
_______________________________________________
aprssig mailing list
<a class="moz-txt-link-abbreviated" href="mailto:aprssig@lists.tapr.org">aprssig@lists.tapr.org</a>
<a class="moz-txt-link-freetext" href="http://lists.tapr.org/mailman/listinfo/aprssig_lists.tapr.org">http://lists.tapr.org/mailman/listinfo/aprssig_lists.tapr.org</a>
</pre>
</blockquote>
<p><br>
</p>
</body>
</html>