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<font color="#000066"><small><big><big><small>I have been building a
standalone APRS iGate, using an Omnima
embedded
controller with OpenWrt (Linux) and running Aprx 2.0
(<a class="moz-txt-link-freetext" href="http://wiki.ham.fi/Aprx.en">http://wiki.ham.fi/Aprx.en</a>). This has been up
and running for about a week and everything looked to be working just
fine (see M0RXW-B on aprs.fi).<br>
<br>
However, yesterday afternoon I had a call from (M0NAS) that he was
seeing very strange movements on aprs.fi. Now
interestingly, when he called he was still seeing strange position
reports coming through, but I had powered off the iGate almost 2 hours
earlier at 14:27 UTC (15:27 local). <br>
<br>
Looking at the raw packets for M0NAS-9 on aprs.fi I see:</small>
<br>
<br>
</big></big></small><span class="raw_line">2010-09-04 16:01:10 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0NAS-9">M0NAS-9</a></b>>UR0QW2,WIDE1-1*,WIDE3-2,qAR,<a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a>:`v?Dns1>/"4Y}Neil mobile</span><br>
<span class="raw_line">2010-09-04 16:20:16 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0NAS-9">M0NAS-9</a></b>>UR0RV3,WIDE1-1*,<a
href="http://aprs.fi/?c=raw&limit=&call=G1DHB">G1DHB*</a>,WIDE3*,qAR,<a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a>:`vA5n56>/"4`}Neil mobile</span><br>
<span class="raw_line">2010-09-04 16:40:21 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0NAS-9">M0NAS-9</a></b>>UQ5YT4,WIDE1*,WIDE3*,qAR,<a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a>:`vI nSJ>/"45}Neil mobile</span><br>
<span class="raw_line">2010-09-04 16:43:51 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0NAS-9">M0NAS-9</a></b>>UQ5YQ3,WIDE1*,WIDE3-1,qAR,<a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a>:`vG|n@,>/"4F}Neil mobile</span><br>
<span class="raw_line">2010-09-04 16:54:30 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0NAS-9">M0NAS-9</a></b>>CQ,WIDE1-1*,WIDE3-2,qAR,<a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a>:>Neil mobile</span><br>
<span class="raw_line">2010-09-04 16:55:37 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0NAS-9">M0NAS-9</a></b>>UQ5VU2,WIDE1-1*,WIDE3-1,qAR,<a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a>:`vD@mK3>/"4S}Neil mobile<br>
<br>
And looking at the raw packets from my iGate M0RXW-B on aprs.fi I see:<br>
<br>
</span><span class="raw_line">2010-09-04 16:59:28 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a></b>>RXTLM-1,TCPIP*,qAC,T2ITALY:T#626,31.3,0.0,127.0,108.0,0.0,00000000</span><br>
<span class="raw_line">2010-09-04 17:00:22 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a></b>>APRX20,TCPIP*,qAC,T2ITALY:!5110.89NR00018.64E&Rx-only iGate (aprx2/OpenWrt 10.03 - <a
class="moz-txt-link-abbreviated" href="mailto:row@hopgarden.net">row@hopgarden.net</a>)</span><br>
</font>
<span class="raw_line"><font color="#000066">2010-09-04 17:01:26 UTC: <b><a
href="http://aprs.fi/?c=raw&limit=&call=M0RXW-B">M0RXW-B</a></b>>RXTLM-1,TCPIP*,qAC,T2ITALY::M0RXW-B :PARM.Avg 10m,Avg 10m,RxPkts,IGateDropRx,TxPkts<br>
<br>
This doesn't make any sense to me as my iGate was physically powered
off at 14:27 UTC whilst I was reflashing the device. Some how packets
continued to be retransmitted for about 3 hours after the device was
powered off. This would explain the strange tracks on APRS if the
packets were being replayed out of order.<br>
<br>
I've since been speaking with the operator of MB7UUE
(<a class="moz-txt-link-abbreviated" href="mailto:g3rji.alanpaul@gmail.com">g3rji.alanpaul@gmail.com</a> - <a class="moz-txt-link-freetext" href="http://2e0avq.co.uk/">http://2e0avq.co.uk/</a>) which is a new
bidirectional gateway, that is bridging from the Internet to RF and he
is also not sure what might be causing this.<br>
<br>
Is it possible that MB7UUE could have somehow created a loop in the
system? i.e. RF->Internet->RF->Internet.<br>
<br>
Reuben<br>
</font></span>
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