Re: Different location on APRSIS32 and APRS.fi


ae5pl <pete@...>
 

I just looked at the packet in jFindu which matches APRSIS32's position report. The Mic-E packet content that jFindu is working from is:

VK2JNG-12>S5QLZL,VK1RGI-1*,WIDE2-2,qAR,VK1KCM-5:'M4l K&#92;]146.950MHz G'Day to all APRS users.=

The character after the M4 is a 0x1c and the character before the K is a 0x1c. A space separates the 1 and 0x1c before the K.

findU.com computed the position as -35.18333 149.39999 which is 35 10.10S 149 24.00E The differences here could be rounding issues.

I am guessing that aprs.fi is not handling something quite right in its algorithm for Mic-E interpretation.

73,

Pete AE5PL

--- In aprsisce@yahoogroups.com, "Lynn W. Deffenbaugh" <kj4erj@...> wrote:

aprs.fi has 35 15.00S 149 25.00E
aprsis32 has 35 10.00S 149 24.00E

That's a pretty big (and visible) difference, I agree. Now, we can only
assume that the 710 is correct because it's got the GPS.

aprs.fi has one of your 710 packets as:
2010-03-09 11:24:19 UTC:
VK2JNG-12>S5QLZL,VK1RGI-1*,WIDE2-2,qAR,VK1KCM-5:'M4<0x1c>l
<0x1c>K&#92;]146.950MHz G'Day to all APRS users.=

or

*2010-03-09 11:24:19 UTC VK2JNG-12
<http://aprs.fi/?c=raw&limit=&view=hex&call=VK2JNG-12>: 95 bytes*
0x00 V K 2 J N G - 1 2 > S 5 Q L Z L , V K 1 R G I - 1 * , W I D E 2
564b324a4e472d31323e5335514c5a4c2c564b315247492d312a2c5749444532
0x20 - 2 , q A R , V K 1 K C M - 5 : ' M 4 1cl 1cK &#92; ] 1 4 6 . 9 5
2d322c7141522c564b314b434d2d353a274d341c6c201c4b5c5d3134362e3935
0x40 0 M H z G ' D a y t o a l l A P R S u s e r s . =
304d487a2020472744617920746f20616c6c20415052532075736572732e3d

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