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<DIV>Hi Stephen,</DIV>
<DIV> The GPSmart is manually set to WGS84 and the Globalsat is default WGS84</DIV>
<DIV>Both are SIRF powered both give the same amount of error I am wondering if there is an error in the chipset .</DIV>
<DIV> </DIV>
<DIV><A href="http://www.fortuna.com.tw/gpsmart.htm">http://www.fortuna.com.tw/gpsmart.htm</A> GPSmart</DIV>
<DIV> </DIV>
<DIV><A href="http://www.globalsat.com.tw/eng/product_detail_00000044.htm">http://www.globalsat.com.tw/eng/product_detail_00000044.htm</A> Globalsat BU-353</DIV>
<DIV> </DIV>
<DIV>73 Phillip</DIV>
<DIV>ZL2TZE</DIV>
<DIV> </DIV>
<DIV>----------------------------------------------------------------------------------------------------</DIV>
<DIV> </DIV>
<DIV>Message: 14</DIV>
<DIV>Date: Wed, 02 Apr 2008 02:05:47 -0700</DIV>
<DIV>From: "Stephen H. Smith" <<A href="mailto:wa8lmf2@aol.com">wa8lmf2@aol.com</A>></DIV>
<DIV>Subject: Re: [aprssig] GPS off track</DIV>
<DIV>To: TAPR APRS Mailing List <<A href="mailto:aprssig@lists.tapr.org">aprssig@lists.tapr.org</A>></DIV>
<DIV>Message-ID: <<A href="mailto:47F34C6B.9060206@aol.com">47F34C6B.9060206@aol.com</A>></DIV>
<DIV>Content-Type: text/plain; charset=ISO-8859-1; format=flowed</DIV>
<DIV> </DIV>
<DIV>Phillip wrote:</DIV>
<DIV>> Hi,</DIV>
<DIV>> Have am using a Toshiba Laptop Satellite 2140CDS, AGW engine,,</DIV>
<DIV>> UI-View</DIV>
<DIV>> 32, and a DRSI TNC2 as my mobile tracker</DIV>
<DIV>></DIV>
<DIV>> I have 2 New GPS units a GPSmart 12 channel and new today a Globalsat</DIV>
<DIV>> BU-353 SIRF powerd both of them</DIV>
<DIV>></DIV>
<DIV>> Both these GPs give me an error of 55 mtrs East and 30 North in</DIV>
<DIV>> Google when</DIV>
<DIV>> checking with <A href="http://www.aprs.if">www.aprs.if</A> and <A href="http://www.findu.com">www.findu.com</A></DIV>
<DIV>></DIV>
<DIV>> I did a track tonight (02/04/08 NZT) zl2tze-15 with the new BU-353 it</DIV>
<DIV>> has me not packed at my correct address.</DIV>
<DIV>></DIV>
<DIV>> On Saturday ( 29/03/08) I travelled to Nelson using the GPSmart GPS</DIV>
<DIV>> this</DIV>
<DIV>> also has the same error.</DIV>
<DIV>></DIV>
<DIV>> Is this a GPS , UI-View , an error in the Google maps or is it that</DIV>
<DIV>> these</DIV>
<DIV>> cheaper GPS units are not the great ???</DIV>
<DIV>></DIV>
<DIV>> My correct address is zl2tze-4 on the Maps Google</DIV>
<DIV>> Any help on this will be appreciated</DIV>
<DIV>> 73 Phillip</DIV>
<DIV>> ZL2TZE</DIV>
<DIV>></DIV>
<DIV>></DIV>
<DIV>></DIV>
<DIV> </DIV>
<DIV>What datum are the GPS units set for? If they are not set to WGS84</DIV>
<DIV>(WORLD Geodetic System 1984) mode, you will see hundreds of feet error.</DIV>
<DIV> </DIV>
<DIV>This is a constant issue in the U.K. where many paper and electronic</DIV>
<DIV>maps use the British Ordinance Survey datum rather than the WGS84 datum</DIV>
<DIV>that is native and default on most GPS devices. Google Maps (used by</DIV>
<DIV>both findu and aprs.fi) are aligned with the world-wide GPS-inspired</DIV>
<DIV>WGS84 datum. Many British APRS users set their GPS units to use the</DIV>
<DIV>UK ordinance datum to make posits line up on their own maps; only to</DIV>
<DIV>see major errors when they view themselves on Findu or aprs.fi.</DIV>
<DIV>I would guess that Australia and New Zealand may also suffer from this</DIV>
<DIV>problem of a "local" datum in use rather than the world-wide WGS84.</DIV>
<DIV>(The Brits established numerous local datums during the centuries of the</DIV>
<DIV>British Empire in places all over the world.)</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>--</DIV>
<DIV> </DIV>
<DIV>Stephen H. Smith wa8lmf (at) aol.com</DIV>
<DIV>EchoLink Node: 14400 [Think bottom of the 2M band]</DIV>
<DIV>Home Page: <A href="http://wa8lmf.com">http://wa8lmf.com</A> --OR-- <A href="http://wa8lmf.net">http://wa8lmf.net</A></DIV>
<DIV> </DIV>
<DIV>NEW! World Digipeater Map</DIV>
<DIV> <A href="http://wa8lmf.net/APRSmaps">http://wa8lmf.net/APRSmaps</A></DIV>
<DIV> </DIV>
<DIV>JavAPRS Filter Port 14580 Guide</DIV>
<DIV> <A href="http://wa8lmf.net/aprs/JAVaprsFilters.htm">http://wa8lmf.net/aprs/JAVaprsFilters.htm</A></DIV>
<DIV> </DIV>
<DIV>"APRS 101" Explanation of APRS Path Selection & Digipeating</DIV>
<DIV> <A href="http://wa8lmf.net/DigiPaths">http://wa8lmf.net/DigiPaths</A></DIV>
<DIV> </DIV>
<DIV>Updated "Rev H" APRS <A href="http://wa8lmf.net/aprs">http://wa8lmf.net/aprs</A></DIV>
<DIV>Symbols Set for UI-View,</DIV>
<DIV>UIpoint and APRSplus:</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV></TD></TR>
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