+TheElliottClan2012 Posted August 22, 2012 Posted August 22, 2012 Hello All! We (The Elliott Clan 2012) have just started out in the world of Geocaching and are loving every minute of it! However today we got our GPS device. A basic Garmin Etrex (the old yellow version with a black globe symbol on the front). I got the hang of its use very quick and typed in several coordinates for some caches. Thing is i knew exactly where the caches were yet the GPS was over 100ft out!?! (no tree cover either!) Is the GPS set up wrong? Can i re calibrate it or something else? Please help as this is getting annoying and we are struggling to find caches! Thanks Paul (The Elliott Clan 2012) Quote
RuideAlmeida Posted August 22, 2012 Posted August 22, 2012 Welcome! Sure you can recalibrate your device, no harm done. Most of the times that difference is related to a incorrect datum in the GPSr. WGS84 is the default standard datum for coordinates stored in recreational and commercial GPS units, but for any reason you may have changed it... please check it out. Quote
jholly Posted August 22, 2012 Posted August 22, 2012 Hello All! We (The Elliott Clan 2012) have just started out in the world of Geocaching and are loving every minute of it! However today we got our GPS device. A basic Garmin Etrex (the old yellow version with a black globe symbol on the front). I got the hang of its use very quick and typed in several coordinates for some caches. Thing is i knew exactly where the caches were yet the GPS was over 100ft out!?! (no tree cover either!) Is the GPS set up wrong? Can i re calibrate it or something else? Please help as this is getting annoying and we are struggling to find caches! Thanks Paul (The Elliott Clan 2012) Make sure it is set to WGS-84. (Setup->units->datum) Quote
+TheElliottClan2012 Posted August 22, 2012 Author Posted August 22, 2012 Thanks both! Have it set to that but it still seems off? How do i recalibrate? Paul Quote
+The Blorenges Posted August 22, 2012 Posted August 22, 2012 If it's a very basic model I don't think you can recalibrate them. Did it come with a manual? If not, have a look at this link which may help: Garmin Etrex Owners Manual MrsB Quote
+Bear and Ragged Posted August 22, 2012 Posted August 22, 2012 Delete any coordinates you have loaded. Reset to the correct settings. Reload the coordinates. (The unit may be converting the coordinates as you change the settings, so may never be 'correct'!) Quote
+GeoTrekker26 Posted August 22, 2012 Posted August 22, 2012 Thanks both! Have it set to that but it still seems off? How do i recalibrate? Paul You cannot calibrate a GPS. If the GPS is equipped with an electronic compass, the compass can and needs to be calibrated however most GPSs, including yours, do not have an electronic compass. Note that an electronic compass is just that, an electronic version of an old fashioned pocket compass; it does not rely on the GPS signals to point north. It is unfortunate and confusing that the term "compass" is used for both the pocket compass substitute and the navigation screen used on almost all GPS units. Why do you think your GPS is off? Under normal circumstances it should get you within 30-45 feet of the published coordinates which themselves are subject to the same error. In a rather old, but undated webpage, Garmin claims an average accuracy of 15 meters. Yes, there are times the GPS will get right on the target but those times should be considered lucky. Also one of the advantages of the newer units is that they tend to be more accurate. That said, your yellow eTrex is a fine GPS to begin with. If you really like the hobby and want to continue with it you will probably want to move up to a paperless GPS, but that can wait for some time! Enjoy your caching! Quote
+TheElliottClan2012 Posted August 22, 2012 Author Posted August 22, 2012 Thanks! I think you may be on to something here.....????.....i checked the coordinates after changing the datum and they are all slightly out even though i double checked all of them first time round! I will pop back out tomorrow morning and try again with updated coos! Delete any coordinates you have loaded. Reset to the correct settings. Reload the coordinates. (The unit may be converting the coordinates as you change the settings, so may never be 'correct'!) Quote
jholly Posted August 22, 2012 Posted August 22, 2012 Thanks! I think you may be on to something here.....????.....i checked the coordinates after changing the datum and they are all slightly out even though i double checked all of them first time round! I will pop back out tomorrow morning and try again with updated coos! Makes perfect sense. The coordinates you had were with the old datum and when changed the datum it recalculated the coordinates in the new datum and changed the coordinates for the same point. And as has been pointed out, outside the electronic compass there is no calibration. The GPS works on mathematical calculations, if those are off your sunk. Quote
+TheElliottClan2012 Posted August 27, 2012 Author Posted August 27, 2012 All sorted now! 40 caches down in 4 days! I'm officially hooked! Anyone know of any good walk in GEO shops in the north east (UK)? Cheers Paul TEC2012 Quote
+The Blorenges Posted August 27, 2012 Posted August 27, 2012 All sorted now! 40 caches down in 4 days! I'm officially hooked! Anyone know of any good walk in GEO shops in the north east (UK)? Cheers Paul TEC2012 GeoTees have an online site and also a Real Life shop. Details of location and opening times here: GeoTees shop, Halifax, UK MrsB Quote
+TheElliottClan2012 Posted August 28, 2012 Author Posted August 28, 2012 Thanks! Looking for a bit further north though around Durham / Newcastle over to Middlesborough / Sunderland...... Cheers Though! Quote
+The Blorenges Posted August 28, 2012 Posted August 28, 2012 Thanks! Looking for a bit further north though around Durham / Newcastle over to Middlesborough / Sunderland...... Cheers Though! I think GeoTees has the only walk-in geocaching supplies shop in UK. There used to be one run by UK Geocachers but that has closed quite recently. MrsB Quote
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