Im getting to grips with my new etrex 20 and making waypoints for it.
I was looking in to the GPX format and there does not seem to be anything that specifies which map datum you are using, eg. WGS84 or OSGB36.
For example: Kingshouse in Glen coe would be
How does the etrex (or any gps device) know what format the lon/lat uses? I know that the etrex can change the settings on the device to display grid refs/different coordinate systems but surely this should be specific to the gpx files espcially if you have loaded multiple gpx files using different systems?
Thanks - would appreciate any thoughts on this!
Hm, I am also not fully sure about the datum to use. I often write the values shown in Google Earth down and then create such WayPoints in a GPX file to be transferred to my Oregon - and it works correctly! You can also set the symbol, e.g.