I think this may have been pointed out already but the altitude reported by the T'bolt is the WGS84 altitude, which is not at all the same as the altitude on your USGS map.
If you look up WGS84 in wikipedia you will find a better explanation of that than I could ever give. Some of the gps control programs will give both altitudes, but Tboltmon does not. GPSLog does both I think... In my case the real ASL altitude of my antenna is about 50 metres; the T'bolt says about 12, which is fine by me. So long as it is happy :^) dr _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
