In article <[email hidden]>, Chris Malcolm "]<URL:[email hidden]>
wrote: [snip]
Quoted message said:
A useful trick for getting an accurate waypoint in a spot of bad reception, when there are nearby
spots of good reception, is to stand for a few minutes in the spot of good reception (or until all
grey sat reception bars have gone black), and then walk to the spot of poor reception, still
carrying some of the accuracy acquired with you. This can even be used to set good waypoints in
places of no reception, if you walk into the area of no reception at a constant speed and in a
straight line, because most units allow a period of grace before abandoning tracking when they
assume you're just carrying with the same direction and speed. With the Garmin units I'm familiar
with this period of dead reckoning grace is 30 seconds.This usually gives better results than averaging in a place of poor reception, since poor
reception due to poor skyview usually has a biassed skyview and thus biassed error spread.
That's a very useful feature I hadn't thought to make use of in the way you describe.
Mike <URL:http://www.path.cam.ac.uk/~mrc7/>
--
o/ \\ // |\ ,_ o Mike Clark <\__,\\ // __o | \ / /\, "A mountain climbing, cycling, skiing, "> ||
_`\<,_ |__\ \> | immunology lecturer, antibody engineer and ` || (_)/ (_) | \corn computer user"