Vicki Powys wrote:
> I'm now using a GPS unit (the most basic Magellan unit available from RAOU)
> for atlassing. I've tried it out around home for "not getting lost" and
> I've found I really need to use a magnetic compass in conjunction with the
> GPS unit, to find direction accurately. Is this what other people do?
> Perhaps there are more precise units than mine?
The direction shown on GPS units is really direction of travel,
and is calculated by comparing two or more consecutive coordinate
readings. If you aren't moving, or don't move far enough to
register a difference in coordinate readings, the direction
indicated is more or less random. This affects all GPS units
other than those with a magnetic compass built-in (e.g. Silva
Multi-Navigator.)
> To find North via my GPS, I need first to take a reading, then proceed at a
> fast gallop for 20-30 metres before the corrected north arrow shows up on
> the GPS screen, and fast gallops are not possible on mountain tops, or in
> scrub. Hence the compass. Any other ideas?
Most GPS units let you mark waypoints, and will give you a
bearing and distance to the waypoint from your current position.
Some will also give you the bearing and distance between two
waypoints. If you mark your starting point then walk a reasonable
distance, say 50m, you should get a reliable bearing to the
starting point even while standing still.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Paul Taylor Veni, vidi, tici -
I came, I saw, I ticked.
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