Re: garmin rebate


Dale DePriest wrote:
miso@xxxxxxxxx wrote:

Here is my issue. When you hike steep or rugged terrain, i.e. a path
where you can't make decent forward progress, a virtual compass is
pretty worthless since the differential readings (perhaps sequential
is a better word) are not far enough apart. I'd like the compass not
to be fussy. It really wouldn't have to be all the accurate for hiking,
but I've seen the Garmin compass in action on older models and it just
won't do.

while your concerned is well founded it is not based on how the GPS
actually computes direction. It is not done with sequential readings but
is computed from the Doppler shift from the satellite data. Only one
reading is needed but there has to be a velocity component that is not
zero or nearly zero.

Dale


Get general GPS information at:
http://www.gpsinformation.net/

Your website doesn't seem to agree with you:

http://www.gpsinformation.net/main/gpsbearing.htm
"The GPS computes it's bearing to the next waypoint based on knowing
the coordinates of the target AND the GPS receiver's current location.
(Assuming the target is a km or more away, the bearing will normally
be very accurate indeed. This is true if or not the GPS is in motion or
at rest.) HOWEVER, the GPS computes it's DIRECTION OF TRAVEL (as
opposed to bearing to the next waypoint) by computing its position at
approximately 1 second intervals and calculating DIRECTION OF
MOVEMENT."




--
_ _ Dale DePriest
/`) _ // http://users.cwnet.com/dalede
o/_/ (_(_X_(` For GPS and GPS/PDAs

.

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