Re: Worth sending back to Garmin to "repair"?


"Len Philpot" <len@xxxxxxxxxxx> wrote in message
news:1gcxt107xu7y2$.1vt5ny220lynq$.dlg@xxxxxxxxxxxxx
On Sat, 27 Jan 2007 08:46:39 -0500, Bruce wrote:

I wonder if "level" is in reference to the magnetic dip. I think it must
be
since the GPSR probably doens't have any sensor to figure out if it is
level
as referenced to gravity. So perhaps the OP is at a high latitiude and
the
GPSR needs to be held at an angle to the ground so that it is level with
the
dip. 20 or 30 degrees of course sounds extreme.

I'm in Louisiana (N31 20.864 W92 21.262), so "high latitude" (nor "high
altitude", for that matter :-) doesn't apply to me.

I'm going to try to play with it outside today, but not until the rain
stops. I wasn't near anything when I was testing it last night in the
house, but then again there /might/ be interference of some kind
(wiring, etc.). I don't know just how sensitive the compass is to that
kind of thing.

I've wondered how it knows to prompt for level. I assumed there was some
kind of sensor, but maybe not?
--

---- Len Philpot -------- l e n @ p h i l p o t . o r g (no spaces)
------- ><> ------------- http://pages.suddenlink.net/lenphilpot/

I did some experiments with my GPSMAP 60CS and it does appear that it is
important to keep the GPSR level to the earth while calibrating the compass.
I guess it takes into account the dip while calibrating. I calibrated it
while holding it well away from level and then I got "hold level" while
using it even though I had it level. I also tried calibrating it when there
was a local magnetic field (a steel cookie ***) and it also gave me "hold
level" while using it. So it looks like the calibration needs to be done
well away from any local magnetic fields and held level to the earth as best
as possible.


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