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Hi Frank:
The patented MC-1G Global compass works at any latitude and would
point to a local pole.
While on a polar flight between washington state and London I found that
a magnetic compass was useless for some time when we were near the North
pole and even the MC-1G would have a problem when too close to a pole.
One thought I have had is to combine a 3-D magnetic field sensor and a
3-D accelerometer and in static situations you could determine the
difference between down and the magnetic filed and compare that to the
World Magnetic Model. This result would probably be only a few spots on
the Earth where you might be, but during a reversal if there were
multiple poles, then you could only navigate within one poles region.
Have Fun,
Brooke Clarke, N6GCE
http://www.PRC68.com
Frank Reed wrote:
> Brooke C wrote:
> "I'm not sure what yo mean by "regions of high field inclination"."
>
> Regions close to the magnetic poles where the field lines are nearly
> vertical. If you have a multipolar field, like the sort of field you
> might have during a polarity reversal, then you will have a number of
> poles scattered around the globe possibly in places that would be
> inconvenient.
>
> Since you certainly seem to know your sensors (I enjoyed your web page
> very much), in this "what-if" scenario where the field becomes
> multipolar, could one design a magnetic compass that would yield
> useful directional information (like standard compass bearing) even
> very close to a magnetic pole? If you had to cross an ocean where a
> magnetic pole is right in the middle of your trackline, could you have
> a compass that would yield useful information all the way across?
>
> Frank R
> [ ] Mystic, Connecticut
> [X] Chicago, Illinois
