[Loadstone] Direction change

Robert (Jamie) Munro rjmunro at arjam.net
Sun Dec 14 01:19:57 GMT 2008


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Kerry and Gemma Hoath wrote:
>
> [lots of correct stuff about GPS and direction]
>
> It would be well to remember you are using a series of satelites in 
> geostationary orbit to track your location; 

Minor point this, but a common misunderstanding:

The satellites are not in geostationary orbit - they are much closer to
the earth than that, and they do not follow the equator, they are in 6
rings 60 degrees apart around the equator at an angle of 55 degrees from
the equator. There's a great explanation and animation here:
http://en.wikipedia.org/wiki/Global_Positioning_System#System_detail

If you switch on WAAS or EGNOS on your reciever, you use signals from a
single additional satellite which is in geostationary orbit.

> and not a differential source.
> If you had a ground-based differential source and the ability to use it; 
> you'd be able to potentially get far more responsive direction information.

I'm not sure what you mean by "differential source" and why GPS
satellites don't count as one. Do you mean directional?

I've heard that some GPS units include a magnetic compass which can tell
which way the unit is pointing without it moving. If you want fast
updates of which direction you are facing, it may be worth investing in
one of those, but I'm not sure if loadstone supports them.

Robert (Jamie) Munro
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEARECAAYFAklEXzsACgkQz+aYVHdncI043gCg5RiaS8jZz8CD2QBqX67GJ2yP
9MIAnRSIMH6c8ULyzKa6sBFTF+sdLePB
=7lQx
-----END PGP SIGNATURE-----


More information about the Loadstone mailing list