[TowerTalk] Compass and GPS

[Doug Ronald]

I should have excerpted all of K8RI's post, particularly this:

 

> My Garmin Vista H has electronic compass separate

> from GPS. (not all Garmin do) so it has some kind of

> magnetic sensors.

> I know I can turn it on and off separately, to save battery power.

 

Because the option to turn it on or off is programmed, it pretty much has to
be a power hungry flux gate type.

 

There are MEMS devices with 20 nW power consumption which the manufacturer
wouldn't bother to power down. With <= 0.3 mT field sensitivity, one can
make a handy compass out of one of them.

 

-Doug Ronald (AE6SY)