[TowerTalk] Compass and GPS

[Jim Lux]

On 1/4/12 7:03 PM, Doug Ronald wrote:
> 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.
>

That's probably the iPad/iPhone/Android widget category...