[TowerTalk] Strange behavior

[Jim Brown]

On Sun,1/22/2017 7:15 PM, Roger (K8RI) on TT wrote:
> If I'm not mistaken the smart phones derive the compass from GPS

Not all -- many phones have sensors for position and orientation 
separate from GPS. That's how, for example, they know when to rotate the 
image when you rotate the device.

> which is true, not magnetic so it wouldn't require a correction.

For GPS to determine azimuth the observer must be moving. That works 
fine in a vehicle, but not when you're walking.  Ask me how I know. :)

73, Jim K9YC