[TowerTalk] Using an iPhone App to line up your antenna

[john at kk9a.com]

Can you use this compass in the woods or do trees attenuate the earths 
magnetic field?


To: towertalk at contesting.com
Subject: Re: [TowerTalk] Using an iPhone App to line up your antenna
From: Jim Lux <jimlux at earthlink.net>
Date: Wed, 04 Jan 2012 15:45:10 -0800

3G doesn't have magnetic sensors
3GS does

There are compass apps for 3G that use GPS and velocity to infer heading.