[TowerTalk] compass question

[Jim Lux]

>Date: Mon, 10 Feb 2003 16:49:06 -0800
>To: "RICHARD BOYD" <ke3q at msn.com>
>From: Jim Lux <jimlux at earthlink.net>
>Subject: Re: [TowerTalk] compass question
>
>Everybody has a different conceptual picture of how to remember this, so 
>try a variety of mnemonic devices until you find one that works.
>
>Depends if you are west or east of the Agonic Line (i.e. the line on which 
>the deviation = 0).. In your case, you are east of the line, so the 
>deviation is west.. (that is, the direction to Mag north is to the left 
>(west) of the direction to true north).  So, for you, when the needle 
>points to 350, the zero points to true north.
>
>If you remember that the mag north pole is up near Hudson's Bay (70N, 
>100W, approx), and mentally think about where that is, vs where the "real 
>north pole" is, you can figure it out.
>
>Also, US topographical maps have this indicated, pictorially, at the bottom.
>
>If you have one of those nifty azimuthal equidistant projection maps 
>centered on your QTH, you can find True and Mag north poles and just hold 
>your compass over the map.
>
>For those who live in the far East(80E longitude),or in the Southern 
>Hemisphere, you'll need other conceptual aids...
>
>There are some nice pictures at: 
>http://academic.brooklyn.cuny.edu/geology/leveson/core/linksa/magnetic.html
>
>
>Jim, W6RMK
>
>
>At 06:57 PM 2/10/2003 -0500, you wrote:
>>No, this is not the perennial finding true north question.  In my area, 
>>Maryland, the "magnetic deviation" is about 10 degrees.  I can never 
>>remember, though, if that means when I have my compass out I should let 
>>the needle come to a stop on 350 or on 10 to have zero pointing at true 
>>north.  Magnetic north is where the needle will point, obviously, and 
>>true north is 10 degrees off from that, but I can never remember which 
>>way.  ?  73 - Rich, KE3Q