To: <towertalk@contesting.com>
>Date: Mon, 10 Feb 2003 16:49:06 -0800
>To: "RICHARD BOYD" <ke3q@msn.com>
>From: Jim Lux <jimlux@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
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