[TowerTalk] True North

[Robert Isby, Jr.]

On Dec-2, I read where someone was directing a person to purchase a book.
In the Geodetic Surveying world, this is called Magnetic Declination

Go to this web page and enter the data.  Zip Code is sufficient as declination really does not shift 
much across a state, unless you are in California

http://www.ngdc.noaa.gov/seg/geomag/jsp/Declination.jsp

Cheers.
Robert Isby, Jr. [N2LUD]