Hi,
For finding true north, Someone passed this to me and it was very useful.
Sorry if it has already been posted recently.
Just go to:
http://aa.usno.navy.mil/ <http://aa.usno.navy.mil/>
Click on "Data Services" and then click on:
"altitude and azimuth of the sun or moon during one day"
Then use the form provided to get a chart of the azimuth of the sun for any
given day and location. NOTE: the default
"tabular range" is set for 10 minutes but you can change that for a much
longer or shorter table. You won't see much
difference in 10 minutes so that setting worked for me. NOTICE: The chart
it produces is Central Standard Time (in my case -
don't know if that changes to your own time zone so I had to calculate for
the fact we are in daylight savings time)
Then just take it out in by your tower when the sun is out and check out the
shadow cast by your tower and see if your beam
is lined up correctly. Just subtract 360 degrees from the sun azimuth and
that should give you the true direction for the heading of
the shadow.
For example, for my location now the sun is at 137 degrees so my shadow on
my tower should be pointing at: 223 degrees
(137 degrees east of north - 360 degrees). I could set my beam on 223
degrees and go out and see how it matches up with
the shadow.
(If I were at home dxing instead of here at work on my lunch time !!)
Gary Stone, N5PHT
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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