This seems like a real good link for study of just the
compass thing you asked about:
http://www.scoutingresources.org.uk/compass_magvar.html
73 fer nw,
Bob AD5VJ
10X# 37210, FP#-1141, SMIRK#-5177
http://www.n5iet.com/
Code may be taking a back seat for now,
but the pioneering spirit that put the code
there in the first place is out front of it all.
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of
Jim Lux
> Sent: Thursday, December 01, 2005 10:54 PM
> To: Tom McAlee; towertalk@contesting.com
> Subject: Re: [TowerTalk] Positoners Calibration to True
North
>
>
> At 08:15 PM 12/1/2005, Tom McAlee wrote:
> >Since the original question was posted by a VK station,
it might be
> >worth noting that using Polaris to locate north can
only be
> done in the
> >northern hemisphere. It is not visible below the
equator.
> >
> >Down there you'll need to locate south and flip that
180.
> But, there
> >is no "south star" such that the south end of the
earth's
> axis points
> >almost directly at it. But, there is some bizarre
combination of
> >constellations/stars and drawing lines and following
them
> >perpendicularly to other stars, etc., that can be used
to locate the
> >south pole with enough accuracy for antenna work.
> >
> >But, never having been in the southern hemisphere, I
don't know the
> >details. I'm sure you can find info about it on the web
though.
> >
> >And, by the way, Polaris isn't exactly north; it's
about 1
> degree off
> >true north.
>
>
> use the SUN.. at local solar noon, the shadow will
either be
> directly north
> or directly south. The trick is figuring out when local
> solar noon is.
> Fortunately, you probably don't need to know to the
gnat's
> eyelash second
> of arc accuracy.
> Noon is when the shadow is shortest, but if you mark
where
> the shadow is
> equal lengths, the north south line is exactly halfway
between.
>
> Jim
>
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
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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