[TowerTalk] Positoners Calibration to True North

[Jim Lux]

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