[Antennas] Using GeoClock To Find True North

Tue, 19 Feb 2002 05:31:22 -0600

Just a thought
As the sun "rises" between 9 and 10, the 10 o'clock shadow will be lower
and back in the E/W plane, maybe?

Jim, N5QL 

-----Original Message-----
From: Don Havlicek [mailto:[email protected]] 
Sent: Monday, February 18, 2002 5:17 PM
To: Jim Clark
Cc: [email protected]
Subject: Re: [Antennas] Using GeoClock To Find True North

No, no, no .... if the two marks were made at 0900 and 1000, then N/S
line would be somewhere close to NW/SE !!!!!

Better to do this:  
1.  Drive the stick into the ground and mark the end of its shadow at
some time in the early morning, recording the clocktime.
2.  Mark the the end of its shadow again at a time which is the SAME
AMOUNT AFTER noon that the first mark is BEFORE noon.
3.  Now do what you suggest:  the perpendicular bisector of the segment
between the two points is APPROXIMATELY the N/S line.
4.  Better way:  Use the North Star as someone previously mentioned.
5.  Best way:  Use a compass and apply the correct declination
correction.
Don
N8DE

Jim Clark wrote:
> 
> This sounds like a job for Indiana Jones or Laura Croft. (I'll take
> Laura!)
> 
> Egyptian compass:
> 
> Pick a nice sunny day.
> Drive a stick several feet long into the ground straight up.
> Mark the end of its shadow with a small stick.
> 
> About an hour or so later mark the shadow's position again.
> Draw a line between these two points.
> A line perpendicular to that line is north / south.
> 
> Jim, N5QL
> 
> 
> 
> - - -
> 
> Your moderator for this list is:
> Larry Wilson KE1HZ [email protected]
> _______________________________________________
> Antennas mailing list
> [email protected]
> http://mailman.qth.net/mailman/listinfo/antennas