Calculating the difference between magnetic north and true north is one
way.
Here is another way. Go here and enter your QTH cordinates.
http://aa.usno.navy.mil/data/docs/AltAz.html
For the day you are going to make the measurement, get the time of day
when the suns azmuith is 180 degrees, which should put it due south of
you. (For VK land maybe you need zero degrees, which would put it due
north.) You need a vertical object that is really vertical, sight the
shadow of this object at the time given. This will be true north (or
maybe true south for VK).
Us guys in the south USA also have another way of determining ture
north. You can find lots of references in the archives.
I wonder if it works in VK land.
Jerry, K4SAV
VK2SN - Sean P Neylon wrote:
>Dear all,
>
>
>
>I am just about to stand up my tower with everything ready to go.yippee..at
>last..
>
>
>
>I have Azimuth and Elevation Positioners M2 OR2800PDC and M2 MT1000 see
>www.vk2sn.com <http://www.vk2sn.com/> for further details of my set-up.
>
>
>
>My location is in the city of Sydney Australia S33 53' 12.6'' and
>E151 14' 45.4'' Grid QF56oc
>
>
>
>To start with I will calibrate my poisoners to True North for Nova and
>such., then once up and running, I will use the Sun or whatever to further
>calibrate via the controller for accuracy. But I want to at least get it
>close to accurate before I put the tower up.
>
>
>
>I also cant really re-adjust once it goes up, I have to pull it down and so
>on.its very heavy for one person, so Im hoping to get things sorted before
>it goes up,..plus its too dangerous to climb and Im not one for climbing
>towers..I like my kids and want to see them live for a very long time.I
>don't have the experience.smile.I'll do most things in life..but not climb
>towers on houses..!!!
>
>
>
>So the question is, I will use a compass to choose North, but this is
>Magnetic North, to get True North, how many degrees do I add or subtract
>from Magnetic North.or where can I find this info, or how can I calculate it
>from my Sydney position - because I gather its different for everyone re
>Latitude.
>
>
>
>By the way, I hope this makes sense, the last time I had to figure out where
>I was by using a compass was when I was about 14 years old..so I would like
>some advice..
>
>
>
>Please advise if Im doing this right, or is there a much better and easy way
>to sort/calibrate this situation..
>
>
>
>Thanks guys,
>
>
>Sean Neylon
>
>
>
>
>
>
>
>Sean P. Neylon VK2SN QF56oc
>
>Cell Phone: ++ 61 413 747 276
>
>web: www.vk2sn.com
>
>email: sean@vk2sn.com
>
>
>
>_______________________________________________
>
>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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