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Old August 10th 09, 06:07 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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Default Antenna pattern fro a summit

On Mon, 10 Aug 2009 05:19:41 -0700 (PDT), ve2pid
wrote:

Hi to all,


All too high.

NEC gives the pattern for an antenna mounted at a certain height above
an infinite flat ground.

But suppose that we are on a mountain top (summit) with a relatively
steep grade. Does the pattern changes, i,e. is the TO angle going
lower above an horizontal line coming from the antenna?

If so, is there a kind of 'correcting factor' giving the modified
height applicable?


See:
http://www.cplus.org/rmw/english1.html
Locate the antenna exactly on the terrain model (SRTM2) and you'll get
the real antenna pattern. You can input the actual antenna pattern
into Radio-Mobile for better accuracy instead of using generic omni,
cardioid, yagi, etc patterns.

Bad examples (but all I have online):
http://802.11junk.com/jeffl/coverage/kg6nri/



--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558