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Old March 2nd 07, 12:12 AM posted to rec.radio.amateur.antenna
[email protected] nm5k@wt.net is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 757
Default Effect of raising vertical antenna higher

On Mar 1, 9:12 am, Buck wrote:
However, Steppir antennas says
that an antenna on the ground needs 120 radials just to match one in
the air with two radials.


That would only apply to an elevated antenna 1/2 wave or higher up
though..

I would like to know where the noticable
benefit of raising an antenna above the ground actually takes place
and where is the maximum benefit.

I know that the higher the better, but rather than that kind of
benefit, I am wondering from a ground standpoint where the benefits
start and where the point of diminishing returns begins.


Just depends on the band, the path/angle used most of the time, the
ground quality, etc, etc.. Raising it to 40 ft from 12 feet would make
a
noticable difference if you compare all the various types of paths.
IE:
Just the local ground/space wave will be improved a good bit.
As far as the ionosphere, would effect farther off stations more,
than closer in. It's possible for the low antenna to be nearly as
good on a short/medium hops, but DX will be better on the higher
antenna and possibly open/close the band a bit earlier/later.
Ground loss will be lower, but I'm not sure it's worth the cost of
the
cherry picker.. I'd tend to say not, being a cherry picker is usually
not cheap.. Being the current antenna is just a bit less than a 1/4
wave up, it's not in near a bad a shape as say a 80 or 40 antenna
at that height in feet.
MK