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Old July 31st 07, 08:45 PM posted to rec.radio.amateur.antenna
Michael Coslo Michael Coslo is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 828
Default Wants to poke out strong signal

You wrote:
In article ,
Roy Lewallen wrote:

An antenna radiates at all elevation angles. It does not "put out" at
any single angle. Likewise, it receives signals from all elevation
angles, not just a single one.

Roy Lewallen, W7EL


Roy, You know better than to make the above "Statement". It is way to
"General" in nature. Certainlky there are a whole raft of "Antennas"
that have both Horozontal and Vertical Beamwidths, that are NOT
Omnidirectional. The OP didn't specify the Frequency at which the
"antenna" was being used at, and the "Higher" the frequency the more
likely the antenna will NOT be OmniDirectional, and will have Horozontal
and Vertical Beamwidths.......



I tend to agree with Roy. Omni or not, Every antenna radiates in every
direction. Maybe not as much in one as the other, but radiate they do.

So many folks look at the Take off angle as some sort of blob that
leaps off the antenna at a particular angle, and if it isn't at that
"correct" angle, then heaven help you i you are trying to operate NVIS
or DX or whatever.

Some time back, at Roy's suggestion, I conducted some experiments with
my dipole and vertical antennas to see which one "worked best". Using a
attenuation pad, it really wasn't as trivial as I thought it would be.
But I learned a lot. Dipole at the time was an OCF, and vertical was a
Butternut HF6V.

What I did learn was that at any given moment, either the vertical or
the horizontal antenna was "the best". While some generalizations could
be made for distance and the angle the signal was likely coming in at,
there was a lot of variation within it. The difference could vary over
time also.

That being the case, I questioned if assuming that the angle for best
reception is also the angle for best transmission, especially with what
appears to be a change over time.

- 73 de Mike KB3EIA -