Log Periodic ant
On Tue, 29 Aug 2006 11:27:10 GMT, "Lee"
wrote:
Yes, thanks for the info but i would like a little more gain than a standard
discone gives...going to a parabolic discone would be the alternate option
but a little too involved....
Parabolic discone??!!!?? Involved is not the word.
Hi Lee,
Everyone wants more gain. You don't say why and that may negate
wanting gain.
At the frequency you are desiring, performance is very much limited to
line of sight and even 2M handhelds with rubber duckies can work the
Space Shuttle an hundred miles up.
Consider the downside of gain: you are a tourist at the Grand Canyon
and you put a telephoto lens on your camera (high gain). When you get
home and show your pictures to friends, they might ask why you went to
the Grand Canyon but took pictures only of the river bed at the
bottom, or a cactus on the ridge. Too much gain for the intended use
which was to show the ENTIRE canyon in one shot. This would take a
wide-angle lens (very low gain).
Anyway, simple scaling works. Just research the model of antenna that
gives you the gain characteristics you want, and scale to your band of
interest. The downside here is you may find that you have designed
yourself into a corner because you cannot find the right stock that
supports the dimensions. For a log periodic, this might not matter so
much, and especially for a receiver, but latitude is not generous.
73's
Richard Clark, KB7QHC
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