Woah.... hold on here...
John, W0UN, wrote:
>Actually it is a little more complex than all of this (isn't life like that)
>because of the changes in mutual coupling, etc. But for a first
>approximation (read guess) you can spray two directions knowing that 1/2
>your power is going in a second direction and that power is having little
>effect on the half that is going in the first direction.
John and co. - I think you have the essentials correct - especially
the first part of the above statement and the rest of your posting.
But I would not take even as a zero-th approximation the second part
of the above statement. Consider this: First, unless the "stacked"
antennae are many wavelengths apart each will ALWAYS be in the near
field of the other. Therefor, you can never consider the pair (or
mulltiplet) as sepreate antennae. You must evaluate the sum total of
amplitude and phase of the radiation patterns, which will be very
different than the scalar sum of the patterns that would sugest that
you can spray two dirrections equally. This is basic physics, and is
the way it is. Secondly, as you point out, some arbitrary point a
very long ways off doesn't "know" there are two antennae at a given
QTH. This only underscores my first point.
I have not modeled this specifically, but think how the wakes of two boats
moving in different directions interact on the watter - especially when
they are just within several boat lengths from each other.
Just my two cents worth - for what it's worth...
cheers, Chuck Claver, PhD.
de NJ6D
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