>
>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
I've done lots and lots of modeling with AO of 5 el stacks with yagi's
pointed in different directions and, as long as they are pointed in distinctly
different directions, so that their front lobes are not crossed, there is
essentially no interaction worth talking about. Again, we are talking
PRACTICAL and not 20 db down!
Because the C3 is only 2 elements, this interaction might be more s
substantial because it isnt going to have the tighter pattern of even a 3 el.
monobander. I really dont understand why you would want to rotate a whole
stack of C3's separately but that's up to you.
73, Tyler
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