Hi Fellows,
> Read the description carefully. On the C39, the 40 DE is BETWEEN the
> 15 DE and the 15 reflector, NOT behind the 15 reflector.
>
> They HAVE had to deal with removing the 21 mhz resonance from the 40
> "N" elements. The diagram is at home, but the distance from the 40 DE
> to the 15 DE on the same boom is a LOT less than the vertical mast
> separation the original poster proposed between the separate antennas.
>
This seems to be going in circles.
Has anyone modeled this or measured it?
It is important to stress that even without resonance a large
structure in the nearfield can affect performance greatly. We all
deal with that every day, but when it comes to antennas we seem
to toss it all out and assume if it isn't resonant it can't affect the
system.
I know for sure it will affect the smaller antenna, the question is
only if it is enough to worry about. Do any of you know the answer
with some convincing evidence?
73, Tom W8JI
w8ji@contesting.com
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