At 04:03 PM 5/29/02 -0700, jimlux wrote:
>As a first order approach... use the phased array concept of pattern
>multiplication ... Figure the pattern for two isotropic antennas fed in
>the way you want, then multiply that pattern by the pattern of one
>element. This assumes two identical antennas, of course.. Given that one
>is probably at the top of the tower and one is "next to" the tower, this
>might not be a valid assumption. You might try a simple model with just a
>pair of dipoles (so that you get the polarization and images taken care of).
I'm wondering whether this really works, for stacks at HF, where the ground
is a small number of wavelengths away? It seems to me that identical
antennas are far from it in that environment.
In any case, it is simple enough to model a small stack in NEC/EZNEC and
alter the phasing to see what it produces.
73, Pete N4ZR
Check out the World HF
Contest Station Database at
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