> "This is why wide broadcast towers, even 1/2 wave tall towers, can have
>reasonably low impedances at the base.²
Agreed. I have found it very difficult to model accurate complex base Z
measurements of wide broadcast towers (i.e., low height/diam. ratio) that
are of the 180-195 degree variety - even with NEC4.2. This is one of
NEC¹s more significant limitations.
In some of these cases, lighting systems and any STL transmission lines
play a part in the true base Z. Still, I routinely get results that show
much higher base Z in the model than actual measured base Z results.
Paul, W9AC
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