> ========== Over "average" ground the pattern would be slightly oval
> with a "F/B ratio" of about 1.33 dB. Directivity favors the same
> direction that the radials run.
In an effort to bring a pattern into spec, an engineer cut and
removed radials in the null area of the towers at WAAM radio in
Michigan, a location with fairly good farmland.
The only measurable thing (using normal BC FS measurements)
that happened was the entire pattern became a little weaker, and
the system became unstable with moisture.
An identical result occurred in the 70's at a station licensed to
serve Bowling Green, Ohio (WMGS?) where someone did the
same thing!
It is very possible that a 1 dB change in directivity would be
missed, but the decrease in field strength in the desired direction
and instability of the arrays were definitely noticeable.
73, Tom W8JI
W8JI@contesting.com
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