Art Unwin wrote:
"When modeling close spaced element antenna assemblies it is possible
that some elements are physically longer than the "driven" element. Is
the length of an element sufficient to declare a "reflector" or are
there other caveats involved (i.e. phase)?"
Art answered his own question. The element doesn`t care how it gets a
leading (capacitive) current, or a lagging (inductive) current.
In our broadcast curtain antenna arrays, we used an RCA WM-30A phase
monitor for the current angle in the ibnductive parasitic reflectors.
Phase was adjusted to spec with a short-circuit stub connected to where
the feedpoint would be if it were a driven element.
Kraus is unequivocal on page 245 of edition no. 3 of "Antennas":
"When the halfwave parasitic element is inductive (longer than its
resonant length) it acts as a reflector. When it is capacitive (shorter
than its resonant length) it acts as a director."
Best regards, Richard Harrison, KB5WZI
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