Hi All,
I guess I'm just plain stupid, or something, because I still can't seem to
be able to wrap my head around this one...!
One of the advantages of the "T" antenna---vs. the inverted "L"---is that
horizontally polarized/high angle radiation is supposed to be cancelled by
virtue of the opposing tee tops...correct?
So---by lengthening the tee tops, we are---as has been stated here
before---moving the current peak up the antenna, away from the base, and
toward the tee...still correct?
And if THAT'S still so, aren't we then creating an ineffective antenna, by
virtue of the facts that:
(A) It's useless as a DX antenna because the vertically-polarized low-angle
current node has moved UP the vertical portion, becoming more high-angled
and horizontally-polarized, and,
(2) It's even useless as a close-in "cloud warmer" because the opposing
horizontal components of the tee inherently cancel any radiation from this
part of the aerial.
It seems to me there's a lot more to all this business than is immediately
apparent. What holds as a truism in the one instance---i.e. when the "T"
antenna is resonant---surely must apply, as well, when the system is
deliberately lengthened...or so I would think.
The texts all seem to be somewhat nebulaous in this matter of the top-loaded
Marconi/"T" antenna...maybe that's the basic problem: there aren't any
immediate "hard and fast" formulas that one might readily apply to the
design & construction of these things...there seems to be a LOT of "cut and
try" in the execution of the top-loaded "T" antenna.
The more I think about it all, the more I'm inclined to leave my array as it
originally was, i.e. a system of inverted "L" elements...!
~73~ Eddy VE3CUI - VE3XZ
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