On 21st July, George wrote:
"...You should have longer (and more) radials as moving up the current
maxima up moves the return current maxima away from the base of the
antenna..."
*********************************
...So, by making an "extended" T antenna---much as Stew Perry made an
extended 170' "L" antenna---one effectively moves the current maxima up from
the base (Let me play devil's advocate at this point, as I'm trying to grasp
the theory of such a set-up here in my own plans to convert a 3-element "L"
array, to a 3-element "T" array.).
Do I assume correctly that the builder does this by lengthing the flat top
portion of the "T"...? And if that is, indeed, the case, then:
(1) Can one go "overboard" to the point of having the current maxima at the
top of the "T", vs. the vertical portion (i.e. enhancing horizontally
polarized radiation, vs. vertical polarization?);
(2) And if that's so, then won't there be a cancellation of this horizontal
component of the antenna's radiation by virtue of the inherent
design/advantages of having a "T"...? and finally,
(3) Is the end result of all this then little more than an extended wire
dummy load, in terms of radiating effectiveness...?
I'm intrigued with the possibilities of using my inverted "L" elements just
as they are, but halving the horizontal flat top portions of each, and
forming the existing wire into a "T". I like the idea of being able to
resonate each individual element by way of the series tuned variable
capacitor at the element bases, and hope to carry this on with a new
3-element "T" array...
I also like the notion that the horizontally-polarized radiating element of
the antenna is negated in a "T" as well...but in light of all my conflicting
thoughts, I'm wondering if an "...extended T" (like W1BB's extended "L") is
even possible...?
BTW, I'm musing aloud like this without benefit of the latest issue of QEX
before me: the local Ham emporium unfortunately does not carry it, so I'm at
a disadvantage with others who may have already read & digested the piece
that's in there...
~73~ Eddy VE3CUI - VE3XZ
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