Ed, you wrote;
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"You are correct about top loading a folded unipole. The Uni-Hat CTSVR
uses a large top hat for loading a folded unipole. The skirt system is
also used to match the feed line to the antenna using three series
capacitors to achieve a 50 ohm match on each of the four bands of
operation instead of traps. This design methodology is the basis for the
claims in the patent I received last year for the CTSVR. 73, Ed Goodman
- N5NUG"
I have the CTSVR brochure here. Unfortunately, both the brochure and the
CQ Magazine review of the CTSVR contain erroneous and misleading
statements, in my opinion. The vertical is only about 31 feet high. Yet,
the following claim is made on the front page:
"Inverted radiation pattern with the maximum current point situated 30'
above ground level. This produces a high radiation resistance (50 Ohms)
and highly efficient low loss radiator in a short structure twenty two
degrees electrical length on 160 Meters."
Sorry, there is no way that a 31 foot vertical on 160 M works out
enjoying a 50 ohm radiation resistance!! The old folded element feed
myth for increasing radiation resistance is once again perpetuated here.
Obviously, the feedpoint Z is stepped up by the folded element to 50
ohms, a la transformer action, but NOT the radiation resistance. CQ
magazine reviewer went right along with this misconception, saying that
because the radiation resistance is a high 50 ohms, the antenna does
well with a simple ground system (my memory of the essence of the
statement).
Otherwise, I'm sure it's as good an antenna as a 31 footer can be on top
band.
73, Roy K6XK Iowa
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