I had never been completely satisfied with the models used to obtain
anticipated results from the HB9CV design of a phased 2-element horizontal
array. since the original posting, I have developed some further tests of
model adequacy, including relevant cross checks between NEC and MININEC,
among other things.
The results has been some downward revision of the figures one may expect
from an HB9CV design with reasonable F-B. These figures exceed what is
possible from a parasitical 2-element beam, but fail to seriously
challenge the 7 dBi free space mark. I also have an electronic dust bin
filled with more optimistic models that failed various modeling tests.
Only the HB9CV section of the overall HB9CV note is affected. I am
working on a simple way to convert almost any 2-element Yagi into a
modified ZL/HB configuration for additional F-B with just a couple of
hunks of coax and a fixed capacitor.
More on that later. I hope the revised HB9CV notes present a more
accurate picture of a basically good antenna.
-73-
LB, W4RNL
L. B. Cebik, W4RNL /\ /\ * / / / (Off)(423) 974-7215
1434 High Mesa Drive / \/ \/\ ----/\--- (Hm) (423) 938-6335
Knoxville, Tennessee /\ \ \ \ / / || / (FAX)(423) 974-3509
37938-4443 USA / \ \ \ \ || cebik@utk.edu
URL: http://funnelweb.utcc.utk.edu/~cebik/radio.html
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