A number of folks have asked me from time to time for copies of the model
3-element Yagis I use for comparative purposes. I have put them at my
site (under the title "Three Element Yagis: Standards of Comparison") in
the form of antenna descriptions from EZNEC. Since they are simple
models, putting them into any of the modeling programs is 15 minutes work
for all 3.
Remember that 1. they are not chromed; 2. they are not polished; 3 they
are not even real antennas in a sense. They use only one diameter of
tubing so that the models are small, run quickly, and serve as checks
against which to measure other experimental designs. Why, they are not
even absolutely optimised, but only approximately so for a balance of
gain, F-B, and SWR operating bandwidth. But they are pretty good as
standards of what you can get out of 1/3 wl boom length and useful for
many purposes. The words in the posting are a lot of cautions about not
using them wrongly, but put in the affirmative on how to use them rightly.
The original from which all 3 models are adapted came from a sample with
AO5 by K6STI.
If you want to think about building any of them, be sure to adjust the
design for your materials. Single diameter model elements and stepped
diameter model elements do not play the same.
Hope the data is useful to someone.
-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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