A recent call for antenna designs for the WA9FOX site reminded me that
there is a large collection of optimized designs available. With one of
the ARRL big books, K6STI contributed his program YA, a sort of read-out
only version of YO. In the collection of antennas were 77 Yagi designs
ranging from 2 elements for 40 meters to 8 elements for 10 meters. The
collection also included 4 HyGain designs. The program carries a 1994
copyright date, so I suspect the distribution was with a 1995 publication.
All the designs are tapered-diameter designs (with untapered dimensions
also given) of rather beefy construction, and all use short, massive
center sections to simulate boom connection plates. Driven element sizes
seem calculated for inherent capacitive reactance. Thus, all of them
might need tweaking for your building specifications.
Nonetheless, this collection is the largest set of Yagi plans of which I
am aware in one place and format. Elements can be reconstructed for
modeling software other than YO/AO with a little patience. Even that
collection only scratches the surface of what is possible with Yagis, but
it is pretty good darn scratch if you want to perfect your modeling
techniques and get an overview of Yagi performance at the same time.
Incidentally to the present topic, although the Swiss Army Knife as a long
European history, it is a relative newcomer to the US compared to another
venerable and durable pocket knife. I am referring to the Boy Scout
knives (of the 1950s, in my case). I still have my 4-blader--it sits in
my shop as THE knife to use at the bench. I shall never chance it to the
tower top or shelf (if I had the latter). It still takes and holds an
edge like no recent knife I have purchased. From a 50' tower, it would go
right through most hard hats. I have never tested it on hard heads.
-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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