After I posted the expansion of the "Driven Element-Director" item, to add
a combination DE-Ref for 17/DE-Dir for 12 to the 17/12 m back-to-back
DE-Dir design, I had a couple of inquiries about combining either of the
two with a 30-meter dipole.
So I did: back-to-back DE-Dir Yagis for 17 and 12 with a 30-m dipole.
The dipole is now the feedpoint for everything, and coax matches all. It
is not perhaps the zenith of tweaking, but it will get experimenters
started. The dipole is centered to place its mass closest to the mast
line, but due to difference is the boom requirements on the 12 and 17
sides--and slight weight differentials, the dipole will be off-centered
just about anough to mount on the boom. However, you could mount it on
the mast itself and position the 2-Yagi boom for best coupling.
Hope the expanded notes are 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://web.utk.edu/~cebik/radio.html
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