In case you have ever wondered what the pattern of a traditional all-band
135' doublet looks like across the ham bands, I have just placed patterns
(AZ and EL) modeled at 35 and 50 feet up for 80-10 meters, along with ball
park 450-ohm and 300-ohm transmission line data for a half wavelength
(which, of course, repeats), at the web site. Look under Antennas from
the Ground Up at the end of the listing, and then look at #5 in that
series. Purpose: to create reasonable expectations of such an antenna.
In case you have never wondered what these patterns look like, do not peek
at the site under any circumstances and go on believing that some sellers
of some off-center-fed antennas have worked magic when they claim a
beam-like 10 dBi off of their wires and never, ever believe that hams have
been getting this gain since the earliest days of upper HF work.
Well, ok, peek anyway.
-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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