I received quite a few replys with questions on EWEs, so here are my
answers/comments re:EWEs.
Thje EWE antenna name is a cute way of saying "U" (upside down). The
EWE, of course, was the logo used in Floyd's (WA2WVL) article in Feb 1995
QST.
The design I am using on all five of my EWEs is the dual band design in
Floyd's article. A close look at the several designs he presents will
show that the patterns/gains, etc of this design are superior (in my
opinion) than those mentioned for single band. The design I use is: 15
ft verticals connected by a 38 ft horizontal wire. The verticals are
connected to a load resistor of 830 OHMs (10 OHMs smaller than that
suggested in the article 'cuz that's what Radio Shack had!) at the
receiving end and to a K2ZJ (ZJ Electronics) Beverage Box at the driven
end. All antennas are fed with RG-58 cable. Both verticals use 4 ft
copper ground rods with liberal application of Jet-Lube copper lubricant.
The two phased EWEs are separate EWEs, 130 ft apart (in the same plane,
so that an areial view of them would depict a rectangle with the corners
at the locations of the four verticals. They are fed with equal lengths
of RG-58, using a non-amplified K2ZJ Beverage Box and connected together
at the common point and impedance-matched with a 2:1 Minicircuits
transformer (model T2-2). The single feedline to the shack is RG-58 as
well. Total feed line length from shack to Minicircuits xformer = approx
100 ft. Length of equal-length feedlines to each EWE is 175 ft. I used
the unamplified box in this application because I suspected that the 10dB
gain in the ZJ box, if used, would swamp the T2-2 xformer. I have
noticed that the 10 dB gain in the box is really not necessary anyway.
I have used a Slinky Beverage made from 8 slinkys (total length = 50 ft).
The EWE always outperforms the slinky.
I mount 3.5 of my EWEs on the wooden fence line in my back yard. One of
the EWEs is suspended by two trees, 1/2 of another is in the trees. The
trees do not seem to affect performence.
BTW, the K2ZJ boxes attach directly to a 5/8 inch ground rod making them
very convenient. Check out the ZJ Electronics homepage, available from
the PVRC home page and elsewhere.
Glad to answer more Qs if any.
73!
Bill, N3RR@EROLS.COM
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