I should have mentioned that those Beverage transformers near the bottom of
http://picasaweb.google.com/katie65752/BeverageAntennas# were made from stacked
FB-73-801 ferrite beads. I used 24 AWG enameled wire. There is no difference in
performance of either Beverage.
I bought some binocular cores with the intention of doing some comparisons with
those transformers. Near the bottom end of the AM broadcast band, it seems that
the directional properties might be off; KTWO AM 560, ENE about 45 miles away
in
Springfield, MO seems to be a tad stronger on the SW direction. It works just
fine on 160, but with another transformer I used in the past, KWTO seemed to be
strongest to the NE.
I used galvanized electric fence wire, and calculated the diameter (.061") vs.
spacing (1.1") so that the feedline impedance was equal to the impedance
between
the feedline and ground at 10' high. If you construct your Beverage so that
those two impedances are significantly different, then you should use a
reflection transformer other than a 1:1 as I did.
73,
Mike Waters
www.w0btu.com
________________________________
From: Kenneth Grimm <grimm@sbc.edu>
To: topband@contesting.com
Sent: Sat, November 20, 2010 1:23:47 PM
Subject: Topband: 2 wire beverage question
Has anyone built a two wire beverage simply fed with two lengths of RG-6
instead of the usual switching arrangement in the feed end box? The
arrangement appears in most of the literature since the earliest days, but I
don't think I've ever heard of anyone doing it that way. At this stage
however, I've got more RG-6 than I have inclination to build a switch box,
bias T, etc, plus the fact that I already have a switch box in the shack to
take the two coaxes. Advice appreciated.
73,
Ken - K4XL
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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