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Re: Topband: Waller Flag six month update. The rotatable RXantennat that

To: "'Bill Dawson'" <>
Subject: Re: Topband: Waller Flag six month update. The rotatable RXantennat that really works on 160 / 80 m
From: "n4is" <>
Date: Sat, 19 May 2007 08:09:41 -0400
List-post: <>
Hi Bill

Well, the Waller Flag, as I called it, is not a new antenna project, the
idea of it started with WA2WVL articles QST Feb, 1995, "Is this EWE for
you?" At the end of the second article, Floyd mentioned the new design of a
dual EWE in end-fire, but no constructions or practical evaluations details.

Few years later, Earl K6SE QST July 2000, working with EA3VY come up with an
improved project ground independent Low Band Receiving Antenna and Earl K6SE
called it a Flag Antenna.  Earl also presented the project of two flags in
phase with a nice diagram. ON4UN also mentioned the project idea on his

So the Waller Flag is just two flag's antennas phased 180 degree.

Three years ago Doug Waller, NX4D living on 1/3 city lot put a goal to work
as many DXCC on low bands as possible from his limited size lot. First he
built a rotatable flag and started to improve the project, Doug figured out
the possibility to build two small flags in end fire configuration. He
followed most of Earl's recommendations on his article.

Remove common mode currents is mandatory. You don want to receive signals
form you feed line shield. We use RF chokes of 15 turns of RG174 on
FT-140-77 or FT-279-77 core. 
First it was necessary to detune my tower because I learned it in the hard
way, since I got my vertical full size, my EWE's just stopped  working, I
just lost they, before with my vertical at 85ft the EWE's always received
better then my vertical. 

I chose to transform my shunt feed vertical into a SKIRTED UNIPOLE and using
a detuning relay disconnecting the Skirt from the tune circuit I was able to
recover the reception on my Ewes. The Skirt works like a ¼ wave coax
transformer, it is grounded on the top of the antenna and open at the
bottom, so it has high impedance at the base. The skirt tunes at the exactly
at ¼ wave with a small 37 pF doorknob capacitor.

With my TX antenna properly detuned the noise level on my EWE's dropped 2 S
units just. The full size vertical was reradiating all that noise into my
receiver antenna.

The RDF of the Dual Waller Flag antenna is 11.6 db, depending is you tune it
for max RDF it can reach 11.8 db, tuning for best Front/Back the RDF drops
to 11 db. I'm using 180 phasing line and R1=750ohms and R2=766 ohms. The
EZENEC Azimuth diagram is very close to 1.75 wave beverage and the
measurements I'm taking shows a 76 degree 3db angle. The beverage elevation
lob angle peaks at 40 degree and the Waller Flag peaks at 20 degree. The
diagram is very close to a well built 4 SQ receiving array but it peaks at 8
degree on good ground.

The Waller Flag is ground independent and can be installed on top of any
tower, even at 200 ft high if you want.



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