Hi Jim,
Unfortunately there's no free lunch. The slope of the "gull wing" elevated
radials shortens the effective height of the vertical radiator. To achieve
resonance, the length of the vertical must be lengthened by almost the length
of the gull wing slope.
The 1/4 verticals in my 4-square array originally used "gull wing" elevated
radials. The radials started at ground level, sloping at 45 degree angle to 8
feet above the ground. The radials were cut to resonant length (X=0) by
connecting them in pairs to an MFJ-259.
I had to shorten each vertical by about six feet when I replaced the elevated
radials with sixty 120 foot radials for each vertical, laid on the surface of
the earth.
Active 160 meters contesters and DXers can tell you how much the performance of
the 4-square array improved when we replaced the elevated radials.
73
Frank
W3LPL
---- Original message ----
>Date: Wed, 1 Aug 2012 09:07:25 -0700 (PDT)
>From: Jim Hoge <knowkode@verizon.net>
>Subject: Re: Topband: FCP model
>To: topband reflector <topband@contesting.com>
>
>Team Vertical has employed a gull wing style of raised radials that would
>eliminate your concerns. I'm not the expert here.... just mentioning another
>alternative.
>
>Jim W5QM
>
>
>
>________________________________
>
>
><For a short vertical I prefer ground radials over an elevated counterpoise
>because the counterpoise height reduces the monopole length.>
>_______________________________________________
>UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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