The only lunch is in the ground if you want to heat worms Frank, at least in
this area.
With high conductivity ground then the radials might not need elevating. On
a rock pile elevating beats laying down an an acre or more of copper.
I didnt bother resonating them and just cut to 130' and hauled thru the
trees and the vertical resonance didnt change between 4 and 32 but the R
went down as did the bandwidth somewhere between 16-32. At such a low
elevation I dont believe resonating makes any difference when ground losses
are so high. At 1/4 wave elevated then its a true GP and resonating is
important.
Carl
KM1H
----- Original Message -----
From: <donovanf@starpower.net>
To: <topband@contesting.com>
Sent: Wednesday, August 01, 2012 12:53 PM
Subject: Re: Topband: FCP model
> 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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_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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