Particularly for the very minimal radial systems some are forced to live
with, not having high angle radiation may actually be a considerable
advantage.
If one does not have "dense" and uniform radials the ground field
cancellation advantage of radials is lost, and having a low current center
on the vertical section now is a lossy issue. The max would be right at the
grass or at the base of elevated radials, basically as low as you can get.
Since for many this ground cancellation advantage cannot be had on their
property, the next best thing is to get as much current center as far UP on
the vertical wire as is possible. My current center is between 70 and 90
feet up on the wire and the horizontal is 105 feet.
My driveway bisecting the area under the only plausible wire location would
not have allowed a "T," but reflection on the issues says I'm better off
with the L.
Given how lossy some grounds can be, and with less than dense and uniform
radials, for a given installation a "short" T may simply be *throwing away*
the energy not radiated at horizontal angles. Remember that the
horizontally polarized radiation is not subject to the horrendous ground
losses of vertical polarization.
With vertical antennas on 160, the five ton elephant in the room is what one
is doing about ground losses. Everything else is yippy puppies. Unless one
has an excellent radial system, reducing ground losses is about the only
significant question.
73, Guy.
On Fri, Oct 14, 2011 at 8:55 PM, ZR <zr@jeremy.mv.com> wrote:
>
> ----- Original Message -----
> From: "ZR" <zr@jeremy.mv.com>
> To: "Jim Bennett" <w6jhb@mac.com>; <topband@contesting.com>
> Sent: Friday, October 14, 2011 8:49 AM
> Subject: Re: Topband: Fwd: Capacitor for Inverted L
>
>
> I dont understand the sudden urge or desire of some to suppress all high
> angle radiation
> from an inverted L. It is well established that even a low horizontal
> dipole
> can work amazing amounts of DX on 160 when conditions allow and having both
> possibilities present in the L is a benefit.
>
> Carl
> KM1H
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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