Topband
[Top] [All Lists]

Re: Topband: Inv L Config

To: Jerry Keller <k3bz@verizon.net>
Subject: Re: Topband: Inv L Config
From: Guy Olinger K2AV <k2av.guy@gmail.com>
Date: Tue, 6 Dec 2016 00:05:37 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
The horizontal section also radiates, more or less than the vertical
depends on the specifics. Easy to see in a very simple NEC model. If you
are opposed to radiation from the horizontal on principle, then put up a T.
But the radiation from an L's horizontal fills in the doughnut hole in the
pattern, essentially getting the energy for that by taking it away from
ground losses. Assuming that on 160 one has RX antennas because TX antennas
are notoriously noisy, then you only care about what happens to TX. Filling
in the doughnut hole helps to minimize or eliminate skip zones, and help
keep a run frequency running low power.

The effect of a particular change to wires applies more to where the
current is more. Given that, doubling the vertical wire is what you do. But
I would model that and see what it buys you. Do the change both in free
space and over ugly dirt.

73, Guy K2AV

On Mon, Dec 5, 2016 at 11:37 PM, Jerry Keller <k3bz@verizon.net> wrote:

> Is it advantageous to make both the vertical and the horizontal sections
> "fat" (for improved bandwidth), or is it enough to "fatten" the vertical
> (radiating) section ?  How much BW will 3" diameter spacers give me?
>
> 73,  K3BZ
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
_________________
Topband Reflector Archives - http://www.contesting.com/_topband

<Prev in Thread] Current Thread [Next in Thread>