I've read that the minimum lengths for ground radials is no shorter than
the height of the antenna and that 50% of ground losses occur in the first
one-quarter wavelength distance from the antenna.
This tells me that "too long" radials have diminishing returns.
I've played the radials on ground game for years; I think this year I want
to try a pair of elevated radials as Mike W0BTU suggests.
73 Mark K3MSB
On Sun, Feb 18, 2018 at 6:56 PM, Charles Moizeau <w2sh@msn.com> wrote:
> Well it is understandable. The current maximum in the half-wave antenna
> is lifted well above ground level. Had there been a radial system it would
> have had to employ very long radials, for most of the vertical's radiation
> would have been hitting the ground at points far away from the base of the
> vertical. It is only at those distant points that very long radial wires
> would be able to gather the radiation from the ground's surface and feed it
> back to the feedpoint.
>
>
> Charles, W2SH
>
>
> ________________________________
> From: Topband <topband-bounces@contesting.com> on behalf of Mike Waters <
> mikewate@gmail.com>
> Sent: Sunday, February 18, 2018 6:31 PM
> To: Roger Kennedy
> Cc: topband@contesting.com
> Subject: Re: Topband: 1/2 wave inv L
>
> Yup! The lack of a radial system explains why the 1/2w vertical worked
> better. :-)
>
> 73, Mike
> https://nam03.safelinks.protection.outlook.com/?url=
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> On Feb 18, 2018 4:55 PM, "Roger Kennedy" <roger@wessexproductions.co.uk>
> wrote:
>
>
> Many years ago, a friend of mine used to operate on 160m with vertical
> antennas suspended on a big Weather Balloon filled with hydrogen . . .
>
> After using Quarter-wave verticals for a few months, he changed over to
> Half-wave verticals . . . he found they worked much better !
>
> He didn't have much of a radial system (due to lack of space), mainly just
> earth rods at the base . . . so I suspect that's one of the reasons why.
>
> Roger G3YRO
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