I dare say that radials are useful under *any* kind of antenna.
Anything we can do to decrease ground losses is a Good Thing.
A vertical 1/2 wave antenna isn't fed "against" ground as is a 1/4
wave vertical. Ground currents are a minimum at the base of a 1/2
wave vertical, and the current loop is distributed much further out,
over more area, which means that the current density is reduced, So,
the magnitude of the current is less, which means that the ground
losses are proportionately reduced. though not eliminated. Current at
the base of a 1/4 wave vertical is a maximum, and ground losses are a
much more immediate concern.
Ideally, we'd place our antennas on an infinitely flat plane made of
copper, but the expense tends to be the zero-order limit on our
ability to do that.
Kim N5OP
At 11:01 AM 6/14/2008, you wrote:
>A 1/4 wave 80m vertical series fed on 40m is nothing else then a halve wave
>vertical on 40m which was questioned about.
>A vertical dipol can be fed at one end, center feed is no must.
>Radials are useful below ALL kinds of vertical antennas anyway.
>
>73
>Peter
>
>-----Original Message-----
>From: Richards [mailto:jruing@ameritech.net]
>Sent: Samstag, 14. Juni 2008 17:28
>To: Peter Voelpel
>Cc: towertalk@contesting.com
>Subject: Re: [TowerTalk] Vert. 1/2 wave dipole vs Hori. 1/2 wave dipole?
>
>Are you talking apples to apples?
>
>I thought the question was a vertical dipole vs a horizontal dipole of the
>same size.
>
>It sounds to me like you have a vertical with radials vs a horizontal dipole
>...
>
>/////////////// K8JHR ///////////////
>
>
>Peter Voelpel wrote:
>
> > I used a L-tuner with my 1/4 80m vertical above 3km of radials 20-30m
> > long and used an inverted-V dipol at 30m height, ends at 20m. Distance
> > between antennas 150m with negiable line losses.
>
>
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>
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