I agree Carl, but you do need the horizontal room, which I often did not
have in many of my locations.
That's why I kept coming back to the vertical dipole.
In the meantime I have begin using something hybrid.
I purchased an antenna called an End-Fedz Dipole.
It's of course a misnomer. It is indeed end-fed and it is a half
wavelength, but it is no dipole.
However, like my vertical dipole, it is pretty ground independent.
The problem is, it's hard to go up 66'.
I don't.
I go up 40' and out about 30', which raises the base about 4' off of the
ground.
This has three advantages:
- the point of maximum current is in the air where it belongs
- still pretty ground independent (does not have to have radials)
- increased high angle of radiation (NVIS) due to the horizontal part,
while maintaining a healthy low angle radiation . from the vertical part.
Seems you can have your cake and eat it too!
In theory, I need a bit of a ground, as you pointed out earlier, but in
theory, a single quarterwave elevated counterpoise will suffice. Haven't
tried that yet. I will when I get settled in Germany. It actually works
pretty good as is, with no radial.
There is only one problem with this antenna: the feedpoint match. It is
only rated for 200w.
If it turns out that the antenna performs as I suspect it will, I will build
my own using larger components.
Of course this is a monoband antenna. It can't be used effectively on other
bands, but I mostly only work 40 anyway, so it's ok to have a dedicated
antenna for that band.
My goal is to have my NVIS antenna and my DX antenna combined into one
antenna.
The XYL loves it when I reduce the amount of antennas in the yard. (they
must all be related)
We'll see.
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of N4PY2
Sent: Thursday, January 06, 2011 11:20 AM
To: tentec
Subject: Re: [TenTec] New and Improved Terminology (NVIS origins)
That's true. But the best solution is to use raised radials a few feet
above the ground (I used 10 feet). Just 3 raised radials has been show to
make the antenna as efficient as 10 to 30 ground radials. And you don't
have all the work of burying the radials.
Carl Moreschi N4PY
121 Little Bell Drive
Hays, NC 28635
www.n4py.com
----- Original Message -----
From: "Rick - NJ0IP / DJ0IP" <Rick@DJ0IP.de>
To: "'N4PY2'" <n4py2@earthlink.net>; "'Discussion of Ten-Tec Equipment'"
<tentec@contesting.com>
Sent: Thursday, January 06, 2011 11:14 AM
Subject: RE: [TenTec] New and Improved Terminology (NVIS origins)
> Carl, although you statement is perfectly correct, it can mislead one to
> believe that the vertical dipole depends "as much" on the ground as the
> quarter wave vertical does, and that is way way wrong.
>
> The normal vertical MUST have a good ground in the form of radials and the
> vertical dipole must not.
> However, the earth below it affects both antennas.
>
> Lay down 100 radials for a normal vertical and you will see a radical
> improvement of performance.
> That same radial farm under your vertical dipole will help but the
> difference is nowhere near so great.
>
> 73
> Rick
>
>
> -----Original Message-----
> From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
> On Behalf Of N4PY2
> Sent: Thursday, January 06, 2011 8:17 AM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] New and Improved Terminology (NVIS origins)
>
> The vertical dipole was about 5 feet above the ground at the bottom. The
> vertical dipole was 66 feet long. All vertical antennas require some kind
> of ground plane to be efficient, even vertical dipoles.
>
>
> Carl Moreschi N4PY
> 121 Little Bell Drive
> Hays, NC 28635
> www.n4py.com
>
>
> ----- Original Message -----
> From: "Ken Brown" <ken.d.brown@hawaiiantel.net>
> To: "N4PY2" <n4py2@earthlink.net>; "Discussion of Ten-Tec Equipment"
> <tentec@contesting.com>
> Sent: Wednesday, January 05, 2011 11:14 PM
> Subject: Re: [TenTec] New and Improved Terminology (NVIS origins)
>
>
>>
>>> Years ago I had a vertical dipole for 40 meters and a raised vertical
>>> with 3
>>> radials 10 feet above the ground. The raised vertical was about 6 DB
>>> better
>>> than the vertical dipole for European stations. The raised vertical was
>>> 10
>>> feet off the ground at the bottom with 3 full size radials (33 feet
>>> long).
>>> I like raised verticals.
>>>
>>>
>> How high above ground was the dipole? How long was the dipole? A half
>> wavelength?
>>
>> DE N6KB
>> _______________________________________________
>> TenTec mailing list
>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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