Think of a dipole close to the ground, it will not be efficient with all
that coupling to earth and resulting losses.
73
Peter
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of David
Cutter
Sent: Mittwoch, 9. November 2016 17:37
To: Mike Waters; Rob Atkinson; topband
Subject: Re: Topband: 160 m inverted L
I recall reading from Ralph Holland that 0.015 wavelength was a good height.
David
G3UNA
----- Original Message -----
From: "Mike Waters" <mikewate@gmail.com>
To: "Rob Atkinson" <ranchorobbo@gmail.com>; "topband"
<topband@contesting.com>
Sent: Wednesday, November 09, 2016 4:11 PM
Subject: Re: Topband: 160 m inverted L
> Fifty feet?! That means the feedpoint --the bottom of the antenna-- would
> be 50 feet up! Do you know how high the top would have to be? I don't
> agree
> with that at all. And I've never heard of anyone who ever did that.
>
> The four elevated radials in these tests were just 16 feet high! And what
> is more, the frequencies were 1490, 1450, 1240, and (maybe) 625 KHz.
> Almost
> as effective as 120 buried radials.
> lists.contesting.com/_topband/2007-11/msg00248.html
>
> I forget the radial height in Rudy Severns' (N6LF) tests, but IIRC they
> weren't anywhere near 50' high.
>
> My two elevated radials were 10' high. I know that a little higher (and a
> few more of them) would have been better, but I can tell you that that
> 160m
> inverted-L WORKED! And I'm by no means the only one. :-)
>
> 73, Mike
> www.w0btu.com
>
> On Wed, Nov 9, 2016 at 6:10 AM, Rob Atkinson <ranchorobbo@gmail.com>
> wrote:
>
>> The rule of thumb for effective elevated radial height is 1/10
>> wavelength,
>> so on 160, around 50 feet up.
>>
>> 73
>>
>> Rob
>> K5UJ
>>
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