> My test was with the capacitive hat (the short radial rods)
> at the lower end of the antenna about 12" off ground.
That's a rather rough test for the R7000 or any "no radial
vertical." The radials are "hot" and couple rather heavily
to the soil. Performance should improve significantly by
moving the base up to 15 feet or so (1/8 wave at the lowest
operating frequency).
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Rudy Severns
> Sent: Monday, September 15, 2008 10:53 PM
> To: towertalk
> Subject: Re: [TowerTalk] R7000
>
>
> N2EA has it right!
>
> After I ran the test on the R7000 I had an exchange of notes
> with W1JR who
> was the original designer. He pointed out that there is no
> "other half of
> the dipole". It is loaded in such a way as to be complete.
>
> My test was with the capacitive hat (the short radial rods)
> at the lower end
> of the antenna about 12" off ground.
>
> While I didn't check it out on all the higher bands, it
> appears to me that
> it's a pretty good antenna for those with space limitations.
>
> The point of my initial comment was that, with careful design, it is
> possible to get reasonable performance from a vertical which
> doesn't have a
> large radial system either on the ground or up in the air.
> The most extreme
> example would be a simple full size vertical dipole. As you
> shorten down
> from the full 1/2-wave dipole there are reasonably efficient
> loading schemes
> which can be used to approximate the dipole.
>
> 73, Rudy N6LF
>
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>
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