"Dick Green". wrote:
>
> That was easy. Now, how can you broadband a low (say, 60 feet up) 80M dipole
> or vee enough to cover 3500-3900? Is the "coaxial resonator match" the only
> route?
>
> 73, Dick, WC1M
>
> -----Original Message-----
> From: L. B. Cebik . <cebik@utkux.utcc.utk.edu>
> To: Lee.Buller. <k0wa@southwind.net>
> Cc: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
> Date: Wednesday, December 10, 1997 9:01 PM
> Subject: Re: [TowerTalk] Simple Dipoles
>
> >Lee:
> >
> >Re: 40 meter dipoles 50' up
> >
> >Your problem is essentially the same one brought up recently by Dave
> >Leeson. The feedpoint impedance of a dipole for 40 meters at that height
> >is somewhere in the 70-90 ohm region at resonance. Hence, a narrow 2:1
> >SWR bandwidth.
> >
> >Solution #1: place a 1/4 wl section of 75-ohm cable from the antenna
> >feedpoint to the junction with the 50-ohm cable.
> >
> >Solution #2: if the bandwidth still does not cover 40 meters completely,
> >place a 1/2 wl length of 50-ohm cable from the antenna to a point in mid
> >air. Then add the 1.4 wl 75-ohm cable section. Then continue the 50-ohm
> >cable run to the shack. This second system broadens the operating
> >bandwidth even further.
> >
> >The latter system is Dave's idea based on ideas from Frank Witt and
> >others.
> >
> >Hope this is useful.
> >
> >-73-
> >
> >LB, W4RNL
> >
> >
> >
> >--
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>
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Robert C. Wilson, published an 2 page article in QST called the "Fat
Dipole". His design goal was less than 2:1 SWR from 3.5 to 4.0MHZ with a
nominal height of 30 Ft. I've tried his design and it works. Sorry but I
dont have the date of the issue with this article. Larry WB6VGI/KG4ML
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