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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