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[TowerTalk] Simple Dipoles

To: <>
Subject: [TowerTalk] Simple Dipoles
From: \"Dick Green\"."< ("Dick Green".)
Date: Wed, 10 Dec 1997 22:16:31 -0500
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

73, Dick, WC1M

-----Original Message-----
From: L. B. Cebik . <>
To: Lee.Buller. <>
Cc: <>
To: <>
Date: Wednesday, December 10, 1997 9:01 PM
Subject: Re: [TowerTalk] Simple Dipoles

>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
>Hope this is useful.
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