That’s what I got a double extended 80 zepp 166ft each side of center up
70ft. works great.
-----Original Message-----
From: John F.
Sent: Tuesday, September 16, 2014 9:40 PM
To: tentec@contesting.com
Subject: [TenTec] Zepp, zepp, zepp!
Here you go.....
Didn't know I'd start such a discussion. Bob has
what I understand and have understood through
the years...
John, K4AVX
Message: 2
Date: Mon, 15 Sep 2014 14:04:14 -0500
From: "Bob McGraw - K4TAX"<RMcGraw@Blomand.net>
To: "Discussion of Ten-Tec Equipment"<tentec@contesting.com>
Subject: Re: [TenTec] Zepp
Message-ID: <600883B68861416DBF706D8632892FC2@FAMILY>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=response
In review of the ARRL Handbook, Ed. 2014, Chapter 21.7, there are clearly
two distinct examples of Zepp antennas. One being 1/2 wavelength and end
fed with open wire line and the 2nd being a center fed 1/2 wavelength wire
fed with open wire line.
On page 21.7 we find: "Another variation, shown in Fig 21.12B, is the end
fed Zepp, named for it original application as an antenna deployed from
Zeppelin airships. The feed point impedance of a Zepp is quite high,
requiring open wire feedline and impedance matching techniques to deliver
power effectively."
The Extended Double Zepp is described as having an overall length of 1.28
wavelengths which equates to 0.64 wavelength on each side of the center
insulator and feedpoint. This antenna is reported to have ~3 dB of gain
to
its broadside. The length of the wire antenna is calculated as:
984/f(MHz)
x 1.28 = length in feet. The feed point impedance is ~140 ohms using wire
elements.
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