Extended Double Zepp HF Antenna
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Horizontal Directivity Pattern for the Zepp Zepp consist of 0.64 wavelength elements

The calculator below will provide proper element and Ladder line length.

MHz

= ft. (or inches.)

The Zepp, short for Zeppelin is any resonant antenna end-fed by ladder line. A Double
Zepp means a center-fed antenna. This extended version provides 3 db gain over a
dipole. The double Zepp consists of two collinear 0.64 wave length elements fed in
phase. The diagram above shows current distribution in a double Zepp antenna.
The 1.1 balun is used to connect the 450 ohm ladder line to 50 ohm coaxial cable.

The only adjustment is in trimming the 450 ohm line matching section to best SWR.
Shorten about an inch at a time until best SWR is reached. The Double Zepp works
well on any of the amateur bands. The Zepp is a very good portable QRP antenna.
Build one for each band.

Martin, GD7JWR

 

 

© Copyright 2001 - gd7jwr, the only ham on the isle of man = All rights reserved

 

Text Box: UK Band PlanText Box: GD7JWR LinksText Box: Windom Antenna Text Box: GD7JWR Home.                                                                                  

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