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Topband: 5/8 wavelength vertical is mo betta than shorter versions??

To: "topband@contesting.com" <topband@contesting.com>
Subject: Topband: 5/8 wavelength vertical is mo betta than shorter versions??
From: Niko Cimbur <ac6dd@yahoo.com>
Reply-to: Niko Cimbur <ac6dd@yahoo.com>
Date: Sat, 28 Sep 2013 10:45:41 -0700 (PDT)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
>>??? ______________ >Note that for 1 kW of applied power, the maximum inverse 
>>distance field 1 
>mile from a 5/8-wave vertical is 275 mV/m compared to 195 mV/m from a 
>1/4-wave vertical. >The difference is 20log(275/195) = 2.99 dB, which supports 
>the point of my 
>post.
Sure, over perfect ground the 5/8 wl has 3db more gain at 0 degrees elevation.. 

You are talking about theoretical gain.  I am talking about real world 
experience.

Even if you have access to a location surrounded by Saltwater (like me) the max 
gain of a real 5/8 wl vertical over 1/4 wl is going to be about 2.2 dB,and the 
elevation angle 5 degrees, the vertical beamwidth 17 degrees.
Over Average ground - which was where we set up the two verticals in the first 
place,
the gain of a 5/8 wl is some 2dB less than the 1/4 wl vertical, the main lobe 
at 15 deg, and the BW 23 deg.
The 1/4 wl main lobe is at 26 deg with BW 42 deg!
After having said that if I only could put up one antenna I would choose an 
Inverted L over salt water (again).
Niko AC6DD 
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