As W8JI pointed out, it is a matter of angle. At my antenna farm a few years
ago, I Built two "killer" beverages. Each was a pair of phased 1500 foot
beverages ... one set on Europe and one on Japan. They were useless compared to
the vertical array and other beverages 600 to 800 feet long. I took doen the
European pair but left the NW pair up for two seasons. A few times it worked
better on a couple UA0 signals. There are more times 160 is open to very high
angles than very low ones.
John
> Date: Sat, 28 Sep 2013 10:45:41 -0700
> From: ac6dd@yahoo.com
> To: topband@contesting.com
> Subject: Topband: 5/8 wavelength vertical is mo betta than shorter versions??
>
> 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
> _________________
> Topband Reflector
_________________
Topband Reflector
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