Don't bother dreaming! :)
I was seriously considering using the WIDE SPACED layout for my 80m 4Square
with Comtek box as I had enough space and material. I abandoned the idea
after a lot of modelling and analysis.
GAIN:
3/8 spacing has up to 0.5 db more gain depending on soil but you have to use
3/4 wl long phasing lines instead of 1/4 wl and the main feedline will
likely also be longer - if you use RG213 for example the extra ATTENUATION
WILL EAT UP ALMOST ALL THE GAIN.
LOW ANGLE RADIATION: it's a myth. The front lobe does not change almost at
all. The main radiation angle will be the same.
F/B: It is probably the biggest adventage. The high angle (30-50 deg) F/B
improves considerably. But it is deceptive as it improves only opposite to
the front lobe - at 180 degrees azimuth. In the same time the F/B gets much
worse at about 30-45 degrees off the back - two large lobes emerge there. So
in total I would not be sure I would prefer the 3/8 pattern at all.
Thus, taking into account that the only questionable advantage is pattern,
but definite disadventages are space needed, radial wire needed, cable
needed...the decision was an easy one to be made.
I do get a lot better pattern (c.a. 10 db better F/B) compared to
conventional ground mounted 4Square by:
1. Elevating the verticals by 3 meters
2. Using 1 connected radial per each vertical diagonally out from the
center.
Ground losses are eliminated by extensive ground screen of 64 1/4 wl radials
per vertical on ground not connected to the antenna.
I do see a very good F/B on all signals including high angle ones.
73and happy new
tonno
es5tv
----- Original Message -----
From: "Richard M. Gillingham" <rmoodyg@bellsouth.net>
To: "W0YG Charlie Summers" <w0yg@plusten.net>
Cc: "TowerTalk" <towertalk@contesting.com>
Sent: Saturday, January 04, 2003 5:33 PM
Subject: Re: [Towertalk] Free Standing 80M four square for sale
> Ahhh..... But to have SPACE for such an array... One may dream..
>
> Gil, W1RG
>
> W0YG Charlie Summers wrote:
>
> >I have four free standing base loaded Force 12 80M verticals that I
> >currently use in a four square. I want to sell the antennas and the
phasing
> >box. I will sell the four antennas separate for 1000.00 or the four
> >antennas with the Comtek phasing network for 1250.00. I also have four
3/8
> >wave 50 ohm phasing lines that are essentially new with connectors each
end
> >for $275.00. I will split or combine in any way but not separate the
four
> >antennas. They are 39' 6" tall with a humongous base loading coil.
Buyer
> >to pay shipping. I think I have boxes.
> >
> >I mount the bottom of each vertical to a 4x4 post in concrete. I
currently
> >have the four square installed and operating. The antennas are
> >approximately 8 feet off the ground at the base. They are in good shape.
> >The phasing network and phasing lines are essentially new.
> >
> >The phasing lines are 3/4 wave length long so you can install the
verticals
> >with 3/8 wave spacing which Comtek calls their "Super" four square for
lower
> >angle hence better DX.
> >
> >73,
> >
> >Charlie, W0YG..>>
> >
> >
> >_______________________________________________
> >AN Wireless Self Supporting Towers at discounted prices,
> >See http://www.mscomputer.com
> >
> >Wireless Weather Stations now $349.95. Call Toll Free,
> >888-333-9041 for additional information.
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> >
> >
> >
>
> _______________________________________________
> AN Wireless Self Supporting Towers at discounted prices,
> See http://www.mscomputer.com
>
> Wireless Weather Stations now $349.95. Call Toll Free,
> 888-333-9041 for additional information.
> _______________________________________________
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