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[Towertalk] 4-square vs 40-2CD

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Subject: [Towertalk] 4-square vs 40-2CD
From: (Tom Rauch)
Date: Mon, 8 Jul 2002 21:04:16 -0400
> Remember that a 4 square is only a 2 el vertical array with the
> ability to put out a uni-directional pattern in different directions. 

A four square actually functions as a three-element in-line array, 
not as a two element array.

The "center" two elements fed in-phase act as one element, giving the 
proper 1:2:1 current distribution. The phase in traditional arrays is 
slightly in error, reducing gain and F/B at useful angles, but they 
still have around 5 dB gain over a single element.

If you tweak the phasing to the correct values, the gain is over 6dB. 

> I seem to remember that several have installed an improved system
> using K8UR style 1/2 wave  verticals in a 4 square arrangement.  Even
> there it has been found that a 2el short beam was better when placed
> at say 120 feet on 80.   The gang with beams on 40 and 80 do very well
> cpmpared to any vertical array until you get to phased bob tail
> arrays.

A properly installed 4-square is competitive with either phased 
Bobtails or k8UR arrays. They don't work as well on 40 as a good 
Yagi, but they certainly can be competitive on 80. verticals work 
better on 80 and 160 than most models seem to indicate.

For example, my 3/8th wl vertical ties or beats a dipole at 300 feet 
virtually 100% of the time, with the only exceptions occurring during 
geomagnetic storms or during strong sunrise peaks. My dipole at 300 
feet beats a dipole at 85 feet by about 10-15dB virtually all the 
time, even during peaks.

The low dipole is superior within 200 miles or so at night time, but 
the high dipole and vertical tie or beat it at distances more than 

I have recorded five instances in three years out of a few thousand 
tests, where the low dipole beat the vertical at long distances.

By the way, the high dipole is 15 or more dB down in two directions.

On 80 meters I have less test data, but a 35 foot hat loaded vertical 
almost always tied a dipole at 110 or 120 feet into Europe....night 
after night.

On 40 I'd use the high 2 el loaded yagi, but I would not sell a 4-
square short without trying one. Especially for receiving, where gain 
is secondary to directivity.

73, Tom W8JI 

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