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[TowerTalk] Re: 4-Square elevated radials

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Subject: [TowerTalk] Re: 4-Square elevated radials
From: JEH@on.mobile.telia.se (Jan-Erik Holm)
Date: Wed, 23 Apr 1997 10:09:31 GMT+1
> This years antenna project is an 80M 4-square.   My question is about the 
> elevated radials.  I have asked three individuals how their radials are layed

> out and I received three answers.
>
> 1.  Only two radials, each bisecting the square and extending a quarter wave 
> past each vertical.  Opposite verticals in the square are connected by the 
> radials.
>
> 2.  Four radials for each vertical, laid out to look like a pound sign  #  
> from the above.  In this layout, adjacent verticals are connected by the 
> radials.
>
> 3.  Four radials for each vertical, laid out randomly, with NO connection 
> to radials of another vertical.
>
> Three rather different approaches.  I solicit your thoughts.
>
>     tnx/73    Tom   WB8ZRL

Too few radials to get good efficiency, I think at least around 50 on each
antenna would be needed.
I used 100 radials on each antenna elevated 20 feet on a 80 mtr 4 SQ and
the antenna was a pure killer. That antenna did crach and after rebuild it
became 40 radials per ant elevated 10 feet, I will increase number of radials
this summer. This second version seems very close in performance but I think
it is a wee bit down in killer strenght compared to the first one.
Also I have a 4 SQ on 40 mtr with only 16 radials per antenna and it seems
to have descent performance but I dont think it is up to killer performance,
at times I´ve been able to beat 3 el Yagis at 120 feet but generaly that isn´t
the case.
I have never confirmed anything with measurments but a lot of people claims
that at least 60 radials is needed for good performance and it seems to me 
that that is perfectly true.
My 4 el 40 mtr Yagi is on the ground waiting for a new tower so when I get
that on up I will have some kind of  some kind of referens antennna, 4 SQ still
will
be a good idea since it is possible to change beam direction within 1 second,
also on my 40 mtr 4 SQ I run  8 directions instead of the usual 4 and it sure
pays
off, took a bit of doing to get all phaseings and impedances right but after
it´s
set up and adjusted it works great.

73 de Jim SM2EKM     jeh@on.mobile.telia.se


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