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[TowerTalk] Requested additional info on 4 SQR from N0AH

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Subject: [TowerTalk] Requested additional info on 4 SQR from N0AH
From: (
Date: Tue, 31 Aug 1999 02:36:56 EDT

Got a lot of feedback with some questions that I can answer to fill in a few 
gaps of my earlier posting-  seems like I left a lot of details out- 

First, the top hat wires are at a 45 degree angle downward-  they are at 
about the same angle as the guy ropes-

As for raised radials- ON4UN really goes into detail on his single rasied 
radial system per vertical on his 80 meter four square-  I researched this a 
lot and found a variety of opinions on how effective they are or may not be 
compared to ground radials- ..... the findings seemed to indicate that the 
higher the raisied radials, the better.  But that is another topic for 
someone other than me - I feel like those three monkeys talking about the 
subject-  I see no, hear no, speak no on raised radials- hihi

But before building the array,  I emailed every one of the four square owners 
listed in ON4UN 3rd edition of world renowned DX'ers what kind of radial 
system they used...the vast majority used ground radials- some tried using a 
single raised radial over a good ground screen with decent results-  But 
after all my time investigating things, I just wanted to keep it simple and 
not screw around with the potential for interaction between the rasied 
radials that parallelled one another etc.....   -

Why 60 radials??? well, 30 radials are nice, but if your going to do it, 60 
really improves things while going from 60 to 120, per other's research,  is 
not as significant- so 60 seemed like a good number to settle on and is what 
Com Tek suggested-  many 4 sqr owners agreed that 60 seemed to be the magic 
number-   I cut them at 1/4 wave lengths to keep them uniformed from antenna 
to antenna-  

The distance of one wave length to buffer the antenna radial tips from other 
potential effects is my own paranoia- but it sounds good and makes me feel 
intelligent- although the dictionary states that is a sign of 

Actually, I do have a beverage running near by the tips of some of the 
raidals- and a few of the radials tips of my 160 Inv L actually come into the 
radial field by a few feet- but none criss cross the 80 meter radials- and no 
ill effects have been noticed- yet.......

Mutual coupling has been a big subject-  Like a few of you responding,  I too 
thought that the jump in resonance was a result of the 4 verticals being 
coupled through the hybred coupler-  but not true--  Charlie, W0YG,  
straightened me out on this-

He explained that the resonant point jump from where I first tuned the 
original vertical, standing alone, with no other verticals in the field, 
because of the mutual effect of the four vertical's proximity standing near 
one another. 

 To prove this, he had me disconnect all the feedlines from the hybred 
coupler to the verticals and test out each vertical by itself-  and you know 
what, the results were the same resonant point for each vertical as it was 
for the array- Each vertical showed a resonant point near 3.900MHz......the 
same frequency that showed the minimal power dumped into the dummy load with 
the array hooked up- thus, the most resonant point of the array agreed with 
what seemed to be the resonant point of each individual antenna- -

I'm sure the hybred coupler has some minimal effect, but the main factor 
influencing the "jump" is due to mutual coupling of the is a 
neat effect and one you may never see until you start working with 

And as for the "cheap feedline" I use to run back from the power dump port to 
the dummy load.......the coax run is around 400 feet-  the coax runs from the 
array back into my  shack where it is hooked up to the watt meter and then 
the dummy load-  it is all RG8 and/or 9913-  it is not RG59....I guess 
referred to by many as the cheap stuff-

The verticals are ground mounted.  They sit on 2 1/2 inch PVC, the gray type 
(the white stuff is too light) The PVC is 3 feet long with about 2 feet 3 
inches of it sitting in  concrete.  I roatated the PVC during curing and it 
allows me to pull it out of the concrete if I need to-  More importantly, it 
allows me to slighttly rotate the antenna to match it up with concrete 
guyline supports about 45 feet from the base of the antenna-  

The base of each vertical is about 8 inches off the ground-  I have the 
ground braid attached to the radials via a ground bus and the center 
conductor is attached about 1 inch from the base of the aluminum-  I'm 
planning to use hay bails and plastic bucket to shield the feedpoints from 
snow drifts later this year- 

The coupler is mounted in the center of the square formed by the verticals- 
it is attached to a 6 inch diameter log post in 4 bags of concrete-  The 
center support was important as I use it for atttaching guy ropes to- 
overkill???  maybe-  but we get steady winds here in SE Wyoming-   and the 
winter winds are really a pain-

I used conductive grease to insure good contacts between to aluminum sections 
and put in two screws to hold them in place and a metal O ring to squeeze 
them together-

I used the 0 ring connectors to attach the guy wires and top hats too- Care 
was given so as not to cut into the wire or guy ropes-  with minimal loading 
in the wind,  I dont foresee a problem- (famous last words.......)

I did seal the tips of the verticals using electrical tape and silicon-

Have I nicked named it yet??? Yes, my XYL calls it the Big-A-Lou because of 
all the aluminum we put into it- the Big A Lou 4 square by N0AH......has a 
ring to it- but after spending a month building it-  I don't see a product 
line anytime soon- hihi 

And my favorite question was more of a comment on forgeting to add to the 
cost of the antenna the $$$ for the two acres it takes up-  $800 bucks- 
really!  But thats SE Wyoming for you- I guess folks in San Fransisco or 
downtown NYC might consider other options to use 2 acres of land for but I 
can't think of anything better- (-:

phew- thats it for the first night of questions/comments-  I was amazed by 
the number of e-mails I got- I guess I forgot a few things- really nice to 
get the feedback- -   

73  Paul   N0AH   


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