Bill,
Take a look at this. I think there may have been a QST or NCJ article as
well.
Simple, easy, and effective. It's what I use.
http://www.k8ur.com/pdfs/array.pdf
73,
Larry K4AB
(Or as you say "Apples and Bananas"!)
On Tue, Mar 8, 2016 at 7:37 PM, Bill via TowerTalk <towertalk@contesting.com
> wrote:
>
> I've always had real high towers and no restrictions on the amount of
> towers I could have. Out in KH6 it is different....one 90 footer on one
> plot of land. Since that is a hard and fast rule, the quad loop systems
> for 80 meters I've had on the mainland won't be nearly as
> effective...according to HFTA. I really can't get enough height for them
> to be real barnburners.
>
> So....I've decided to try a four sqaure. Soil here is clay and stays wet
> most of the time, plus I have enough room to lay out a good radial system.
> The grouind undulates a bit and slopes about ten feet or so in the
> direction of the Pacific which is about one mile away. The antenna site
> sits at 1100 feet so the slope once it gets off the antenna site is
> great...about 1 foot drop for every 5 feet of horizontal.
>
> I've decided to go the Comtek route for the control.
>
> Several questions:
>
> First, any thoughts as how the terrain where the antennas are located will
> affect operation? Also, any thoughts on how the big slope from the antenna
> location to the ocean will affect the signal. On HFTA it is a big help on
> 80 with dipoles etc. but I'm not sure how it will affect a vertical system.
>
> Second, I have two ways to go on the construction of the verticals. I can
> fabricate aluminum full size quarter wave verticals which of course will
> provide decent bandwidth, not as good as four towers, but better than wire
> verticals. One problem is the location. The closest element would be
> about 30 feet away from the tower whcih has seven Yagis stacked on it. The
> other three verticals are about 70-90 feet away(all to one side of the
> tower). Guy wires are not the issue (Phillystran), but the tower is. I
> have no way to model this thing so it's pure guesswork how much the tower
> and other antennas (40-6 meters) will affect the signal.
>
> Last, I could run four ropes from the tower at 84 feet and make wire
> verticals in a four square pattern around the tower. To increase bandwidth
> I am planning on running the vertical wires in a "cage". from what I've
> read that is the way to increase bandwidth. The problem with this of
> course is the proximaty to the tower. All four wires would be within 33
> feet of the tower and the seven HF/VHF antennas. So, the vertical system
> would "see" the seven antennas and the 90 foot tower. Again it is guess
> work on my part as to what effect they would have on the four square. No
> guy wires to consider since I am using Philly. The other issue is I am
> afraid the 80 meter verticals would screw up 20 meters on my triband stack.
>
> My gut feeling is the aluminum 1/4 wave verticals located slightly away
> from the tower would be less affected by the tower/antnennas. However, for
> ease of construction I really would like to do the vertical wires around
> the tower.
>
> This is my first foray into four squares so I would really like some
> opinions from guys who have experience in these matters.
>
> Mahaho for the help!
>
> Bill K4XS/KH7XS
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