Hi John,
I'm curious, how low was the dipole, and what was the extent of the
radial system for the vert?
Also, how close to the water were they?
Thanks!
N1BBR :-]
>
> I just returned yesterday from the Virgin Islands. The station was about
> 300 feet high with a sloping terrain to the sea. On 40m a low dipole
> seemed noticeably better than a vertical with a poor radial system. I am
> unaware of any software that can model a vertical on a sloping terrain.
>
> John KK9A - WP2AA
>
>
> To: TOWERTALK@contesting.com
> Subject: [TowerTalk] 4 square for 80
> From: Bill via TowerTalk <towertalk@contesting.com>
> Reply-to: cqtestk4xs@aol.com
> Date: Tue, 8 Mar 2016 20:37:58 -0500
>
> 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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