Wellllll......there are several things to consider.
First of all, there are alternatives to Phyllistran other than steel with
insulators. Polygon makes a fiberglass guy rod which I and others use for the
guy wires on our large towers. I use 3/8 inch O.D. fiberglass guy rod. You
can see closeups on my home page: http://www.erols.com/n3rr Fiberglass guy rod
with GlassGrips from P.L.P. (Preformed Line Products) will cost you less than
Phyllistran or steel/insulators if you can buy at least 1500 feet of fiberglass
guy rod. There are special handling considerations which are too lengthy for
posting here at 1:00 am EDT.
For me, I wanted the minimum degredation due to guywire resonance affecting my
antennas. I also intended to (and did) have wire antennas coming off the
tower. So, I decided on Polygon fiberglass guy rod from the tower guy point to
a point 20 feet above the ground where it transitions to 5/16 inch steel. (See
a previous post by Fred, K1VR). BTW, the 3/8 inch fiberglass guyrod has a
breaking strength approximately the same as 5/16 inch steel (approx 13,000# for
each). I do not have to wonder if the guy wires affect the antenna patterns.
Equilzation plates ensure that there is only one resultant force on the guy
anchor. Without the equilization plate, the guy anchor has multiple (three in
the posted example) forces on it and must resolve those forces within the guy
anchor rod rather than having only one force on it. The equilization plate is
designed to resolve those forces over the size of the plate. The guy anchor is
smaller and designed to accept the single force in a longitudinal direction.
(All assuming a single rod-type guy anchor). Will a guy system work without
equilization plates? As K7LXC would say: "When in doubt, do what the
manufacturer says." BTW, I use equilizer plates on all of my guy anchors
(which are 10 ft 8 inch, 8 inch-face I beams (8I23), elevated 6 feet out of the
ground). The design of these I-beam guy anchors is more complicated than I
just mentioned, so don't just copy what I wrote here. I will expand on this on
my website soon.
I like to be able to sleep at night knowing I've designed and implemented a
SAFE tower/antenna system, used commercially accepted safety margins and
installed the system in a professional manner. Do I do this with all of my
amateur systems, no, I cut corners in the design of my keyboard drawers for my
PCs, in the shelf I fabricated in my shack to hold my rotor controllers, in the
trash can I use in my hamshack...in other words in the meaningless things. In
the very important structural issues that, if they fail, would cause personnel
and/or property damage I CUT NO CORNERS. Think about it. Visit my website.
henry gillow-wiles wrote:
> 2 questions
> 1) Can I get good results with Phyllistran on the top guy only, or do I
> need to have the stuff on the next guy down? 90 ft of 45g and guys at 30,
> 60, and 90 ft. Antennas at the top only.
> 2) What do equalization plates do and do I REALLY need them?
> Thanks a bunch.............
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