In a message dated 97-03-29 01:03:17 EST, stunroe@orion.branch-co.lib.mi.us
(stu) writes:
> Does anyone have experience with phillistran guys; strength, uv
> resistance, longevity, how they stand up to the elements compared to
> steel guys with insulators. If anyone has used both have you noticed any
> difference in your swr/radiation pattern between the two? They seem like
> the ideal solution for shunt fed towers for the low bands. What did you
> like/dislike about them?
Ah, yes - Phillystran. As non-conducting guy wire material, they do a
really good job when you want to minimize guy wire interaction when you're
loading a tower or want to have a populated tower with lots of antennas on it
(stacks, wire antennas, etc.).
The PVC jacket is primarily for UV protection but also keeps out
contaminants. The Phillystran should be terminated to the guy anchor with
EHS to keep it out of harm's way.
I use it at my station and feel that it has made a positive
contribution.
The one thing you didn't ask about is cost. What kind of ham ARE you?
Anyway, let's assume a 3/16 inch guy wire 100 feet long. An EHS
configuration would have 26 foot segments consisting of 10 Preforms, 4
insulators, 2 thimbles and 100 feet of EHS. The total cost of parts is
$74.50. The same 100 foot segment of Phillystran consists of 100 feet of
Phillystran, 2 Preforms and 2 thimbles. Its cost is $91.40 - an additional
cost of 23% over EHS.
Running the same excercise for 1/4 inch, the difference is an additional
30% for Phillystran.
Is it worth it? It is if you want the non-conducting benefits of
Phillystran. For towers that just have antennas above the top set of guys,
the benefits are less obvious.
73, Steve K7LXC
TOWER TECH -- home of the Mast, Antenna and Rotator Calculator program
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