Hello- I've been off the reflector for a few years, and now I return with a
specific question and reports.
In 1999 I put up a Glen Martin M-1870A 70 ft tower package that came with
Kevlar guys. The tower is guyed at 35ft and at the very top of the tower at
70ft.
Mounted about 2.5 ft above the top of the tower, and thus about 2.5 ft above
the connection of the top guys, is a F12 C31XR.
Last winter, one of the top guys broke where ice accumulates at the bottom
where the guy loops back on itself. I plan to replace all guys. I notice
that Glen Martin is now supplying EHS with their tower packages instead of
Kevlar.
I would consider replacing with EHS instead of synthetic, but worry about
SWR and pattern changes. I don't want a combination solution with part
synthetic and part EHS.
I've googled and checked archives - Anyone have specific experience how
changing to EHS might affect SWR at this height and with this antenna?
Now my report - (A+) After 6 years, I have not had to lower the antenna even
once. Contrary to the ideas of some, I have NOT found any rivets or element
parts at the bottom of the tower. Also contrary to some [old] reports, my
SWR is less than 1.5:1 all across the band. Great SWR on the other bands
too.
We have nasty winters here and it gets pretty windy in the spring. I have
nothing but good to say about the tower and the C31XR! (The guy break could
probably have been avoided if I had treated the terminations differently! I
just used cable clamps and taped the folded-over end of the cable in
tapering fashion from above downwards.)
Thanks! - John, WA9ALS
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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