R65 is VERY heavy duty stuff ... coupled with 11200# philly I’d suspect that it
would indeed feel very strong! My point was only IF K7NV’s analysis is correct
and I’m surely not in a position to dispute it – and IF one has their bottom
section in concrete (and important consideration for the analysis) .... then
the conclusion would be that EHS is stronger than the equivalent philly. As
simple as that. So if a tower has survived with the philly that would only
suggest that it would have had more margin if it had been EHS. The fact that a
tower has survived thus doesn’t prove that philly is as good – it only proves
that it is good enough for what THAT tower has seen since installation. Which
I’m sure is indeed ‘good enough’ .... but it doesn’t imply it is equivalent!
At least that is how I’d interpret his analysis.
as for life expectancy – if salt air is an issue I can see how this might
affect the decision – but for most it isn’t a concern. There are just as many
if not many more anecdotal stories of both ham and commercial towers with steel
that have been up for 40 or more years and still doing fine.
Gary
I have a 150' Rohn 65G tower guyed with 11,200 pound Phillystran and Ihave no
concerns about guy stretching. The tower feels solid and it has been up for
years at two different QTH's with no issues.I used Phillystran at my Aruba
station. Steel guy cables and grips neededreplacement every four years and the
Phillystran was still in excellentshape when I dismantled the station.
John KK9ATo: <towertalk@contesting.com>Subject: Re: [TowerTalk] Rotating tower
guying questionFrom: "StellarCAT" rxdesign@ssvecnet.com
Date: Mon, 4 May 2015 08:57:34 -0400Just as a reference:I had a 141? rotating
R45 tower in AZ ... the guys were attached at about120?(top) and out ~105?. I
used 1/4? throughout. I used insulators throughout aswell using the values
provided in the handbook.thoughts:-I stayed with EHS because of the article
written by K7NV regarding towersandguys and the fact that philly stretches so
much more than EHS. That concernedme greatly.-Although there is extra labor in
adding the insulators I?d say it mightbe, asit was for me at the time, a
non-issue as it is a one time adder and not THATtime consuming. Its not as if
you?re getting paid for the hour if youDIDN?T doit!-The values in the
handbook... the one thing they don?t seem to take intoaccount is the shortest
length going to the tower ? I believe mine waslike 6?or something similar ? but
it is that x2 (or x3 considering all three) ANDthewidth of the tower so for me
it seriously interacted with 10 meters, a bit
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|