At 06:50 AM 3/13/01 -0500, RoadRunner wrote:
>Thanks to all who responded - the article is available still at
>
>http://yagistress.freeyellow.com
>
>...I highly recommend it. As for philly - I was going to use it before I
>read the article. I am planning on stacked tribanders and a 4 el 80 mtr wire
>array but it is pretty convincing. As for people using it and getting away
>with it... the same applies to overloading towers! I know what I am planning
>would be considered overloading by Rohn (but not but much) - others out
>there are severely overloading and GETTING AWAY WITH IT! so....where do you
>draw the "comfort" line?
Certainly Phillystran is more elastic than desirable, and far too
expensive, but I would stop short of discarding the idea outright. The
modeling I have done suggests that it is very hard to get a decent pattern
out of stacked tribanders where the lower antenna is inside a conductive
guy set.
In my case, I was able to find a set of made-up (previously-owned) 6700-lb
Phillystran guys to use instead of the 4000-lb EHS in the top guy set of my
100' Rohn 25 tower. Because it is designed for a higher load limit, I
concluded that it would elongate less than the 4000-lb Philly under the
same load. And of course, my tower is not overloaded yet -- stacked C-3E
tribanders and a 2-el 40, plus a 4-el 80m wire array, is within the limits
of 100' of 25G.
BTW, the stack works great, and the performance of the 40m yagi on top also
improved considerably with the substitution of the Phillystran top guys.
73, Pete N4ZR
Contesting is!
The World Contest Station Database
is waiting for your input at
http://www.qsl.net/n4zr
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