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## Re: [TowerTalk] Horizontal tower movement at the top

 To: "Gerald Boutin" , Re: [TowerTalk] Horizontal tower movement at the top "W7CE" Tue, 8 May 2007 07:37:00 -0700
 ```Gerald, Thanks for the pointers to the engineering data. That gives me exactly what I need. It also reminded me of an analysis that K7NV has on his website at: http://k7nv.com/notebook/towerstudy/towerstudy1.html I need to read it again in detail, but the baseline model in the study is very close to my situation. A quick glance indicats that movement of 6" or so in a 90MPH wind might not be all that unusual. It also reminded me that putting the tower on a pier pin will reduce the stress on the base. I'll read the study more carefully and also do the calculations based on EHS stretch. I originally planned to use the 25G only as a ladder, but if I can also mount the antenna to it, it will simplify the antenna installation. I don't think it should make much difference structurally since the tree and the tower will move together. Thanks again. 73, Clay W7CE > If you stick a 25G on a pier pin, you can pretty much ignore what typical > tower movement might be. The tree is going to be holding up the tower. > > I sort of liked the suggestion to put up a ladder instead. So, what would > be > a good ladder? How about 100 feet of 25G? > > If you still want an answer to your initial question, it is relatively > easy > to approximate when you know how much guy wire stretches and use the data > from the Rohn catalog and the law of cosines equation. > > Law of Cosines Equation > (http://www.ajdesigner.com/phptriangle/law_of_cosines_equation_angle_a.php) > > Guy Wire Stretch > 6.77 inches of stretch per 100 feet of 3/16" EHS when under a 3000 pound > load > http://k7nv.com/notebook/topics/guycable.html) > > -- > Gerald Boutin, VE1DT _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread Re: [TowerTalk] Horizontal tower movement at the top, Pat Barthelow Re: [TowerTalk] Horizontal tower movement at the top, SavageBR Re: [TowerTalk] Horizontal tower movement at the top, Gerald Boutin Re: [TowerTalk] Horizontal tower movement at the top, W7CE <= Re: [TowerTalk] Horizontal tower movement at the top, Roger (K8RI) Re: [TowerTalk] Horizontal tower movement at the top, Robert Chudek - K0RC