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 ```Thanks. I don't know if I understand all of that But I will think about it. My plan is to use a tiltover 22 ft tower to support a 25.7 ft tall vertical. The tower is actually part of the entire vertical antenna. It will have a 60 meter trap at the 43 ft point and will also radiate on 3.650 MHZ. Along side the tower will be an aluminum tube with a 30 meter trap and a small stinger above it. This will give me 30/40/60/80 meters in one assembly. I have the traps already made. Soon I will pour concrete and get this guy up in the air. Depending on other things, I may put a switchable base loading coil in for 160 meters. My winds in SW FL rarely get above 50 mph gusts. then there is a dead band in speed until you get to hurricane force winds. So, I am also including a base mounted hinged gin pole to tilt it over in really bad weather. Dan Schaaf K3ZXL "In the Beginning there was Spark Gap" www.k3zxl.com ----- Original Message ----- From: "Gene Smar" To: "Tower and HF antenna construction topics." Sent: Thursday, February 18, 2010 3:47 PM Subject: Re: [TowerTalk] wind load > Dan: > > For a RIGID vertical element (such as an antenna mast or a heavy > vertical made of thick-walled or solid tube), the force (say, 12.54 psf) > would be applied midway up the element, or at 11 feet above the ground or > tower top. (You can find the calculus for this in most introductory > mechanics text books.) The area this force is applied over is the > effective > area of the mast or vertical antenna. So assuming an effective antenna > area > of 3.67 sqft (the actual shadow area of a 2 inch mast 22 feet long), the > total force applied would be 12.54 X 3.67 = 46 pounds. The force would be > handlied as a force at 11 feet AGL or above the tower top. We all must > take > this additional force and area of the mast into consideration when > calculating the total wind force applied to the tower system. > > As for a real-world vertical that flexes in the wind, this will shed > some of the wind loading leading to a reduction in total force applied to > the vertical antenna. The actual number depends on how far the antenna > bends in the wind. But by using the non-bending answer for a rigid tube > you > will be taking the conservative (safer) approach. > > > 73 de > Gene Smar AD3F > > > > ----- Original Message ----- > From: "Dan Schaaf" > To: "Tower and HF antenna construction topics." > Sent: Thursday, February 18, 2010 3:02 PM > Subject: Re: [TowerTalk] wind load > > >> How does this wind loading information apply to a bertical antenna which >> is >> rigidly mounted at the base and flexes in the wind? >> In addition, if the vertical antenna is mounted on top of a 22 ft tower, >> which is anchored in concrete, how does this info apply? >> 22 ft tower is short in comparison and maybe can be considered >> non-movable >> and then the vertical can be seen as the same as if it were mounted on >> the >> ground. >> >> Dan Schaaf >> K3ZXL >> "In the Beginning there was Spark Gap" >> www.k3zxl.com > /towertalk > > _______________________________________________ > > > > _______________________________________________ > TowerTalk mailing list > TowerTalk@contesting.com > http://lists.contesting.com/mailman/listinfo/towertalk _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```