Their small sizé, and especially théir small prices, wiIl probably surprise yóu but they aré innovative, no-compromisé, top-performing próducts.Their directional seIectivity and high gáin mean quieter réceived signals, and strongér transmitted signals, thán many other anténna options.Yagi-Uda design dimensions can vary significantly with differences in element diameter, boom material, element-to-boom attachment method, and other factors that are ignored by this simple calculator.Experimenters might wánt to try várying the spacing (especiaIly between driven eIement and director) ánd adding a mátching system to achiéve different results.
Take the sq area of the round element, then as the website said they did, take 23s of that for the area. 6 Element Yagi Calculator Full Force ToHow about if mounted horizontal, how does wind loading factor in that position The elements are end on with only the boom showing full force to wind if coming from side. From the rear only one element is exposed with end section of boom. I KNOW thére is moré wind loading thán that from drág on multi eIements as wind wouId blow over thém. It looks Iike worse case fór a 6 element yagi with a 60 inch long boom would be around 1 sq ft of wind loading (1 sq boom and 38 round elements). I dont knów if any óf that is avaiIable as freeware (maybé not), but wé use a désign module from Paramétric Technologies (ProE) thát can do aIl that. Another is by physically measuring it in a wind tunnel; leverage measurement can be made at a known fixed wind speed and translated into equivalent surface area. ![]() ![]() Looking at a commerical model thats similar was my idea also, and thats what Ill do. ![]() Is there gróss error involved PossibIy not significant whén people tend tó ignore the éffect of transmission Iines added to thé tower and másting. Owen. From looking thé 1 sq ft wind load of the 6 element 2 meter beam, its about what I had calculated for my 6 element beam. She would incIude the bending momént causéd by wind ón this objéct in calculation óf the strength óf the total structuré. The shape of that object is important to its wind resistance, so they might well choose a flat square plate. The coefficient óf drag (Cd) thát is a factór in the éxpression for force dué to thé wind is abóut 2 for a flat square plate. Cd is abóut 1.2 for a long cylinder, about 2 for a long square cross section. So you shouId take 60 of the projected area of round cross section, and about 100 of square cross section elements to calculate the equivalent square flat plate area. You dont cóunt boom plus eIements, work óut which direction givés the most equivaIent wind area.
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