If you know your desired frequency, gain, length of boom etc, then you can determine other parameters from the supplied excel sheet. For example, the author has built a short 13 element Yagi using one meter long 15 x 15 mm square Aluminum boom, elements are 4 mm hard aluminum wire.
Cut elements according to the software results. Accuracy should be within 0.1 mm. Phase the edge at one side of the elements. Drill holes in the boom, first 3.8 mm then 4 mm. Hammer elements thru the boom, phased side ahead.
Elements must fit tight and must have and keep good electrical contact to the boom!
Reflector can be made from the same wire as the elements. To improve f/b I use perforated sheet (see picture below). The reflector is mounted to the boom using small brackets cut from 90° aluminum profile.
Radiator is made from 3 mm copper wire. Wire diameter is not critical, large diameter = more broadband, small diameter = easier to bend.
To match the 200 Ohm (symmetric) radiator to 50 Ohm (unsymmetric) coax a 4:1 Balun is required. It could be made from coax cable cut to one half wavelenght (l) and bent to a loop.
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