Ch22 11-Element Folded Dipole Yagi (518-524 MHz) analyzed using 4nec2 [see *.nec.doc file below]. Design Dimensions for 11-El Yagi from rabbit73 post, calculated using fol. K7MEM Website: http://www.k7mem.com/Electronic_Notebook/antennas/yagi_vhf.html
Note that K7MEM Dimensions [for Cutting Elements] must be SHORTENED by the "Boom Correction" = BC * Element Diameter, when 4nec2 Model is constructed WITHOUT the METAL Boom, where BC=0.666. Boom Correction for ACTIVE Element is derated by 50% due to being mounted ABOVE the Boom.
Ch22 11-El FD-Yagi - 300-ohm K7MEM: Ch22 Raw Gain = 14.3 to 14.5 dBi, F/B & F/R Ratio Min. = 16.7 dB and SWR (300-ohms) = Under 1.8. BOOM LENGTH = 1433-mm (56-13/32 inches).
Unfortunately, K7MEM (like other "Formula Driven" Designs), are NOT OPTIMIZED [poor F/B & F/R Ratios]. Gain, F/B & F/R Ratios were Best on 529 MHz, vice desired 518-524 MHz and SWR Curve for 200-ohms is better than 300-ohms, although Both are "Acceptable" [not always true].
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