K1FO and computer optimized yagis tend to squeeze the first director close to the driven element. He emphasizes that wide first director spacing to get the feed impedance up. He bases director lengths on reactance change or phase angle. Director lengths taper smoothly from the first to the last director. 1 wavelength up to 0.4 wavelength then don't change any more. Director spacings taper smoothly from about. The first director isn't too close to the driven element. The characteristics of a DL6WU yagi include: The driven element Z is 50 ohms or 200 ohms with a folded dipole. The works published in UKW Bericht and VHF Communications by DL6WU in the 80s (as I recall) on optimal yagi design are the first to design a yagi that works well by theoretical means. What this shows is that there are several ways to accomplish the slow wave structure that cause the focusing and so the gain of the yagi. (copied for the CC 32 or whatever it was). There have been yagi designs with constant length and spacing directors without taper, and some (like the longer NBS) with tapers in both directions, often a longer director furthest out front. If you check the director spacings you will find eventually they reach a spacing of 0.4 wave and stay at that as you go forward.
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