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On 5 Apr 2007 10:05:43 -0700, "art" wrote:
On 26 Mar, 21:49, (Richard Harrison) wrote: Art wrote: "Any thoughts as to why it sgould be so and the scientific facts to support it?" We have plumb lines and bubble levels which allow easy determination of vertical and horizontal directions. We often inhabit a nearly horizontal plane If we are as likely as not to communicate with any particular direction, an omidirectional vertical antenna makes sense. An inclined wire would favor some direction to the detriment of another. Sure a slopimg wire works but doesn`t reach maximum height or length as effectively as a vertical or horizontal wire would. Why a straight dipole and not a V-shaped element? The V-shape corrupts the nulls at the ends of the straight wire. Vertical and horizontal antennas are not solely accidents of history. Best regards, Richard Harrison, KB5WZI Richard, It is well known that near maximum "overall" polarity gain can be obtained by placing a vertical at right angles with respect to earth. Now -a -days maximum gain is required of a certain polarity which requires a specific accuracy of less than 1 degree . So yes, in your working years straight up is good enough but these days of WiFi and all that concentration is applied for purity of polarity which requires a resonance at around 3 degrees to the vertical. This can be determined arithematically according to known laws. Ofcourse as one moves higher this offset angle changes. This same phenomina or tilt angle applies for all polarities where maximum gain is required for purity of polarization.The days have gone where just putting up a wire satisfies all. Regards Art Educate me, Art, what is 'polarity' gain? Walt |