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> on short hatted verticles and he seems to agree with the 6' height . . . . .. I haven't read Cebik's article, but the issue is not that 6' is the magic number, but the goal is to raise the feedpoint to 1/2 to 5/8 wavelength high. With the feedpoint at 1/2 wavelength, you compress the lobe and get a slight gain at the lower angles. This is of course at the expense of the higher angles. One of the real pluses by going no higher than 1/2 wavelength is that you keep one big fat lobe over all the useful takeoff angles. Once you start raising the feedpoint above 1/2 wavelength, your lobes start to split, leaving nulls in typical arrival angles. Not good! Just remember that feedpoint height is dependant on frequency. If you optimize for 20m, you will have a big null at useful takeoff angles on 10/12 etc. Kenny K2KW -------------------------------------------- Force12Talk mailing list provided as a service by Force 12 Antennas, Inc. Force12 Web Site: http://www.force12inc.com To Submit Message to the List: Force12Talk@qth.com To unsubscribe and view the Message Archive: see http://qth.com/force12/list For problems with the list: contact n4zr@qth.com |