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On Fri, 24 Oct 2003 15:49:41 -0500, Neil Down
wrote: lancer wrote in : On Thu, 23 Oct 2003 17:23:26 -0500, Neil Down wrote: "(Scott Unit 69)" wrote in : I wish someone who knew what they were talking about would tell the truth about this antenna.There is enough BS on this group as it is without more myths being spread. The funniest part this antenna is made by workman it is junk, the coils are low Q. No way on gods green earth it beats a full 1/4 wave. No, the coils aren't low Q Yes they are compared to a high q coil. What do you consider high Q? Q (Quality factor) is equal to the inductive reactance/the resistance or loss Capacitive coupling between the turns is part of the loss. The coils for that antenna are large diameter tubing, less resistance. They are spaced from eath other by at least a diameter, less capacitive coupling. They are "air wound", less loss due to the coil form. The coils on that antenna have a Q of 100-300 In a typical tank circuit of a transmitter, smaller wire wound closer together on a ceramic form, a Q of 20 is considered very good. You make think that those coils look like they do for show, there is a proven reason why large diameter, large gauge material is used for the coils. And its not just for the power handling capability. |