On Fri, 14 Jul 2006 12:23:25 -0400, Thomas Giella KN4LF wrote:
>BTW I have a website on the inverted L at
>http://www.kn4lf.com/kn4lf52.htm but it's a 7/16 w/l linear
>loaded inverted L.
Your method is certainly one way to do it, but there are far
simpler ways. The link below describes the one I think when you
say "inverted L." His discussion is quite solid from an
engineering point of view.
I agree with all of his comments re: ground system and maximizing
the vertical portion. His selection of overall length to make it
load well on several bands is also intersting.
In essence, the overall length makes the antenna easier or more
difficult to load, and the vertical section produces the most
useful radiation. Also, the distribution of current on the
vertical section, as well as the interaction of the vertical
section with the earth around your station, are mostly what
establishes the vertical pattern (that is, high/low angle). What I
think you are doing by varying the length of those horizontal
sections near the ground is putting the current maximum on the
vertical section so that it produces the nicest low angle pattern.
Jim Brown K9YC
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