Ulli
I think the top hat should be as large as possible, however if it is not
possible to top load to nearly resonance ,you do what you can. As example on
a 30ft ant, a hat with 4 108" ss whips in a horiz X config will allow you to
drop the L needed from 69uh to 36uh .This gets you 3.3 db.Connect the ends
of the whips together with some #16 wire and the L drops to 28uh and another
1 db.The angle of max rad is still 25Deg in all the examples.Thats only
about 6 db (one S unit?),and 2DEG down from a full size 1/4 wave. I hope I'm
close to being correct, cause that is what I'm probably going to put up. The
whips eliminate the need to have wires guyed off all over the place, and to
upset the war department.The ground system in the yard is hard enough!
(You married guys know what I mean)
Bud W0HG
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