If a quarter wave sloper is merely a method for feeding a tower.....
what happens if you have multiple 'slopers', like radials around the
tower?
K3ANS has an "inverted sloper system"....where the tower is fed
against an array of quarter waves symmetrically placed around the
stick. I think there are 8 of them. The tower is 120', with 3 el 40 on
top. Sloper height is 80' or so, although my recollection is hazy
at this point.... The center conductor of the coax connects to the tower,
and the shield to the slopers, or radials, or whatever they are. No effort
is
made to isolate the feedline, but it's well over 300' to the shack from the
feedpoint.
In short, the antenna is a killer. Operating in contests from Bill's, I've
heard
stuff in deep pacific that others with beverages couldn't, and worked stns
that others in the area couldn't.
I'm curious about how the lower portion of the tower factors into the
equation. Same for the earth connection. Tower is grounded.
With respect to having the high current portion of an antenna in the air...
Cebik says
it's important. The higher, the better. But we also have to realize that
50' is not high at 1.8MHz. Neither is 100'. 130' is quarter wave...and twice
that wouldn't be considered 'high', for a horizontal antenna....merely
acceptable.
Ground at 1.8MHz is not the same as what we see at 300 Terahertz.....so my
Carolina Windom 160, 140' up in Vermont pine trees, might well have been 300'
high .
My well had to go down 250 feet to get to an aquifer. So the effective first
reflection
'ground' might easily have been 100' or more below what my eyes perceived.
n2ea
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