Finally - I have a vertical in the air. With my available space and skyhooks,
I ended up with a 70-foot vertical section with a 70 foot flat-top topwire. I
decided on elevated radials since my ground is rocky, rootbound, and covered
with heavy brush. My feedpoint is 2 feet above ground which consists of a
6"x6" aluminum plate nailed to the top of a post and has an SO-239 panel
connector and numerous holes around the margin for attaching radials. My
radials slope up away from the feedpoint to 8 to 10 feet above ground for their
full run. 6 of my radials are about 1/4 wave and 2 are about 1/8 wave.
I measured feedpoint Z with a MFJ259B directly at the feedpoint after adding
one radial at a time. Here is what I got at f = 1.825 MHz.
1 radial: 60 + j60
2 radials: 176 + j0
3 radials: 41 - j12
4 radials: 46 - j13 (50 + j0 @ 1.840 MHz, and a 2:1 SWR of 1.800 to 1.890)
5 radials: 63 - j22
6 radials: 35 - j37
7 radials: 36 - j38
8 radials: 38 - j42
My feedpoint Z did not seem to follow any kind of orderly trend as I added
radials, and seems to have "leveled off" with 6 to 8 radials. Should I keep
adding radials? I am still way off the 16 - j75 that EZNEC predicts.
Steve KK7UV
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