No idea. In his article, you can infer on fig 17 that 4' on a 40m
antenna is about 0.06 WL. And going from 0.5 to 4' was worth about 3/4+
of dB. Is there a reason to think that height above ground should
remain a on a flat trajectory? From fig 16, it looks like the curve is
bending and my guess is that a study would show an asymptotic point is
reached. My point is that "louder" would be relative - maybe going from
5' to 20' on 160m radials without moving the physical vertical does
provide an improvement but it's not going to be massive. From the graph
it would be sub 1dB.
I eventually got rid of the elevated radials here and put the 40m 4sq in
the ground. But it had nothing to do with signal - it had to do with
the maintenance needed to keep them up and I was tired of messing with
them.
A vertical offers no free lunch with elevated radials. Sure you have a
big spend and a hassle getting a ground mounted system put in, but then
you are relatively free of maintenance going forward. On the other
hand, hanging elevated radials is a lot easier, but the maintenance is
ongoing and if you have deer, ice and whatever, its bigger.
A guy was joking with me once when I told him that a deer would only hit
his beverage once and would learn the lesson. A beverage is not an
elevated radial but the maintenance is the same. He replied, that "up
here, the deer are called moose and the don't even register hitting and
breaking your beverage wire." Had to say, that was a new one one me.
No moose in KS!
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 1/21/22 4:58 PM, Jim Brown wrote:
On 1/21/2022 2:14 PM, Joe Subich, W4TV wrote:
I don't believe N6LF has done any work with elevated radials at 0.05
wavelength or greater above ground.
It's been a while since I studied Rudy's work, but I do remember that
when I interpolated his 40M work on elevated radials to 160, I needed
them much higher. And when I raised them to 20 ft, as N6BT advised me,
my signal got louder. But I've learned a LOT from Rudy's work, which I
value greatly.
73, Jim K9YC
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