Gary, K9AY wrote:
"I prefer to think of a radial system as an approximation of a solid sheet
rather than individual conductors."
Tom, W8JI wrote:
"Why does the current need to be in any particular direction
Rick? That buss, assuming you have 50 radials or more, has a
pretty low termination impedance for the small currents in
the radial. While it may not be the shortest path possible
to a distant area because of the angle, it is a pretty large
path with a low impedance."
*************************************
I think now I better understand the "buss wire" connection. Suppose there is
an EM field that wants to drive a tangential current in a dense radial field on
the ground. A current could actually flow back to the junctions of the radials
and out again. The parallel components of the current could cancel, leaving a
net current in the tangential direction.
The foregoing is naive, since it does not take into account inductive or
capacitive coupling between the radials. I expect the coupling would enhance
the solid disk effect.
It would be fun to simulate this. If only I had a copy of NEC4.
If the radial field is like a solid disk, it only makes sense to truncate the
overlapping portions.
ON4UN in his book often refers to a radial field as a screen. That seemed
strange to me. I thought a screen would need to be a mesh or a solid sheet.
Again, if the radial field approximates a solid sheet, the screen idea makes
sense.
So, if I have a dense radial field for my 160M vertical, perhaps I won't need
as many radials for my 80M four-square supported from the vertical?
Mike W8GT
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