To: <towertalk@contesting.com>
> Date: Thu, 30 Apr 1998 10:54:55 -0700 (PDT)
> I had a 4 element yagi at 120 feet and noted some rain static. I
> changed it to a 4 element quad and the rain static went away. Of
> course the QRN from a local power line was the same.
That isn't surprising. The yagi has points with high gradients (the
tips) sticking out into the air, while the quad likely has a long
flat sides all pulled in close to the tower.
I would expect the quad to have less corona, and the corona it does
have would not be at the highest impedance part of the antenna where
energy is coupled more efficiently.
However, the yagi could be cured by adding a large BLUNT conductor
vertically that removes voltage gradient between the lower yagi
elements and surrounding air.
None of this has anything to do with a closed DC loop or DC ground,
however. You yagi could be cured by adding smooth round balls to the
elements. (no viagra jokes please ;-))
73, Tom W8JI
w8ji.tom@MCIONE.com
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