> carbonized thread types were known as "static wicks". They were
> attached to the training edges of the wings and tail to discharge any
> corona buildup on the aircraft as it flew through rain or snow.
The key difference between using them in the intended application
and the new application on towers and building is the size and
capacitance of what you are trying to discharge.
On aircraft, they only have to bleed off a well-insulated small object
with very little charge storage...the airplane.
When you place them on the earth, or an object connected to the
earth, they have to discharge the earth.
That is unlikely to happen in our lifetimes, because the earth is a
huge reservoir of charges.
> Presumably the static would discharge off of the static wicks rther
> than off of the radio antennas, thereby reducing the precipitation
> static noise in the radios.
That would work if the tower did not re-radiate the "noise" as the
corona flew off the discharges, and if the antennas were lower than
that corona stream or in it.
The whole problem centers around voltage gradient between our
antennas and the charge up in the sky. We have to somehow
reduce that gradient. One way is to lower the antenna, another is
to make it "blunt", another is to put something grounded above our
antenna and some distance away so it is the highest object and far
enough away we don't hear noise.
We had a repeater on top of a tall building that was fine, until they
installed "wicks" and one wound up near the antenna. Then we had
corona noise during every storm. We had to move the antenna far
away from the wicks and the nasty corona noise they made.
My Beverages pointed back towards my tall towers "hear" corona
noise quite well during storms, so I suspect you'd need quite a bit
of spacing on 160 meters.
73, Tom W8JI
W8JI@contesting.com
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