> > No.. sparks to the air. Tesla Coils, St. Elmo's Fire,
Airplane p-static,
> the
> > crackle of a charged Van deGraaff generator, and corona
discharge, are all
> > examples of what we're talking about here.
> >
> > When the charge on a conductor gets to where the E-field
at the surface
> > exceeds the breakdown voltage of the air, it will
breakdown and start a
> > leader (which typically dies out real fast, unless the
object is large, or
> > there's a continuing charge source). The production of
that leader heats
> > up/ionizes the air, the energy for which comes from the
charge on the
> object
> > flowing into the leader.
I don't agree.
If an antenna charges from collecting charges from the
surrounding air, how does it discharge to something of the
same potential? Corona occurs only because the clouds above
and around the antenna have a different potential than
earth.
It charges towards the potential of the air Jim, and
discharges to earth! That's why we use drain coils to earth.
That's one of the reasons why the utility companies ground
the open lines when doing service work, to prevent linemen
at ground potential from the shock if they touch a very long
wire that charges to the V/m field potential caused by the
height and the natural charge as we move above the earth's
surface.
73 Tom
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|