> There are three different [primary] currents in effect beneath and
> around a vertical radiator operating over earth and above an
> artificial ground plane. These are (1) conduction currents, (2)
> induced currents, and (3) displacement currents.
Displacement currents are fictitious currents that were "created" or
invented to explain how current flowing into one lead of a capacitor
manages to flow out of the other lead, without charges actually
moving through the dielectric.
Somehow we have taken that very necessary but imaginary concept of
"invisible current" in capacitors and applied it to actual physical
currents in conductors or poor insulators, like earth.
Make no mistake about it, charges that are "moving" in earth or in
conductors of any form are very real currents, and we can not sort
those currents out any differently than any other current or moving
charge.
"Displacement current" can push our concept of losses in an antenna
system into the twilight zone real fast, as is evidenced by many of
the wild theories that sound good but never work that are advanced
over the years.73, Tom W8JI
W8JI@contesting.com
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