[TowerTalk] ground losses (vertical antennas)

[Tom Rauch]

> On the one hand, the vertical is often depicted sticking
up out of the
> ground and having dotted rays of antenna current (field?)
flowing out
> from it on their way to ground and back through ground to
the source
> connection.

The dotted lines are "displacement currents". The represent
the imaginary current flowing across a capacitance.
Displacement currents are the only reason (I can think of)
that current tapers in an antenna. Of course once they are
in a conductor, like earth, we probably should not call them
displacement currents.

ALL of the current that flows into the antenna has to be
matched by exactly equal current from the other terminal,
the earth (or whatever the couterpoise is).

> On the other hand, what bothers me is that current flowing
back
> through ground must be equal to the current flowing into
the
> antenna and thus radiated.  It seems the radiated current
from
> the antenna is split.  Part goes into space and part goes
into ground.
> If the ground resistance is reduced it would seem that
more of
> the antenna current would go into ground and less into
space?????

Current does not radiate off into space. Charges are not
moving in empty space.

Charges are moving in the lossy resistances of earth.

Try this:

http://www.w8ji.com/radiation_and_fields.htm

or related page links.