Richard Harrison wrote:
"Displacement current which is the a-c current through a capacitor, that
has no a-c conduction, is not the "ONLY" thing that allows a conductor
to have a current taper." It was Tom, W8JI who shouted: "The ONLY thing
etc." I just said displacement current is NOT the only thing. Energy
level often declines between ends of a wire or coil due to losses from
radiation or dissipation in the wire or coil. Tom is mistaken.

Sorry Richard, that is not correct.

Radiation does not cause current taper. Dissipation does not either.

Consider dissipation first. If dissipation caused current reduction,
the return to a battery from a light bulb would have less current than
the outgoing terminal. There has to be a third path to allow current to
divide, but the totals of the division equal the initial amount. That's
a rule we learn way back in basic electricity. Current or charges are
not converted into heat.

Radiation is no different. Radiation is not conversion of charges into
a force that allows action at a distance. Radiation is a force on other
charges at a distance caused by charge acceleration.

The only thing that allows an antenna to have current taper or current
change along the length of a wire suspended in space is displacement
current. It is not standing waves, it is not radiation, it is not
resistance.

Of course we could add a shunt resistance or inductance to provide a
path, but when there is no leakage resistance or shunting inductance
the path can only be what is called displacement current.

A series impedance or resistance by itself, even if the cause is
radiation or loss resistance, cannot cause current reduction with
distance along a conductor.

A model that only considers reflected and forward "waves" is fine, if
applied correctly. Cecil doesn't even seem to understand current, and
appears to think there is a forward current and reflected current
moving in opposite directions at the same instant of time in the very
same location in a conductor.

Wave theory is just fine, but it has to be understood it is just a
modelling shortcut and the results cannot conflit with basic laws of
physics. The current we measure with a clamp on meter IS the current
that causes radiation, standing waves or not. It is also the current
that causes all of the heating. We cannot really have two opposite
directions of charge movement at the same time in a single conductor.

73 Tom