Thomas wrote:

Sorry for the dumb question, but I see the phrase "RF current" used in
so many contexts that I am not sure what it is.

What I "think" it is, is:

1. The sinusoidal, voltage / current that is impressed on the, e.g.,
coax feedline's center conductor by the transmitter (a.k.a.,
generator)

No, current is not "voltage/current". It's current. Voltage is something
else. This comment applies to 2-5 also.

It also doesn't have to be sinusoidal.

2. The voltage / current on the conductive portion of the radiator

3. The sinusoidal, voltage / current that is picked up by the "other"
conductive portion of the radiator (e.g., other pole of a dipole or
the ground, radials or counterpoise system of a vertical antenna)

Now, the question is, how is that current "picked up"?


4. The sinusoidal, voltage / current that is returned to the
transmitter via the shield of the coax.

5. The induced voltage / current in the counterpart of the receiving
system.

6. The current that "flows" in a dielectric, otherwise known as
displacement current, the original notion that allowed Maxwell to
posit the existence of the ether.

That is, RF current is no difference than "current" except for its
frequency.

And the fact that it can "flow" through non-conductors as a
"displacement current". This can make its behavior a lot different than
zero-frequency current (DC).


What RF current is NOT is the transverse electromagnetic wave. That
is, once the effect is in the ether there is no RF current.

"Displacement current" IS an electromagnetic field. It's the mechanism
which induces conductive current in one conductor as a result of
conductive current in another. (This the answer to the question I asked
after point 3.)

Looking for confirmation or refutation of the specific points above.

Thanks.

Thomas

Roy Lewallen, W7EL