Antennas *are* circuits. Circuits can consist of either lumped or
distributed components, or both.

However, that's not particularly relevant to my point. In the steady
state, there is no test which can be devised that can distinguish an
antenna (including feedline, if desired) from a black box containing
lumped components -- a lumped component circuit(*). This allows us to
simply design such things as matching networks without any consideration
of the real properties of an antenna. Only when transient signals are
involved is other than simple lumped-network analysis necessary. In a
typical antenna and feedline system, steady state is reached much, much
faster than even the fastest CW dit or speech component, so transient
analysis isn't required for these common modes of operation. There are a
few familiar situations where analysis under normal operating conditions
requires consideration of the distributed nature of the system, such as
when doing time domain reflectometry or in some situations involving
television signals, both modulated and baseband. None of these, however,
can be considered steady state so the simplified model isn't applicable.

Cecil, if you feel a need to expound yet more on your theories, please
do so in one of the many threads you've come to dominate already, start
a new one, or concentrate your efforts on your forthcoming QEX article.
I hope you'll let us try and make an objective and hopefully helpful
contribution from time to time on this newsgroup without your constantly
attempting to steer the discussion to your theories.

(*) Furthermore, if we restrict analysis to a single frequency, the
black box needs to contain only two components - a resistor and either a
capacitor or inductor.

Roy Lewallen, W7EL

Cecil Moore wrote:
Roy Lewallen wrote:

A radiator is a circuit.


Most antennas are NOT a circuit. Most antennas are distributed
networks.

Circuit theory doesn't work on distributed network problems.
That's why distributed network analysis was invented.