After reading this, I understand why you find Art's material interesting.

But, what's a "wave"?

Roy Lewallen, W7EL

AI4QJ wrote:
"Roy Lewallen" wrote in message
...
Just what is a "wave", anyway? Are there different "kinds" of
electromagnetic wave? If so, what are they? Does a "wave" have to travel
in order to be a "wave", or can it just "vibrate" or "oscillate"? Or just
"stand"?

Most of my references call a standing wave a "pattern". Is a "pattern" a
"wave"? Can a "wave" be a "pattern"?

That should be good for another few hundred posts, at least. Sheesh.

Roy Lewallen, W7EL

Roy,

The standing wave is the mathematical sum of the forward and reflected
waves. This sum is a superposition wave. The components of the superposition
wave no longer exist by themselves; they form part of the summation which is
the non-traveling "standing wave". Like its forward and reverse components
(each containing "real" power) that would have been traveling waves prior to
superposition, and which have now ceased to exist, the summation wave is
also a real wave that vibrates at a frequency that, when multiplied by its
wavelength, equals c (but traveling nowhere), and stored with "imaginary" or
"reactive" power, where the real power components have been changed to
reactive power components. Energy is conserved. The real energy in the
traveling waves has been changed temporarily to potential or reactive VA
(Cecil calls it VAR....same thing) energy until it dissipates into the
radiation resitance by the radiation of photons/waves through free space
(ignoring ohmic losses which also dissipate real power). After dissipation
of each photon or wave into free space (where E=hf, take your pick) from the
theoretical radiation resistor, the generator (transmitter) source must
replenish energy into the antenna to keep the standing wave stored-energy
system oscillating and then depleting into radiation. Without constant
replenishment from the generator, the standing wave diminishes to zero.

It is like an inductor, capacitor and radiation "resistor", all connected in
parallel, and whose impedance is the radiation resistance of the antenna,
which itself is related to the impedance of free space and the geometry of
the antenna (as you know). What is not intuitive is where the other terminal
of the "radiation resistor" is connected. But that is indeed where the
traveling wave from the dissipated standing wave 'travels' to. That is where
I find Art's material interesting. I do not think I have ever seen a
depiction of this phenomenon that can be conceptualized but I think Art is
trying.

OK, go ahead. Lock, load and fire ;-)

AI4QJ