Tom Donaly wrote:
You can still pretend a dipole is a "linear system," as you
call it, and still understand that the current envelope is not
a simple sine function.
Diverting to a "simple" sine function in the same spirit as
diverting to a "small" loading coil?
If you were always talking about a perfect sine wave, you should
have said so long before now and nobody would have disagreed with
you.
The Achilles heel of all your reflection
mechanics ideas is the assumption that everything is lossless.
That's NOT the assumption. The assumption is that lossless systems
are easiest to understand so let's understand them first before
we move on to something more complex. You guys have proven that
you don't even understand the simple lossless condition.
(Not to mention the fact that it's supposed to exist in outer
space.) You and Reg like to think of a dipole as a transmission line,
and Reg can even tell you its characteristic impedance (average). What
neither he nor you ever mention is the alpha part of the
propagation constant. That's the important part, though, since it
signifies radiation, the very thing the antenna was designed to do.
Only about 1 dB of the steady-state energy stored in a 1/2WL
dipole is radiated so radiation is not the largest effect. The
radiation from an antenna can be simulated by using resistance
wire to simulate a 1 dB loss in a transmission line. The reason
that I have rarely mentioned such is that you guys don't understand
enough of the basics to proceed to those more complex examples.
By the way, why are you quoting from a network theory book when not
too long ago you were ranting and raving about the invalidity of the
lumped constant model?
The lumped constant model is valid under certain conditions. What I
object to is its use under known invalid conditions. The lumped constant
model and distributed network model are both *linear systems*.
--
73, Cecil
http://www.qsl.net/w5dxp