Re: Loading Coils; was : Vincent antenna

On Fri, 14 Dec 2007 05:18:03 -0800, "Roger Sparks"
<rsparks@xxxxxxxxxx> wrote:

That IS what I said. Think of the velocity as a moving wall, with the
capacitor charged behind the wall, uncharged in front of the moving wall.
....
Be real. This experiment can be performed, and the DC switched as
frequently as desired. How square the wave front will be depends upon real
world factors.

Go to a transmission line characteristics table and use the formula to
compare Zo, capacity per length, and line velocity. It will amaze you.

Hi Roger,

Take a deep breath, exhale, give what's above some more thought in
light of many objections.

Now, tells us just what significance any of this has in relation to
already well established line mechanics? It certainly isn't different
within the confines of its limitations if that is what you are trying
to impress upon the group. I suppose for a mental short-cut it has
some appeal, we get too many theories here based on approximations to
stricter math. One such example is when an equation of approximation
has forgotten the underlying |absolute value| and suddenly an inventor
arrives with a "new" theory that discovers uses for negative
solutions.

Further, there is nothing DC about it at all. DC is either static
(and in spite of Arthur's corruption of the term, that means no
movement whatever) or it is a constant unvarying current. A
succession of distributed capacitors rules unvarying current out (and
if it isn't already obvious, those unmentioned distributed inductors
in one of your links do too) - hence the step, hence the infinity of
waves, and from this, real world dispersion which kills the step
enough to make that varying current apparent enough so as to remove
all doubt.

73's
Richard Clark, KB7QHC
.

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