Current across the antenna loading coil - from scratch
Gene Fuller wrote:
"This is incorrect, and even Terman never said such a thing."
I had written:
"Displacement current which is the a-c current through a capacitor, that
has no a-c conduction, is not the "ONLY" thing that allows a conductor
to have a current taper." It was Tom, W8JI who shouted: "The ONLY thing
etc." I just said displacement current is NOT the only thing. Energy
level often declines between ends of a wire or coil due to losses from
radiation or dissipation in the wire or coil. Tom is mistaken.
I don`t find the subject of "displacement current" listed in my Terman`s
index. I think its definition is accepted. but I gave mine in case
someone did not understand what it is.
J.C. Maxwell unlocked the secret of radiation when he speculated
displacement current would produce magnetic lines of force the same as
conduction current does, thus a traveling E-field produces an H-field
and vice versa. It`s been proved correct.
Terman writes on page 1 of his 1955 edition:
"Electrical energy that has escaped into free space exists in the form
of electromagnetic waves. These waves, which are commonly called radio
waves, travel with the velocity of light and consist of magnetic and
electric fields that are at right angles to each other and at right
angles to the direction of travel."
Terman writes on page 866 of his 1955 edition in his chapter on
"Antennas":
"A wire antenna is a circuit with distributed constants; hence the
current distribution on a wire antenna that results from application of
a localized voltage follows the principles discussed in Chapt. 4,
(titled"Transmission Lines") and depends upon the antenna length;
mesured in wavelengths; the terminations at the ends of the antenna
wire; and the losses in the system."
Nothing I wrote conflicts with Terman. That`s not the kind of fool I am.
Best regards, Richard Harrison, KB5WZI
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