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Old April 10th 06, 03:54 PM posted to rec.radio.amateur.antenna
Richard Harrison
 
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Default Current across the antenna loading coil - from scratch

Tom, W8JI wrote:
"The ONLY thing that allows a conductor to have current taper along its
length is displacement current."

In a-c circuits, added to ordinary conduction current there is
displacement current, at right angles to the direction of propagation,
determined by the rate at which the field energy changes.

Also at right angles to the direction of propagation, and determined by
the rate at which energy changes, there is a changing magnetic field, in
addition to the changing electric field. Together the electric and
magnetic fields exchange energy and produce radiation.

Displacement current which is the a-c current through a capacitor, that
has no d-c conduction, is not the"ONLY" thing that allows a conductor to
have a current taper along its length.. A conductor can lose energy
through dissipation and radiation forever, not just relocate it
temporarily through storage in a reactance.

The dissipation line at the end of a rhombic antenna does not handle the
entire output of the transmitter at its other end. Most of the energy is
already radiated by the time it reaches the dissipation line.

Best regards, Richard Harrison, KB5WZI