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Old October 19th 04, 05:37 AM
Richard Harrison
 
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Tom Donaly, KA6RUH wrote:
"---forget what Richard just posted."

Suits me. You recall the old story about leading a horse to water.

Tom rejects measurements of r-f currents at both ends of a loading coil
at work. The currents were clearly differing.

Tom must be stuck with battereis and the rise and fall these produce in
the current of an inductor.

A loading coil is usually in the antenna field in our examples. The
loading coil is subject to an incident wave and to a reflected wave.
These waves combine in a continuously varying phase relation along the
coil to make current, impedance, and voltage all functions of their
positions along the coil. Every spot along the coil is different when
both waves are sensed together. That`s the way SWR works, and we`re
discussing standing-wave antennas.

I have a 1982 ARRL Antenna Book. On page 13-3 there is a Fig. 6,
"Improved Current Distribution Resulting From Center Loading". The
loading coil clearly shows less current at its top than at its bottom.

Best regards, Richard Harrison, KB5WZI