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Old May 24th 04, 05:29 PM
Richard Harrison
 
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Mike, KB3EIA wrote:
"But the idea of signals being actually reflected seems hard to
swallow."

It`s true that antennas are measured in degrees. A 1/4-wave antenna is
90-degrees. This is based on how many degrees the signal has changed at
the antenna input by the time the signal reaches the tip end of the
antenna.

When signal reaches the end of a 1/4-wave whip, there is an abrupt
discontinuity. Only displacement current flows without conductors. The
tip of the whip accepts only a small fraction of the current available
in the forward power traveling on the whip. The only path for the
rejected power is back toward the feedpoint. Direction and phase of the
current reverse in the reflected power, but the voltages of the incident
and reflected waves have the same phase (see 1955 Terman, page 89).

Best regards, Richard Harrison, KB5WZI