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Old July 6th 15, 11:27 PM posted to rec.radio.amateur.antenna
rickman rickman is offline
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Default An antenna question--43 ft vertical

On 7/6/2015 4:50 PM, Ian Jackson wrote:
In message , rickman writes

The only case I am aware of that will give total reflection is when
the terminal is open circuit with infinite impedance absorbing *no*
signal.

Also when it is a zero impedance (short circuit).


I'm trying to picture this.

In the case of an open circuit a matched driver drives the transmission
line to 50% of the driving voltage. The wave reaches the open
termination and is reflected with the same polarity resulting in a
return wave that reaches 100% of the driving voltage.

In the same vein, if the wave hits the short circuit the reflected wave
will be the opposite polarity making the reflected wave 0% of the
driving voltage resulting in the short circuit eventually showing to the
drive circuit.

--

Rick