Thread: my SWR reading
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Old October 27th 07, 03:08 PM posted to rec.radio.amateur.antenna
Richard Fry Richard Fry is offline
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First recorded activity by RadioBanter: Jun 2006
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Default my SWR reading

"Roy Lewallen" wrote:
All the power produced by the transmitter arrives at the antenna
less whatever is lost as heat in the transmission line.


How about a case of a non-resonant transmission line whose Zo equals the
load Z except for a discrete mismatch somewhere in the line? Reflections
from that mismatch will be dissipated in the reverse port termination of a
circulator installed at the input of the line. Clearly not all of the power
available at the output of the circulator arrived at the antenna (less line
loss).

..Unless the line is perfectly matched, there will be repeating points of
high current and of high voltage. Depending on the nature of the conductor
and insulator, either or both of these can cause localized heating. In the
example you gave, the damage is almost certainly caused by high current
rather than high voltage. ...


I agree, and misunderstood your original post.

RF