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Old December 8th 07, 02:24 AM posted to rec.radio.amateur.antenna
Keith Dysart[_2_] Keith Dysart[_2_] is offline
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First recorded activity by RadioBanter: May 2007
Posts: 492
Default Standing Wave Phase

On Dec 7, 4:21 pm, Cecil Moore wrote:
Keith Dysart wrote:
You have said that 1, 2 and 3 from above are electically
90 degrees.


How about:
(6) 43.4 degrees of 600 ohm line, 180 degrees of arbitrary
line terminated in a lump of 0-j567. This is just another
way of placing 0-j567 at the end of the 43.4 degrees of
600 ohm line.


Of course, if you add 180 degrees you have added 180
degrees to whatever existed before. Do you disagree?


So this meets the criteria you originally proposed and
is an example of 90 degree electical length?

Can you provide a rule for discerning when a stub or
antenna is electrically 1/4WL long?


Of course! When the reflected wave undergoes a phase
shift of 180 degrees in its round trip to the end of
the stub and back, the stub is electrically 1/4WL long.
How can you disagree with that?


So (4), a short, meets this criteria. It did not have to go
far down the stub, but it did arrive back with a 180 degree
phase change. But previously, you did not include (4).

Is it now in the list?

....Keith