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Old May 18th 11, 06:38 PM posted to rec.radio.amateur.antenna
John KD5YI[_5_] John KD5YI[_5_] is offline
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First recorded activity by RadioBanter: Apr 2011
Posts: 60
Default Transmitter Output Impedance

On 5/16/2011 2:55 PM, Cecil Moore wrote:
On May 16, 2:42 pm, John wrote:
But I have no need of reflections. The fact that a 200 ohm load appears
as a 50 ohm load at the input of a 1/4WL 100 ohm line takes care of all
that for me.


There's no argument/discussion about that. The question is: Exactly
what happens at the 50 ohm Z0-match to reverse the direction and
momentum of the reflected wave resulting in no reflections on the 50
ohm line? Hint: it is exactly what happens with non-reflective glass
where the 1/4WL thin-film coating cancels the reflections through
destructive interference. Why not alleviate ignorance by taking
advantage of those well understood facts of EM wave physics from the
field of optics?

micro.magnet.fsu.edu/primer/java/scienceopticsu/interference/
waveinteractions/index.html
--
73, Cecil, w5dxp.com
"Halitosis is better than no breath at all.", Don, KE6AJH/SK


By the way, what is the impedance of a constant 100W source looking back
into its short piece of internal 50 ohm line?

John