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Old March 16th 07, 02:22 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default VSWR doesn't matter?

Richard Fry wrote:
For example, a reflection from a mismatch between a 1,000 foot long,
air-dielectric transmission line and the TV transmit antenna connected
to it
produces a ghost with ~ 2 µs delay from the main image. The active scan
width of an NTSC TV line is about 53 µs, so 2/53 = ~4% of the width of the
screen, or maybe 5% counting overscan. This ghost is easy to see in a
typical TV set/viewing setup.


We performed that exact experiment at Texas A&M
in the 50's. The ghosts were right where the
reflected waves predicted they would be. I
wonder how the modulation in a reflected wave
moves up and down the line without the reflected
wave also moving up and down the line? :-)
--
73, Cecil, w5dxp.com