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Old March 13th 07, 10:39 PM posted to rec.radio.amateur.antenna
Richard Fry Richard Fry is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 440
Default VSWR doesn't matter?

"Owen Duffy" wrote
Richard,
The round trip time on the transmission line is 1uS+, and the period of
the highest modulating frequency is 0.2uS, so transient performance of
the line is very important.

____________

Sorry, sir, but quite a few decades of experience in the analog TV broadcast
industry show otherwise (not to mention an accurate theoretical analysis of
this condition).

For example, a reflection within an analog TV broadcast signal that is
delayed by one microsecond from the main image equates to something like a
10% horizontal displacement of that reflected, or "ghost" image from the
main image (525/60Hz TV standard).

A ghost television image amounting to 5% of the main image, and offset by
10% of the width of even a fairly small display screen is not difficult to
see (or to be objected to) by an "average" observer at an "average" viewing
distance from that display screen.

Reflected r-f power may be less of a concern to amateur radio operators than
it is to commercial operators, but that doesn't mean that reflected power is
non-existent, or even unimportant.

RF http://rfry.org