Let's take the case of a 50 Ohm line and some mismatched antenna. The result is
a combination other then 50 Ohm with most likely a zero complex component. All a
tuner does is match 50 Ohm at the radio to the complex impedance presented to it
at the source of the line.
That the only place with 50 Ohms and zero inductance in the line - antenna
system. The combination of cable and antenna presents something other then R =
50 ohms 0 reactance and the the transmission line see discontinuities. The
result is it radiates.
Dan
Cecil Moore wrote:
dansawyeror wrote:
Since you are talking about 50 Ohms I assume you are talking about a
transmission line. If that is the case you should definitely match the
feedline to antenna at the antenna feed point.
Why is it definite? What is the loss in 50 ft. of LMR-400 at the
frequency of interest when the SWR is 50/8 = 6.25:1?
Any attempt to match the feedline with a tuner in the shack only turns
the whole feedline into part of the antenna system.
Simply not true if the currents remain differentially balanced.
SWR doesn't cause feedline radiation.
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