[TowerTalk] 75ohm cable
Jim Brown
jim at audiosystemsgroup.com
Mon Jul 19 22:39:17 PDT 2010
>True, but the additional loss in the coax depends on the matched loss
>and the additional loss (in the line) due to SWR. With a low loss line,
>it's miniscule, but if using RG8 on 440 it could be substantial.
WRONG! The additional loss due to mismatch does NOT depend on the
matched loss. It depends ONLY on the mismatch at the load. In fact, the
higher the MATCHED loss, the less that mis-match matters. One of the
things that the Smith Chart teaches us is that loss causes the SWR to
converge toward 1:1 (and the impedance at the TX to be equal to Zo. The
more matched loss, the faster it converges.
73, Jim K9YC
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