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Old February 28th 07, 12:33 PM posted to rec.radio.amateur.antenna
Jeff Jeff is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 158
Default tuner - feedline - antenna question ?


VSWR 4.75


A 200 ohm load on a 50 ohm line is 4:1 at the load end in my view, and it
is lower as you move toward the source.


Indeed; 4:1 decreasing to 3.2:1 at the source, BUT only when the source is
50ohms.

Change the source impedance to 100ohms and the picture changes to 5.5:1 at
the load and 4.75:1 at the source end.

By the way the vswr figures will change cyclically with frequency assuming a
fixed length of coax ( 5.35 wavelengths at a fixed frequency), between about
7.5 and 2.5 at the load and 7 and 1.5 at the source.

73
Jeff