[TowerTalk] balanced line loss on a mismatched antenna

Paul Christensen w9ac at arrl.net
Mon Feb 27 15:48:08 PST 2012


> "I think I can tune the antenna with the feedline and get it down to a 
> more reasonable level, maybe 10 to 1, at the tuner end. Then the tuner 
> will tune it to resonance so the xmttr can put its full load into.
> Question is, since the swr is 10 to 1 at the radio end of the feedline but 
> 100 to 1 at the antenna end of the feedline, am I going to see the 3.5 db 
> loss from a 100 to 1 swr or the .5 dbi that a 10 to 1 swr would give me."

Gary,  you can vary the impedance at the input end of the line, but not the 
SWR.  The SWR on the 450-ohm section will remain nearly constant over your 
150 ft run, even with length trimming.

In EZNEC, what is the Z of the antenna you're modeling at the operating 
frequency in an R+j format?

Paul, W9AC 



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