[TowerTalk] Mismatch Loss and Tuners

Pete Smith n4zr@contesting.com
Mon, 24 Aug 1998 19:18:11


Steve wrote :

[much deleted]

SUMMARY -  A matched antenna will significantly outperform a 
     mismatched antenna with a tuner.  A tuner cannot introduce "reflection 
     gain" to change this fact.

This whole discussion is a semantic thicket.  To ease my brain, let's
consider a specific case. A 1/2 wave dipole, at its resonant frequency, fed
with 600-ohm open wire line, matched to the transmitter with an appropriate
LC circuit (including balanced-to-unbalanced transformation) at the
transmitter end.  Assume that the antenna has a feedpoint impedance of 50
ohms resistive.  

Compare to the same antenna fed througha balun with 50-ohm coax, matched to
a 50-ohm transmitter.  Will this second antenna "significantly" outperform
the first?  By how much?  Where do the losses occur? 


73, Pete Smith N4ZR
n4zr@contesting.com 

"That's WEST Virginia.  Thanks and 73"

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