Topband: Balun or no balun

[Tom W8JI]

>I have put up a 160 meter horizontal loop fed with 30 feet of 450 ohm feed 
>line to my tuner.  I have a Radioworks 4 to 1 balun. I am considering 
>splicing into the feed line at 10 feet so I can run 20 feet of  coax into 
>the shack.  Thoughts?  I run a qrp plus on 160.
>

Hi Kirk,

Are you using the antenna on multiple bands? The best way to feed really 
depends on how you want to use the antenna.

A resonant 160 meter loop around 20-30 feet above the ground has a feedpoint 
impedance of around 50 ohms on 160, and about 80 ohms on 80 meters.  The 
antenna impedance isn't really high until 40 meters, where it would be 
resonant far outside the band and have a terrible mismatch to any feedline.

450 ohm line (which are usually around 400 ohms) is a needless mismatch for 
160 and 80, but would be better for 40 meters and up.

The 4:1 balun is the wrong impedance balun on any band for any feedline.

73 Tom