On Wed,9/10/2014 8:11 AM, Bill Turner wrote:
I'm curious why this is.
Time spent on N6LF's website will yield great rewards. He's done
extensive research on radial systems for 160M and HF verticals.
http://www.antennasbyn6lf.com/
A good starting place is his QEX article on elevated radial systems.
Also -- several years ago, I hung two sloping vertical wires off of
either side of my 120 ft tower (insulated at the top) and fed them at
the bottom against four radials elevated about 6 ft. The antennas had
the directivity that NEC predicted (roughly 6 dB F/B in the direction of
the slope), but not the gain. A while later, I chatted with N6BT about
this, and he said that they were too low, and that 18 ft was a minimum
height for 160M. I raised them (gull-wing style) and the gain improved a
bit. Don't ask me how much they improved -- that's VERY difficult to
measure. :)
73, Jim K9YC
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|