[TowerTalk] Shunt Feeding a LARGE tower?

[Jim Brown]

On 1/25/2013 9:34 AM, William Powell wrote:
> Anyone out there ever try to shunt feed a LARGE tower on 160 / 75?
>
> By LARGE I mean a 200' - 250' free-standing 30' face tower covered with 3' - 8'
> dishes and a plethora of fiberglass omni sticks.

Almost ten years ago, I had the use of a similar tower, about 150 ft, a 
decommissioned AT&T Long Lines site on a mountain top. I chose the 
option of hanging sloping dipoles off the tower and feeding them from 
the center. The tower was tall enough that I was able to hang a dipole 
that was a full half wave on 80M and had loading coils with about 25 ft 
of additional length for 160. It worked VERY well. I was able to work 
anything I could hear with 100W during a CQ160CW, and the site was dead 
quiet, so i could hear a LOT, The bottom end of the dipole was about 10 
ft above the ground. In this sort of arrangement the tower acts as a 
passive reflector, yielding a few dB of gain in the direction of the 
sloping wire.

73, Jim K9YC