IMHO a wire 1/4 wave length long wire should preferably be electrically
connected to the tower and fed from the bottom of the slope against a
good ground system. AM stations that have done this in emergencies
report good results.In fact some consulting engineers were so impressed
after making F/S measurements they have tried to get this method
approved as a simple way to take advantage of the directional qualities
in the direction of the slope instead of the expense of a two tower
array and phasers. These stations needed only a few db's of
cancellation of the rear side of the tower. Of course the FCC said not
because this method was too unorthodox for them to deal with. But the
concept does work with a slight bump in favor of the slope direction.
This is merely a way of shunt feeding a grounded tower that can allow
for the slant to be brought close to the ham shack where an ATU or
matching network can be placed.
Herb, KV4FZ
On 3/8/2014 10:41 AM, Tom W8JI wrote:
Has anyone modeled the 1/4 slopers? Perhaps the Alpha Delta DXA?
The pattern and performance of a 1/4 wave sloper is extremely
dependent on the tower and what is on the tower, the guy lines (if
uninsulated), and even how the tower is grounded.
There are very common cases where it won't work at all, cases where it
works fairly well, and everything between the two extremes.
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