Earl, K6SE wrote:
>
> ... I assume that some are interested in decreasing local man-made
> noise levels coming from a specific direction.
Equally deep nulls can be obtained with SLIGHTLY off the maximum
F/B ratio (which produces two nulls). Then the wider null can
do a better job of eliminating NON-point source interference such
storm related static and local QRM (my main concerns) as well as
man-made noise. A test last night showed a W7 going from S-7 on
the S-meter on the 264 degree Beverage to no meter movement at all
on my 30 degree Beverage. That, on a wide range of signals as well
as static, is my goal in Beverage design...
> The termination resistor value in the models which results in best
> F/B also happens to result in max forward gain and lowest reception
> angle, both of which are good indicators of best directivity,
> therefore lowest noise, no?
Given that the main lobe barely changes at all when the null area
changes signicantly, I worry about the several dB changes in the
nulls more than the tenths of a dB changes in the main lobe on
receive antennas.
Hopefully my suggestions are seen in the helpful tone that they
are meant. Maybe it's due to my incorrect interpretation, but
other reflector notes appear to border on the hostile side. I'm sure
that I've also been guilty of the incorrect choice of words which has
made a planned simple statement of comments sound confrontational or
boastful. I apologize if that's ever been the case...
73, Bill K0HA
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