Hi Garry,
what you are saying is not true. The MFJ-1025 noise canceller does not
"noise cancelling" but "beam forming". The two antennas (one MAIN and one
AUXILIARY) are used by gain and phase adjustment to form a 2 element beam,
where the diagram is a cardiod, i.e. is has a null in a variable direction.
This is useful to null out an interfering (ground-wave) signal which can
either be noise or an interfering station.>>>>
That is one way it works when the noise canceller is fed signals from two
equal pattern antennas spaced 1/4 wl or less. In this case it can cancel
noise from multiple sources in the same direction at large distances.
That is not how it works when a noise sense antenna and receiver antennas
have greatly dissimilar patterns and dissimilar sensitivity to noise, or the
antenna are in nearfield of noise. In this case they normally only work when
the noise is from one source (like an arc in an insulator), even if that
source radiates from many points or directions (like a long wire connected
to that insulator that circles your house).
It can work by either method.
73 Tom
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