I dunno if I buy those arguments. I would tend
to think that even if the powerlines are reradiating
energy from a single discharge point, the vector
sum at your receiver should still looks like a single
source provided that the relative delays of the
mutliple sources aren't on the scale of the
modulation frequency (60 Hz/16ms) or the r
eceiver bandwidth (3 KHz/330us).
Instead I would suspect that the noise
cancellors are failing because the afflicted
lines have multiple discharge sites that aren't
time correlated. The zero crossings in different
phases of a 3 phase system for instance are
about 5ms apart and that's if they are at the
same physical location. Just imagine dirty
insulators in opposite phases and different
physical locations of a 3 phase power
distribution system. Reconstructing the weighted
sum of those two noise sources exactly at your
receiver would be next to impossible without
a lot of trial and error.
Of course I could have this all wrong. I
am off in theory land again.
73 de Mike, W4EF............
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