[TowerTalk] noise canceling

[VR2BrettGraham]

WD4K's post on experience with MFJ box very much like
my experience with ANC-4 here.

Pretty much can cancel out anything I can pick up with
a decent sense antenna - even sea surface radar coming
from a hop away.

Having said that, watch out for these things wilting on you -
they really could use some selectivity, as not happy with
heaps of out-of-band energy (perhaps not a problem in NA).

73, VR2BrettGraham