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Old November 16th 04, 05:53 PM
Ron Hardin
 
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Well of course hunting down mystery noise is fun too. But for
noise cancellers, the Timewave ANC-4 works great (formerly JPS ANC-4).

The best arrangement is use two external antennas, arbitrarily
connecting one to the ``noise antenna'' and the other to the
``main antenna.''

That gives you a two-element phased array, and you simply steer
its null over your noise source, and it's magically gone. This
is actually something of an entertainment itself.

You _might_ get by with the onboard noise antenna but that's more
speculative. It depends on how well indoor noise copies what the
outdoor antenna is hearing. Two real antennas always works better.

I myself have found this amusing enough to build an 8-element
phased array with 7 ANC-4's. Talk about versatile! I can
null two stations and hear a weaker third under them, with some
diddling, and have half the array left over.

The ANC-4 works down to MW and below, which the MFJ version does not.
MW is the most entertaining place of entertaining places to do
nulling and digging out.

Incidentally, for nulling distant stations, it doesn't work for SW
because the variability of direction of arrival with skip is bigger
than the size of the null you're steering; it works on MW though,
and at any frequency for local sources (ie with a stable direction)
like your noise source.
--
Ron Hardin


On the internet, nobody knows you're a jerk.