RHF wrote:
* The Justice AM Antenna is directional but not as directional
as a Select-A-Tenna Model 541-M; or a home made Box Loop Antenna
of about 15" or bigger.

All small antennas have the same nulls, the problem being that
they all have two patterns: a magnetic field pattern (with infinitely
deep nulls), and an electric field pattern (with infinitely deep nulls)
that doesn't null anywhere near the same place.

So in the nulls of the magnetic field pattern, you hear the electric
field signal instead of silence.

Careful balance and symmetry can eliminate most of the electric
field response, and that's how you get deep magnetic nulls.

If it's on the end of a long cable, it starts picking up electric
field again.

You can make it less important by having the first amplifier at the
antenna itself.

The passive MW loops work not by gathering signal (signal magnet) but
by matching impedance. Active ones work by having a lower internal
noise level than the receiver they front for.
--
Ron Hardin


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