Topband: Common Mode Noise

[Ralph Matheny]

In my experience anything that you can do that prevents noise from
being conducted thru the wires in the area of your antennas will help
you to hear weak signals in some case some time.  Thus, it is my
notion that "common mode" filters at the power entrance box would be
especially a good idea--hopefully preventing noises from down the street
from being re-radiated by the power wires in the house.  Such filters
at the radio bench might even create "ground loops" which degrade 
reception, depending upon how grounding is handled.  It's a case for
giving it a try and hearing what's best.

Even with all the (known) appliances in my house turned off, I can
clearly hear the "house" from my flag antenna system 150 feet away.
If I pull the "main" breaker and listen on a battery operated radio,
the noise from the house wiring goes down or perhaps away.

Anytime currents flow in a wire--expect at least some signal to be
radiated.  If one can limit the currents in the area of his antennas to 
those which are necessary and desirable, it sure can't hurt.

Ralph Matheny
K8RYU
207 Gibbons Place
Marietta Ohio  45750