Doesn't a good earth ground help remove stray RF from the shack? along with
ferrtie cores etc...
No. Any conductor carrying RF currents, not having another in close
proximity with equal and opposing RF currents, as in a transmission
line, produces RF radiation. A lead to a "good earth ground" carrying
significant RF current, will produce significant RF radiation. The key
to minimizing RF in the shack is to have all your transmission lines
working as transmission lines should, with equal and opposite RF
currents flowing in the two conductors (whether it is the coax center
conductor and shield, or the two wires in parallel wire line) so that
they are transmission lines and not antennas. There are various details
that need to be attended to to accomplish this. With good connectors, a
properly working transmitter, properly built cables and either a
non-radiating load (not very useful for communications, yet an essential
piece of equipment in every shack), or an antenna far enough away from
the shack and properly fed so that it does not induce unequal RF
currents into the two conductors of the feedline, there is no reason
that there would be RF in the shack. It is only when one or more of
those conditions is not met that there is a problem. Adding another path
for RF currents to flow, such as a ground wire, is probably just as
likely to make the problem worse as it is to make it better.
DE N6KB
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