Your station should operate successfully with only the equipment bonded to
the power supply and that attached to an outlet with a solid 3rd pin ground.
If it doesn't then you have antenna and feedline issues that should be
addressed. Any RF in the shack should be the result of radiation from the
antenna. With a properly configured system, this should cause no concern
for RFI or RF issues.
The only RF in my shack is that which is radiated by the antenna. Secondly,
don't confuse lightning protection with power system ground or RF ground.
If you think in any way or implement any system inside your house or
building directed at lightning protection, you have a dangerous system where
it is highly probable to cause a fire due to a lightning strike. Please
evaluate your system carefully as your equipment, your house and your life
depends on it.
73
Bob, K4TAX
----- Original Message -----
From: "Martin Ewing" <martin.s.ewing@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, April 04, 2009 10:52 AM
Subject: Re: [TenTec] RF Ground
Yes, but... It's still worth trying to establish a local RF "ground" --
ensuring that everything in your shack is bonded together. No antenna
system is perfect, and many of us have some RF in our shacks.
Fortunately,
the same bonding is needed for lightning and AC safety reasons, although
inductance is not a worry at 60 Hz.
The ideal is a Faraday Cage - enclosing your shack in a (nearly) solid
conducting box.
73 Martin AA6E
On Sat, Apr 4, 2009 at 12:35 AM, Jim Brown
<k9yc@audiosystemsgroup.com>wrote:
>
> Do recall that any station ground has length and inductance and
impedance.
> It may be a good DC ground as it has low resistance, but is it a good
> RF
> ground? In almost any condition, the station is above RF ground. For
> example, a station ground that is some 16 ft in length puts the station
at
> 1/4 wave above ground on 20M. That 1/4 wave ground wire can radiate or
> receive noise just like an antenna.
>
The words "RF ground" have NO MEANING in science. They are a fignewton
of fuzzy thinking. A connection to EARTH is totally irrelevant for a
radio transmitter, receiver, or antenna. A connection to earth is NOT
part of a solution to RF interference, hum, buzz, or noise. A
connection to earth does not make an antenna work better. It only
provides lightning protection. That's very important, of course, and
to do that, ALL ground rods must be bonded together by that low
impedance path, and all wiring that enters a building must have its
lightning protection bonded together and to that network of ground rods.
For two reasons, that bonding together also minimizes hum and buzz
related to the power system.. First, pin 1 problems. Second, unbalanced
wiring. Both couple noise current into equipment.
The EARTH is a LOUSY antenna element, because it is lossy (resistive).
Any RF current flowing in the earth is lost as heat. We use radials with
vertical antennas to prevent current from flowing in the earth, and
allow it to flow in low resistance copper instead. The vertical antenna
is trying to produce an EM field, and the radials complete the path for
that field (and for the antenna current). Only a few resonant radials
can serve that purpose if they are high above the earth, but it takes
MANY radials to do that well if they are very close to the earth. Those
radials are not RF GROUND. Over the years, we have confused ourselves by
calling them a ground system, or a "ground plane." They are not. They
are part of the antenna!
73,
Jim Brown K9YC
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