On Mon, 6 Oct 2008 16:28:21 -0700 (PDT), Bill MacLane wrote:
>A good RF ground system is bonded to the service entrance
>electrical ground rod for the same reason.
Horse pucky.
RF does not need a ground! Antennas do not need a ground.
Transmitters do not need a ground. Receivers do not need a ground.
A connection to the earth is NOT part of a solution to RFI
problems.
The ONLY reasons for a connection to EARTH are 1) lightning
protection; 2) a termination for the Faraday shield of a
transformer to prevent coupling of power line transients to the
facility. #1 is the most important by far. #2 is VERY secondary.
SOME antennas (mostly verticals) need to work against a
counterpoise or radials. This has NOTHING to do with the earth.
The field radiated by antennas bounces from the earth, and is
reflected in useful ways to form its vertical directivity. Some
forms of propagation involve the travel of radio waves along the
earth. None of this involves a CONNECTION to earth.
Bottom line -- THERE AIN"T NO SUCH THING AS AN RF GROUND!
73,
Jim Brown K9YC
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