>however NEC bonds are NOT for RF and NOT for
>lightning dissipation.
I'll take several issues with that. First, NEC bonding to earth
electrodes IS specifically for lightning protection. That is the
purpose of an earth connection.
One function of NEC bonding between equipment enclosures is to
provide a path that will blow a fuse or breaker if there is a
fault that makes the chassis hot. Another function of bonding is
to cause all parts of the electrical system in a home to rise
together in the event of a strike, thus minimizing the DIFFERENCE
between equipment that might be interconnected. It is often this
difference that blows up equipment. Bonding everything together
approximately limits that difference to the voltage induced on the
bonding conductors.
Second, lightning IS RF. IEEE studies show that most of the energy
in lightning is in several octaves centered around 1 MHz (that is,
from about 250 kHz to about 4 MHz).
Third, there is no "RF" reason, other than lightning protection,
for a connection to earth. A connection to earth does not improve
the performance of antennas, it does not reduce noise, it does not
reduce RFI. References saying that it does are WRONG, including
statements in equipment manuals, ARRL publications, and even
several questions in the current license exam pool!
As to the bonding conductors themselves -- the primary problem
with braid and other small stranded conductors is increased
CORROSION if they are exposed to the elements. That's why they are
not recommended for these applications. There's nothing wrong with
using them if they are not exposed. I use braid for bonding inside
my shack because it is beefy and more flexible.
73,
Jim Brown K9YC
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