After the sage advice of two TowerTalkians, I have decided to do it right:
Single Point of Entry. Because of the importance of this matter, I include
both received comments verbatim. I also received a request to summarize.
Thanks es 73, Jim, VE1JF
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The first goal is to have a single cable entry point with lightning
protection on all lines entering, AND a LOW resistance LOW inductance
bond to the lightning protection earth electrode system as well as a low
R/L to other cables penetrating the house at other locations.
If the first goal can not be achieved, ALL penetrating cables
must have lightning protection and have their shields bonded together
with a LOW resistance and LOW inductance electrical bond.
This LOW R/L bond is SO much easier if all of the cables are near to each
other.
Maintenance, testing, and inspecting at a single enrtry point is also
easier.
During a lightning strike, ALL points need to be at the same potential.
The higher the resistance in bonding jumpers, or the higher the inductance
in the same bonding jumpers, the higher the potential difference.
The high potential difference, DOES THE DAMAGE to equipment in the shack.
The single entry point IS the cost effective solution to most
installations.
Good luck in your installation.
Stan, WA1ECF Cape Cod, MA FN41sr
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I am given to understand that if the two entries are separated by 75' or
more, there will be little effect as long as you have a full "perimeter
ground" around your structure. If you are like most hams, you don't. I am
facing the expansion problem , but luckily I can bring all the new stuff to
the same location. I do wish I had bought the larger Polyphaser panel,
though.
73 John N5CQ
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