Please note the following correction to my description of the I.C.E.
surge protector:
It consists of a large discharge inductor on the antenna side which provides
the primary protection and static discharge path. The arc tube is across
the inductor and serves to extinguish any back-emf due to the inductor.
The circuit then contains a SERIES hv blocking capacitor and a
SHUNT 150K resistor as a static drain on the rig end. (pardon my
previous dislexic posting!)
The I.C.E. literature asserts that gas discharge units usually have only
a small dissipative power rating of 1 watt or less which means that they
can only handle large jolts for a few microseconds. Used alone, these
protectors can't provide total protection - they must be used in conjunction
with a properly installed bulkhead ground system which shunts incoming surges
to ground before they reach the protector and other equipment. Since 80% or
more of an induced or direct hit usually comes in on the Shield of your
coax, all shields should be grounded at the base of your tower as well as
at the house entry. I also have a bakelite patch-panel next to my desk so
I can conveniently disconnect EVERYTHING including Beverages and control
cables. The other junk (protectors etc.) is just for peace of mind in case
I ever forget to disconnect everything (AGAIN!).
73 N6CQ/3
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