On 1/20/2013 1:40 AM, cx7tt@4email.net wrote:
I started replacing all items along the path and discovered the PP on
the grounded copper board at the base of the tower had gone 'south'...
Several points here. First, there is no value to lightning suppression
at the base of a tower unless that tower is next to the shack. A
lightning suppressor shorts the center conductor to the shield to
protect equipment that the coax feeds. It is most effective very near
the equipment.
Second, lightning protection depends very strongly on proper bonding
together of all the equipment and wiring in your home, to each other,
and to all earth connections. That means EVERYTHING. Caps for emphasis
added.
Third, while I have no practical way of knowing when Polyphasers have
failed "open," I have experienced at least four occasions of Polyphasers
failing shorted. On at least two of those occasions the cause of the
failure has been very high voltage at the Polyphaser, most recently
caused by the 40M element of my 80/40 fan breaking in a windstorm and
hitting with legal limit power before I had figured that out.
It should be possible to restore the Polyphaser to new condition by
replacing the gas tube if a source for the tube (including its spec) can
be found.
73, Jim K9YC
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Topband Reflector
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