> > Whith this level of protection, would you still install coax and rotor
> > cable protectors at the shack entry too? If I was only going to have
> > one (relatively) "extensive" ground system, do you think it makes much
> > whether this is at the tower or shack end.
According to the Polyphaser book (and the ARRL Antenna Book), you should
have coax and rotor protectors at both ends of the line. I think the
reasoning is that a lightning stroke can induce current in the cable runs
between the tower and shack, even if they are buried. If the cable runs are
long, the protectors down at the tower end will not protect your equipment
in the shack in this case.
The Polyphaser book also recommends an "extensive" ground system at the
tower end. The idea here is that you want a hit on the tower to be absorbed
at the tower end, not the shack end. So you have the right idea by putting
your big efforts into the ground system at the tower.
At the shack end, all cables should pass through a copper bulkhead panel or
be connected to an entry panel to which the protectors are mounted. The
panel is grounded to a rod as close to the panel as possible. The panel is
the "single-point" ground to which all your shack equipment and phone line
protectors should be connected as well. I believe you can use more than one
ground rod, although the diagrams usually show just one. Ideally, the ground
rod is attached to a perimeter wire that encircles your house and is
connected to the utility and phone ground rods.
73, Dick WC1M
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