At 07:41 AM 6/11/2009, Dick Green WC1M wrote:
>Wouldn't do any good with my coax lines because the Polyphaser coax
>suppressors at both ends don't pass DC. Would be good for the rest of the
>stuff, but it would be a major project to build cables to ground the nearly
>200 wires and would double the time it takes to unplug everything. One of
>the reasons I built the panel the way I did was to make everything
>accessible in one place, quick and easy to disconnect, so there would be no
>disincentive to do it. Hopefully, the suppressors will do their job and
>clamp the voltage of the surge below the level where it would jump from the
>panel to nearby ground.
For whatever another anecdote may be worth, my station is on the
second floor in an old house, and for that reason I concluded long
ago that the classic Polyphaser approach would be a waste of money,
because I could not achieve the ideal SPG configuration, much less
have a low impedance from the SPG to earth ground. I know some
people say they leave their stuff connected all the time, get hit all
the time, and never have damage, but I would never be comfortable with that.
I am using a very simple disconnect panel in a double-hung window,
with 3 Cinch-Jones connectors, two DINs and 4 coax connectors. My
disconnected cables are held on the window-sill a few inches from the
jacks into which they plug.
Three years ago I suffered a direct hit on the top of my tower during
a very violent thunderstorm, with all cables disconnected at the
entry. I was in the shack at the time, and heard a very loud "snap"
as the coax connectors arced to ground through the entry panel, but
that was the extent of it. Nothing jumped to the disconnected
cables, and no damage was done that could be traced to them - in
fact, the damage in the house (computers) was solely traceable to
induced voltage on a network cable and internal telephone
lines. Every active electrical device on the tower - two rotators, a
stackmatch and an antenna relay box - was fried, but no surprise there.
As I said, for whatever it's worth.
73, Pete N4ZR
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