[Towertalk] single point ground

[jljarvis]

Bill,

First, you need to recognize that the 2nd floor windows are too 
far from ground to be of value.  What you do there is cosmetic,
and weather seal only.  

Second, in addition to providing a ground panel at ground level
for antennas and control cables,  on the downstream (station) 
side of them, I would route all cables through a piece of iron
pipe about 4' long.  Ground it, as well, to the single point.

It will act as a choke for transients which get across the
ground panel, forcing arcs to ground at the SPG.

I am assuming that what you do at the SPG provides an ESD gap,
so excess voltage is dumped to ground across all coaxes and
rotor/control cables.  ICE does this.  

rgds, Jim, n2ea



In a message dated Tue, 23 Jul 2002 12:28:24 PM Eastern Standard
> Time, Bill@aa6tt.com writes:
>
> > I am considering removing a window in my garage (my ham station
> > sits on the 2nd floor, over the garage) to use as an entry point
> > for all my antenna feedlines and control cables.
> >
> > I am thinking of replacing the window with a sheet of copper cut
> > to the window frame's dimensions, drilling a series of holes for
> > double female coax feedthru connectors to connect the feedline
> > from the antenna outside the window to ICE lightning protectors
> > (the ICE units connected to the feedthru connectors via double
> > male coax connectors) on the garage side.  Copper ribbon will
> > connect the copper sheet to a series of ground rods (and the
> > telco and power gnd systems).
> >
> > I'm looking for comments on this setup before it's built.  Should
> > I be concerned about bolting the copper feed thru panel
> > directly
> > to my garage's wood frame -- is this a fire hazard?
>