[TowerTalk] Utility GND / Tower GND interconnection question

[Tom Rauch]

> Remember that the primary function of lighting protection
is to discharge the
> buildup of charge so that it is likely to arc and get
destructive.
>
> Note that I didn't suggest routing the strap through the
house, but in the earth
> under the house. In other words, the most direct path.

My house has the service entrance maybe 20-40 feet from the
radio room cable entrance, on an opposite wall of the house.

1.) All of my power and telco feeds into the radio room are
brought to a point at the cable entrance. All are common
there.

2.) A wide copper flashing runs UNDER the house laying on
the dirt between the utility entrance and the shack ground.

3.) A large buried copper buss circles the entire house and
everything is bonded to that buss, including the TV tower.

Despite having silver-soldered connections and bolted
connections and ZERO polyphasor or other things in the RF
and control line part of my Ham shack (I do have a few MOV's
on my power lines, zip on telco except RF chokes and
bypasses), I simply don't have damage inside the house. It
doesn't happen. I don't have problems with modems, TV sets,
or anything else and my towers get hit a few times a year.

A recent large discharge on my 300ft tower melted the telco
lines leaving my house, but the only damage inside the house
was the TV screens were all magnetized.

This is all because everything sensitive inside the house
has common grounds and RF common mode chokes. The TV sets
for example have those "surge strips" that ground the
antenna cables to the power line ground, and everything in
the cabinets plugs into those strips.

Since everything is spread around, it's really a multi-cell
concept. Each electronic area has a common point, the house
itself has a common ground area (as near as I can do), as do
my towers (each has a ground that everything related to that
tower grounds to), and even my yard entrance has grounds for
incoming cables from the fields where towers or antenna area
(four or five entrance points).

People get into trouble by plugging some things into one
outlet, and other things into another outlet, and then maybe
mixing in a third or fourth connection to other stuff
without common grounding. The same things that cure my RFI
problems correct lightning problems.

73 Tom