There have been some good suggestions as to grounding. A good Single Point
Ground (SPG) is essential.
As to supressors, they can/may *help* when properly grounded and the rest of
the house is properly grounded.
Supressors on the phone, cable, and electrical lines coming in also help,
but are not guarantee. There's a lot of wire in a house and a strike a mile
away can induce as much as a 1000V per meter of wire. Even with grounding
you can not prevent strikes from causing the voltages to rise in the house,
but hopefully you can get them to all rise the same so the system sees no
large differences in potential.
I would add that where lightning is concerned, nothing is absolute and each
strike is has its own characteristics and the strength varies over many
magnitudes from weak to the so called super strikes. Fortunately the super
strikes, which are now believed to have brought down a couple of airliners,
are rare.
I've said this many times here on the group, but the tower shown in
http://www.rogerhalstead.com/ham_files/Tower26.htm has been up for 7 seasons
now and has taken an average of 3 "visually verified" hits a year. ( 5 last
year and none so far this year) If it makes it through the rest of the
season this will be the first year it hasn't taken a hit. The ground system
consists of 32 or 33, 8' ground rods CadWelded (TM) to over 600 feet of
bare #2. The coax and control cables come in through underground conduit to
a grounded bulkhead/SPG at the entrance.
http://www.rogerhalstead.com/ham_files/cablebox.htm Not all cables are
shown in this series. Since the ground system was completed I've had no
damage except for some severely etched coax connectors on the remote antenna
switch near the top of the tower. The switch is opposite the UHF TV antenna
pointing to the left (NW). The South pointing UHF TV antenna and the AV640
(on the shop) are more visible in
http://www.rogerhalstead.com/ham_files/Tower30.htm . The big white C-Band
satellite dish has also been removed in the second photo.
73
Roger (K8RI)
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