Lightning Protection

[Chuck W4MIL]

Just a few suggestions on this subject.  I'm an ordinary ham and not an
expert so your individual mileage may vary.

Regarding "how" to set up an HF station and proper grounding may I suggest
returning to the license manuals or study guides and re-reading the part(s)
that address the subject.  Even the older "Now You're Talking" study guide
for Novice and Technician Class license gives the differences between RF and
electrical grounding plus some diagrams on how to connect your rig.

The ARRL handbooks from years gone by have plenty of info on the subject as
does any number of antenna books.  A check with local authorities will give
one the local NEC code interpretations which describe, in detail, primary
ground, additional ground rods, etc......

There are numerous ways to achieve both RF and electrical grounds and often
ones individual circumstances must be understood before any recommendation is
made.

It should be remembered that there is no "foolproof" guaranteed means to
avoid a direct lightning strike.  We live in the lightning capital of the USA
here in Florida and most hams around here can be heard saying, "I'm going to
ground" when T-storms are threatening.  We simply disconnect the rigs from
any coax and some of us disconnect the coax from the antennas where it enters
the house.  Unplug all telco connections and pull the power cords from the
wall sockets.  I disconnect the RF and electrical ground leads outside of the
house.  Lightning can, and will, enter via a ground lead.  I find it best not
to have the lead connected when the T-storms are present.  Otherwise,
everything remains connected and the usual static drains are in place in the
coax to bleed off static charges that are always building on the antennas.

I recently repaired a friends TS930S and found several "traces" on a couple
of PC boards had simply vaporized.  He said there were storms around but he
did not have a direct lightning hit near his house.  There was no damage to
the rig where the antenna was connected either, meaning the damaging current
had entered by some means other than the line cord or antenna.  The rig was
grounded directly to an 8ft rod just outside his window.  He had a phone
patch in the mic circuit and the phone patch was hard wired to the telco
block in his shack.  I popped the lid on the phone patch and sure enough
there were numerous vaporized traces on the PC board.  Apparently a lightning
strike occurred in the vicinity and the induced voltage in the telco lead in
made its way to the patch and through the mic input circuitry before it found
a good ground return.  Once again, a good reason to disconnect all when old
man lightning is playing around.

Well, just a few thoughts that might help.

Best 73

Chuck
W4MIL

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