Ham Op wrote:
"Physical damage is generally caused by direct strikes."

Lightning can produce awsome distruction from its millions of volts and
thousands of amps. Stories about it are informative, amusing, and
abundant.

Damage is mostly avoidable. High towers are nearly certain to be struck
repeatedly in passing thunderstotms. I`ve worked in medium wave
broadcasting, Short wave broadcasting, land-mobile radio, aircraft
radio, and microwave relay systems aplenty. I worked decades with a
worldwide corporation that had towers across the U.S.A. and several
other countries in the world. That corporation had its many towers
fitted with inverted Copperweld ground rods at the top to serve as
lightning rods to take most of the hits the towers received. At their
bottoms, the towers` lightning energy was shunted off to the earth
through ground rods driven into the soil around the towers. It worked.
There was no vaporized coax, tower lighting wires, or anything else.

We had to operate perpetually. We couldn`t pull the switch and throw the
coax out the window, even if someone were on hand to do so.

Evidence of lightnong strikes were the small pits it made in the
lightning rods.

Best regards, Richard Harrison, KB5WZI

I understand the concept, but if I have a wire antena , going to ladder
line, the trasitioning to coax, all outside, with the coax finally
snaking into the house and hooking up to the antenna tuner...

Where would I put grounds, how would I attach them, etc...???

I'm having trouble visualizing doing this grounding without it affecting
the antena performance.

Jerry

(who was generalizing when talking about house damage, but was really
just looking for help with ideas for grounding and thank you all who
have responded)

In article ,
(Richard Harrison) wrote:

Ham Op wrote:
"Physical damage is generally caused by direct strikes."

Lightning can produce awsome distruction from its millions of volts and
thousands of amps. Stories about it are informative, amusing, and
abundant.

Damage is mostly avoidable. High towers are nearly certain to be struck
repeatedly in passing thunderstotms. I`ve worked in medium wave
broadcasting, Short wave broadcasting, land-mobile radio, aircraft
radio, and microwave relay systems aplenty. I worked decades with a
worldwide corporation that had towers across the U.S.A. and several
other countries in the world. That corporation had its many towers
fitted with inverted Copperweld ground rods at the top to serve as
lightning rods to take most of the hits the towers received. At their
bottoms, the towers` lightning energy was shunted off to the earth
through ground rods driven into the soil around the towers. It worked.
There was no vaporized coax, tower lighting wires, or anything else.

We had to operate perpetually. We couldn`t pull the switch and throw the
coax out the window, even if someone were on hand to do so.

Evidence of lightnong strikes were the small pits it made in the
lightning rods.

Best regards, Richard Harrison, KB5WZI

Jerry wrote:
"I`m having trouble visualizing doing this grounding without affecting
antenna performance."

Shortwave radio antennas I`ve used were all made from Copperweld wire to
withstand lightning and weather. Also, copper wire can stretch and
fatigue. Copperweld`s steel core prevents this.

Signal Corps rhombic kits use (3) No.12 Copperweld wires twisted
together to make a cable used for antenna and transmission line. A
special Wihd Turbine Company insulator is included to space the line for
600-ohm impedance. These bolt atop short tower secttons used as
transmission line supports. Unless military surplus is available,
substitutions would be necessary. But, open-wire line is rugged and
withstands the challenges.

Pick a place outside your shack to drive ground rods to serve as a
ground bed for your antenna system to dump your lightning strikes to.
Place the rods at about the length of your ground rods away from each
other. The more rods, the better. Cost will prevent too many rods.

Interconnect all the ground rods and connect this ground system to your
electric service ground system. It`s the law in most jurisdictions.

Run your open-wire line from your antenna to a point above your ground
bed. You need arc-gaps between each transmission line cable and the
earth. Form copper vees to make arc-gaps. The vertex of one Vee is going
to face another to make a pair. Connect one Vee firectly to the earth.
Connect the other of the pair directly to the transmission line cable.
Do the sane for the other transmission line cable.

When the gaps are completed, adjust the space between them until they
flash over from your transmitter power, then back off until they just
don`t flash over. You should now be ready for lightning on the
transmission line. Connect your ladder line, twin lead, coax or whatever
you will use to complete the connection to your radio to your open-wire
line here above your ground bed.

Isolate the radio from the powerline through a brute-force filter with
MOV`s added for lightning suppression.

Audio, control, and any other wires connected to the radio also need
filters with MOV`s added but the current carrying capacity of the
filters can be lower than that required for the power wires in most
cases. A common ground point is required for all these filters.

If you don`t use coax somewhere between your radio and antenna, you will
lose some of the protection it provides. Its close internal spacing
couples its conductors tightly. We found even solid-state receiver
front-ends weren`t endangered by lightning because of grounded antennas
and the coax. It would flash over before it let lightning through.

Best regards, Richard Harrison, KB5WZI