I would suspect a poor grounding system on the tower. If the ground is a
rod driven into the Earth, then the impedance needs to be as low as
possible. Once the ground system takes a surge, glass
(( (crystalls?)))
will formin the dirt on and around the rod. The impedance then climbs
and the numberof strikes to the tower increase. The amount of
impedance in your groundnetwork determines the amount of static charge
that can build on the towerand how fast the charge can bleed.

(((The tower sites are only about 100 feet apart, ground substance is
the same, clay/rocks, 1st foot then clay…… The first tower ground, is
a 4 ft hole, with ¾" rebar then driven deeper,1.5ft, w/ horz bars 1ft
on center from bottom of hole to top, where a ¾ steel plate was welded
to vertical bars, and to the plate, strong hinge plate connected to 25
rohn tower. The 'other site', is two 4" pipe, 5ft, in the ground, and
welded to fence. Fence is 2"2/8 upset tubing that goes around
property/everything welded. ((fence is 5 foot tall) and as stated part
of the 'gournding system',,,? The first 'site' was not connected to
the primenter fence,,problem???)) If you are familur with the ''bird
tilting over and drinking from the cup", you can picture in your minds
eye, my 'tilting tower'. It is about 75ft tall, with a uhf/vhf duel
band at top of mast, four ft. below that is a two meter horz omni
ground plane.)))

Can you describe how each tower was configured at the top and how it
was grounded? What is important to know if the top ended up with sharp
point (mast, VHF vertical antenna, etc.) or Yagi type antenna, like
tribander etc. without anything pointy protruding above.
Yuri, K3BU

((( Both towers carried almost the same 'items', vhf/uhf , and 4 ft
below that, clover leaf horz ground plane.)))


but their tower lighting chokes kept
lightning off the a-c power source.

((( What do you call these chokes, I know I have read about, but at
the moment I am blank.)))


The broadcaster starts his lightning protection at the tower top with
a small lightning rod extending above and beyond the beacon to take
the hit and avoid expensive repairs at the tower top.


((( Is this something like the antennas I have seen that have a
'center core' copper rod???)))

Tower guy insulators are doubled and tripled where they connect to the
tower so that static breakdown occurs to the earth instead of at the
tower.


((( Where do I 'see/read' about this??)))


One such line was on a small single story U-Stor-It building between
two very tall radio station towers, that was assumed to be lightning
proof due to it's location. It was hit and hit hard when neither
tower was hit

……"How did your team "know" what was struck?

"""…my question was and is,,,, why?




(((((((((((((((((((This statement is the one that makes the
most sense to me)))))))))))))))

Lightning is Female. 20 million volts & 100 thousand Amps will do as
it damm
well pleases!

((((Last, but not least,,,,,,, thank you, WILL implement input,
cl&73))))