LIGHTNING STRIKE SURVEY
1 - Have you ever taken a direct hit to either antennas or towers?
YES, a number of times over the years. (I've seen it!)
2 - If YES, was your damage MAJOR, MINOR, NONE ?
NONE.
3 - How is your tower grounded?
Each of my two aluminum towers has six 4-foot copper ground rods
spaced equally around the base of the tower. The ground rods are tied to
each other via a 12 gauge copper wire "ring". 24 lengths of 12 gauge
wire are soldered to equally-spaced places around this ground "ring",
with their opposite ends tied to the tower at six places using SS hose
clamps at the tower legs and sides.
4 - How are your feedlines and rotor/control cables routed?
My feedlines and rotor cable are routed all the way to the ground and
securely taped to one of the tower legs inside the tower. They exit the
tower at the base and are then routed along the ground (buried only about
2") to the shack. (Beam antennas are at DC ground atop the towers.)
5 - How do you protect/isolate your radios/rotor control boxes/etc. ?
I do nothing out of the ordinary at the shack end. The equipment is
grounded via their power cords to power ground. The equipment is tied
together by their interconnecting cables. The 160m and 80m coaxes which
have their shields connected to the well-grounded tower bases provide the
shack's best DC ground. (All coax shields are tied together at the
shack end by virtue of the coax antenna switch.)
Like Ben Franklin's invention, a well-grounded tower attracts
lightning. Also like the well-grounded lightning rod, the "juice" will
be conducted safely into the ground at the tower base rather than
elsewhere, such as through cables to the shack.
73, Earl, K6SE
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