I Ground my MA-550 tower by using a wide braided strap to connect the
rotating tower to the 3 8-foot long ground rods that surround the concrete
base (the 3 ground rod pic is shown in the ARRL Antenna book and maybe the
ARRL Handbook too). The MA-550's self-supporting fixture is also well
grounded to each of these 3 rods.
I disconnect from the radio and ground all coax cables and rotor cables when
not in use. My MA-550 tower is down (nested) except when I am on the air
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