Fellow TowerTalkers
Where should the coax surge suppressors go? At the base of the tower or at the
shack entry box or both?
I have my tower coax grounded at the tower base. Just put in a new underground
run of hardline to the shack entrance which is about 130 feet from the tower.
I have new metal boxes at the tower and at the shack entrance. So where should
the coax arrestors go? I'm thinking at the shack entrance box since the
hardline inductance would block some of the surge and stretch it out in time,
making the suppressor more effective at the shack entrance. The shack entrance
box is bonded to the tower by a run of #4 solid copper and a number of 8 foot
ground rods along the way. I have additional radial ground runs coming off the
tower with ground rods every 16 ft or so. Unfortunately the house service
entrance is on the opposite side of the house 50 ft away from the shack
entrance, but I plan to run #4 to it as well, which raises the question of
effective bonds. Page 6.11 of Grounding and Bonding for the Radio Amateur
(first addition) says that a bonding run of 40 to 50 ft will have too m
uch inductance for an effective bond (at lightning energy frequencies) but
goes on to say MIL-HDBK-419A shows towers bonded to building grounds up to 200
ft away. Big difference between 5o ft and 200 ft.
tnx
N3AE
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