On 09/08/08 03:08 am Roger Cooke wrote:
> My tower is about 80ft from the house. I have a catenary wire fixed on the
> tower at about 15ft with a D shackle and at the house end with a wall bolt
> fixed right through the wall of the house, a bungalow actually, at about ten
> feet. I then suspend all the cables from that with a series of large cable
> ties fixed at every three feet. At the tower end, the catenary is controlled
> by a winch, enabling me to lower the whole thing for additional cables or
> maintenance etc. I have a loop of cables at the tower end to allow this to
> happen. It all works very well. I have five coax and two control cables in it
> at present.
Note the following from p. 7 of the Polyphaser Technical Document
TD1016.pdf
(http://www.polyphaser.com/NR/rdonlyres/C1565001-F81A-4AC2-A98F-E88B8037F988/182/TD1016.pdf):
"Since all towers have some
inductance, leaving the tower at a point above ground will allow
some of the strike current to continue on the coax line (both the
center conductor and shield) toward your equipment. Once at the
equipment, the current will follow the chassis to the safety ground.
This could elevate the equipment cabinets to deadly voltages,
deadly for both people and components."
Following this advice, I brought everything down to a large electrical
box at the base of the tower, and from there everything runs in buried
metal conduit into the shack.
73
Alan NV8A
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