Pat:
For my shunt-feed system, I use a hybrid of the two techniques (individual
attachment points plus with a wire buss surrounding the tower base). I connect
several radial wires to each #2 ground wire off the tower legs. For this is
use small (1/2 inch) stainless hose clamps plus some aniti-ox goop. I realize
now I actually could have soldered the wires and might still do so.
I connect the coax shield at the series gamma cap box to ground (and to
the radials) via a loop of #2 ground wire that I have laid on top of the
concrete base. The loop runs just inside the tower legs, so it's about three
feet in diameter. I connect a tail on the loop to the tower base (and the
radials and ground wires) with Harger #222T clamps. I also use small PVC T's
on small wooden boards to support the loop and insulate it from the concrete
(probably overkill or paranoia - take your pick.)
BTW: I had originally intended to use this loop as the main connection
point for all my radial wires. The more I thought of it, the more I disliked
the idea of havning multiple #18 wire ends snaking up from the grass around the
tower base on over top of the concrete. IMO, this would have been a source of
much condternation every time I mowed the lawn around the tower and cut one or
more radials by snagging them on the mower. I decided to keep the loop in
place, but to use the three leg ground wires as the attachment points for the
radials.
One thing you should do is run all your coax and control cables INSIDE the
tower to minimize coupling from the live tower steel. This might be an Old
Wives' Tale, but putting the cable inside the short (64 foot) tower was easy
enough for me.
BOTTOM LINE: A copper bisds bar or wire around the tower's concrete base will
work just fine if you make your connection from it to the tower and its ground
system via a low impedance like a hefty ground wire or copper strap.
73 de
Gene Smar AD3F
> I am in the initial stages of planning the shunt feeding of my tower. How
> important is the attachment point/points for the radials. Does it matter if
> they all radiate from one or two attachment points/legs at the base of the
> tower
> or do they need to be spread out on a ground buss? Would it be okay to have
> a
> copper pipe buss around the perimeter of the 5 x 5 cement pad and attach them
> to
> that?
>
> My tower is 8 ft from one end of my house( no the falling ice doesn't worry
> me
> ). Would anything be gained by having a remote attachment point at each
> corner
> of the house so radials can run into the front and back yards?
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather
> Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
> and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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