[TowerTalk] Does a Shunt Fed tower Care...?

[ersmar@comcast.net]

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?
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