> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Nick Pair
> Sent: Monday, July 03, 2006 8:35 PM
> To: ersmar@comcast.net; bthorson@4smps.com; towertalk@contesting.com;
> n6ry@arrl.net
> Subject: [TowerTalk] Water tower omni
>
> I vote for the 4 pole folded dipole with the dipoles spaced 90 deg.around
> a mast horizontally and phasing harness distance vertically. The
> commercial type where the dipoles are welded to arm on half opposite feed
> point. They have survived many a strike in commercial installations. You
> would want to use discharge devices above them on support mast and have
> everything well bonded together and to lightning down wire to whatever
> ground is present at tower base. There should be a grid if this is a
> community water system and access to this is important. The individual
> patterns on these are great enough that you get pretty good omni out of a
> set of four. Use factory spacing from support for best omni.
> Also if you can run the feed line horizontally from the support pole
> base through a grounded run of metal conduit just big enough to
> accommodate the coax will choke the large current surge down to a less
> than melt down level. About 20 feet will do it.
> That's my $.02 worth anyway,
>
> Nick WB7PEK
Running coax through metal conduit without grounding it at each end of the
conduit is asking for a large arc between the coax and conduit, not
recommended.
73
Gary K4FMX
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