I concur with Dave if the stone wall is close to the feedpoint -- go
through or just under the wall with the radials. It avoids the wire zigging
over the wall, and the possible current issues therein (a point raised
earlier).
If the wall is a ways out, don't bother. Simply terminate the radials at
the wall.
Non-empirical and entirely subjective tests here have shown me that radial
length isn't nearly as important as density and symmetry immediately around
the feedpoint.
Mike N1TA
On Mon, May 14, 2018, 12:32 PM Dave Sublette <k4to.dave@gmail.com> wrote:
> Has anyone suggested to just tunnel under the wall? I don't know the
> construction of that particular wall, but stone fences in Kentucky are just
> dry stone stacked. A sharp stick would poke a hole under it and then you
> could just pull the radial under and take it where you wanted to go. BTW
> -- stone fences in KY are usually registered historical things and one must
> be careful doing thing to or with them. But on a dark night, who would
> notice ?? ;-)
>
> 73,
>
> Dave, K4TO
>
> On Mon, May 14, 2018 at 12:20 PM, Jim Thomson <jim.thom@telus.net> wrote:
>
> > Date: Mon, 14 May 2018 10:00:10 -0500
> > From: Kelly Taylor <ve4xt@mymts.net>
> > To: Les Kalmus <w2lk@bk-lk.com>
> > Cc: towertalk@contesting.com
> > Subject: Re: [TowerTalk] Laying out radials around a stone fence
> >
> >
> > Sent from my iPhone
> >
> > > On May 14, 2018, at 08:50, Les Kalmus <w2lk@bk-lk.com> wrote:
> > >
> > > Radials on/in the ground aren't resonant. Most of the current in them
> > will be close to the tower regardless of the length of those radials so
> put
> > down as many as you can at whatever length they come out which will be
> > better than no radials.
> > >
> > > Les W2LK
> > >
> >
> > >Yes, however the engineering on radials has progressed past asking
> > whether on- or in-ground radials are resonant and now considers the
> > benefits of reducing resisitivity of the soil, as Jim Lux so aptly
> > described. It?s not just about being part of a return path.
> >
> > >The axiom about more short radials being better than fewer long radials
> > remains, especially if your space or wire supply is limited. But if you
> > have more of each, radials farther out are still beneficial.
> >
> > >It?s probably still wise to not sacrifice a dense field of radials near
> > the antenna at the altar of fewer longer radials, but it didn?t seem
> space
> > or wire was limited, merely that there?s an obstacle in the way.
> >
> > >73, kelly, ve4xt
> >
> >
> > ## AM broadcast stations around here all use 120 radials..and all are
> at
> > least .4 wave long. Thats a min of four tenths of a wavelength. At
> .4
> > wave long, the distance between the far ends of any
> > 2 adjacent radials is optimized. In ON4UNs low band book, he depicts
> > the bulk of the ground reflection occuring .25 wave lengths out from
> the
> > base of the vertical. If thats the case, then I can see
> > why you would want them a little longer. If I had a rock wall in the
> > way, I think I would be inclined to go over top of it...or stop at the
> > wall, then continue on the other side. But that would all depend
> > on how close the wall was to the base of the vertical.
> >
> > Jim VE7RF
> > _______________________________________________
> >
> >
> >
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> >
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