----- Original Message -----
From: "j.a.hermans" <j.a.hermans@skynet.be>
To: <TOWERTALK@contesting.com>; <n4kg@juno.com>
Sent: Sunday, September 29, 2002 2:57 PM
Subject: Re: Re: [TowerTalk] Compromise Vertical antenna ground system?
> Hello all,
>
> What about using old coax to realize radials ? And let the velocity factor
> shorten the radials.......... Maybe some cablemakers could produce cables
> with velocity factors worst then the 0.68 ........... Dont know if going
> down to 0.50 and less would be physicaly possible.
> Heard about this somewhere a couple of years ago, but my remeberer has a
> very low velocity factor ( 68 year young ). What can be proved by the
> mathematic prof's ?.......
>
> 73's Jos on4kj
> ----- Original Message -----
> From: <n4kg@juno.com>
> To: <TOWERTALK@contesting.com>
> Sent: Sunday, September 29, 2002 3:32 AM
> Subject: Fw: Re: [TowerTalk] Compromise Vertical antenna ground system?
>
>
> > Here is what W8JI had to say on the subject 2 years ago.
> >
> > Tom N4KG
> >
> > --------- Forwarded message ----------
> > From: "Tom Rauch" <w8ji@contesting.com>
> > To: towertalk@contesting.com, "Avila, Edward" <EAvila@caiso.com>
To: <towertalk@contesting.com>
> > Date: Mon, 21 Aug 2000 20:48:49 -0400
> > Subject: Re: [TowerTalk] Compromise Vertical antenna ground system?
> >
> >
> > > Well, my problem/question: I have very little room to run horizontal
> > > radials from the base of a Butternut HF2V I'm thinking of installing
on
> > > the ground.....at the most 10-15' in some directions, which is a
little
> > > shy of 1/4 for 80 meters! Any suggestions for a compromises ground
> > system
> > > that will make the best of what I have to work with? Would more ground
> > > rods help? More radials, even though they will be electrically short?
> >
> > There are always points of limited return in any design. Radials are
> > no exception.
> >
> > The optimum number of radials for any radial length occurs when
> > the open end of the radials is .025 to .05 wl apart. You should do
> > this on the highest band you are seriously interested in.
> >
> > The point of diminishing returns for radial length is when the radials
> > are about .2 wl long on the lowest band you are interested in.
> >
> > So if you are interested in 40 and 80 meters, the open ends of the
> > radials should be no more than 3- 1/2 feet apart and the radials
> > need be no longer than about 55 feet long.
> >
> > Wrapping a radial around to add length generally does nothing
> > worthwhile.
> >
> > So in the short directions you need fewer radials than in the long
> > direction.
> >
> > What I do is make a measuring line between two stakes. I then
> > "leap frog" the stakes around the perimeter as I pull radials from
> > the center point to each stake.
> >
> > A ground screen will generally only help when you have less than
> > 30 or so radials. With more than 30 or so radials, a ground screen
> > is a waste of time.
> >
> > A ground mounted vertical with a fair radial system is almost
> > always much better than a "no ground" vertical...especially on 80
> > and 40 meters.
> >
> >
> > 73, Tom W8JI
> > w8ji@contesting.com
> >
> >
> >
> > ________________________________________________________________
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>
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