Someone probably has made this kind of measurement, but, it was probably for
ground wave and for 1MHz (i.e. AM Broadcast) and the measurement was made at
ground level.
There has been a fair amount of work (published in obscure places,
typically.. technical reports, conference proceedings of specialist
organizations, etc.) where people have measured patterns, at HF, for mobile
(cars, planes, boats, subs, ships) for skywaves. However, by and large, the
literature I've seen hasn't addressed ground planes. For ground, fixed
installations, the published work is mostly for SW broadcast, where they use
things like steerable curtain arrays (no ground plane involved), or for NVIS
tactical (where, by definition, nobody is putting out 120 radials. etc)
It would be quite time consuming to do the testing, and, if you were paying
by the hour/day/week for the test capability (3d field strength
measurements), you'd quickly realize it's cheaper to just pay to put in the
radials than to test to see if they work.
However, you bring up an excellent point. There's a lot of theory bandied
about, but very little real, objective, calibrated test data. I am working
on developing a suitable amateur oriented test capability for this kind of
thing, but it's been slow going (for a lot of reasons, lack of time being
but one). For a general idea on what's possible, search for "RELEDOP" on the
web.
----- Original Message -----
From: "Tom Champlin" <w0hh@msn.com>
To: "Towertalk" <towertalk@contesting.com>
Sent: Wednesday, December 17, 2003 9:04 PM
Subject: Re: [TowerTalk] Re: One more ground radial question
> That is exactly what I would like to know. I know from experience that
many
> radials will make a vertical work much better, but I would like to see
some
> real world tests, not mathematical conjecture. Surely someone in the
history
> of radio has taken a vertical and added a few radials and taken some kind
of
> measurements and then added more radials ant taken the measurements again,
> and so on. If anyone has a reference to such testing, I for one would like
> to read it too.
>
>
> 73, Tom W0HH
>
>
> ----- Original Message -----
> From: "Jan Erik Holm" <sm2ekm@telia.com>
> To: <towertalk@contesting.com>
> Sent: Wednesday, December 17, 2003 10:37 PM
> Subject: [TowerTalk] Re: One more ground radial question
>
>
> > Is something like this ever confirmed by field
> > strenght measurements?
> >
> > 73 Jim SM2EKM
> > --------------------------------------------------
> >
> > Don Havlicek wrote:
> > > Yes!
> > > In my case ... 60 radials spaced 6 degrees apart .. then
concentrations
> > > of ten radials at 1 degree each for Europe, Japan, South America, and
> > > VK/ZL ... works like gangbusters .. all I need now is to clean out the
> > > shack and put a new feedline out to the vertical again!
> > > Don
> > > N8DE
> > >
> > > va3pl@cuic.ca wrote:
> > >
> > >> ----- Original Message ----- From: "Don Havlicek" <n8de@thepoint.net>
> > >> To: <kb9cry@comcast.net>
> > >> Cc: <TowerTalk@contesting.com>
> > >> Sent: Wednesday, December 17, 2003 12:12 PM
> > >> Subject: Re: [TowerTalk] One more ground radial question
> > >>
> > >>
> > >>
> > >>> I believe the word "optimum" should be replaced with "sufficient".
> > >>> My experience with verticals tells me that 100 radials works much
> > >>> better than 60, especially when concentrated in certain directions.
> > >>
> > ,
> >
> >
> > _______________________________________________
> >
> > 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.
>
> _______________________________________________
> 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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