David,
Have you tried this one: home.ict.nl/~arivoors/ An Open source 4NEC2 NEC
based antenna modeler and optimizer
73, Lynn wb6dww
>>> Guy Olinger K2AV <olinger@bellsouth.net> 1/26/2012 3:02 PM >>>
Try a postal service mail to K6STI's qrz.com qth. You may be able to
purchase a copy of YO (yagi optimizer) from him. There have been rumors
from time to time that he will respond mail only. 73, Guy. If you DO get
a response from him, let us know here.
73, Guy.
On Thu, Jan 26, 2012 at 3:06 PM, David Gould <dave@g3ueg.co.uk> wrote:
> Dan, Bill, Guy
>
> Thanks for your input...
>
> It looks like the project may be too big in time and cost if NEC4
> license is required. I will have to think further before committing.
>
> Thanks again.
>
> 73,
> Dave, G3UEG
>
>
>
>
>
>
>
>
> At 00:01 26/01/2012, dan edwards wrote:
> >to me, anyway, the OWA 'burns' a director for broad-band impedance
> >matching..so, a
> > '4 el OWA' is really a 3 element yagi...don't think the first
> > director contributes much to
> > forward gain or f/b.....K3LR & W3LPL have 40m monsters built that
> > way....making a
> > broad band yagi with gain very similar to a 3 el one...except with
> > a better match across
> > a wider freq. span...
> >
> >
> >my $0.02 worth...73, w5xz, dan
> >
> >
> >--- On Wed, 1/25/12, David Gould <dave@g3ueg.co.uk> wrote:
> >
> >From: David Gould <dave@g3ueg.co.uk>
> >Subject: Re: [Antennaware] 3-element HF yagi design
> >To: "Guy Olinger K2AV" <olinger@bellsouth.net>
> >Cc: antennaware@contesting.com
> >Date: Wednesday, January 25, 2012, 8:50 PM
> >
> >Guy,
> >
> >Thanks for the information. (I meant NEC-2 not NEC-3, and Yes, I
> >appreciate EZNEC is not an optimiser.)
> >
> >Ok there would be some technical issues to resolve, but the main
> >question still remains - whether there are any **fundamental
> >reasons** why it is NOT be possible to design a 3-element yagi with
> >a frequency independent feed? I have read a bit about OWA yagis, but
> >I have only found reference to ones with 4 or more elements.
> >
> >73,
> >Dave, G3UEG
> >
> >
> >
> >
> >
> >
> >At 20:03 25/01/2012, Guy Olinger K2AV wrote:
> > >EZNEC is not an optimizing modeler. So design iterations with the
> > >model are manually directed.
> > >
> > >HF yagis from a standing start are best done with YO. Which, alas,
> > >is not being marketed by Brian K6STI any more (unless someone knows
> > >something new ??). Try USPS mail to Brian's QRZ.com address. I
> > >will not expound the long story about how things got to be this way.
> > >
> > >EZNEC (with NEC2 engine) has a limited stepped diameter correction
> > >mechanism, which is not part of the NEC2 process. Its limitations
> > >would seem to fit an HF yagi.
> > >
> > >NEC3 was superseded by NEC4, which is licensed from Lawrence
> > >Livermore Labs. See the wikipedia article. Only NEC2 and NEC4 are
> > >available as processing cores.
> > >
> > >73, Guy.
> > >
> > >On Wed, Jan 25, 2012 at 12:55 PM, David Gould
> > ><<mailto:dave@g3ueg.co.uk>dave@g3ueg.co.uk> wrote:
> > >I would be interested in whether it is possible to design a 3-element
> > >HF yagi (with tapered aluminium tubing) that has a frequency
> > >independent feed. I am willing to compromise top-notch performance
> > >for flexibility/simplicity. My thinking is to feed with a standard
> > >ratio Balun (eg 50ohm or perhaps 25ohm)
> > >
> > >Does anyone already have a model for any of the HF bands (but 20m
> > >would be preferred if available) that they would be willing to share?
> > >
> > >I don't know whether I am asking for the impossible here!!
> > >
> > >Second question.. Can I model such an antenna reliably with EZNEC+ 5
> > >using the NEC 3 engine? (I have been advised that NEC3 is not good
> > >enough and NEC4 is really needed.)
> > >
> > >73,
> > >Dave, G3UEG
> > >
> > >
> > >_______________________________________________
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> > ><mailto:Antennaware@contesting.com>Antennaware@contesting.com
> > >http://lists.contesting.com/mailman/listinfo/antennaware
> > >
> >
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