I use an 80 m dipole (doublet fed with ladder line from shack tuner).
Gets out fine from 160-10m. I use Heathkit SA2060A tuner whhich has
balanced output. The length of the ladder line can be important if you
have trouble with SWR, so may need to add or subtract a few feet until
all bands seem ok. There are recommendations out there on which
lengths to avoid. Give it a try. In theory, the higher freq bands may
have more nulls in the pattern, but I haven't really noticed
difficulties in practice. You will also find a lot of vehement
discussion on whether a 1:1 or 4:1 balun is best. If I were starting
all over again, I might try a folded dipole since the feedpoint
impedance is close to 300 which better matches ladder line, rather
than the 73 of a regular dipole. But no experience with it. Also,
separating the conductor like open wire reduces loss and raises line
impedance, but can pick up more noise and radiate from transmission
line because cancellation is not perfect, compared to closely spaced
conductors. There is a site called
https://www.trueladderline.com/dipoles-all-w7fg-design/ which has
interesting stuff and perhaps sturdiest dipole/transmission line
configuration, as all one continuous wire with no splices or joints.
GL.
Barry WA2VIU
--
Barry Jacobson
WA2VIU
bdj@alum.mit.edu
@bdj_phd
On Thu, Sep 19, 2024 at 2:18 PM Zack Widup <w9sz.zack@gmail.com> wrote:
>
> The photographer Fred Picker was asked a lot of questions where the people
> should have just tried it first. He had a big red stamp that just said "TRY
> IT!" He would just stamp their letter with the stamp, sign it "Sincerely,
> Fred Picker" and send it back to them.
> :-)
>
> Zack W9SZ
>
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
> Virus-free.www.avg.com
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>
> On Thu, Sep 19, 2024 at 10:55 AM Mike Fatchett W0MU <w0mu@w0mu.com> wrote:
>
> > You won't know till you try something.
> >
> > On 9/19/2024 2:40 AM, VE7MHI John D Erskine via CQ-Contest wrote:
> > > On 2024.08.29 07:42, Joe wrote:
> > >> I have gotten from many people comments saying to avoid any of the
> > >> OCF Dipole designs, because of Noise. Especially the probable higher
> > >> level of noise because the place is an "EOC". (Lots of Computers)
> > >>
> > >> They say a OCFD is much more susceptible to letting these noises in.
> > >>
> > >> Yes? NO?
> > >>
> > >> At my home, Noise I have no background in on it being a problem.
> > >> It is sooo quiet here that even on a full sized 40 meter elevated
> > >> vertical,
> > >> I can have the second level pre amp on, and in an empty spot on any
> > >> band,
> > >> the S meter sits at S-0 or maybe tickling up to a max of S-1
> > >>
> > >> Joe WB9SBD
> > >
> > > I dunno Joe. I used a Garant Enterprises GD-8 Windom antenna for about
> > > six years, when I had the space. (~137')
> > >
> > > I was able to listen well down into Lowfer territory, looking for
> > > navigation beacons and such. Was in NW Ontario, and worked coast to
> > > coast on 80 m during the PowWow Club. Worked Resolute Bay, CI8C during
> > > the Transpolar Ski Trek.
> > >
> > > For what you're asking though, I haven't seen any mention of
> > > territory/roof space available to you.
> > >
> > > Recently, and portable, I've been putting up a doublet. Mine is
> > > nominally for 40 m and up, however if you've space you might size it
> > > for 80 m. (Mine is relatively low, wire measured as for a 40 m dipole,
> > > fed with ladder line, and for the moment a Kenwood AT-230 AMU.)
> > >
> > > Other choices might be a large folded dipole, and not last by any
> > > means, a large horizontal loop around the perimeter of the roof line.
> > >
> > > All the best deciding, however I'd just try a few different things
> > > before settling on something. I remind our newer folks, "It's not
> > > likely to be your last antenna/rig/____."
> > >
> > > 73, John
> >
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> > CQ-Contest@contesting.com
> > http://lists.contesting.com/mailman/listinfo/cq-contest
> >
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