Cushcraft has the 6270 triband yagi, but unfortunately the 2m and 70cm elements
are vertical! It is the right polarization for 6m, though.
73s John AA5JG
--- On Fri, 3/5/10, Eugene Zimmerman <ezimmerm@erols.com> wrote:
> From: Eugene Zimmerman <ezimmerm@erols.com>
> Subject: Re: [VHFcontesting] Getting beginners interested in VHF Contesting
> To: "'David Pruett'" <k8cc@comcast.net>
> Cc: "'VHF Contesting Reflector'" <vhfcontesting@contesting.com>
> Date: Friday, March 5, 2010, 3:11 PM
> Dave
>
> No doubt a VHF tribander would be a great boon to VHF
> activity. As far as I
> know only one was ever marketed. Ariane, the company that
> took over C3I when
> Owen Wormser retired, had one on their books. It was about
> 15 feet long but
> was not cheap - in the $300 range or maybe more - I don't
> remember. I know
> who designed this one and his antennas work so I assume
> this one would have
> worked. Unfortunately Ariane succumbed to high aluminum
> prices soon
> afterward so we have no way of knowing.
>
> Costs are not trivial because I'd guess it took some real
> engineering to
> make all three section work independently and aluminum
> costs are
> unpleasantly high.
>
> The first homebrew HF tribander I ever saw was designed by
> my mentor, Len
> Chertok W3GRF, and had 2 el on 20 3 el on 14 and 5 el on 10
> in line. It was
> around a 36 foot boom and was designed empircally there
> being no modeling
> software available in the 1950's accesible by hams. It gave
> a very good
> account of itself and I suspect that a VHF in-line
> tribander might work with
> very little interaction between the bands. For the
> experimenters I would
> start with WA5VJB 6 el cheap yagi on 2 and an 11 el cheap
> yagi on 432. That
> makes a ~135 inch boom so far. At the rear end I would add
> a 2 el 6M moxxon
> either homebrew or the one from Par Electronics if Dale
> still sells those.
> Even buying the 6M portion I'd bet the antenna would cost
> less than $150.
>
> If someone designs a tribander, models it and can describe
> it in 2 QST pages
> I will offer to publish it in the World Above 50 MHz. The
> key of course is
> something that is readily reproducible without tons of test
> equipment. That
> is the primary virtue of the Cheap single band Yagis.
>
> 73 Gene W3ZZ
>
> -----Original Message-----
> From: David Pruett [mailto:k8cc@comcast.net]
>
> Sent: Thursday, March 04, 2010 8:43 PM
> Cc: VHF Contesting Reflector
> Subject: Re: [VHFcontesting] Getting beginners interested
> in VHF Contesting
>
> From the conversations I've had with non-VHFers, cost is a
> major issue to
> getting on VHF/UHF. On HF you can toss a $5 dipole in
> a tree, feed it witn
> junk coax and work a bunch of people on 80 and 40. As
> W3ZZ points out, that
> doesn't work on VHF. Most decent VHF/UHF antennas are
> at least $100, and a
> decent low lost feedline is at least $50, depending on how
> much length you
> need. So $150 gets you ONE BAND worth of effective
> antenna. Joe706 needs
> $450 worth of antennas (assuming he has a support for them)
> just to try
> something he might not even enjoy doing. And if he
> want to get on a band
> where he needs a transverter, that's another $400.
>
> W3ZZ and I were discussing this at Dayton last year.
> I compared this
> situation to the 50's, when Mosley or whomever
> commercialized the first
> 20-15-10 triband beam. Three bands from a single
> aerial and feedline,
> reasonable cost and manageable size did a lot for activity
> on those bands.
> Where would we be today in regards to contesting and DXing,
> without the
> triband beam?
>
> What we need is somebody to come up with a good 50-144-432
> triband antenna
> with a single feedline to go along with the IC-706s and the
> various Yaesu
> FT-8x7s out there. If it were commercially available
> in the range of
> $100-$200, that would be terrific. Icom and Yaesu
> have done a terrific job
> with creating 50/144/432 rigs at reasonable cost, now if
> somebody could
> solve the antenna issue as well...
>
> Lacking such an antenna, I think WA5VJB's "Cheap Yagis" are
> a great way to
> get started for low $$$. I'm gonna try to build a few
> this summer for two
> reasons: 1) To see for myself how reproduceable these
> antennas are, and 2)
> to have some antennas I can loan out if any of my "Joe706"
>
> friends wanna try VHF contesting.
>
> Just my $0.02
>
> 73, Dave/K8CC
>
>
> James Duffey wrote:
> > Hey Eric - Nice to hear from you on this topic. I was
> not advocating that
> everybody operate with all homebrew equipment.
> >
> > Nothing wrong with commercial antennas, in fact I have
> a Cushcraft 13B2
> that I rove with on occasion. It was given to me. I just
> like to build my
> own antennas, and show other people how to build their
> own. Up to 432 MHz
> at least, there are several good beam designs that work
> well as built with
> no testing or tuning required, nor special tools or
> instruments, just
> careful measurements. Sure you can tweak a bit more out of
> them with a bit
> of test gear, or build antennas with slightly higher gain
> with some testing
> and tuning, but for the beginner, better is enemy of good
> enough. The simple
> designs should be enough to get them on the air quickly,
> cheaply and get
> them hooked.
> >
> > I have given several talks on VHF contesting and
> roving over the past year
> and a half. I always take a few antennas to show and people
> are always
> amazed that simple homebrew antennas like the WA5VJB
> designs are available
> and work well. I always get comments when I show the WA5VJB
> antennas like,
> is that all there is to it? And hey, I can build that. My
> favorite: Does
> that work as well as an Arrow? The guy with the
> 706/7000/FT100 or whatever
> usually uses it on 2M and 70cm FM and that is it. If we can
> get those guys
> on the weak signal modes, which the simple homebrew
> antennas they can do
> without much investment, then we can hook some new blood
> into contesting.
> Even getting the 706 guys who use loops to switch to beams
> would help a lot.
> But getting guys on loops from verticals is a big step, if
> they do it for a
> contest.
> >
> > At 6M, the N2MH version of the Moxon is easy to build
> from common
> materials and is a great performer compared to the loop or
> dipole that the
> guy may have been using. Again just careful lmeasurements
> are required and
> pretty much all the parts can be purchased locally.
> >
> > I like the notion of distance scoring used in at least
> one contest and I
> think that if a guy uses computer logging, like Roverlog,
> the distances are
> calculated and scores calculated with no additional input
> from the user, so
> it really isn't any more complicated. The Spring Sprints
> will use distance
> scoring so we can all see what that is like.
> >
> > For those on the list that hadn't noticed yet, Eric
> has one of the
> > greatest calls for VHF contesting there is. He is also
> one of the
> > premier rovers in the Rocky Mountain Division and does
> a bang up job
> > on 10 bands from that many or more grids, even in
> January. - Duffey
> > _______________________________________________
> > VHFcontesting mailing list
> > VHFcontesting@contesting.com
> > http://lists.contesting.com/mailman/listinfo/vhfcontesting
> >
> >
>
>
>
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