While I highly respect Bob's opinion and have learned a lot from him about
home-brewing baluns, I feel his recommendation is the second choice I would
make (when starting from scratch).
If you already have an asymmetrical tuner (a.k.a. T-Match), then indeed do
exactly as Bob recommends. There's no better way.
If you are starting from scratch and haven't bought a tuner yet, then I
would personally prefer to buy a true symmetrical tuner and not use any
balun at all. Luckily these symmetrical tuners are available from a
multitude of sources these days.
If you need a balun for your existing unsymmetrical tuner, Bob's "Monster
Balun" (as I call it) is probably the very best thing you can possibly do.
My 2 cents worth.
Now, for 80 thru 10 meters:
What works good: 2x 13m dipole.
What works better: 2x 17m dipole.
What works best: 2x 20m (a full size 80m dipole)
What also works: 2x 10m (though still good, will be OK, but noticeably
weaker than all of the above on 80m but do just fine on all other bands).
For 160m, you need a minimum of 2x 30m to get a good signal out.
This still works great for 80 and 40 but for higher frequencies you begin to
get strange lobes, so do as Wes recommends and model it to be sure you get
what you need. Better yet, place a jumper in each leg, or use a second
radiator, or both.
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Robert & Linda McGraw K4TAX
Sent: Saturday, July 09, 2005 2:56 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] was - "Radiates like Crazy"???? No
One doesn't need a lot of space or high supports for a wire antenna. In
fact if one desires to use a wire, make it as long as you have space and
supports. Feed it in the center with a balanced feed line to a 1:1 balun
and then to any of the multitude of tuners available. With this arrangement
actual antenna length is relatively un-important. Granted, a resonant or
near resonant antenna will work a bit better. In my case it's a 256 ft
center fed wire at 50 ft.
I know one respondent on this thread said use a 4:1 balun. While that works
in most situations, realize that the step-down is a divide by 4 condition.
Should the load present a Z that is in the order of 25 ohms which is then
divided by 4 or 6.25 ohms, I would question if the tuner has very good
efficiency at the required operating Z. I doubt it. Most will only go to
12 to 15 ohms on the low end.
On baluns, the basic coax coil flat wound on a piece of PVC pipe makes one
of the most efficient, high power handling baluns available. Cost is for
the coax, I suggest some 15 to 18 ft of the RG-213 type, and some 3" OD PVC.
73
Bob, K4TAX
----- Original Message -----
From: "Curt" <k3ey@yahoo.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, July 09, 2005 1:02 PM
Subject: Re: [TenTec] was - "Radiates like Crazy"???? No
While all you guys are patting yourselves on the back
on how well these antennas work don't forget about the
poor souls, myself included who don't have space for a
135 foot dipole as well as other restrictions real
people live with.
Been there done that and YES they work, and work well,
IF you have space which most hams living around and in
cities do NOT have. All you are doing is inviting
trouble using ladder line otherwise. Preaching with
zealous shouts of how well they work boarders on
psychotic. They should rename these antennas
"Nightmare Generators" for the masses who don't have
farms and that live where most of the human race
lives, among others of the same species.
For the newbies reading this thread. It's like the
good book, you get out of it only what you believe and
even that is arbitrary because of the bias slant that
was indoctrinated into your mind while it was still
malleable.
Try it yourself, if it works, great, if not do what
most normal hams do, use coax.
k3ey
--- Carl Moreschi <n4py@arrl.net> wrote:
> I also agree. A 135 foot dipoe as high as possible
> (50 feet or more in the
> center, inverted Vee is fine) fed with open wire or
> ladder line works very
> well on 80 to 10 meters. I also suggest using an
> outdoor tuner such as the
> LDG RT-11 mounted right under the antenna on the
> ground. You then run coax
> from the tuner into the house. This is a great
> multi-band setup. I have
> used these many times and I'm always impressed with
> them.
>
> Carl Moreschi N4PY
> Franklinton, NC
> ----- Original Message -----
> From: "M. P. Haynes" <k4beh@juno.com>
> To: <tentec@contesting.com>
> Sent: Saturday, July 09, 2005 11:53 AM
> Subject: Re: [TenTec] was - "Radiates like
> Crazy"???? No
>
>
> > Hi Jack,
> >
> > Welcome to the club! My suggestion from many
> years of experience is to
> > put up a 135 foot dipole as high as possible.
> Feed it with ladderline
> > and a tuner with a 4:1 balun. It will work all
> bands and give you great
> > results. You can buy it prepackaged for about $40
> It is made by a
> > company called Van Gordon and is sold by most
> radio distributors (Amateur
> > Electronic Supply, Ham Radio Outlet,etc.) If you
> have room for more
> > antennas later you can make or purchase more
> elaborate and complex ones
> > that will work with additional gain and
> directivity in a specific
> > direction (beams, quads, etc.) but as a first
> antenna you'll find the
> > dipole hard to beat! Pick up an antenna handbook
> at a hamfest somewhere
> > and it will give you lots of ideas and insight
> into antennas.
> >
> > 73,
> > Pat Haynes-K4BEH
> > Hamming since 1954
> >
> >
> > On Sat, 9 Jul 2005 09:42:01 -0500 "Jack Rubin"
> <jack.rubin@ameritech.net>
> > writes:
> > > Excuse me for jumping in here, and really, I'm
> not trying to pour
> > > gasoline
> > > on the fire!
> > >
> > > I'm a new Tech with an Omni D waiting for me to
> pass my code test;
> > > in the
> > > meantime I'm reading this list and a few others
> and soaking up a lot
> > > of
> > > information (including the fact that various
> folks have had varying
> > > experiences and often have divergent opinions).
> > >
> > > I'm especially interested in this thread because
> I've yet to install
> > > a
> > > "serious" antenna - I've been SWL'ing with a
> slinky - and I'm
> > > looking for an
> > > antenna with the magic combination of low cost,
> low visual/spousal
> > > impact
> > > and good performance. At this point, something
> like the folded
> > > dipole might
> > > make some sense for space reasons, but here's my
> specific question -
> > > has
> > > anyone had experience with the Isotron line of
> antennas? They are
> > > at
> > > http://www.isotronantennas.com/ - not an
> all-band product but
> > > definitely
> > > "stealthy".
> > >
> > > Thanks and 73s,
> > >
> > > Jack
> > > KC9HVE
> > >
> > > _______________________________________________
> > > TenTec mailing list
> > > TenTec@contesting.com
> > >
> http://lists.contesting.com/mailman/listinfo/tentec
> > >
> > >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> >
> http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
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