GM Doc,
You threw me a curve ball with that "Inverted WYE". Had to look it up.
I think it could be better called an simply "Inverted Y". One up, two
diagonally down.
This is very similar to the old Triple Leg we used for years and years in
the US Army, except we had 3 legs sloping down. Each were made of jeep
whips, but of course you can use wire.
You can resonate all the wires but in your space, you would only be able to
do 20m or above. A 40m version would have to long of legs.
You need to tell us which bands you want to work and how much power you plan
to run.
One of my favorites (since I'm an openwire fan) is the short, openwire fed
Triple Leg.
This is described in great detail on Martin's (DK7ZB) web site:
http://www.qsl.net/dk7zb/Vertikal/tripleleg.htm
Lots of German hams use this antenna on their vacation expeditions.
It will basically work all bands from 40m and up, but you need a matchbox on
all bands.
Martin used an auto-tuner to match his.
This antenna has 1 vertical radiator 7m (23') long - length not too
critical, and then 3 slanting radials each 7m long. With a 12m Spiderpole,
this would place the feedpoint 5m (16 ft.) in the air. Then run the 3 legs
to a fence or anywhere.
The antenna will work with 1, 2, or 3 radials. The more the merrier.
However in order to answer "how well it works", I have to ask "how well does
it work what?"
Working DX is one case. Working local 40m stations during the day is quite
another.
If you want to work 40m and space is a problem, one antenna I have used and
was happy with is what I call the 1-Arm Bandit. The idea was proposed by
Les Moxon long ago. It is a slightly extended quarter wavelength vertical
with a single folded radial. This saves a lot of space. You will find a
full description here:
http://www.dj0ip.de/vertical-antennas/40m-minimum-space/
Over the years I have had plenty of people in your situation ask me what to
do.
My most popular suggestion by far and away has been the openwire-fed short
vertical dipole using the 12m Spiderbeam fiberglass pole. This antenna will
work very good on 40 thru 10m and even get you on 80m with a useful signal.
See: http://www.dj0ip.de/my-favorite-antennas/all-bands-vertical/
It needs a matchbox and you can try various auto tuners. The auto tuners
should work on 40 thru 10. Not sure if they will work on 80m.
I have matched this with a Johnson Viking Matchbox, MFJ-974 Balaonced
Matchbox, KW-EZEE Match, and often using an external 1:1 Guanella balun and
a simple T-Match (Ultramatch) matchbox. (Of these, the MFJ-974 worked best
- found a match on all bands all the time).
The beauty is, you can put it up and down in minutes if you are allowed to
leave a stake in the ground all the time.
Simply strap it to the stake with a couple of small straps, or tie it with
rope.
Again Doc, please tell us what bands, how much power, and where you wish to
work, then we can possible come up with some other ideas for you.
73 - Rick, DJ0IP
(Nr. Frankfurt, Germany)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Doc
Sent: Sunday, November 06, 2016 1:23 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Fiberglass poles?
Rick, wow what a useful and appreciated response. A quick question = how
well do the so-called "inverted WYE" wire verticals perform? I don't have
nearly enough room in my tiny yard even for 16 or 32 buried radials. In
fact, I will probably have to extend the counterpoise wires at the time of
operation. We live in a rental flat, though luckily on the ground floor.
PS You may have already answered the question, but I have to open mail in a
cell phone (g). Tough for me to read with my shaky Parkinson's hands and
arms.
Thanks and 73,
--Doc/K0EVZ
On Nov 5, 2016 5:25 PM, "rick@dj0ip.de" <Rick@dj0ip.de> wrote:
> Doc, I forgot one VERY important point: DO NOT USE CARBON-FIBER POLES
> for vertical antennas. Running a wire snug against them results in a
> significant amount of loss, often as much as 10dB.
>
> Therefore always use pure fiberglass poles for vertical antennas.
>
> That point does not apply when you are using the pole the hang a
> horizontal dipole from.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt, Germany)
>
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of
> rick@dj0ip.de
> Sent: Sunday, November 06, 2016 12:22 AM
> To: 'Discussion of Ten-Tec Equipment'
> Subject: Re: [TenTec] Fiberglass poles?
>
> Doc,
>
> You will find a good selection of plans for wire verticals on my web site.
> http://www.dj0ip.de/vertical-antennas/
>
> All of these antennas have been built and used by one or more of the
> Spiderbeam team members.
> They are all field proven and many DX-peditions use them. I know that
> for a fact because I sponsor them and they send me pictures.
>
> These are quick and easy antennas to build. Of course the purest
> might want to optimize the feedpoint impedance to get a lower
> indication the SWR bridge, but that doesn't bring anything in
> performance. Performance is a function of two factors: 1) the height
> of the vertical radiator (radiation
> resistance) and 2) the efficiency of the ground network (radials)
> under it.
> Many of these antennas have an SWR of 2:1 or higher and they work just
> fine like that.
>
> A couple of rules to remember when working with fiberglass poles:
>
> 1) NEVER drill holes in a thin wall telescoping fiberglass pole;
> that's the best way to break them.
>
> 2) Best practice is to mount the retracted pole securely to something
> (i.e., long wooden ground stake), attach the wire to the top segment
> of the pole, and then push (telescope) the segments up, one after
> another. If you mount everything to the fully extended pole when it
> is laying on the ground, then try to pivot it up, it may break.
>
> 3) Guy lines should be thin rope and kept light (2mm Kevlar is
> perfect); they should always have a little slack in them, not be pulled
tight.
>
> 4) Spiral the wire around the pole on its way to the ground, with
> about one turn every 2 to 3 ft. This reduces flopping in the wind.
>
> 5) When pressed tightly against the pole, it tends to reduce the
> velocity factor of the wire by about 0.01. Example, if the vf of the
> wire is normally 0.98, then it will be about 0.97 when snug against
> the pole. So your radiator will be a little shorter. Regardless,
> start with full size and trim to resonance.
>
> 6) A quarter wavelength 80m vertical, 67' long, fits easily onto the 60'
> Spiderbeam pole, due to the reduced vf and the spiraling of the wire.
> Start
> with the normal full length of wire (according to the formula) then as
> you approach the bottom of the pole, wind the wire a bit closer
> together (2 turns per ft. for the bottom 5 ft.). The antenna will be
resonant too low.
> Unwind a little wire, space the turns a little farther and trim off a
> little to raise resonance.
>
> 7) Though traditionally we have used 1/4 wavelength radials, they may
> be shorter (as short as 1/8 wavelength) and though it is better to
> have them all the same length, that is not absolutely necessary. 24x
> 1/8 wavelength radials will give you better performance than 12x 1/4
> wavelength radials and uses the same amount of wire.
>
> 8) If you use elevated radials, you will find it works "OK" with just
> one radial, better with two, a little better with 3 but more than 4
> doesn't buy much more gain. Each elevated radial is usually as good
> as 6 ground mounted radials (YMMV). However these radials must all be
> the exact same length and resonant 1/4 wavelength long.
>
> Rumor has it that with each fiberglass pole, Scott is throwing in a
> bag of sunspots... though I haven't confirmed this.
> Check here: http://www.spiderbeam.us/index.php?cat=c2
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt, Germany)
>
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Doc
> Sent: Saturday, November 05, 2016 9:27 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] Fiberglass poles?
>
> Barry, thanks a lot for this feedback re Spiderbeam. I have had some
> questions about the cost, which seem too low for such length.
>
> PS Could you send me the formula for making up some wire verticals?
>
> 73,
> Doc/K0EVZ
>
> On Nov 5, 2016 1:46 PM, "Barry N1EU" <barry.n1eu@gmail.com> wrote:
>
> > The Spiderbeam poles are also worth considering. Our good friends
> > W4PA and DJ0IP are intimately involved.
> >
> > 73, Barry N1EU
> >
> > On Sat, Nov 5, 2016 at 3:20 PM, Doc <k0evzdoc@gmail.com> wrote:
> >
> > > What has been your experience with the MFJ or Jackite collapsible
> > > fibreglass poles, either 33' or 43' in length? I have been
> > > considering a purchase in order to construct a wire vertical.
> > >
> > > Would really appreciate hearing from you, please.
> > >
> > > GL in the SS!
> > >
> > > 73,
> > > --Doc/K0EVZ
> > > _______________________________________________
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> > >
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