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MULTIBAND ONE ELEMENT VEE BEAM BY LA0HV
PETER OF NORWAY ---
LA0HV EXPANDS
ON A GREAT DESIGN!
These
instructions for the multiband one element Vee beam were taken
from
various emails from Peter, LA0HV with added comments by the original
designer of the
ONE ELEMENT VEE BEAM,
Darrell, KB4XJ
Some contents edited for clarity.....excuse any spelling
errors...
English is not Peter's native language.
A Six Band One Element
"Beam"!
20 meters thru 6...cool!
THE ANTENNA!
It
really turned my antenna farm upside down! And what a relief.
My wife
loves me again!
It reduced the antenna farm from several Quads and 3
element junior beams for several bands into the latest one element
design.
A 6 band one element horizontal V-beam covering 20, 17, 15, 12,
10 and 6 meters!
Giving from 2.1 dBd (that’s over a dipole) on 20
meters to 10.8 dbd on 6 meters."
Design is simple:
Take a
Double Extended Zepp design for 6 meters using 1/2 inch or larger element
material such as EMT, copper or aluminum. Copper is heavy! DO NOT USE WIRE
(design freq. 51.110 MHz - "down under DX window")
Each element will be
12.33 ft per side.. Feeder must be 400-600 Ohm ladder wire for at least
2.64 ft. ( See Design calculator below
)
Mount it in a 90 degree angle just like the "KB4XJ" Horizontal
V-beam shape.
(I have not experimented with any other angles)
Now
connect a 4 ft 400 Ohm ladder wire.
Connect a 4:1 CURRENT balun at the
end of the ladder line (balun design must cover 6 meters)
Connect a
remote tuning unit directly to
the balun (ATU must cover 6 meters) for example, the LDG RT11
ATU. A GREAT TUNER!
The ATU is not a good solution for "normal" beams,
because you cant tune all the other elements so easy.
But this is a ONE
element beam so it WORKS GREAT!
Connecting a tuner directly at the feed
point (the balun) will give a TRUE MATCH, not just a happy
transmitter.
(Don't use a "by the rig" tuner, it won't do
well).
Look at the dimensions and GAIN of this antenna:
On 20m:
One element + wire is 1/4 wave. Gain: 2.1 dBd. Fb > 18 dB
On 17m:
Almost a 1/2 wave dipole. Gain: 2.8
On 15m: 1/2 wave dipole. Gain: 3.3
dBd
On 12m: A little longer: 4.0 dBd
On 10m: The antenna is a little
out of band but the Balun and RT11 tuner does the job. Gain: 5.8 dBd
On
6m: EDZ v-beam. Gain: 10.8 dBd. Fb > 25 dB
ALL WITH ONE ELEMENT
!!!!!!
Now isn't that cool!
Vy 73 LA0HV, Peter
Horizontal V-Beam
Diagram >>
Use this
handy calculator for your experiments:
(You must allow your browser to
run blocked content,
scripts and Active X controls to use
calculator)
OR USE THESE
FORMULAS:
one leg = 630/freq
mhz = ft
ladder line = 135/freq mhz = ft
Here is
the basic "theory":
The TriDouble dipole has two
elements of 3/4 wavelength each.
It has resonance at the design freq
but the impedance is high (500 Ohm) and the reactance/inductance value
changes greatly when you change frequency.
To compensate for this
you shorten the element length a bit and add open wire, 400-600 Ohm (not
critical). This will decrease impedance to 200 Ohm at the design
frequency.
This is why I use a 4:1 Current balun (must be a current
balun).
This is the Extended Double Zepp, EDZ design parameters:
Length of each element: 0.64 x l
Minimum length of ladder wire:
0.137 x l
Now the great side effect is, that the antenna will work
as good as, or
better than a dipole at any frequency higher than the
frequency that match a 1/4 wavelength at one of the elements.
Now using
an open wire feeder, it will also work at the lowest freq and up,
corresponding to a 1/4 wavelength, when you add the element length to the
wire length. But now of course, gain will decrease because the ladder wire
will be a part of the antenna.
Now the EDZ will be easily matched with
a remote ATU that can handle rapidly changing reactance/inductance values.
A remote ATU that can handle swr of 1:10 will do the work
easily.
Back to the V-beam
design:
The EDZ-V-beam with design freq at 51.110 MHZ will
work with very high forward gain at the design freq, and as a normal
"KB4XJ" V-beam at the 15 meter band (look at the element length).
Using open wire feed, minimum 4 ft (longer is Ok, but remember it is a
part of the antenna at frequencies under 21 MHz), will give an easy match
from 14 MHz and up.
Conclusion: The trick is to use
open wire, a 4:1 balun and a Remote ATU like the LDG RT11 TUNER connected
directly to the balun.
Vy 73, Peter
LA0HV
THE LATEST
INFORMATION
Emails RECEIVED AS OF (11-12-02 ) from Peter LA0HV and
Darrell KB4XJ
Hi Darrell & Don.
I just finished the last
experiment of the year. It's snowing heavily now in Norway, 1 ft per hour!
Minus 10 deg Celsius .... Brrrr
Last experiment revealed something
very interesting about the current in the elements of the V-Beam:
I
made the KB4XJ 15m V-Beam design using thin wire, same length and
angle.
This happened: Field strength measurement now showed a major
back loop and a decrease of forward gain (almost no front to back). You
can say that the Beam effect almost disappeared.
I then took 1.25"
kopper (copper) tubes, same length and angle, and all of a sudden I got a
V-beam again. Back loop gone, forward gain increased to almost 6 dB
!!!!!!!!!!
So .. conclusions from a freezing cold, windy Norwegian
Hill-top is:
A "fat" element is turning the design from a resonant
V-wire antenna into a Aperiodic (stable current) element V-Beam. The thick
elements are doing the same job as a terminator in a Rhombic design .
WOOOW !!!!!
Freezing smiles from LA0HV.
Vy 73
Peter
From: Darrell & Kay Koranda [mailto:kb4xj at
strato.net]
Sent: 9. November 2002 01:16
To: Peter Grun
Re:
Developing a 6 band Single element horizontal V Beam
Hi
Peter,
The Field Strength Meter and getting readings.
I checked
across the back side of the V beam and showed a field strength reading of
a .1. At the sides of the front ends power rose .5 and just inside the
ends power rose to a 1. In the near center power rose 2. and in the dead
center it was a 3. In just the field strength reading I was figuring
around 28 db difference between front to back. In the tests I made I was
using 10 watts of power. The antenna performed very good 2 years ago when
I first truly tested it on field day 2001. Field day 2002 was not as good,
problems with generator, blowing rain. Anyway back to the Horizontal V, in
my early study on long wire antennas it was noted that power was related
to one wire and that when a wire had a twin, the power doubled. Further
study of log periodic dipoles (when a log dipole is bent forward it will
have an added gain of 2.5 db., it was also found the beginning horizontal
V was a 1/4 wave. Now in my experience I found that induction between the
elements changes the resonant frequency and lowers the frequency of a
dipole and as a result you have to add 2 inches per side to make up for
the induction factor. In your 90 degrees configuration, the higher you go
in frequency the broader the front lobe should be, in that a horizontal V
at 90 degrees at 1/4 wave on design, at longer wavelengths the V angle can
be narrowed down, but the antenna does work and I wonder why it was never
truly correctly reported, not having the works of Dr John Klause at hand.
I spent 4 months researching the horizontal V antenna, and I spent over a
month refining the center mount and have the antenna and mount down to a
lean 7 pounds! Darrell KB4XJ
----- Original Message -----
From: Peter Grun
To: 'Darrell & Kay Koranda'
Sent: Friday,
November 08, 2002 9:51 AM
Subject: SV: Developing a 6 band Single
element horizontal V Beam
Hi Darrell.
The pointing right
up idea of yours is also great. I once did that experiment with a 2
element for 80 meter. For a long time I irritated me that the G5RV did not
perform well. I found out that when you are using an Inverted V type
antenna over a sandy or rocky soil, it does not work. (I live on a rocky
hill). The ground is absorbing the E-field. The reason why the Inverted v
type antennas like the G5RV works for most people, I think, is because the
Earth with a good ground-mirror soil works as a Fire Back reflector.
So
I took a 80meter dipole and mounted a reflector between the dipole and
ground, the "beam" pointing directly in thy sky. The effect was
tremendous! Within a 1000 miles range nobody understood how my signal
could "hit" them with such an extreme powerful strength. It was a 80 meter
contest winner antenna. I think that it also is a good DX antenna, the
only problem is that stations within 1000 miles is "bending" your S-meter,
so you really need extremely strong filters to be able to work in the
DX-window.
Back to your V-beam: I don't understand how it is possible
to actually get a good FB-ratio on the V-beam. I did some field strength
readings and I am still surprised!!! It's so cool! Now talking about
"cool" winter is closing in on me here in Norway so I have to wait until
April for more experiments.
Haven't got any RTTY at the moment, but
will get some equipment during the winter, I will look for you on 15
then.
Vy 73 de LA0HV, Peter
-----Opprinnelig
melding-----
Fra: Darrell & Kay Koranda [mailto:kb4xj at
strato.net]
Sendt: 7. November 2002 13:02
Till: Peter Grun
Emne:
Re: Developing a 6 band Single element horizontal V Beam
Hi
Peter, Did you do any Field Strength readings yet? That is what shocked me
with the original design of the horizontal V design on 15 meters. The very
high increase in forward field strength in the antenna and the decrease to
the rear, could hear 360 degrees but could see a noticeable increase on
the S-Meter when you rotated to the right direction. It's really nice that
the antenna can be rotated with a cheap TV rotator, I'll have to try your
modified version. I was thinking of trying another experiment but haven't
had the time to do it yet, I was thinking of pointing the V straight up
and using the sky to bounce off of or launching at a 30 or 40 degree and
up, of the two experiments I think the second may be of a better. In the
first your pulling the signal straight down out of the sky and shooting
them back up and scattering. In the second your pulling signals down in a
direction and shooting back in the same direction. The first pointed up
has the advantage of making your antenna appear to be say; 75 miles up
with nearly omni coverage. The second pointed off with a 30 or 40 degree
rise should provide longer distance. This is what I think will happen, the
extended double zepp is basically a 3/4 wave antenna shorted to 5/8 wave
with a 1/8 wave of ladder line, I have one but haven't tried it in the V
configuration yet. I have time constraints and have to go off and work. If
you operate rtty, (I operate around 21.278 MHz), my current project is
connecting my new radio, a Patcom PC 9000, to my Pakrat 232 TNC and then
to an old laptop for some portable rtty with the One Element Beam with
Solar Power. Have yet to get the charge controller for the solar panel. I
am using a string of silicon diodes to drop the voltage to 13.8 volts DC.
Got to go, good by for now, hope we can exchange information later.
Darrell KB4XJ 73's
EMAIL
DARRELL
KB4XJ
EMAIL
PETER
LA0HV
EDITORS NOTE from N4UJW:
"In the true spirit of Amateur Radio,
Peter saw the original plans for the ONE ELEMENT BEAM on
this site and saw that an improvement could be made to this fine design
which you have just seen AND HAS SHARED IT WITH ALL OF US!
EXPERIMENT!
EXPERIMENT!........ 73 N4UJW
Peter Grun LA0HV
Svinndalveien
96
Skiptvet, 1816
NORWAY
License Class: A
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