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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 THESE FORMULAS BELOW FOR
CALCULATING: one leg = 630/freq mhz
= ft ( multiply by 2 for total length ) 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 BEAMon 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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