EH ANTENNA : una truffa facente leva sul possesso di brevetto
RF Magician
internazionale posta in essere da un manipolo di "radioamatori"
americani, britannici, egiziani ed italiani.
Trattasi di una vera e propria associazione a delinquere
internazionale finalizzata alla truffa.
La truffa consiste nel vendere un "prodotto" (ANTENNA EH)
dimostrabilmente inutile che viene fatto passare per utile ed efficace
fornendo a supporto e garanzia della sua presunta efficacia soltanto
il fatto che il "prodotto" sia protetto da "brevetto d'invenzione
industriale" statunitense. QUESTA É UNA TRUFFA CHE SFRUTTA L'IGNORANZA
DEGLI ACQUIRENTI. Infatti pochi sanno che la funzione legale di un
brevetto d'invenzione non certifica la bonta' della presunta
invenzione ma semplicemente attesta che colui il quale ne ha ottenuto
il brevetto e' stato il primo a depositare una richiesta di brevetto
per quel determinato "ritrovato" e conseguentemente l'unico ad avere
diritto a sfruttarne le applicazioni commerciali o poterne cedere i
diritti per il potenziale sfruttamento commerciale del "bene"
brevettato.
In sintesi:
il "brevetto" e' solo garanzia di originalita' dell'idea e NON e'
garanzia di della sua bonta', ne' della sua efficacia e ne tanto meno
delle prestazioni.
L'OTTENERE DANARO DALLA VENDITA DI UN PRODOTTO DA PARTE DI UN
VENDITORE CHE GARANTISCE L'EFFICACIA DELLO STESSO SOLO PERCHE' IL SUO
PRODOTTO E' BREVETTATO E' SEMPLICEMENTE UNA TRUFFA, CIO' PERCHE' IL
PRODOTTO STESSO NON RISPECCHIA
QUANTO PROMESSO DAL VENDITORE ED IL VENDITORE LO HA CEDUTO CON
L'INGANNO.
Questo infatti e' quanto perpetrato attraverso il sito
http://www.eh-antenna.com ove non si fa altro che alludere al brevetto
come garanzia della bonta' del loro "prodotto" (ANTENNA EH)!!!
"WELCOME TO THE WONDERFUL WORLD OF EH ANTENNAS
For more than 120 years all antennas have been Hertz antennas, except
the Crossed Field Antenna. In the future all antennas will be EH
Antennas. How can this bold statement have any basis in fact? It is
the purpose of this web site to present information not previously
available that not only will convince the reader that using an EH
Antenna provides so many advantages that the use of any other antenna
places limits on his communications system. Fortunately, any antenna
can be converted to an EH Antenna with a minimum of effort.
We have been working with the EH Antenna concept for some time and
filed a patent covering small EH Antennas in 1998. We have filed an
additional patent clarifying the scope of the original patent,
extending it’s coverage such that any antenna can be converted
to an EH Antenna and be under the umbrella of the patent. The first
patent is entitled "E H Antenna", patent number US 6,486,846 B1.
Filing of this patent in other countries is in process in accordance
with the international PCT.
We will manufacture and sell EH Antennas only for AM Broadcast.
However, we will license various companies to manufacture and sell EH
Antennas for all other applications.
Ted Hart W5QJR Inventor and CEO EH Antenna Systems
George Jones KA4Q President, AM Broadcast Division, EH Antenna
Systems"
ED ANCORA SUL SITO http://www.eheuroantenna.com/ (IK5IIR e IZ5EEP)
"... dopo 120 anni, abbiamo pensato fosse ora di cambiare ...
... un nuovo concetto per generare l'onda elettromagnetica, 120 anni
dopo l'invenzione di Heinrich Hertz ... "
(IK5IIR e IZ5EEP)
Phone ++39 0587 606122 Fax ++39 0587 608634
Address Via Volterrana, 208/1 I-56033 Capannoli (Pisa) ITALY
E-mail in...@eheuroantenna.com
star...@arnoelettronica.com
Hately; Maurice C. (1 Kenfield Place, Aberdeen AB1 7UW, GB3);
Kabbary; Fathi M. (2 Okasha Street Flat 15, Dokki, Cairo, EG)
nell'Ottobre del 1992 hanno ottenuto il seguente n 5,155,495
6,486,846
Hart November 26, 2002
Hart; Robert T. (120 Windsor Dr., Eatonton, GA 30124)
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United States Patent 6,486,846
Hart November 26, 2002
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=6,486,846.WKU.&OS=PN/6,486,846&RS=PN/6,486,846
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E H antenna
Abstract
In an antenna system for transmitting and receiving, in association
with a radio device, electromagnetic radiation has an E-field
component and an H-field component. The electromagnetic radiation
corresponds to a radio frequency power signal having a current and a
voltage at a radio frequency. The antenna system includes a first
radiating element and a second radiating element, each comprising a
conductive material. The second radiating element is spaced apart
from, and in alignment with, the first radiating element. A phasing
and matching network is in electrical communication with the first
radiating element, the second radiating element and the radio device.
The phasing and matching network aligns the relative phase between the
current and the voltage of the radio frequency power signal so that
the H-field component of the corresponding electromagnetic signal is
nominally in time phase with the E-field component.
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Inventors: Hart; Robert T. (120 Windsor Dr., Eatonton, GA 30124)
Appl. No.: 576449
Filed: May 23, 2000
Current U.S. Class: 343/773; 343/775; 343/807; 343/822; 343/859;
343/860
Intern'l Class: H01Q 009/24
Field of Search: 343/773,774,822,852,860,808,840,859,821,807
--------------------------------------------------------------------------------
References Cited [Referenced By]
--------------------------------------------------------------------------------
Foreign Patent Documents
1284727 Aug., 1972 GB.
Primary Examiner: Wimer; Michael C.
Attorney, Agent or Firm: Bockhop & Reich, LLP
--------------------------------------------------------------------------------
Claims
--------------------------------------------------------------------------------
What is claimed is:
1. An antenna system for transmitting and receiving, in association
with a radio device, electromagnetic radiation having an E-field
component and an H-field component, the electromagnetic radiation
corresponding to a radio frequency power signal having a current and a
voltage at a radio frequency, the current and the voltage each having
a phase, the antenna system comprising:
a. a first radiating element comprising a conductive material;
b. a second radiating element comprising a conductive material, the
second radiating element spaced apart from and in alignment with the
first radiating element; and
c. a phasing and matching network, in electrical communication with
the first radiating element, the second radiating element and the
radio device, that aligns the relative phase between the current and
the voltage of the radio frequency power signal so that the H-field
component of the corresponding electromagnetic signal is nominally in
time phase with the E-field component, the phasing and matching
network including:
i. a first reactive element of a first type that electrically couples
a first terminal of the radio device to the first radiating element;
ii. a second reactive element of a second type that electrically
couples a second terminal of the radio device to the first radiating
element;
iii. a third reactive element of the first type that electrically
couples the second terminal of the radio device to the second
radiating element; and
iv. a fourth reactive element of the second type that is electrically
in parallel with the third reactive element.
2. The antenna system of claim 1, wherein the radio device is a
transmitter.
3. The antenna system of claim 1, wherein the radio device is a
receiver.
4. The antenna system of claim 1, wherein the first type of reactive
element comprises an inductor and wherein the second type of reactive
element comprises a capacitor.
5. The antenna system of claim 1, wherein the first type of reactive
element comprises a capacitor and wherein the second type of reactive
element comprises an inductor.
6. The antenna system of claim 1, wherein the first radiating element
and the second radiating element each comprise a cylinder.
7. The antenna system of claim 1, wherein the first radiating element
and the second radiating element each comprise a conic section.
8. The antenna system of claim 7, wherein each conic section includes
a narrow end and a wide end, the narrow end of the conic section of
the first radiating element being disposed adjacent to the narrow end
of the conic section of the second radiating element.
9. The antenna system of claim 7, wherein each conic section includes
a narrow end and a wide end, the antenna system further comprising a
first cover disposed so as to cover the wide end of the conic section
comprising the first radiating element and a second cover disposed so
as to cover the wide end of the conic section comprising the second
radiating element.
10. The antenna system of claim 1, further comprising a reflective
shape disposed around the first radiating element and the second
radiating element so as to reflect a portion of any electromagnetic
radiation emanating from between the first radiating element and the
second radiating element along a preselected direction.
11. A method of transmitting and receiving, in association with a
radio device, electromagnetic radiation having an E-field component
and an H-field component, the electromagnetic radiation corresponding
to a radio frequency power signal having a current and a voltage at a
radio frequency, the current and the voltage each having a phase,
comprising the step of aligning the relative phase between current and
the voltage of the radio frequency power signal so that the H-field
component of the corresponding electromagnetic signal is nominally in
time phase with the E-field component, whereby the aligning step
includes the following steps:
i. coupling a first terminal of the radio device to a first radiating
element with a first reactive element of a first type;
ii. coupling a second terminal of the radio device to the first
radiating element with a second reactive element of a second type;
iii. coupling a second terminal of the radio device to a second
radiating element with a third reactive element of the first type; and
iv. placing a fourth reactive element of the second type electrically
in parallel with the third reactive element.
12. The method of claim 11, further comprising the step of directing
the radio frequency, power signal from a transmitter to an antenna
having said first radiating element and said second radiating element,
thereby generating the electromagnetic radiation between the first
radiating element and the second radiating element.
13. The method of claim 12, further comprising the step of disposing
the first radiating element so as to be in alignment with the second
radiating element.
14. The method of claim 12, further comprising disposing the first
radiating element and the second radiating element in a reflective
shape so as to direct an electromagnetic beam substantially along a
selected direction.
15. The method of claim 14, further comprising the step of choosing a
reflective shape so that the beam follows a near vertical incidence
profile.
16. The method of claim 11, further comprising the step of directing
the radio frequency power signal from an antenna having said first
radiating element and said second radiating element to a receiver.
17. The method of claim 16, further comprising the step of disposing
the first radiating element so as to be in alignment with the second
radiating element.
18. The method of claim 16, further comprising disposing the first
radiating element and the second radiating element in a reflective
shape so as to direct an electromagnetic beam substantially along a
selected direction.
19. The method of claim 18, further comprising the step of choosing a
reflective shape so that the beam follows a near vertical incidence
profile.
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Description
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to radio frequency communications and,
more specifically, to an antenna system employed in radio frequency
communications.
2. Description of the Prior Art
Radio signals usually start with electrical signals that have been
modulated onto a radio frequency carrier wave. The resulting radio
signal is transmitted using an antenna. The antenna is a resonant
system that generates an electrical field (E field) and a magnetic
field (H field) that vary in correspondence with the radio signal,
thereby forming radio frequency radiation. At a distance from the
antenna, as a result of transmission effects of the medium through
which the radio frequency radiation is being transmitted, the E field
and the H field fall into phase with each other, thereby generating a
Poynting vector, which is given by S=E.times.H, where S is the
Poynting vector, E is the E field vector and H is the H field vector.
Most conventional antenna systems are resonant systems that take the
form of wire dipoles that run electrically in parallel to the output
circuitry of radio frequency transmitters and receivers. Such antenna
systems require that the length of the wires of the dipoles be at
least one fourth of the wavelength of the radiation being transmitted
or received. For example, if the wavelength of the radiation is 1000
ft., the length of the wire must be 250 ft. Thus, the typical wire
antenna requires a substantial amount of space as a function of the
wavelength being transmitted and received.
A crossed field antenna, as disclosed in U.S. Pat. No. 6,025,813,
employs two separate sections which independently develop the E and H
fields and are configured to allow combining the E and H fields to
generate radio frequency radiation. The result is that the antenna is
not a resonant structure, thus a single structure may be used over a
wide frequency range. The crossed field antenna is small, relative to
wavelength (typically 1% to 3% of wavelength) and provides high
efficiency. The crossed field antenna has the disadvantage of
requiring a complicated physical structure to develop the E and H
fields in separate sections of the antenna.
Therefore, there is a need for a simple and compact antenna.
SUMMARY OF THE INVENTION
The disadvantages of the prior art are overcome by the present
invention which, in one aspect, is an antenna system for transmitting
and receiving, in association with a radio device, electromagnetic
radiation having an E-field component and an H-field component. The
electromagnetic radiation corresponds to a radio frequency power
signal having a current and a voltage at a radio frequency. The
antenna system includes a first radiating element and a second
radiating element, each comprising a conductive material. The second
radiating element is spaced apart from, and in alignment with, the
first radiating element. A phasing and matching network is in
electrical communication with the first radiating element, the second
radiating element and the radio device. The phasing and matching
network aligns the relative phase between the current and the voltage
of the radio frequency power signal so that the H-field component of
the corresponding electromagnetic signal is nominally in time phase
with the E-field component.
In another aspect, the invention is a method of transmitting and
receiving, in association with a radio device, electromagnetic
radiation having an E-field component and an H-field component,
wherein the electromagnetic radiation corresponds to a radio frequency
power signal having a current and a voltage at a radio frequency. In
the method, the relative phase between the current and the voltage of
the radio frequency power signal is aligned so that the H-field
component of the corresponding electromagnetic signal is nominally in
time phase with the E-field component.
These and other aspects of the invention will become apparent from the
following description of the preferred embodiments taken in
conjunction with the following drawings. As would be obvious to one
skilled in the art, many variations and modifications of the invention
may be effected without departing from the spirit and scope of the
novel concepts of the disclosure.
BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWINGS
FIG. 1 is a schematic diagram of one illustrative embodiment of the
invention.
FIG. 2 is a schematic diagram of a second illustrative embodiment of
the invention.
FIG. 3 is a schematic diagram of the embodiment of FIG. 2 with covers
added to the conic sections of the antenna.
FIG. 4 is a schematic diagram of a third illustrative embodiment of
the invention adapted for generating a substantially directed beam of
radiation.
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of the invention is now described in detail.
Referring to the drawings, like numbers indicate like parts throughout
the views. As used in the description herein and throughout the
claims, the following terms take the meanings explicitly associated
herein, unless the context clearly dictates otherwise: the meaning of
"a," "an," and "the" includes plural reference, the meaning of "in"
includes "in" and "on." As used herein, the term "in alignment with"
includes both coaxial and slightly off coaxial.
A general discussion of Poynting vector theory may be found in the
disclosure of U.S. Pat. Nos. 5,155,495 and 6,025,813, which are
incorporated herein by reference.
As shown in FIG. 1, one embodiment of the invention is illustrated as
an antenna system 100 for transmitting and receiving, in association
with a radio device 102 (such as a transmitter or a receiver),
electromagnetic radiation having an E-field component and an H-field
component. The electromagnetic radiation corresponds to a radio
frequency power signal having a current and a voltage at a radio
frequency.
The antenna system 100 includes an antenna unit 110 and a
phasing/matching network 120. The antenna unit 110 includes a first
radiating element 112 made of a conductive material such as a metal
(for example, aluminum) and a spaced-apart second radiating element
114, also made of a conductive material such as a metal. The first
radiating element 112 and the second radiating element 114 are
substantially in alignment with each other, so that both tend to be
disposed along a common axis 116. While the first radiating element is
ideally coaxial with the second radiating element, they may be off
coaxial without departing from the scope of the invention. However,
performance of the antenna may degrade as the radiating elements get
further off coaxial. Typically, the height of the antenna unit 110
need only be about 1.5% of the wavelength. Thus, the invention allows
for relatively compact antenna designs.
In the embodiment of FIG. 1, the first radiating element 112 and the
second radiating element 114 each comprise a cylinder. As will be
shown below, the radiating elements could include conic sections as
well, or many other shapes (or combinations thereof), as will be
readily understood by those of skill in the art of antenna design.
The phasing and matching network 120 is in electrical communication
with the first radiating element 112, the second radiating element 114
and the radio device 102. The phasing and matching network 120 aligns
the relative phase between the current and the voltage of the radio
frequency power signal so that the H-field component of the
corresponding electromagnetic signal is nominally in time phase with
the E-field component. The wires connecting the phasing and matching
network 120 to the antenna unit 110 should be as short as practical so
as to minimize transmission line effects. Because the E field and the
H field are substantially in phase with each other near antenna unit
110 a Poynting vector is created almost immediately near the antenna
unit 110.
In one illustrative embodiment, the phasing and matching network 120
includes a first inductor 122 that electrically couples a first
terminal 104 of the radio device 102 to the first radiating element
112 and a first capacitor 124 electrically couples a second terminal
106 of the radio device 102 to the first radiating element 112. A
second inductor 126 electrically couples the second terminal 106 of
the radio device 102 to the second radiating element 114 and a second
capacitor 128 is electrically in parallel with the second inductor
126. While one example of a reactive element circuit configuration
embodying a phasing and matching network 120 is shown in FIG. 1, it is
understood that many other circuit configurations may be used without
departing from the scope of the invention.
An important feature of the phasing and matching network 120 is that
it performs the step of aligning the relative phase between the
current and the voltage of the radio frequency power signal so that
the H-field component of the corresponding electromagnetic signal is
nominally in time phase with the E-field component. As will be readily
appreciated by those of skill in the art, the specific circuit
elements and configuration used are unimportant so long as the result
is proper performance of the phase alignment function.
In one specific example used to communicate with a signal having an
operating frequency of 7 MHz with a bandwidth of 500 KHz, the first
inductor 122 has an inductance of 17 .mu.H, the first capacitor 124
has a capacitance of 30 pf, the second inductor has an inductance of
19 .mu.H and the second capacitor has a capacitance of 42 pf. The
phasing and matching network 120 is connected to the
transmitter/receiver 102 by a coaxial cable (not shown). The first
radiating element 112 and the second radiating element 114 are each
aluminum cylinders having a height of 12 in. and a diameter of 4.5 in.
and are spaced apart by 4.5 in. It was observed that this embodiment
resulted in a system Q of(+/-3 dB bandwidth) of approximately 7.5.
In one embodiment of the antenna unit 210, as shown in FIG. 2, the
first radiating element 212 and the second radiating element 214 each
comprise conic sections that are supported by an axial non-conducting
pipe (such as a PVC pipe). In this embodiment, the electromagnetic
radiation 232 forms between the radiating elements 212 and 214 and is
directed radially away from the antenna unit 210. The angle of the
conic sections of the radiating elements 212 and 214 depends on many
factors and can vary depending on the specific application. The angle
between the operative surfaces 218 of the radiating elements 212 and
214 can be selected in a range from nearly zero degrees (forming
extremely wide diameter cones) to 180.degree. (forming coaxial
cylinders, as shown in FIG. 1). Theoretically, if the operative
surfaces are exactly parallel (such that they form parallel disks)
then the electromagnetic radiation would not escape the disks.
In one specific embodiment, used to transmit or receive a radiation
having a wave length of 934 feet at 1 MHz, the wide ends of the conic
sections have a diameter of 14.49 feet and a height of 1.95 feet each,
with a 30.degree. angle between the operative surfaces 218. In this
embodiment, the radiating elements 212 and 214 are supported by a
coaxial 8 in. PVC pipe.
As shown in FIG. 3, a first cover 316 may be added to the first
radiating element 312 to keep rain, snow and bird nests, etc., out of
the first radiating element 312. Similarly, a second cover 318 may be
added to the second radiating element 314 to keep out similar such
debris.
As shown in FIG. 4, the antenna unit 410 may be placed in a reflective
shape 430. Such an embodiment could be used in directing a beam 432 at
a selected object. Such a shape 430 could be a parabolic reflector or
some other shape (such as an inverted cone). When the beam is directed
upward by the reflective shape 430 so that the beam 432 follows a near
vertical profile, the embodiment of FIG. 4 could be used in near
vertical incidence communications.
One advantage of the antenna system of the invention is that it
responds only to true radiated signals, not to electrical noise.
Therefore, the invention increases the signal-to-noise ratio compared
to prior art systems.
The above described embodiments are given as illustrative examples
only. It will be readily appreciated that many deviations may be made
from the specific embodiments disclosed in this specification without
departing from the invention. Accordingly, the scope of the invention
is to be determined by the claims below rather than being limited to
the specifically described embodiments above.
* * * * *
( 1 of 1 )
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United States Patent 5,155,495
Hately , et al. October 13, 1992
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5,155,495.WKU.&OS=PN/5,155,495&RS=PN/5,155,495
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Radio antennas
Abstract
An antenna for a wide bandwidth electromagnetic field polarized in a
predetermined direction at right angles to the field propagation
direction includes plural metal elements that are not resonant in the
bandwidth. The metal elements are excited to transduce an electric
field in the polarization direction over the bandwidth range. The
plural elements have an extent in the polarization direction no
greater than an order of magnitude of the shortest wave length in the
bandwidth. A structure between the element, which may be either a coil
or parallel electrodes which derive a displacement current, transduces
a magnetic field having lines of flux at right angles to the
polarization and propagation directions. The electric and magnetic
fields are excited by power from the same source with phases so that
in an interaction region of the field between a pair of the metal
elements there is E.times.H synchronism and a radiation Poynting
vector having rotational E and H fields to transduce the
electromagnetic field.
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Inventors: Hately; Maurice C. (1 Kenfield Place, Aberdeen AB1 7UW,
GB3); Kabbary; Fathi M. (2 Okasha Street Flat 15, Dokki, Cairo, EG)
Appl. No.: 543768
Filed: July 18, 1990
PCT Filed: January 27, 1989
PCT NO: PCT/GB89/00080
371 Date: July 18, 1990
102(e) Date: July 18, 1990
PCT PUB.NO.: WO89/07348
PCT PUB. Date: August 10, 1989
Foreign Application Priority Data
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Feb 02, 1988[GB] 8802204
Current U.S. Class: 343/725; 343/726; 343/727; 343/728
Intern'l Class: H01Q 021/00
Field of Search: 343/725,726,727,728,729,741,866,825
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References Cited [Referenced By]
--------------------------------------------------------------------------------
U.S. Patent Documents
3521284 Jul., 1970 Shelton, Jr. 343/727.
4809009 Feb., 1989 Grimes et al. 343/726.
Foreign Patent Documents
453660 Dec., 1948 CA 343/726.
492418 Apr., 1953 CA 343/726.
Primary Examiner: Wimer; Michael C.
Assistant Examiner: Le; Hoanganh
Attorney, Agent or Firm: Lowe, Price, LeBlanc & Becker
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Claims
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We claim:
1. A radio antenna in which electromagnetic waves are radiated from a
small volume comprising two separate element systems, one of said
systems being excited for producing a high frequency electric field,
and the other of said systems being excited for producing a high
frequency magnetic field, separate feeder means driving each of said
elements systems, each of said element systems being positioned in
adjacent interactive relationship to cross stress a common interaction
zone of both said fields to create a source from which electromagnetic
waves radiate, the element system in which said electric field is
originated including means for establishing a radio frequency
potential difference across an interaction zone between two conducting
surfaces and in which the element system for establishing the magnetic
field includes two other second conducting surfaces for establishing
an intense radio frequency displacement current, and means for
applying a radio frequency potential difference of said same frequency
between the said second surfaces for establishing an intense
circulating magnetic field and causing a significant portion of the
circulating magnetic field to cross said interaction zone.
2. A radio antenna according to claim 1 further including a phasing
unit for splitting an output of a radio transmitter into two parts
having separate delay arrangements to produce synchronized electric
and magnetic fields at the interaction zone.
3. A radio antenna according to claim 2, wherein the phasing unit
includes fixed and variable phase delay circuits and at least one
tapped transformer and switch for adjusting each said part of the
output of the said radio transmitter.
4. A radio antenna according to claim 3, wherein the phasing unit has
a wideband constant phase difference circuit for low power operation
and for driving two separate power amplifiers for developing power to
provide separate feeds to the two separate element system of the
antenna so that within the interaction zone sufficient radio wave
power is synthesized.
5. A radio antenna according to claim 1 further including a single
feeder connected to one element system and a second feeder for driving
the other element system with a phase and magnitude to synthesize a
radio frequency wave at a predetermined frequency band.
6. A radio antenna according to claim 1 wherein the two separate
element systems are constructed as half structures with a conducting
surface of sufficient area that the other half structure is defined by
a virtual image thereof.
7. A antenna comprising a first set of at least two spaced elements
defining surfaces lying in end to end relationship with each other,
means for feeding radio frequency power to the set of elements for
producing an E-field between the set of elements, a second set of at
lest two spaced elements defining surfaces in face to face parallel
planes, means for feeding radio frequency power to produce a
displacement current between the second set of spaced elements for
producing an H field around the second set, the first and second
spaced elements and the means for feeding being arranged such that
there is interactive coupling between said E-field and said H-field to
produce a propagating electromagnetic radio wave.
8. An antenna according to claim 7, wherein the surfaces of said
second set of elements are positioned between the surfaces of said
first set of elements and perpendicular thereto.
9. An antenna according to claim 8, wherein the first set of elements
comprise coaxial cylinders, the second set of elements comprising
parallel circular plates.
10. An antenna according to claim 8, wherein the first set of elements
comprise plates, the second set of elements comprising parallel
plates.
11. An antenna according to claim 7 wherein the means for feeding
radio frequency power to the elements for producing at least one of
the fields comprises a coaxial feeder cable coupled through a
transformer including a ferrite toroidal core.
12. An antenna according to claim 7 wherein said first and second sets
of elements are secured and spaced by electrically insulating support
members.
13. An antenna according to claim 7 further including a ground-plane
structure wherein one of each of the spaced set of elements is
constituted by a virtual image of the other said element on the other
side of a ground plane element electrically bisecting the antenna.
14. An antenna for an electromagnetic field polarized in a
predetermined direction at right angles to the field propagation
direction, the field having a wide bandwidth range, the antenna
comprising plural metal first elements that are not resonant in said
bandwidth range excited to transduce an electric field in said
polarization direction over said bandwidth range, said plural elements
having an extent in the polarization direction no greater than an
order of magnitude less than the shortest wavelength in the wide
bandwidth range, means between said elements excited for transducing a
magnetic field having lines of flux between said elements at right
angles to the polarization and propagation directions, said elements
and means being arranged and said electric and magnetic fields being
excited by power from the same source with phases so that there is an
interaction region of said fields between a pair of said metal
elements to provide E.times.H synchronism and a radiation Poynting
vector having rotational E and H fields to transduce said
electromagnetic field, said elements including first and second metal
plates having spaced planar faces substantially at right angles to the
electric field, means for exciting the plates with voltages displaced
in phase by 180.degree. so the electric field is established between
said planar faces, a coil disposed between said plates and having
windings positioned to excite said lines of flux, and means for
exciting said coil with current from the same source which excites the
plates with a current displaced in phase by 90.degree. relative to the
voltages which excite the plates.
15. The antenna of claim 14 wherein the faces of the plates diverge
from a central region where the coil is located so that curved
electric field lines extend between the plates.
16. The antenna of claim 14 wherein said elements include first,
second, third and fourth metal plates having spaced planar faces
substantially at right angles to the electric field, means for
exciting the first and second plates with a first voltage having the
same phase and for exciting the third and fourth plates with a second
voltage having the same phase, the first and second voltages being
from the same source and displaced in phase from each other by
180.degree., a coil disposed between said plates and having windings
positioned to excite said lines of flux, and means for exciting said
coil with current from the same source which excites the plates with a
current from the same source which excites the plates with a current
displaced in phase by 90.degree. relative to the voltages which excite
the plates.
17. The antenna of claim 16 wherein the faces of the plates diverge
from a central region where the coil is located so that curved
electric lines extend between the first and third plates and between
the second and fourth plates.
18. The antenna of claim 14 wherein at least one of the metal elements
has a first surface extending (a) in substantially the same direction
as the electric field, (b) at substantially right angles to the
magnetic lines of flux and (c) at substantially right angles to the
propagation direction so that the electric field is curved as it
propagates from said first surface to a second surface of another of
the metal elements, and means for exciting the elements including said
first and second surfaces with voltages from the same source that are
displaced 180.degree. from each other.
19. The antenna of claim 18 wherein said another element including the
second surface is configured to that the first and second surfaces
extend in substantially the same direction.
20. The antenna of claim 19 wherein the first and second surfaces are
substantially planar and substantially aligned.
21. The antenna of claim 19 wherein the first and second surfaces are
cylindrical, the cylindrical surfaces having substantially the same
radii and substantially common axes.
22. The antenna of claim 18 wherein said another element has a planar
surface that extends in a plane substantially parallel to the
propagation direction.
23. The antenna of claim 22 wherein the first surface is cylindrical,
the first surface having an axis substantially at right angles to the
plane of the second element.
24. The antenna of claim 18 wherein the means to transduce the
magnetic field includes a coil disposed between said elements and
having windings positioned to excite said lines of flux, and means for
exciting said coil with current from the same source which excites the
elements with a current displaced in phase by 90.degree. relative to
the voltages which excite the elements.
25. The antenna of claim 24 wherein said another element is configured
so that the first and second surfaces extend in substantially the same
direction.
26. The antenna of claim 25 wherein the first and second surfaces are
substantially planar and substantially aligned.
27. The antenna of claim 14 wherein the means to transducer the
magnetic field comprises a capacitor having first and second
substantially parallel planar electrodes extending substantially in
the direction of propagation and substantially at right angles to the
electric field lines, and means for exciting the electrodes so that
voltages phase displaced from each other by 180.degree. are applied to
the first and second electrodes so that a displacement current
correlated with the magnetic field subsists between the electrodes.
28. The antenna of claim 27 wherein at least one of the metal elements
has a first surface extending (a) in substantially the same direction
as the electric field, (b) substantially at right angles to the
magnetic lines of flux and (c) substantially at right angles to the
propagation direction so that the electric field is curved as it
propagates from said first surface to a second surface of another of
the metal elements, and means for exciting the elements including said
first and second surfaces with voltages from the same source that are
displaced 180.degree. from each other.
29. The antenna of claim 28 wherein said another element in configured
so that the first and second surfaces extend in substantially the same
direction.
30. The antenna of claim 29 wherein the first and second surfaces are
substantially planar and substantially aligned.
31. The antenna of claim 28 wherein the first and second surfaces are
cylindrical, the first and second surfaces having substantially the
same radii and substantially common axes.
32. The antenna of claim 28 wherein the second element has a planar
surface that extends in a plane substantially parallel to the
propagation direction.
33. The antenna of claim 32 wherein the second element includes the
second electrode.
34. The antenna of claim 33 wherein the first electrode includes a
central aperture, a first cable including a first feed line extending
through the aperture and connected to said first element and a second
line connected to said second element, a second cable including third
and fourth lines connected to terminals of a primary winding having
opposite terminals respectively connected to the first electrode and
the second element.
35. The antenna of claim 34 wherein said cables are coaxial, the first
and third lines being center conductors of the first and second
cables, respectively, the second and fourth lines being shields of the
first and second cables, respectively.
36. The antenna of claim 33 wherein the first surface is cylindrical,
the cylindrical surface having an axis at right angles to the plane of
the second element.
--------------------------------------------------------------------------------
Description
--------------------------------------------------------------------------------
FIELD OF THE INVENTION
This invention relates to antennas for the transmission and reception
of radio waves for telecommunications, broadcasting sound and
television, radar, satellite communications and the like.
Known antennas usually have a single feeder connected to either a
single conductor element of approximately half a wavelength, or to a
single driven element within a group of parasitic elements as in the
Yagi-Uda array. By means of added reactive components such as
inductors, end capacitors, resonant traps and such, antennas have been
constructed with somewhat smaller dimensions than the basic half
wavelength element. Loop antennas are also known and are useful in
direction finding. However most antennas of reduced dimensions have
disappointing transmission efficiency due to the necessarily increased
circulation currents which cause large conductor losses and or
magnetic core losses.
BACKGROUND ART
The Poynting Theorem states that for any superimposed electric and
magnetic fields there must be energy flowing in the medium and thus
the phenomenon of radio wave propagation has been explained in the
presently accepted theory as the radiation of electromagnetic energy
in the form of an electric field E and a magnetic field H in a
cross-product Poynting vector E.times.H=S watts per meter squared. The
perpendicular geometric relationship and the time synchronism implied
by the above formula must be produced by any antenna which is to
radiate efficiently. Presently known antennas are probably achieving
the requirements in an uncontrolled or accidental manner.
Due to extended physical dimensions and high location above the
ground, it is probable that there is fortuitously provided in the
large volume of space a means of setting the necessary
perpendicularity and simultaneity as well as a degree of rotationality
for the fields, although the absence of these conjectures from the
present texts ought not to be used to condemn the validity of the
concept. From the large surrounding and lightly stressed volume the
comparatively weak Poynting vector progresses outwards to infinity.
THE INVENTION
In accordance with one aspect of the invention a radio antenna in
which electromagnetic waves are radiated from a small volume comprises
two first and second separate element systems respectively excited for
producing high frequency electric and magnetic fields. Separate feeder
means drives each of the element systems. Each of the element systems
is positioned in adjacent interactive relationship to cross stress a
common interaction zone of both fields to create a source from which
electromagnetic waves radiate. The element system in which the
electric field is originated establishes a radio frequency potential
difference across an interaction zone between two conducting surfaces.
The element system for establishing the magnetic field includes two
other conducting surfaces for establishing an intense radio frequency
displacement current. A radio frequency potential difference of the
same frequency is applied between two of the conducting surfaces for
establishing an intense circulating magnetic field to cross the
interaction zone.
In a preferred embodiment a phasing unit splits an output of a radio
transmitter into two parts having separate delay arrangements to
produce synchronized electric and magnetic fields at the interaction
zone. The phasing unit preferably includes fixed and variable phase
delay circuits and at least one tapped transformer and a switch for
adjusting each part of the output of the radio transmitter. The
phasing unit also preferably has a wideband constant phase different
circuit for low power operation for driving either of the separate
units. Two separate power amplifiers develop sufficient power to
provide separate feeds to the two separate element systems of the
antenna so that within the interaction zone radio wave power is
synthesized.
In another embodiment a single feeder is connected to one element
system and a second feeder drives the other element system with a
phase and magnitude to synthesize a radio frequency wave at a
predetermined frequency band.
In another embodiment, the two separate element systems are
constructed as half structures with a conducting surface of sufficient
area that the other half structure is defined by a virtual image
thereof.
In accordance with a further aspect of the invention, an antenna
comprises a first set of at least two spaced elements defining surface
lying an end to end relationship with each other. Radio frequency
power is fed to the set of elements for producing an E-field between
the set of elements. A second set of at least two spaced elements
defines surfaces in face to face parallel planes. Radio frequency
power produces a displacement current between the second set of spaced
elements establishes an H field around the second set. The first and
second spaced elements and means for feeding the radio frequency power
are arranged so there is interactive coupling between the E and H
fields to produce a propagating electromagnetic radio wave.
In accordance with one embodiment the surfaces of the second set of
elements are positioned between the surfaces of said first set of
elements and perpendicular thereto. In one arrangement, the first set
of elements comprises parallel circular plates. In another arrangement
the first set of elements comprises plates and the second set of
elements comprises parallel plates.
In one embodiment one of the fields is produced by a feed including a
coaxial feeder cable coupled through a transformer including a ferrite
toroidal core. The first and second sets of elements are preferably
secured and spaced by electrically insulating support members. A
ground-plane structure may be provided wherein one of each of the
spaced set of elements is constituted by a virtual image of the other
element on the other side of a ground plane element electrically
bisecting the antenna.
In accordance with a further aspect of the invention, an antenna for
wide bandwidth electromagnetic field polarized in a predetermined
position at right angles to the field propagation direction comprises
plural metal first elements that are not resonant in the bandwidth.
The first elements are excited to transduce an electric field in the
polarization direction over the bandwidth and have an extent in the
polarization direction no greater than an order of magnitude less than
the shortest wavelength in the wide bandwidth range. Means between the
elements transduces a magnetic field having lines of flux between the
elements at right angles to the polarization and propagation
directions. The elements and means are arranged and the electric and
magnetic fields are excited by power from the same source with phases
so there is an interaction region of the fields between a pair of the
metal elements to provide E.times.H synchronism and a radiation
Poynting vector having rotational E and H fields to transduce the
electromagnetic field. The elements include first and second metal
plates having spaced planar faces substantially at right angles to the
electric field. The plates are excited with voltages displaced in
phase by 180.degree. so the electric field is established between said
planar faces. A coil disposed between the plates has windings
positioned to excite the lines of flux. The coil is excited with
current from the same source which excites the plates with a current
displaced in phase by 90.degree. relative to the voltages which excite
the plates.
In one embodiment, the faces of the plates diverge from a central
region where the coil is located so curved electric field lines extend
between the plates.
In another embodiment, the elements include first, second, third and
fourth metal plates having spaced planar faces substantially at right
angles to the electric field. The first and second plates are excited
with a first voltage having the same phase while the third and fourth
plates are excited with a second voltage having the same phase. The
first and second voltages are from the same source and displaced in
phase from each other by 180.degree.. A coil disposed between the
plates has windings positioned to excite the lines of flux. The coil
is excited with current from the same source which excites the plates
with a current displaced in phase by 90.degree. relative to the
voltages which excite the plates. Preferably, the faces of the plates
diverge from a central region where the coil is located so curved
electric field lines extend between the first and third plates and
between the second and fourth plates.
In a further embodiment, at least one of the metal elements has a
first surface extending (a) in substantially the same direction as the
electric field, (b) at substantially right angles to the magnetic
lines of flux and (c) at substantially right angles to the propagation
direction so the electric field is curved as it propagates from the
first surface to a second surface of another of the metal elements.
The elements including the first and second surfaces are excited with
voltages from the same source that are displaced 180.degree. from each
other. Preferably, the another element including the second surface is
configured so the first and second surfaces extend in substantially
the same direction. In one embodiment the first and second surfaces
are substantially planar and substantially aligned. In a second
embodiment the first and second surfaces are cylindrical and have
substantially the same radii and substantially common axes. The
another second element may be a planar surface extending in a plane
substantially parallel to the propagation direction. In this case, the
first surface is cylindrical and the first surface has an axis
substantially at right angles to the plane of the second element. In
the further embodiment, the magnetic field is transduced by a coil
disposed between the elements and having windings positioned to excite
the lines of flux. The coil is excited with current from the same
source which excites the elements with a current displaced in phase by
90.degree. relative to the voltages which excite the elements. In this
arrangement the another element is configurated so the first and
second surfaces extend in substantially the same direction and the
first and second surfaces are preferably substantially planar and
substantially aligned.
In still another embodiment the magnetic field is transduced by a
capacitor having first and second substantially parallel planar
electrodes extending substantially in the direction of propagation and
substantially at right angles to the electric field lines. The
electrodes are excited so voltages phase displaced from each other by
180.degree. are applied to the first and second electrodes so a
displacement current correlated with the magnetic field subsists. In
this arrangement, preferably at least one of the metal elements has a
first surface extending (a) in substantially the same direction as the
electric field, (b) substantially at right angles to the magnetic
lines of flux and (c) substantially at right angles to the propagation
direction so the electric field is curved as it propagates from the
first surface to a second surface of another of the metal elements.
The elements are excited by a means including the first and second
surfaces with voltages from the same source that are displaced
180.degree. from each other. The another element is preferably
configured so the first and second surfaces extend in substantially
the same direction and the first and second surfaces are substantially
planar and substantially aligned.
The first and second surfaces are cylindrical in still another
arrangement wherein the first and second surfaces have substantially
the same radii and substantially common axes. The second element may
include a planar surface that extends in a plane substantially
parallel to the propagation direction, in which case the second
element preferably includes the second electrode. A first cable
includes a first feed line extending through a central aperture of the
first electrode. The first line is connected to the first element and
a second line connected to the second element. A second cable
including third and fourth lines is connected to terminals of a
primary winding of a transformer having a secondary winding having
opposite terminals respectively connected to the first electrode and
the second element. The cables may be coaxial so the first and third
lines are respectively center conductors of the first and second
cables and the second and fourth lines are respectively shields of the
first and second cables.
The invention is further described and illustrated with reference to
the accompanying drawings, showing embodiment by way of examples.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of an embodiment with a horizontal
coil,
FIG. 2 is a schematic elevation view of the embodiment of FIG. 1,
FIG. 3 is a circuit diagram for phasing unit for feeding an antenna
according to the invention,
FIG. 4 is a circuit diagram of a further feeder unit,
FIG. 5 is a schematic perspective view of another embodiment for
radiating of vertically polarized waves,
FIG. 6 is a schematic perspective view of a further embodiment using
capacitive effect to produce the magnetic field,
FIG. 7 is a schematic perspective view of an embodiment similar to
FIG. 6 using cylindrical elements.
FIG. 8 is a schematic perspective view of an embodiment forming a
ground plane construction, and
FIG. 9 is a schematic perspective view of the feed arrangement for an
antenna similar to that shown in FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a plan view of an elementary form of a twin feeder crossed
field antenna according to this invention. The horizontal coil 1 is
fed by feeder 2 via matching and isolating transformer 3 and carries a
radio frequency current shown by arrows indicating an anticlockwise
maximum in the cycle time. Thus upwardly directed in the center of the
coil there is high magnetic field density H from J+D'=.gradient.XH
which returns downwards all around the periphery of the coil. There
are two pairs of conducting plates 4 and 5, 6 and 7, with planes
standing vertically which are insulated from everything else but are
fed with antiphase voltage of the same frequency in pairs as shown, by
power in feeder 8 via matching and isolating transformer 9. At the
same instant in the cycle the plate pair 4 and 5 are electrically
positive relative to the plate pair 6 and 7. Thus due to the very
small dimension of the whole antenna, the propagation delay across the
interaction zones marked X and Y is negligible and so the correct
simultaneity, orthogonality and rotationality exists and Poynting
vector synthesis occurs and radio power radiates away with the
velocity of light in the directions marked S.
FIG. 2 is a diagram of the same antenna in elevation.
Detailed consideration of the phase requirement may be deduced as
follows. Sinusoidal carrier waves are being applied and electric field
E is in phase with the voltage across the plate pairs. The retardation
due to size is negligible as is the magnetic field retardation around
the coil. Thus the field H is in synchronism with the current causing
it, that is the magnetic field is in phase with the current. Current
in a coil is however always lagging by about 90.degree. relative to
the voltage across the coil due to self inductance. So, in order to
obtain phase synchronism of the fields interacting in the crossed
field antenna, the feed voltage to the coil needs to be approximately
90.degree. advanced on the feed voltage between the electrical plates.
If both transformers have identical phase characteristics, the signal
to feeder 2 must to be phase advanced by 90.degree. compared with the
voltage supplied to feeder 8. Cable lengths are only significant if
different, so for a single frequency application an electrical quarter
wavelength extra in feeder 8 would fulfil the phase requirement. By
providing a power divider so that a single transmitter supplies
approximately half the power to each of the twin feeders, the
interaction zone radiates the total power in the synthesised Poynting
vector An antenna for general radio communications requiring many
operational frequency changes must to have a phase adjusting unit.
FIG. 3 is a circuit diagram of a simple phasing unit with which the
said phase adjustment could be provided The transmitter power is split
partly into the upper capacitive path and partly into the lower
inductive path. Setting the capacitor 10 to some value will give
45.degree. advance; setting the inductor to another value will result
in a corresponding 45.degree. delay which will ensure that after
stimulating the two fields the radio wave will be correctly
synthesised in the interaction zones.
FIG. 4 shows a more sophisticated form of phasing unit which will
provide phasing for any kind of twin feeder crossed field antenna
under almost any circumstances over a wide frequency range. A switched
auto transformer 12 is connected to feeder output 88 and is preceded
by phase adjustment arrangements switchable into either sense by
switch 14, of which coarse settings are provided by the dual gang
switch 13A, 13B and a selection of cable lengths 15, and a fine
adjustment by the variable capacitor 16.
A more complex phase adjustment system, (not shown) would have a
series of two-pole change-over switches able to connect any total
combination of delay cables selected from a sequence of lengths
incremented in a 1/8, 1/4, 1/2, 1, 2, 4, 8, 16, 32 metersystem. Such a
scheme would allow a user to correct the phase of the feed to a
crossed field antenna such that a single device could be radiating
successfully at any frequency in the whole HF spectrum.
In a further preferred arrangement the phasing unit has a wideband
constant phase difference circuit for low power operation and
followed, either inside the unit or outside as two separate units, by
two separate power amplifiers which develop sufficient power to
provide separate feeds to the two electrode systems of the antenna so
that within the interaction zone sufficient radio wave power is
synthesised.
An alternative twin feeder crossed field antenna which will radiate
vertically polarized waves instead of horizontal, is shown in FIG. 5.
The antenna consists of a narrow vertical coil 17 fed from cable 2C
via matching transformer 18, and two conducting plates 19 and 20 fed
by feeder 8C via matching and isolating transformer 21. A widespread
electric field E is created in arcs from the top plate to the lower
plate and produces a cross-product with the magnetic field H rotating
in the directions indicated and thus synthesises intense Poynting
vectors S which radiate outwards in broad azimuthal angles to space.
The said antenna having several advantageous features namely a reduced
number of components and also a larger interaction volume than has the
first type according to FIGS. 1 and 2. The first feature reduces costs
and simplifies the structure. The second advantage gives enhanced
signal voltages when used in the receive mode. Furthermore, since any
one of the four input terminals (two plates and two coil terminals)
may be connected to earth it will be optimal to have the lower plate
earthed for safety as well as providing an opportunity to bond the
screens of the coaxial feeders thereto.
It is possible for transformer 21 to be dispensed with, and direct
feed from the inner conductor of feeder 8C to be connected to the
upper plate 19 with the screen remaining connected to plate 20.
As a further development of the twin feeder crossed field antenna
types which use a coil to generate the magnetic field, a further
arrangement is proposed called the Maxwell type, in which the magnetic
field is produced from an electric field displacement current located
within a capacitor. It is an arrangement which has many advantages
theoretically and practically, and allows the construction of a truly
omnidirectional vertically polarised antenna. Examination of the
Maxwell law D'=.gradient.XH where D'=.delta.D/.delta.t shows that a
changing displacement field causes a rotational magnetic field. As the
displacement current density is simply related in space (or in air) by
the formula D'=.epsilon.E' where E is the electric field intensity and
.epsilon. is the dielectric constant, it is easy to calculate that
this will be a very useful technique for HF crossed field antennas of
small size. Also it can be seen that as before, the S= E.times.H
relationship of the Poynting vector demands geometric perpendicularity
synchronism and rotational form to both fields The differentiation
with respect to time within the Maxwell law again inserts a 90.degree.
phase change but in this type it is of the opposite sign. There is a
90.degree. advance of magnetic field relative to the voltage gradient
and so there must be a 90.degree. delay in the voltage fed to the
plates of the said capacitor. The Maxwell type of crossed field
antenna requires two separate electric field stimulator plates; one
pair as in the first type to initiate the E field, and the other pair
to initiate the magnetic field by the Maxwell law The second pair are
called therefore, the D plates. In total there are four phases of
electric potential within the antenna structure: 0.degree. and
180.degree. of the E plates; 90.degree. and 270.degree. of the D
plates
FIG. 6 is a diagram of a basic form of the Maxwell type of twin feeder
crossed field antenna. Two flat plates 22 and 23, standing vertically
are insulated from other electrodes and ground and are fed by coaxial
cable 26 via matching and isolating transformer 27, thereby producing
the electric field E shown in the downwards phase. Two insulated flat
elliptical plates 24 and 25, disposed horizontally are also insulated
from earth and other electrodes and constitute the capacitor within
which a large displacement current density D' is produced by radio
frequency power arriving from feeder 28 via matching and isolating
transformer 29. The rapidly changing displacement current is then the
origin of the considerably curved H around the whole antenna in the
direction shown. In the wide interaction zones at mid height, in front
of and behind the structure, copious field crossing is present and so
considerable Poynting vector power density is generated and radio
waves propagate away at the velocity of light in the directions shown
S. The waves are vertically polarised; the horizontal polar diagram is
a figure of eight. The lower plate may be earthed and the screens of
the coaxial feeders bonded to it. The transformer 27 may be dispensed
with and a direct connection made between the inner of the feeder 26
and the plate 23.
Many variants of the Maxwell type are conceivable and they constitute
a generic family of twin feeder crossed field antennas disclosed
herein. For instance the form described in FIG. 6 could be turned
through 90.degree. and it will then generate horizontally polarised
waves and have a radiation polar diagram which is a figure of eight in
the horizontal plane.
Two further antennas of this family will b described as they are
important in having a robust structural shape as well as a vertically
polarised omnidirectional radiation which is often required in
broadcasting and communicating to mobiles
FIG. 7 is a diagram of the cylindrical form of Maxwell type crossed
field antenna. The downwards electric field E is initiated by voltage
between the hollow cylindrical conducting electrodes 30 and 31 which
are fed from feeder via matching transformer 33 The lower cylinder may
stand safely on the ground or could be formed as a flat plate on site.
The displacement current D' is stimulated upwards at the same time in
the cycle by feeding the appropriate phase voltage between the two
horizontal disc conductors 34 and 35 (having their central area
removed for space to mount transformers, feeders etc.) using feeder 36
via matching and isolating transformer 37. Should there be a
requirement to reduce weight or wind resistance, the said electrodes
and conductors may be made with alternative materials such as
conducting wire mesh, or a conducting surface applied to a plastics or
other non-conducting structural component.
FIG. 8 is a diagram of a ground plane (or half symmetry) form of the
cylindrical twin feeder crossed field antenna of the Maxwell type. The
downwards electric field E is produced by applying a voltage between
the hollow conducting cylinder 37 and the large conducting earth plane
38 with the upwards displacement current D' from the said earth plane
to the circular conducting plate 39 with a central missing area marked
39a in order to create the required rotational magnetic field H to
interact with the said E field and synthesise the Poynting vector S
radiating all round to space.
In a practical construction for the frequency range 3.6 to 30 MHz, the
cylinder 37 has a height of 25 cm and a diameter of 20 cm with the
base spaced 10 cm from the plate 39. Plate 39 has a diameter of 40 cm
and is positioned coplanar to and 5 cm distance from plane 38. The
parts may be mechanically connected by insulating pillars or foamed
plastics blocks.
The feed arrangement is shown in FIG. 9 and this has the E-field
feeder 90 connected between ground plane 38 and cylinder 37 and the
H-field feeder 91 terminating in toroidal ferrite coupling transformer
92 feeding between ground plane 38 and plate 39. It is important that
the outer conductor of feeder 91 is not electrically connected with
any part of the structure.
For weatherproofing the structure may be encased for protection but in
a preferred embodiment a louvred or apertured screen is used in
conjunction with a top cover to provide air through flow.
Twin feeder crossed field antennas of the above forms or other forms
may be made almost as small as desired. With correct time phasing, the
power radiated from the interaction zones can be made as large as
desired and is limited only by the necessary voltages at the
electrodes and the ultimate possibility of corona discharge. However
since the plates are large in area compared with the surface areas for
wire antennas the problem is of comparative insignificance. Antennas
of these types only 1/200 th of a wavelength in length (and less in
diameter) have been able to radiate 400 watts on HF with no
perceptible problems of electrode distress Calculations show that for
the magnitudes of voltage used in wire antennas, teraWatt capabilities
will be possible with crossed field antennas. There are no large
circulating currents in any conductor since nothing is in resonance.
It is a major advantage of the twin feeder crossed field antenna
system that it is broadband, and low Q. For any given antenna
radiating efficiently because it is correctly phased, the bandwidth is
very broad, firstly because of the phase-sense of frequency change
acting by the Maxwell Law is the same sense as change due to a wave on
the delay cable, secondly because the two fields are both originated
from capacitor stimulus and also change in the same phase sense,
thirdly the two fields interact in such a way as to provide a lower
input impedance in each capacitor and therefore self-optimise the
synthesis. Thus an antenna which is say 1/400 th of a wavelength
height may be expected to have a small depreciation of efficiency by a
frequency change of about plus and minus 15%.
Many of the electrical properties of the system described are not
critical. For instance the adjustments needed in the phasing unit to
produce a low VSWR in the common feeder leading will be found in
practice to be self-optimising. The magnetic field generated around
the displacement current capacitor is in the direction of curvature to
reduce the impedance experienced by the electric field generator since
the synthesised Poynting vector takes away power from the radio wave
continuously, and at no part of the cycle does the E field find its
path as impedant as normal space; it is always presented to the field
lines as a power sink as long as the magnetic field H is synchronous
For the same reasons, the H field lines flow into a low reluctance
interaction zone of a similar power sinking nature due to the
cross-curved E field in phase at all times. Only in the unproductive
zones around the antenna do the fields experience the normal path
impedance and reluctances. The crossed field antenna system is almost
an efficient "open frequency" antenna It will also receive radio
signals and so may be used in two way-radio systems.
In fact the new device is such a small sized source that many
techniques not before possible are now within easy achievement. When
used in a reflecting or phasing arrangement, the crossed field antenna
allows perceptible directivity to be attained in either transmit or
receive modes even when the waves concerned are much larger than the
reflector or array diameter.
The radio antenna may be used to radiate or receive electromagnetic
waves when mounted within or along with other conductors, or
conducting surfaces in order to reflect, direct, focus or enhance the
said radiation or fed with either constant phase related power in
parts, or varying phase power in parts so that a shaped radiation
pattern is produced by the array and may be directed in any desired
direction or directions.
The invention also relates to the use of the antenna for radio
communication through a medium comprising ground, water, air or space.
* * * * *
--------------------------------------------------------------------------------
iz8dxb
paladini della giustizia ma semmai di testimonianze che dimostrino
l'inefficacia del prodotto.
Quando fai queste affermazioni diffamatorie almeno lascia una firma
...perchè almeno quei manigoldi come li chiami tu che fabbricano quella
antenna ci hanno sottoscritto nome, cognome e dignità.
IZ8DXB
Maurizio
"RF Magician" <rf_ma...@libero.it> ha scritto nel messaggio
news:569fadf0.0307...@posting.google.com...
max
lasciare nome cognome indirizzo e (eventuale) nominativo, giuro che mi
autocostruisco una EH, la provo e poi scrivo i miei commenti ed i miei
insulti su questo gruppo.
1° ps non conosco la Eh antenna se non per la pubblicità sulle riviste del
settore e non me ne frega niente della EH antenna.O
2° ps un grande statista del passato soleva dire: "sono contrario alle tue
idee, ma ricordati che mi batterò fino alla morte per fare in modo che tu le
possa esprimere liberamente".
ciao de Max iz1aux al secolo
Massimiliano Masi
Via Galvani 13
28100 Novara
"iz8dxb" <iz8...@hotmail.com> ha scritto nel messaggio
news:FcySa.2787$t92....@news1.tin.it...
Lord Arthur / Inverse
wrote:
>E' stata portata alla mia attenzione una truffa a carattere
il tuo aver utilizzato google non ti mette affatto al riparo da una
querela per diffamazione.
Franco
> Non ci stai dicendo nulla di nuovo...e comunque non abbiamo bisogno di
> paladini della giustizia ma semmai di testimonianze che dimostrino
> l'inefficacia del prodotto.
>
> Quando fai queste affermazioni diffamatorie almeno lascia una firma
> ...perchè almeno quei manigoldi come li chiami tu che fabbricano quella
> antenna ci hanno sottoscritto nome, cognome e dignità.
Sulla dignita` avrei qualcosa da eccepire, in quando dimostrano di avere
le idee abbastanza confuse sulle equazioni di maxwell :-)
--
Franco
Wovon man nicht sprechen kann, darüber muß man schweigen.
(L. Wittgenstein)
Hy-Gain 18AVT
allo staff di Stefano Galastri,
sono un SWL del Piemonte e con i consogli di Stefano e del suo staff appunto
e con l'ausilio degli articoli di altri OM ho costruito la EH , prima quella
dei 20 metri con l'esperienza di TALINO che mi ha aiutato molto e l'antenna
va molto bene,premetto che sono un SWL molto attivo e uso una verticale per
i 20metri della HY-GAIN oltre i dipoli e che se ne dica la EH ha un punto o
due in meno della verticale e simile al dipolo,in trasmissione le abbiamo
provate con un amico OM e va bene anche se non mi interessa.
Poi ho fatto quella per i 40 metri ed è venuta non bene come l'altra perchè
ho voluto usare un tubo di plexiglass e l'ho fatta esteticamente molto bella
perchè trasparente
e inferiore come resa in ricezione ma sempre buona se teniamo presente che
un tubo di un metro sente il giappone a santiago 5 mentre un dipolo
FULL-SIZE sui 40 lo riceve a 8-9 non è male.
Dite quello che volete ma parlatene con la EH in mano perchè anche fatta
male ma l'antenna funziona (almeno in ricezione).
Questa è la mia umile considerazione e esperienza sulla EH.
Grazie della lettura
SWL 1918/TO
Marco Magnano
vedere questo sito e leggere attentamente.
Marco Magnano
"Hy-Gain 18AVT" <ldser...@libero.it> ha scritto nel messaggio
news:HZCSa.3901$t92.1...@news1.tin.it...
> e inferiore come resa in ricezione ma sempre buona se teniamo presente che
> un tubo di un metro sente il giappone a santiago 5 mentre un dipolo
> FULL-SIZE sui 40 lo riceve a 8-9 non è male.
Prova a collegare una discesa di cavo coassiale a due pezzi di metallo (di
misura casuale) delle dimensioni simili a quelle della EH.
Probabilmente riceverai allo stesso modo.
Se si tratta di una truffa non so, non credo anche perche' nessuno sta
diventando ricco, probabilmente si tratta soltanto di uno sfruttamento
della credulita' popolare, ma mi sembra ormai dimostrato che l'unica parte
attiva delle antenne EH sia il cavo coassiale (che irradia ampiamente).
Si sono visti articoli scientifici seri (non radioamatoriali, ma
professionali) che dimostrano questo concetto.
Luca IW3HQG
"La truffa consiste nel vendere un "prodotto" (ANTENNA EH)
dimostrabilmente inutile che viene fatto passare per utile ed efficace
fornendo a supporto e garanzia della sua presunta efficacia soltanto
il fatto che il "prodotto" sia protetto da "brevetto d'invenzione
industriale" statunitense. QUESTA É UNA TRUFFA CHE SFRUTTA L'IGNORANZA
DEGLI ACQUIRENTI."
Ma in realtà cosa vuol dire? Di solito una truffa è tale se c'è il fine di
ottenere denaro in cambio di nulla o di qualcosa che non è quello che si è
scelto di acquistare. Ora io l'eh l'ho fatta. Ho speso 12 mila lire, molto
tempo, e ne sono soddisfatto. Chi sostinene che bastino due piastre per
ricevere in egual maniera, lo invito fin d'ora a dimostrarmelo anche
invitandolo qui da me in veneto. Pensiamo bene sempre alla teoria. Forse è
così raffinata che ci sfugge qualcosa? magari si.
Tornando al discorso, di che truffa si parla? allora Quelli dell'eh fanno
antenne. Belle o brutte che siano, funzionanti o meno. Dicono chiaramente
come vanno (leggi sul confronto con il dipolo), ti consigliano di provare a
fartela dantoti supporto GRATUITO, e ti consigliano.
Poi se vuoi la puoi acquistare belbel che pronta. E questa sarebbe una
truffa? Credo che semmai sia ignoranza ed invidia di un prodotto che, anche
se a detta di molti, non è strepitoso, funziona dignitosamente.
Sapete quante antenne funzionano male? e sapete quante cavolate sono state
fatte sulle antenne per farle andar bene? Milioni... tondini di qui di li,
radiali di ogni forma bobine, ecc. e allora? ci sono antenne che dichiarano
guadagni folli e non è vero assolutamente. E sono brevettate. Allora sono
truffe perchè hanno il brevetto?
Che ignoranza caprina....
Io son contento della EH, credo sia un'idea intelligente, poco costosa e
efficace. Credo sia un'antenna non ottima per essere la primaria ma
sicuramente vale la pena di averla.
Mi auguro che chi abbia scritto l'articolo in prima battuta non sia una
rdioamatore, altrimenti me ne vergognerei.
Saluti
--
____________
Luca
IW3HQG
V E N E Z I A
"RF Magician" <rf_ma...@libero.it> ha scritto nel messaggio
news:569fadf0.0307...@posting.google.com...
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1
&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=6,486,846.WKU.&OS=PN/6,486,846&RS=P
N/6,486,846
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>
> References Cited [Referenced By]
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>
> Foreign Patent Documents
> 1284727 Aug., 1972 GB.
>
> Primary Examiner: Wimer; Michael C.
> Attorney, Agent or Firm: Bockhop & Reich, LLP
>
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> Claims
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http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1
&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5,155,495.WKU.&OS=PN/5,155,495&RS=P
N/5,155,495
> --------------------------------------------------------------------------
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> --------------------------------------------------------------------------
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>
> References Cited [Referenced By]
>
> --------------------------------------------------------------------------
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>
> U.S. Patent Documents
> 3521284 Jul., 1970 Shelton, Jr. 343/727.
> 4809009 Feb., 1989 Grimes et al. 343/726.
> Foreign Patent Documents
> 453660 Dec., 1948 CA 343/726.
> 492418 Apr., 1953 CA 343/726.
>
> Primary Examiner: Wimer; Michael C.
> Assistant Examiner: Le; Hoanganh
> Attorney, Agent or Firm: Lowe, Price, LeBlanc & Becker
>
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>
sorzatel
> Vediamo un po' questa frase:
cortesemente anche per rispetto di chi ti legge e senza
vergognarti leggi il link:
http://digilander.libero.it/extremenews/corso_quoting.html
cordialità
umberto in3tft
Vale
--cortesemente anche per rispetto di chi ti legge e senza
--vergognarti leggi il link:
--
--http://digilander.libero.it/extremenews/corso_quoting.html
--
--cordialità
--umberto in3tft
Certo che un po di cordialità in piu' non guasterebbe. E il tutto da
conoscitori del'HAM Spirit.
Vedremo di effettuare l'interlace per quotare.
Ciao.
--
Signature:
Rimuovi (remove) SPORCO per risposte (to send) EMAIL
i7phh
qualunque giustizia se quanto affermi fosse vero, ma non dai a loro la
possibilità di farsi giustizia nei tuoi confronti, dal momento che
vigliaccamente li diffami senza dire chi sei.
Gianni
i7phh
i7phh
quasi tutti ancora non sapevano che esistessero, non vanno come dicono, ma
funzionano.
Un mio amico, ormai non più tra noi, ha addirittura costruito la CFA da cui
l'EH deriva, ben 3 anni fà, molto prima che qualcuno iniziasse a parlare di
EH e simili e funzionava bene.
Prima di dire funziona o non funziona, sarebbe opportuno averne una.
73
Gianni
i7phh
DaRkFiRe
questa discussione creata da RF Magician (Mago delle RF) mi
sembra inopportuna e priva di fondamento.
Sia chiaro, non esistono antenne miracolose, ma antenne capaci
di lavorare bene in aria nonostante dimensioni di lavoro molto
piccole.
L'antenna EH così come la CFA sono antenne ad alta efficienza,
ma ciò "non vuol dire che vi faranno ascoltare in HF un pigmeo con lo
YAESU FT-817 (spalleggiabile) nella foresta sperduta del BORNEO!!!!!",
ma che potrebbero riuscirci se e solo se si trovano le condizioni
di propagazione favorevole.
Tutti sappiamo che un'antenna elementare come quella filare, risuona
perfettamente se costruita con bracci da 1/4 lambda.
Ma quanti di noi sono fortunati come me ad avere molto spazio (io 3000 mq di
terreno)
da poter sperimentare antenne del genere o magari una longwire di 200 metri?
Ecco che l'antenna EH ci viene in aiuto perchè nonostante le sue
modestissime dimensioni
(circa 85 cm per la versione per i 40 metri), ci da la possibilità di
operare
discretamente sulle bande HF e non solo.
Personalmente, nel novembre 2001 ho autocostruito grazie ai preziosi
consigli degli amici dell'ARNO ELETTRONICA la mia prima EH.
Certamente non sarà stata un granchè visto che non ho attrezzature
professionali
per la taratura ma il mio ROS a centro banda dopo 35 minuti di taratura
era sceso finalmente a 1,3:1
Appena aggaccianto il connettore dietro il mio ICOM 706 ho notato come
il rumore della radiofrequenza che dovrebbe essere normale in HF
era molto basso tanto che riuscivo ad ascoltare delle stazioni molto
lontane.
Dopo pochi secondi scansionado la banda dei 40 metri trovo una stazione
spagnola con segnale 5-9+, egli mi ricambia con lo stesso rapporto.
Da precisare che mi trovavo con potenza di circa 4W e che sia con
la mia antenna filare per i 40metri, sia con un cavo coassiale appoggiato
VICINO AD UN BIDONE DI FERRO posto sopra il tetto, sia
un'antenna simile alla CFA ma con qualche modifica, io non ero
mai riuscito a collegare la spagna poichè la mia città, Nocera Inferiore, è
posizionata sotto i Monti Lattari, ossia i monti che mi separano dalla
costiera
amalfitana.
Non in tutte le prove la EH è stata così efficiente purtroppo...questo è
vero! ma,
nella maggior parte dei casi sono riuscito a fare dei collegamenti, ma
soprattutto
ad ascoltare molto forte delle stazioni fino a quel momento mai sentite.
(L'ANTENNA EH ' STATA POSTA NELLA STESSA POSIZIONE
DELLA MASSIMA RADIAZIONE DEL DIPOLO).
Per quanto riguarda la discussione nel newsgroup, volevo ricordare a tutti
coloro che leggeranno questi commenti apparentemente costruttivi
e interessanti che NESSUNO DEGLI AMICI DELL'ARNO ELETTRONICA
HA MAI INCITATO NESSUNO ALL'ACQUISTO DEI PROPRI
PRODOTTI.
Anzi, credo che a tutti coloro che hanno avuto il piacere di contattarli
hanno
inviato tutte le info richieste per autocostruirsela comodamente a casa
propria,
proprio come ho fatto io.
Posso mandare foto agli increduli della mia prima EH, un'antenna scarna
che forse guardandola non è identica a quella commerciale ma l'importante
che il principio del VETTORE D POENTING e sui campi elettromagnetici
E ed H funzioni..
E' inutile ma necessario ricordare che comunque si sono svolte le mie prove,
in tutti i casi l'antenna EH ha avuto eccellenti risultanti in merito
all'annullamento
totale del TVI (il dipolo mi azzerrava lo schermo televisivo) e la
bassissima
soglia di rumore verso lo stadio ricevitore del mio RTX
Un detto diceva: "Se a ciò che vedi o senti non credi, come potrai credere
senza aver
visto o sentito?...Solo quando i potenti avrebbero creduto, potei credere
anch'io..."
La frase precendente tratta da un romanzo di inizio '800 si sposa bene
con questa discussione.
Buon lavoro a tutti.
Grazie della vostra gentile attenzione.
73's de Gianluigi Prospero Ferrara IZ8EWB
(Aerospace Student)
www.qsl.net/iz8ewb
"RF Magician" <rf_ma...@libero.it> ha scritto nel messaggio
news:569fadf0.0307...@posting.google.com...
> --------------------------------------------------------------------------
------
>
> References Cited [Referenced By]
>
> --------------------------------------------------------------------------
------
>
> Foreign Patent Documents
> 1284727 Aug., 1972 GB.
>
> Primary Examiner: Wimer; Michael C.
> Attorney, Agent or Firm: Bockhop & Reich, LLP
>
> --------------------------------------------------------------------------
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>
> Claims
>
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>
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> Description
>
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>
>
> --------------------------------------------------------------------------
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>
> References Cited [Referenced By]
>
> --------------------------------------------------------------------------
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>
> U.S. Patent Documents
> 3521284 Jul., 1970 Shelton, Jr. 343/727.
> 4809009 Feb., 1989 Grimes et al. 343/726.
> Foreign Patent Documents
> 453660 Dec., 1948 CA 343/726.
> 492418 Apr., 1953 CA 343/726.
>
> Primary Examiner: Wimer; Michael C.
> Assistant Examiner: Le; Hoanganh
> Attorney, Agent or Firm: Lowe, Price, LeBlanc & Becker
>
> --------------------------------------------------------------------------
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> Claims
>
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RF Magician
Hai detto bene! L'irradiazione percepibile é solo quella spuria di un
tratto ti cavo (linea di alimentazione) che si trova a lavrare in
forte regime stazionario in posizione verticale rispetto al suolo.
Quanto piú lo metti in alto quel trabiccolo, tanto piú cavo irradia e
quindi da l'impressione che vada meglio.
Non é il trabiccolo ad irradiare ma il cavo in forte regime di onde
stazionarie.
Parimenti il R.O.S. varia con il livello dal suolo per due semplici
motivi:
1)variando la distanza alla quale si pone il trabiccolo dal suolo
varia la lunguezza del cavo di alimentazione con corrispondente
variazione (quasi-ciclica) del R.O.S.
2)se invece il trabiccolo é alimentato sempre con la stessa lunguezza
di cavo, le variazioni del R.O.S. sono dovute al fatto che quanto piu'
il trabiccolo sale in alto tanto meno cavo rimane al suolo, mentre
aumenta la lunguezza del cavo stesso che inizia a prendere parte
all'irradiazione spuria (impropria) con conseguente illusione di un
miglioramento di resa del fottuto trabiccolo, nella fattispecie
"ANTENNA EH"
Ciao !
RF Magician
Il radiantismo ha bisogno di nuova linfa, le truffe di certo non
aiutano i giovani ad avvicinarsi alla Radio.
Sigmund
> Trattasi di una vera e propria associazione a delinquere
> internazionale finalizzata alla truffa.
truffa?
io un'EH non ce l'ho, ne' me la sono mai voluta costruire, visto il guadagno
che promette.
comunque, mi pare che nonostante il brevetto (che ti impedisce di chiamarla
eh antenna, in fondo, e basta) non ci sia nessun problema nell'autocostruirla.
per di piu' c'e' anche qualcuno che ti consiglia con le misure e i dettagli
costruttivi senza chiederti una lira.
truffa, per me, e' se io ti vendo un apparato dicendoti che funziona e poi
ti ritrovi con uno chassis vuoto o col classico mattone in vecchio stile nanni
loy...
andiamoci piano con le accuse, anche perche' sinceramente non mi pare che
serva a nulla farlo sul newsgroup.
se uno e' tanto imbestialito dalla cosa e ritiene che ci siano gli estremi per
l'accusa di truffa, faccia una denuncia, un esposto alla procura o cos'altro,
ma non posti *CHILI* di linee inutili, non commentate, in inglese che non
servono ad altro se non ad intasare la banda.
e infine, del tutto personalmente, ritengo che un swl possa apprezzare ben
piu' una semplice shielded loop fatta col coassiale, piuttosto che una roba
come l'EH che rimane omnidirezionale (sbaglio?) e quindi come amplifica il
segnale amplifica il rumore.
sempre IMHO.
Sigmund - Stazione HPC
myocastor coypus
> E' stata portata alla mia attenzione una truffa a carattere
> internazionale posta in essere da un manipolo di "radioamatori"
> americani, britannici, egiziani ed italiani.
>
*PLONK !!
MC
--------------------------------
Inviato via http://usenet.libero.it
IZ5FCY Roberto
vengono accettati in sede giudiziale ed acquisiti dal GIP come tali.
Se poni quanto è stato portato alla tua attenzione su carta legale ed unisci
ad esso anche gli inevitabili documenti accessori quali: Certificato di
residenza legalizzato e copia autenticata di un tuo documento di identità,
ti posso assicurare tutto il mio appoggio legale per l'inoltro ed il
sostentamento delle tue sorprendenti rivelazioni presso la Procura della
Repubblica di Pisa, che mi risulta essere il Foro territorialmente
competente.
Se non sei in grado di fare ciò, se non sei certo e/o responsabile delle tue
affermazioni, non tarderai a riconoscere che le tue sono solo offese
gratuite, calunnie aggravate dall'anonimato in sede pubblica, false come la
cartamoneta del Monopoli.
Ergo : ... un bel tacer non fu mai troppo...
Saluti da Roberto IZ5FCY
Billy
pesante...... anche se condivido pienamente la sostanza dell' istanza. L'
antenna EH non puo' funzionare o meglio è solo il cavo coassiale che
irradia... si tratta ovviamente di un rendimento poco superiore di un carico
fittizio... chi la possiede dovrebbe provare ad accorciare la linea... x
vedere veramente il disastro... e poi la RF va in giro è una cosa
fastidiosa .... uno è libero di fare quello che gli pare...magari
curandosi con le ali di pipistrello e le code di topo muschiato della
tasmania...
giurano poi che la miopia è scomparsa...dimagrito... il gatto è rientrato
a casa... . Il mondo è bello perchè è vario... e spesso e sempre più i
radioamatori sono allocchi che comprano apparati con tante lampadinette
colorate e bottoncini siglati con strani ideogrammi...fa parte del gioco...
radioamatori è solo un gioco piacevole...
de IS0ICE Robi
"RF Magician" <rf_ma...@libero.it> ha scritto nel messaggio
news:569fadf0.0307...@posting.google.com...
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1
&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=6,486,846.WKU.&OS=PN/6,486,846&RS=P
N/6,486,846
> --------------------------------------------------------------------------
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>
> References Cited [Referenced By]
>
> --------------------------------------------------------------------------
------
>
> Foreign Patent Documents
> 1284727 Aug., 1972 GB.
>
> Primary Examiner: Wimer; Michael C.
> Attorney, Agent or Firm: Bockhop & Reich, LLP
>
> --------------------------------------------------------------------------
------
>
> Claims
>
> --------------------------------------------------------------------------
------
>
>
> --------------------------------------------------------------------------
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> Description
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http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1
&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5,155,495.WKU.&OS=PN/5,155,495&RS=P
N/5,155,495
> --------------------------------------------------------------------------
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> --------------------------------------------------------------------------
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>
> References Cited [Referenced By]
>
> --------------------------------------------------------------------------
------
>
> U.S. Patent Documents
> 3521284 Jul., 1970 Shelton, Jr. 343/727.
> 4809009 Feb., 1989 Grimes et al. 343/726.
> Foreign Patent Documents
> 453660 Dec., 1948 CA 343/726.
> 492418 Apr., 1953 CA 343/726.
>
> Primary Examiner: Wimer; Michael C.
> Assistant Examiner: Le; Hoanganh
> Attorney, Agent or Firm: Lowe, Price, LeBlanc & Becker
>
> --------------------------------------------------------------------------
------
>
> Claims
>
> --------------------------------------------------------------------------
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>
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> Description
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>
Luca IW3HQG
ti invito a dimostrarmi come fa il cavo ad "irradiare" come tu sostieni.
Ti prego, se me lo spieghi te ne sarei grato, visto che sono anni che ho
studiato ingegneria e questo non me lo ha ancora insegnato nessuno!
RF in giro? non è forse che siamo circondati da RF?
Io ho provato ad accorciare il cavo e non è cambiato nulla. Semmai cambia la
vicinanza con gli ostacoli e con la terra... cosa che varia tra l'altro in
maniera + o - evidente con ogni tipo di antenna.
I miei saluti.
--
____________
Luca
IW3HQG
V E N E Z I A
"Billy" <iso...@tiscalinet.it> ha scritto nel messaggio
news:bfkemv$hhs$1...@lacerta.tiscalinet.it...
Franco
> Caro collega,
> ti invito a dimostrarmi come fa il cavo ad "irradiare" come tu sostieni.
> Ti prego, se me lo spieghi te ne sarei grato, visto che sono anni che ho
> studiato ingegneria e questo non me lo ha ancora insegnato nessuno!
Correnti di modo comune.
Luca IW3HQG
soprattutto bilanciata.
____________
Luca
IW3HQG
V E N E Z I A
"Franco" <in...@hotmail.com> ha scritto nel messaggio
news:bfmr37$gikt7$1...@ID-60973.news.uni-berlin.de...
Franco
> Trascurabili essendo una linea schermata, pulita, a basso rumore e
> soprattutto bilanciata.
La linea non ha importanza per i modi che vengono eccitati. Quello che
e` importante e` il carico (e il generatore).
Anche una linea schermata e bilanciata (che peraltro non ho mai visto in
RF) porta un modo comune che irradia
Cosa vuol dire una linea a basso rumore? E pulita?
Sigmund
>Trascurabili essendo una linea schermata, pulita, a basso rumore e
>soprattutto bilanciata.
o che linea e'?
una linea bifilare fatta con due cavi schermati?
io non l'ho mai vista. gia' initalia e' difficile trovare la linea a 450 ohm
bifilare o qualsiasi altra ladder line, trovarla addirittura fatta con due
cavi schermati mi pare un'esagerazione.
se invece fosse cavo coassiale, beh, il cavo coassiale *non* e' una
linea bilanciata, tant'e' vero che serve proprio un balun (balanced to
unbalanced) per attaccare un dipolo (bilanciatissimo) al coassiale che
evidentemente e' sbilanciato.
sul coassiale le common mode currents si formano eccome, a meno che
non si realizzi un rf choke avvolgendone qualche spira o inserendo una
bella fila di anellini di ferrite.
sul "pulita" mi chiedo che vuol dire...il coassiale sudicio non e' che
peggiora le prestazioni...a meno che non sia incrostato da cirripedi alieni
che emettono rf col loro guscio metallico e le loro zampe a bobina...;-)
il "basso rumore" probabilmente si riferisce alla buona qualita' dei materiali
che compongono il cavo. ma contro le common mode currents non c'e'
materiale che tenga...le proprieta' dei metalli sono proprieta' dei metalli.
se un pezzo di metallo e' attraversato da una corrente, irradia.
insisto sul fatto che anche se la eh funziona, non puo' essere migliore
di una piccola loop fatta col coassiale, almeno per un swl/bcl.
ciao
--
Sigmund - Stazione HPC
Sigmund
>
> ____________
> Luca
> IW3HQG
> V E N E Z I A
>
> "Franco" <in...@hotmail.com> ha scritto nel messaggio
> news:bfmr37$gikt7$1...@ID-60973.news.uni-berlin.de...
> > Luca IW3HQG wrote:
> >
> > > Caro collega,
> > > ti invito a dimostrarmi come fa il cavo ad "irradiare" come tu
> sostieni.
> > > Ti prego, se me lo spieghi te ne sarei grato, visto che sono anni che ho
> > > studiato ingegneria e questo non me lo ha ancora insegnato nessuno!
> >
> > Correnti di modo comune.
> >
> > --
> >
> > Franco
> >
> > Wovon man nicht sprechen kann, darüber muß man schweigen.
> > (L. Wittgenstein)
> >
>
Michele IZ2EAS
sulla parte ESTERNA del conduttore ESTERNO siano trascurabili, come
affermi... anzi, può essere vero il contrario. Il realtà, i problemi con il
coassiale nascono proprio dal fatto che è un sistema a TRE conduttori: il
conduttore interno, la parte interna del conduttore esterno e la parte
esterna del conduttore esterno...
73,
Michele IZ2EAS
"Luca IW3HQG" <tao...@hotmail.com> ha scritto nel messaggio
news:e2ETa.198972$lK4.5...@twister1.libero.it...
Luca IW3HQG
di sfasamento introdotto.
Pulita? si a meno che tu non ti riferisca al fatto che tutto è pieno di
rumore (saldature smd ad ultrasuoni comprese).. :-| per cui trascurabili.
certamente che si formano le common mode currents ma non influiscono (o
influiscono in maniera trascurabile) sul funzionamento dell'antenna. Il
network stesso ne taglia parte (chiaro è che parte se le porta dietro visto
la tipologia di materiali)
per un swl va bene anche una bella linea da 4mm e una bella terra...
HI
ciao
--
____________
Luca
IW3HQG
V E N E Z I A
"Sigmund" <ale...@NienteSchifezze.eml.cc> ha scritto nel messaggio
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Luca IW3HQG
Scusa se mi permetto ma non capisco?!?!?
se vuoi scrivimi in email.
Ciao
--
____________
Luca
IW3HQG
V E N E Z I A
"Michele IZ2EAS" <iz2...@libero.it> ha scritto nel messaggio
news:bfoh8m$h6j21$1...@ID-149021.news.uni-berlin.de...
RF Magician
capisce un tubo di RF ! hehehehe !
Non te la prendere Luca !
Ciao !
RF Magician
"Luca IW3HQG" <tao...@hotmail.com> wrote in message news:<ltoTa.196985$Ny5.5...@twister2.libero.it>...
RF Magician
capisce un tubo di RF ! hehehehe !
Non te la prendere Luca !
Ciao !
RF Magician
"Luca IW3HQG" <tao...@hotmail.com> wrote in message news:<ltoTa.196985$Ny5.5...@twister2.libero.it>...
Michele IZ2EAS
pelle tiene separate (e indipendenti) le correnti che scorrono sulla parte
interna del conduttore esterno da quelle che scorrono sulla parte esterna
dello stesso conduttore. Di qui la necessità, se si utilizzano sistemi
bilanciati, di introdurre il BALUN. Se hai modo di recuperare un buon libro
sulle antenne (ad es. l' ARRL Antenna Handbook) troverai dettagliate
spiegazioni.
73,
Michele IZ2EAS
"Luca IW3HQG" <tao...@hotmail.com> ha scritto nel messaggio
news:ToVTa.201353$Ny5.5...@twister2.libero.it...
Sigmund
> la bilanciatura era carico - generatore visto il network adottato ed il tipo
> di sfasamento introdotto.
il *bilanciamento* di cui parlavi riguardava la linea di trasmissione...
mi dici che linea di trasmissione hai?
> Pulita? si a meno che tu non ti riferisca al fatto che tutto è pieno di
> rumore (saldature smd ad ultrasuoni comprese).. :-| per cui trascurabili.
scusa, com'e' che mi rispondi a una domanda con un'altra domanda?
forse nell'ironia ho perso chiarezza: io volevo sapere che significa "linea
pulita".
> certamente che si formano le common mode currents ma non influiscono (o
> influiscono in maniera trascurabile) sul funzionamento dell'antenna.
alla faccia del trascurabile...sulla base di cosa le valuti?
il modo di annullarle c'e', prova a fare un bel choke o a mettere un bel po' di
anelli di ferrite sulla linea e poi prova a ricontrollare l'efficienza della eh.
> per un swl va bene anche una bella linea da 4mm e una bella terra...
beh, allora per un om va bene anche una gp...
che discorsi sono?
io dicevo che una loop non puo' essere peggiore. concordi?
Luca IW3HQG
non voglio polemizzare. Provala e poi mi dici. Io sinceramente non ho
ritenuto necessario l'applicazione anelli di ferrite per la presenza del
network. cmq chi lo sa proverň...
Sicuramente una loop č lili. perň č ENORMEMENTE piů grande.
Ciao
--
____________
Luca
IW3HQG
V E N E Z I A
"Sigmund" <ale...@NienteSchifezze.eml.cc> ha scritto nel messaggio
news:diTI/$n...@news.cis.dfn.de...
> "Luca IW3HQG" <tao...@hotmail.com> wrote in
<okVTa.201056$lK4.5...@twister1.libero.it>:
> > la bilanciatura era carico - generatore visto il network adottato ed il
tipo
> > di sfasamento introdotto.
>
> il *bilanciamento* di cui parlavi riguardava la linea di trasmissione...
> mi dici che linea di trasmissione hai?
>
> > Pulita? si a meno che tu non ti riferisca al fatto che tutto č pieno di
Luca IW3HQG
guardare da che pulpito viene la predica....
ciao !
--
____________
Luca
IW3HQG
V E N E Z I A
"RF Magician" <rf_ma...@libero.it> ha scritto nel messaggio
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Luca IW3HQG
Padova, 354063 TC
vedi tu cosa studiavo... ;-))
Ciao
--
____________
Luca
IW3HQG
V E N E Z I A
"RF Magician" <rf_ma...@libero.it> ha scritto nel messaggio
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Luca IW3HQG
ok questo è un altro discorso. Come sai, su un cavo coassiale anche
pessimo l'effetto pelle, incide al massimo per il 15% essendo 10 volte lo
spessore del materiale < raggio < 100 volte lo spessore. circa.
Ora non dilungandoci su formule inapplicabili vista la grossolaneità
dell'apparecchiatura, considerando la frequenza e la potenza in uso, non
credi sia trascurabile? o meglio non credi che sia trascurabile se
confrontato ad esempio con l'adattamento?
Ciao
--
____________
Luca
IW3HQG
V E N E Z I A
"Michele IZ2EAS" <iz2...@libero.it> ha scritto nel messaggio
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IK3MLF
--
IK3MLF
Claudio
Padova
Michele IZ2EAS
mi spiace ma sei in errore. L'esistenza delle correnti di "modo comune" sul
conduttore esterno dei coassiali è un fenomeno risaputo da MOLTO tempo e
incontrovertibile. Ripeto, è alla base dell'esistenza stessa dei balun:
se non forzi la corrente ad "entrare" nel coassiale, c'è il rischio concreto
che questa scorra sulla parte esterna della calza; se questo succede, il
coax smette di essere solo una linea di trasmissione e diventa parte
integrante dell'antenna, ossia IRRADIA.
Ciao,
Michele IZ2EAS
"Luca IW3HQG" <tao...@hotmail.com> ha scritto nel messaggio
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Luca IW3HQG
insisto, quello che dici è vero, in parte. Certo che il coassiale
potrebbe, e dico potrebbe irradiare se non si adatta la linea carico e
generatore; Le correnti di modo comune ci saranno sempre, più o meno
significative. Nell'impiego con antenne tradizionali, il cavo di suo irraria
così poco che è trascurabile.
Ti faccio un esempio diverso; hai presente i cavi si rete per pc? adottano
l'rj58 o giù di li... e quando non sono ataccati ad una scheda di rete hanno
un "tappo" che chiude la trasmissione. Hai un'idea della freq e del tipo di
trasmissione che viene effettuata dentro questa linea trasmissiva? e mica
irradia poi così tanto!?!?!? senno sai che bella frittata di dati!
Per piu ragioni l'effetto pelle in condizioni di adattamento del carico va
via via, sommandosi, ad elidersi, lasciando un effetto trascurabile.
Ciao
--
____________
Luca
IW3HQG
V E N E Z I A
"Michele IZ2EAS" <iz2...@libero.it> ha scritto nel messaggio
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Franco
> Ciao Michele,
> insisto, quello che dici è vero, in parte. Certo che il coassiale
> potrebbe, e dico potrebbe irradiare se non si adatta la linea carico e
> generatore;
Adattamento di impedenza del carico/sorgente e bilanciamento sono due
cose indipendenti.
Ciao!
Michele IZ2EAS
mi spiace, ma dici cose senza senso.... adattamento e sbilanciamento sono
due cose indipendenti... dici di aver studiato ingegneria.. non dovresti
quindi aver problemi a prendere un buon libro sulle antenne (ad es. l'ARRL
Antenna Handbook) e a leggerlo... altrimenti qui andiamo avanti con discorsi
da bar...
Ciao,
Michele IZ2EAS
"Luca IW3HQG" <tao...@hotmail.com> ha scritto nel messaggio
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Sigmund
> non voglio polemizzare. Provala e poi mi dici. Io sinceramente non ho
> ritenuto necessario l'applicazione anelli di ferrite per la presenza del
> network. cmq chi lo sa proverň...
>
> Sicuramente una loop č lili. perň č ENORMEMENTE piů grande.
enormemente?
per la ricezione puoi benissimo realizzare delle shielded loop a 1/16
lambda...
non e' poi cosi' enormemente piu' grande.
e di sicuro funziona meglio perche' e' direzionale e ha la possibilita'
di annullare molto le interferenze trasversali.
questo, per quel che ne so io (ma potrei sbagliarmi) la eh non lo puo' fare.
scusa, ma resto con la mia loop.
Luca IW3HQG
Grazie lo stesso per la discussione sicuramente creativa.
Ti consiglio di costruirti un EH, fare le prove, verificare i dati e dirmi
se ho torto...
Adattamento e sbilanciamento sono sicuramente 2 cose separate. Ma le
conclusioni sono quelle che ti ho riportato. Se vuoi un po' di teoria,
semmai ne avessi bisogno (ma dubito!), ci sentiamo via email...
Ciao e a presto!
--
____________
Luca
IW3HQG
V E N E Z I A
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