VIRTUAL GROUND MONOPOLE HF ANTENNA © 2003 Francesco Errante

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most F.A.Q.: can I drive 2 or more monopoles simultaneously, as in a fan dipole configuration, so that I can cover several HF bands?
ANSWER: Yes ! The present virtual ground RF feeding system allows you to run all the ¼ of wavelength monopoles needed to give you a general coverage of the HF spectrum, without the need for switchings. The monopoles can be arranged on both vertical and horizontal planes. All you need to deploy them is the space.
An example of that is shown in the picture that follows.

The elementary radiator

also known as the

Errante's Antenna

Patent application n. ITAPA20030020
Follow this link to verify it directly from the European Patent Office archive:
http://l2.espacenet.com/espacenet/viewer?PN=ITPA20030020&CY=gb&LG=en&DB=EPD

Remote device pictured in a typical fan-monopole quick deployment setting

Here above is the Errante's antenna laboratory prototype in a quick fan-monopoles deployment for the 20, 30, 40, 60, 80 and 160 meter bands operation.
N.B. Shown without the ABS weatherproof outer enclosure.

Freq. range of the kit: 1 to 30 MHz
RF Power: 2KW CW

Click on the thumbnails to view larger pictures

An overview of the kit while not connected to the radiator

Close-up of the local device while connected to the twinned RF lines

An example of quick deployment of the Errante's Antenna

ERRANTE's ANTENNA : what it is, how it works and how it came to be made.

VIRTUAL GROUND ¼ of wavelength MONOPOLE (HF) ANTENNA

by Francesco Errante

The Author, by means of a particular radio-electric circuitry for the suppression of anyone of the two branches of a ½ of wavelength open dipole, has previously demonstrated that, indeed, it is possible to receive and above all, transmit large radio-electric signals across the space by employing a single radiating/captating element of a physical length equal to ¼ of wavelength, without the necessity of the presence of its symmetric (see Hertzian Dipole ) or the necessity of a natural ground plane (see Marconi's Antenna ) or an artificial one made of radials or counterpoises as in the Ground Plane Antenna. The need to have the Earth or another artificial ground as an electric reference point to correctly polarize a single resonant radiator/captator of a physical length equal to ¼ of a wavelength, has been eliminated by generating a virtual ground node, the existence of which is function of the precise balancing of the of a broad-band RF transformer. ("virtual ground" is defined as a point in an electrical circuit that appears to be at ground, but is not actually attached to ground, it is therefore, a node having a 0 degree phase angle difference with respect to ground and has the same electrical potential as the Earth")
This method, however, implied a 50% dissipation of the system energy.

The invention described hereby, while exploiting the physical principal of the virtual ground node, eliminates the need for sacrificing any of the system energy.

ANTENNA RADIO RICE-TRASMITTENTE MONOPOLARE CON TERRA VIRTUALE - Antenna Errante

The solution to that problem is given by the possibility of generating the virtual ground node by recombining two radio-electric signals, identical but 180 degree out of phase between them-selves. This can be achieved by employing a broad-band flux-coupled balun transformer(9) built around a binocular type ferrite core, having a center-tapped balanced primary winding(11) for the obtainment of the said virtual ground node to be used as a zero-potential reference point for the whole of the circuit and having also a secondary winding(13) exhibiting an impedance value of 150 Ohm for the direct coupling to a ¼ of a wavelength radiator/captator(1).
The transformer(9) and the radiator/captator(1) are the essential parts of the VIRTUAL GROUND ¼ of wavelength MONOPOLE ANTENNA, they alone, infact, constitute a ¼ of wavelength monopole antenna with balanced input. However, in order for it to match the current transmission line standards, it has been necessary to provide it with a second transformer(5) capable of adapting the unbalanced coaxial antenna output of a conventional transceiver to the balanced input of this antenna transformer(9).
The RF energy transfer between the two transformers(5 & 9) is accomplished by the twinned coaxial transmission lines(7) which can be of any length but must be identical between them-selves so not to alter the original phase-angle difference between the RF signals they are meant to be carrying. Although, the value of impedance of the intermedium circuit, which comprises the primary winding of the transformer(9), the twinned coaxial lines(7) and the secondary winding of the transformer(5) can be set to any value, it turned out to be convenient adopting a standard value of 50 Ohm.

Scientific relevance:

a. it demonstrate that a single electrically conductive element of a physical length equal to ¼ of wavelength is all it takes to accomplish natural resonance and full radiation.

b. thanks to its most elementary shape and bare simplicity of the radiating element, it allows further investigation into the physics of the radiowaves. (see here)

Operational advantages:

a. the VIRTUAL GROUND MONOPOLE HF ANTENNA demonstrates that, indeed, it is possible and relatively inexpensive to implement an highly efficient way to better radiate RF energy while cutting by 50% the room needed to deploy a full-size HF antenna.

b. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a much larger bandwidth compared to conventional full-size aerials.

c. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a much stronger immunity to parasitic capacitive effects compared to conventional full-size aerials.

d. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers high resonance stability regardless of the level and inclination above the ground.

e. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a much stronger immunity to out-of-band emissions compared to conventional full-size aerials.

f. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a much stronger immunity to electrostatic charges and noises compared to conventional full-size aerials.

g. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a sharper radiation pattern than conventional full-size aerials.

h. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a much faster deployment time compared to conventional full-size aerials.

i. the VIRTUAL GROUND MONOPOLE HF ANTENNA offers a much better E.M.I. compatibility with highly populated environments compared to conventional full-size aerials.

Applications:

a. SHORT WAVES FIXED & MOBILE RADIO STATION FOR CIVIL & MILITARY PURPOSES

b. STEALTH, FAST & TACTICAL DEPLOYMENT PURPOSES

c. SEARCH & RESCUE SERVICES

d. SHIP to SHIP & SHIP to SHORE MARINE COMMUNICATIONS

e. AIRCRAFT COMMUNICATIONS RANGE EXTENDING ANTENNA

f. DX-ing and metropolitan HAM RADIO STATIONS

g. ELEMENT in ARRAYS of AERIALS

h. RADIO-PHYSICS LABORATORIES

Price:
Euro 650,00 +V.A.T. and shipping costs.
For an useful currency converter click here

NB. Price DOES NOT INCLUDE the cost of the twinned coaxial line.

FOR INSTANCE, a 30 meter long twinned RG-213 coaxial transmission line complete with 4 PL-259 original Amphenol connectors and weather-resistant cable ties can be supplied at the cost of Euro 100,00 + Carriage.

RADIONDISTICS' products carry an unconditional lifetime guarantee.

This device is patented & Copyright © 2003-
of
FRANCESCO ERRANTE.

No reproduction, in whole or in part, without written permission
Material is governed by the Copyright, Designs and Patent Act
All rights reserved.