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Publication numberUS1744036 A
Publication typeGrant
Publication dateJan 21, 1930
Filing dateNov 6, 1925
Priority dateJan 17, 1924
Publication numberUS 1744036 A, US 1744036A, US-A-1744036, US1744036 A, US1744036A
InventorsEvenor Brard
Original AssigneeOndes Dirigees Sa Des
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Process for radiotelegraphic or radiotelephonic communication
US 1744036 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Jan. 21, 1930. E. BRARD 1,744,036


The present invention relates to improvements in the processes for radiotelegraphic or telephonic communications in which a primary station Whose emanations are received 3 by a secondary station, may, in turn, receive from the latter, being thus able to secure a junction, although there is no energy supply at the secondary station,

The primary station comprises a source of oscillations and an emitting circuit; the secondary has a receiving circuit with no local energy source, and in which is inserted a manipulating or modulating device (telephonic or telegraphic apparatus).

At the primary station, the receiving circuit is connected, directly or inductively, to the emitting circuit, and the ordinary amplifying devices are used. Of course, the communicating stations must be tuned; this tuning is obtained in the well-known means.

In the drawing is illustrated as an example a diagrammatic arrangement embodying the invention and giving the best results.

At the primary station, an aerial 1 is fed by the ordinary generating device comprising an audio-tube 2, plate battery 4, self-inductance 5, filament battery 12, tuning condenser 13 and variometer 10.

At the secondary station R, is provided an aerial 7 with tuning condenser 8, constituting a circuit tuned to the waves emitted by the primary station.

When the circuit E works as an emitting one, and assuming that the stations E and R are tuned, if one manipulates, by making a cut 9, in the circuit R, the effect of this manipulation will be received on the circuit E. Further, if a transformer 7--8, with am plifying device 9, is COIlDGC'EGCl'WllCh the emitu' ting circuit Q-3l513-612, the signals of the circuit R will be received the telephone 11, at the outlet of the amplifying device.

Moreover, these signals may be produced by a telephonic modulation as Well as a telegraphic one, according to whether a microphone or key is used.

Having described my lnventron, what I claim is 1. A system of radio communication comprising a main transmitting station, an oscillator tube and transmitting aerial therefor at the main station, means for adjusting the frequency of the oscillator, means for tuning the transmitting aerial, a secondary station Without energy source having an aerial arranged to be tuned to the frequency of the transmitting aerial of the main station, means wholly at the secondary station for modulating the electrical energy induced in its aerial according to a signal to be transmitted to the main station, and an amplifying receiver at the main station operatively connected with the oscillator tube and its transmitting aerial for receiving the modulations produced at the secondary station.

2. A system of radio communication comprising a main station, a secondary station, a tuned circuit at the secondary station without energy source, means for varying the electrical condition of said tuned circuit, and unitary means at the primary station for transmitting unmodulated radio waves to the tuned circuit at the secondary station and responsive to the variations in the electrical condition of said tuned circuit to render the same perceptible at the primary station.

3. A system of radio communication comprising an audion tube oscillator and circuit therefor having a plate-filament circuit and a grid-filament circuit, an antenna connected With the plate circuit and a radio receiving set connected with the grid circuit, a remote non-generating circuit arranged to receive waves radiated from said antenna, and means for modulating the Waves in said non gencrating circuit, said antenna and non-generating circuit being so related that the modulated Waves will in effect be transmitted to the said antenna, and said radio receiving set being arranged to respond to said modulations, substantially the entire energy of all of said Waves being derived from a common source.

4. The method of radio communication which consists in transmitting radio waves of a length above ten meters from a primary station to a resonant circuit without energy source at a secondary station, modulating said Waves in circuit at the secondary station with signal modulations, and transmitting the modulated Waves from the secondary station to the primary station Without additional energy.

5. The method of radio signaling which comprises generating radio frequency Wave energy at one station, transmitting the same to a second station, transforming the Wave energy received at the second station Without additional energy into current oscillations, modulating said current oscillations at the second station to produce modulated Wave energy, and receiving and demodulating the modulated Wave energy at a point remote from the second station.-

6. The method of radio signaling which comprises generating radio frequency Wave energy at one station, transmitting the same to a resonant circuit Without energy source at a second station, modulating the wave energy received thereat, receiving said modulated ave energy through space at a, point remote from said second station, and detecting the modulations from said received modulated Wave energy.

In testimony whereof I afiix my signature.


2 V i r 1,744,036

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2631280 *Aug 31, 1949Mar 10, 1953Rca CorpRemote-control system for radio receivers and the like
US2715725 *Jul 31, 1946Aug 16, 1955Jackson Frank HCircuit tester for electronic fuzes for munitions
US2927321 *Jan 26, 1956Mar 1, 1960Harris Donald BRadio transmission systems with modulatable passive responder
US3243801 *Nov 19, 1963Mar 29, 1966Lab For Electronics IncRadar system for identifying targets
US5523749 *Apr 3, 1992Jun 4, 1996Integrated Silicon Design Pty. Ltd.Identification system for simultaneously interrogated labels
US5793305 *Sep 29, 1995Aug 11, 1998Turner; Leigh HolbrookArticle sorting system
US7764177Jul 10, 2007Jul 27, 2010Allflex Usa, Inc.Inductively coupled extension antenna for a radio frequency identification reader
US8493185Oct 11, 2010Jul 23, 2013Aleis Pty LtdRadio frequency identification reader antenna having a dynamically adjustable Q-factor
US8581705Sep 4, 2009Nov 12, 2013Allflex Usa, Inc.Combination full-duplex and half-duplex electronic identification tag
US8811542Oct 12, 2010Aug 19, 2014Aleis Pty Ltd.HDX demodulator
U.S. Classification455/39, 455/121
International ClassificationH04B1/54
Cooperative ClassificationH04B1/54
European ClassificationH04B1/54