US1313860A

US1313860A - Electric-wave-relaying system

Info

Publication number: US1313860A
Authority: US
Publication date: 1919-08-19
Anticipated expiration: 1936-08-19

Description

J. H. HAMMOND, JR. ELECTRIC WAVE RELAYING SYSTEM. APPLICATION FILED JUNE I2. I912.

2 SHEETS-SHEET WITNESSES III/VENTOR iw M Jaw man/ms Patented Aug. 19, 1919.

J. H. HAMMOND, JR. ELECTRIC WAVE RELAYING SYSTEM.

APPLICATION FILED JUNE 12, 1912.

Patented Aug. 19, 1919.

2 SHEETSSHEET 2- INVENTOI? By Z M 4 2% ATTORNEYS WITNESSES "UNITED s'ra'rns PAT OFFICE.

JOHN HAYS HAMMOND, JR, 0F GLOUCESTER, MASSACHUSETTS.

ELECTRIC-WAVE-RELAYING SYSTEM.

Specification of Letters Patent.

Patented Aug. 19, 1919.

Application filed June 12. 1912. Serial No. 703.219.

To all whom it may concern:

Be it known that I, JOHN HAYS HAM- MOND, Jr., a citizen of the United States,

residing at Gloucester, in the State of Massachusetts, have invented certain new and useful Improvements in Electric-Wave- Relaying" Systems, of which the following is a specification.

My invention relates to systems for the relaying of electric wave signals, and relates more particularly to the automatic reception and transmission of radio telegraph and telephone messages at a relay station, and relates furthermore to methods and'apparatus for securing selectivity in such electric wave relaying systems.

.In the accompanying figures:

Figure 1 shows a transmittin station on my selective electric w-ave relaylng system,

Fig. 2 shows a relay station on my system.

Fig. 3 shows a receiving station on my system, which is out of range of the trans- I .When telephone messages are to be sent, the

mitting stationof Fig.1, but within range of the relay station of Fig. 2.

Fig. 4 shows a relay station on my system, in which part of the apparatus is of a modified form, and which has also apparatus forthe local amplification of the received signals.

In Fig. 1 an alternating current generator G, of a frequency preferably above the range of audibility, energizes the field coils F of a high-frequency alternator H. Alternator H is inductively coupled to the antenna A by means of the coils L and L Antenna A is in circuit with a condenser transmitter N M, and interrupter I and a key K, and is grounded at E. A resistance microphone T, in connection with the battery B and 'electro-magnet 1), controls the diaphragm M of the'condenser transmitter.

The high-frequency alternator H produces oscillations in the antenna A and the generator G produces amplitude variations at-a definite rate in these oscillations, andhence in the electric waves radiated from the antenna. The interrupter I has a defi- -nite rate, Within the limits of audibility, and

is operated in connection with the'key K.

when telegraph signals are to' be sent;

interrupter I and the key K are kept closed, and the sound waves at microphone transmitter T cause vari'ationsfin the current 4 through electromagnet D, which latter actuother magnetic substance, and the telephonic vibrations are impressed upon the antenna A by means of the variations in the capacity of the condenser transmitter M N, and hence upon the electric waves radiated therefrom.

In .Fig. 2 receiving apparatus and transmitting apparatus are connected to the same antennaA At the receiving side, antenna A is in circuit with the inductance coil L and the variable condcnserC, and is grounded at E The closed oscillatory cir- 'cuit L C is coupled to the open antenna circuit bymeans of the coils L and L, and both these circuits are in resonance with the high-frequency alternator H, of Fig. 1. By the action of rectifier R and coupling coils L and L, circuit L C supplies unidirectional current impulses to 'the circuit containing coil L condenser C elcctromagnet D and receiving telephone P, which circuit is in resonance with the alternatingcurrent generator G of Fig. 1. Telephone P will enable telephone messages originating at T in Fig. 1 to be heard at the relay station. Electromagnet D actuates the condenser transmitter M N, which is in the transmitting antenna circuit A L M N E An alternating current generator G which is of a frequency preferably above the limits of, audibility, energizes the field winding F of high-frequency alternator H The frequency of generators G and G and of alternators H and H should be different. Gr impresses periodic amplitude variations on the current of H H being audibility, due to the action of generator G and, in addition, vibrations are im-- pressed upon the antenna circult by means of the condenser transmitter M N which reproduces exactly the telephone messages, originating at transmitter T of Fig. 1, or

the telegraph signals originating at key K and interrupter I of Fig. '1. These relayed signals or messages arethus sent out with renewed power from the relay station.

In Fig. 3 the receiving antenna'A 1s in circuit with inductance coil L and con-' denser C and .is grounded at E It is inductively coupled to closed osclllatory c1 reuit LVC, and both these circults are m resonance with alternator H of Fig. 2. The circuit L C by means of rectifier R and coil L, supplies energy to the circuit L C P containing the coil L condenser C and receiving telephone P and being in res- 'onance with generator G of Fig. 2. All

- C, and both these circuits are in resonance with the wave frequency of the transmitting station. By means of the rectifier R and coupling coil L 'ciruit L C D which is in resonance with the periodic amplitude variations of the transmitted electric'waves,

is energized. Electromagnet D actuates the magnetic diaphragm S of the resistance microphone T T is in circuit with battery B and the electromagnets D D, D: D", D and D These electroma 'ets actuate, respectively, the magnetic diaphragms M Mfi-M M", M and M of a multiple condenser transmitter, which transmitter is in 'thetransmi'tting antenna circuit A L L M M M M M M E An alternating current generator G of afre uency preferably above the limits of audi ili-ty, energizes the field winding F of the high- V frequency alternator H :riodic amplitude variations upon the current G impresses peof H H being inductively connected with the transmitting antenna A by means of the coupling coils L and U. The electric waves radiated from the antenn aA have periodic amplitude variations of, a fre* quency above the limits of audibility, owin to the action of the generator stand, i addition, vibrations are impressedupon the antenna circuit, #by means of the multiple condenser transmitter M M M M M" M*,

which re roduces, with an amplified volume,

the telep one and telegraph messages. originating at the transmittingstation. These messages are thus sent out with increased power fromth'e relay station. This multiple condenser 'tragsmitter has already been fully described in another a plioationoi mine, (Serial No. 702,176, led June 7,

greater detail here.-

This multiple condenser transmitter canas the first-mentioned waves, and receiving.

1912-), and so need, not-be described) in also be used to produce an amplification of sounds 'or. other signals at the relaystation orelsewhere. As shown, it is inductively coupled, by means of the coil L, .with the circuit containing the coilL, rectifier R loud-speaking telephone and electromagnet D and the amplified currents induced in this latter circuit will produce amplified sounds at Q, or will operate through the electroma'gnet D and relay sWitch W to actuate local mechanisms U V.

Other means may be employed for reproducing amplitude variationsfor group frequencies in my electric waves, such as revolving', coils, high-frequency interrupters and the like, -shown and described in other applications of mine, other forms of microphones and othertransmitters may beused at my transmitting and my relay stations, and variousxother changes and modifications, within the ability of those skilled in the art,

may be made. in the particular apparatusshown and described herein, without departing from the spirit of my invention, rovided the means set forth in the follow-- mg claims be employed.

I claim as my invention 1. A system comprising a sending station adapted to emit electric waves having definite characteristics, a receivin station,

and a relaying station, interpose between the sending station and the receiving station, provlded with means for emltting waves of different definite characteristics and means for receiving variable wave characteristics produced at the sendingstation and impressing identical variations on the waves emitted from said relay station,

said receiving station being turned to the wave characteristics of the relay station;

2. A system for the relaying of wireless.

signals, which comprises a sending station emitting electric waves having a fixed characterlstlc and a variable characteristic, a recelvmg station, and a relay station provided and the same variable characteristic.

3. In a system for the relaying of wireless slgnals, a relay station comprising doubly selective receiving means, independent means for emitting waves having predetermined lengths andpredetermined amplitude variations and automatically actuated means controlled by said receiving ted waves.

with means for receiving and emitting .electric waves of different fixed characteristics means for impressing variations on theemit- 4. A method forv relaying radio mesa sages, which consists in transmitting waves having*fixed characteristics and avariable characteristic from a transmitting station, receivmg sald waves at a relay station, automatically emittin vWaves from said relay station having di erent fixed characteristics from and the same variable characteristic the last-mentioned waves-at a receiving station. v

5. In a system (for the relaying of radio messages, a relay station comprismg means for receiving electric vwaves having predetermined characteristics, independent means for emittin electric Waves havin different predetermined characteristics, an means actuated by the received waves for impressing variations on the emitted waves.

6. A relay station for radio telephony,

; comprising means for receiving electric waves having fixed characteristics and a variable characteristic, means for emitting waves having difi'erent fixed characteristics,

and automatic means for impressing the variable characteristic of the received waves upon the emitted waves. 7

7. A relay station for radio signals, comprising means for receiving tuned electric waves with periodic amplitude variations, means for amplifyin the received signals,

means for transmitting diiferently tuned electric waves with different periodic amplitude variations, means for impressing the amplified signals upon the last-mentioned waves, and means for receiving the signals locally .in an amplified form.

8. A relay station for radio telephony, comprising selective means for receiving electric Waves having telephonic variations, selective means for emitting electric waves, automatic means for amplifying the telephonic variations and impressing them upon the emitted waves, and means for amplifying the received telephone mes sages.

9. A method of relaying in radio telephony which consists in transmitting 'Waves having a plurality of characteristics, im-

' ,pressing telephonic variations upon said waves, receiving said waves at a relay station, automatically emitting waves from said relay station havin different characteristics from the first-mentioned Waves but the same telephonic variations, and receiving the lastmentioned waves at a receiving station.

10. The combination with transmission means including means for generating electrical oscillations of a predetermined frequency, means for simultaneously impress ing regular eriodic variations of a redetermined requei cyand irregular, undulations corresponding to sound waves upon said oscillations of a relay including receiving means comprising responsive means in resonance with said oscillations, responsive means controlled by said first mentioned responsive means and in resonance with said periodic variations, means for generating electrical oscillations of a predetermined frequency, means for. impressing regular periodic variations of a periodic variations, means for sponsive means and in resonance with said eneratin electrical oscillations of a re etermine frequency diflei'ent from said first mentioned frequency, means for impressing regular periodic variations of a predetermlnec'l frequency different from said second mentioned frequency upon said last mentioned oscillations, and means controlled by said second mentioned responsive means for impressing undulations corresponding to said sound waves upon said last mentioned oscillations.

12. The combination with transmission means including means for enerating electrical oscillations of a pre etermined frequency, means for simultaneously impress-f ing regular periodic amplitude variations of a predetermined frequency and irregular undulations corresponding to sound waves upon said oscillations of a relay including receiving means comprising. responsive means in resonance with said oscillations, responsive means controlled by said first mentioned responsive means and in resonance with said periodic variations, means for generating electrical oscillations of a predetermined frequency, means for impressing regular periodic amplitude variations of a predetermined. frequency upon said last mentioned oscillations, and means controlled by said second mentioned responsive means for impressing undulations corresponding to said sound waves upon said last mentioned oscillations.

'This specification si ed and witnessed this 22nd day of May, I D 1912.

JOHN HAYS HAMMOND, JR.-

Witnessesi MABEL J. COOPER, OLIVE B. Knee.