US2102903A - Loud-speaking and amplified microphone telephone exchange - Google Patents

Loud-speaking and amplified microphone telephone exchange Download PDF

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Publication number
US2102903A
US2102903A US759407A US75940734A US2102903A US 2102903 A US2102903 A US 2102903A US 759407 A US759407 A US 759407A US 75940734 A US75940734 A US 75940734A US 2102903 A US2102903 A US 2102903A
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Prior art keywords
circuit
relay
station
contact
calling
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Expired - Lifetime
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US759407A
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English (en)
Inventor
Leveque Emile
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Firm Le Telephone Prive Nat SA
FIRM LE TELEPHONE PRIVE NATIONAL SA
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Firm Le Telephone Prive Nat SA
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/20—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/001—Two-way communication systems between a limited number of parties

Definitions

  • Telephone systems which comprise a loud speaker and an amplified microphone permitting the subscribers to hear each other without taking the receiver to their ears and to speak di- 5 rectly into a microphone. It is also known to have relays in such systems which are controlled by the voice of the speaker,'said relays controlling certain circuitsof the system so that an acoustic coupling between the microphone and the loud 10 speaker of the same station cannot. take place.
  • These vocally controlled relays are generally of the differential type so that the direction of the paratus provided with a-micro-receiver. Indeed in these latter devices the danger of coupling does 25 not exist and, as a directing relay is absent, the sensitivity of the device is greatly increased. It may be said that the two subscribers feel each other.
  • the present invention aims to provide a system where the various difliculties arising between the attendants of the two stations equipped with loud speaker and amplified microphone are lessened 40 so much that the training which had to be acquired hitherto by long practice is automaticab ly regulated. For this reason such systems may be left in the hands of any body and their use will be more extensive than has been the .case
  • the system according to the present invention is constructed in a manner that each station is equipped so that it can take the initiative of a.
  • a certain number 0! stations having loud speakers and amplified microphones are grouped in an automatic central exchange .comprising as is usual intercommunicating groups by means of which the attendants may be connected automatically with each other.
  • the amplifying devices -.for the loud speakers as well as those for the microphones are connected to the central exchange where they belong tothese intercommunicating groups.
  • means may be provided for signalling from one station to the. other in spite of the automatic operation, in the same manner as if the two stations were connected without the intermediary of a central exchange.
  • Fig. 1 is a diagram showing two stations connected directly and provided with means for reciprocal intervention for directing the conversa- 40 tion.
  • two stations may be connected, said stations being provided with signalling systems similar to those of Fig. 2.
  • the stations I and II are each equipped with a loud speaker HP and a very sensitive microphone M. Besides they include a calling button a and. an intervention button i. At each station there is a buzzer R.
  • the outfit common to both stations comprises two fiers are of a known system and shall not be described.
  • the attendant at station I presses the button a and connects the buzzer with thepositive poleof a battery and with the amplifiers through the contacts A--l and A.3, said amplifiers transmitting the signal of the buzzer to the respective loud speaker.
  • This signal passes to the microphone of station I and the produced current acts on the relay C.
  • a weakening resistance of preventing the acoustic coupling between the microphone and speaker of the same station is inserted in each of the loud speaker currents; If the attendant at station I speaks, the associated relay C is energized to open contact C--
  • the stations I and II are likewise provided with a loud speaker HP, a microphone M, a calling button a, an intervention button 1 and a button d for ending the conversation.
  • Each station possesses, in addition, the signalling lamps V (green), B (white), R (red) or V1, B1, R1 respectively.
  • the two stations are shown directly connected but they could also be connected intermediately by an automatic device of known construction.
  • weakening circuits including resistances a are provided according to need by the control relays C, or C having each contacts I, 2 and 3 and a buzzer. R for calling. 1
  • the operator at station I wants to establish connection with 11 he presses the button a and the amplifiers AM1 and AMz are inserted into the circuit.
  • the buzzer R is operated, .but placed after the amplifier. There is no relay ,0 of the station I.
  • relay C is energized which at its contact 2 lights the green lamp V of the called station II and the red lamp R of the calling station I.
  • the operator at station I therefore has control of his call and the called operator is invited to make himself known. If this has been done the relay C will drop again and the red lamp of station I and the green lamp of station 11 will be extinguished. However the two white lamps B and B will be lit to prove that the connection has been established and that the line is free.
  • the relay C or 0' not only directs the conversation in one way or the other by cutting or reestablishing the circuit including the microphone of one of the operators and the loud speaker of the other operator, but also advises them of the direction of the conversation if the line is free.
  • FIG. 3 an intercommunicating group is represented between a central exchange and an autoswitch. This group is equipped with intervention and signalling devices described in the above.
  • the station I is supposed to be the caller and the station II the called. It is clear that these characters may be reversed.
  • the part III of the drawings is the central exchange- The connection is established as follows:
  • the caller switches his station to the central exchange by pressing the calling button.
  • the connection has been made which is marked .optically the attendant connects himself with the desired station by means of his finger dial.
  • the exchange comprises for each intercomrnunicating group symmetrically arranged an amplifier L1, L3, a rectifier valve La and L4 respectively, the transformers Trl, 'Ir2 and Tr3, Tr respectively.
  • the intercommunicatlng group comprises the locking relays C; C, control relays H, H, interfering relays IN, IN, stabilizing relays F, F, feeding relays D, D','D", a group relay 1, coupling relays UU, impulse relays Y, call relays 1313'; each station possesses a change over relay for the signalling lamps S, S and a line relay AA".
  • the contact A prepares the circuit of test
  • contact Y3 prepares the circuit of the group relay T--contact Y1 energizes the call finder CA.
  • Contact T1 cuts off the call finder-CA which stops on the line of the caller and energizes the relay 3.
  • Contact A cuts the short-circuit of the line III-IVcontact A lights the red lamp on the calling station, thus advising the attendant that the central exchange is ready to be dialed.
  • Contact J3 cuts the circuit of the relay T.
  • SUI prepares the setting to rest of they selector SU.
  • Contact SU cuts oil? a short-circuit of the relay U and prepares a short-circuit -of the winding I of relay Y.
  • the relay U being energized, the contacts U1, U3 separate the line III-IV from the relay Y and connect it to the transformer Tr 4, contact Us cuts the numbering circuit.
  • the contact U4 prepares a circuit of the relay NR; contact U5 prepares a holding circuit of the relays D+-D'-- D".
  • the contact Us holds the'relay B.
  • the relay Y drops.
  • the con tacts D1.and D4 prepare a circuit of the calling microphone.
  • the contacts D: and D5 prepare a circuit of the called microphone.
  • -The contact .Ds closes the circuit of the filament of the 4 triocles L1 L2 L3 L4D1 prepares the receiving circuit of the called-The contact D's prepares the circuit of the change over relay S of the signalling lamps of the station II--D"1 prepares the receiving circuit'of the called-The contact D": cuts the energizing circuit of the calling relay E and maintains the relays E--D--D"--D.
  • the contact D"4 prepares the circuit of the control relays H and H'Ds completes the circuit of the change over relay of the lamps S of the calling station-The contacts Si. and S2 light up the white lamp, and the red lamp extinguishes.
  • the contacts D; and D"; shall prevent that.
  • Circuit positivebuzzer -R0E2 workingprimary winding I of the transformer Tr lwinding 1 of the induction coilnegative.
  • Circuit negative common with the batteries (central and anodes), filament and space of filament and plate of the lamp L1-back contact of relay NR1-winding I of the transformer Tr 2 contact C'1--positive anodes.
  • the currents produced in the windings II and III of the transformer Tr 2 are transmitted to the called loud speaker by passing through the selector SU, arm d, e and the calling plate DA.
  • the oscillations received by the called loud speaker are retransmitted by acoustic coupling to the central exchange by the microphone at the called station.
  • microphonic currents are transmitted to the grid of the amplifying tube L3 by the intermediate of the winding III of the transformer Tr 3, they produce currents of the same nature, but amplified in the anode circuit of L3 in which is included the primary winding I of the transformer Tr 4.
  • the currents of the winding I of the transformer 4 are transmitted, one part to the calling loud speaker by the intermediate of the windings II and III of the Tr 4. The caller is thus advised that the called has been called.
  • the contact Ci cuts the anode circuit of the amplifying lamp L1.
  • the contact C'2 relieves the short-circuiting of a resistance RS placed in the signalling circuit of the called. Therefrom results the dropping of the heavy armature I of his relay S and the lighting of his green lamp by the working contact S: and back contact S'1The contact 0:
  • the contact C's short circuits the relay GC4 short-circuits the receiver line III-IV of the called.
  • the contact C's cuts the signalling circuit of the caller. His relay S drops and causes the extinguishing of his lamp and the lighting of his red lamp by the back contact S2.
  • the contact C's short circuits the relay C during the different commutations caused by the relay C.
  • the contact C'a short-circuits the weakening resistance RC placed between II and III of the transformer 4.
  • Circuit 'positive-D5 working-T3 back-U4 workingwinding of NR--negative.
  • the relay E controls again the calling circuit.
  • the relay NR reverses at its contacts NR1 and NR: the anode circuits of the triodes L1 and La and the oscillating current produced by the buzzer R0 and amplified by the triode L1 will be received this time by the intermediate of the transformer Tr 4 by the loud speaker of the caller.
  • station X himself known by the words here station X.
  • the contact C's short-circuits the relay G and the contact 0'4 short-circuits the receiver line III-IV of the called.
  • the contact C's closes again the signalling circuit of the caller which will cause the energizing of his relay S and will cause the lighting of the white lamp by the working contacts S1 and S2.
  • the contact C's short-circuits the weakening resistance RE placed between the windings II and III of the transformer Tr 4.
  • the white lamp at the two stations advises that the double connection (going and returning) has been established.
  • the eflect of the receiving is moderated by the resistances placed between 4 and 5 of the transformers Tr 2, Tr 4 and by the condensers shunted with the loud speakers by the working contacts S3. This efiect is regulated slightly above the limit of priming.
  • the cohtactGr blocks the relay G'by short circuiting the same.
  • the contact (is short-circuits the control relay H which is energized.
  • the contact H1 energizes the locking relay C and light armature I of the stabilizing relay ,F..
  • the locking relay being energized, the contact C1 cuts the anode circuit of La.
  • Contact Ca opens the circuit of the resistanceRS included into the signalling'circuit of the calling station. the result of which is to cause. the dropping of the heavy armature II of its relay S and to cause the lighting of itsgreen lamp by means of the working contact 8: and the back contact 81,
  • the contact C4 short-circuits the receiving line of the caller.
  • Contact Cs cuts the signalling circuit of the called station whereupon the relay called station) presses once his button in.
  • the contact Cc short-circuits the relay G during the process of commutation assured by the locking relay C.
  • the contact Cs'ShOI't-Oll'fllltfi the weakening resist-' ance RC connected between. the windings'II and IIIoi the transformerTrL v '
  • the contact I prepares the circuit of the control-winding oithe heavy armature stabilizing relay F. Y On this principle the communication may continue without limit. Each. time that one of the interlocutors stops to speak the communication becomes bilateral (white lamp at the two stations) and the initiative of the conversation may be taken up by one. or the other of the attendants.
  • the interfering relay IN being energized, the contact IN; cuts the circuit of the central relay H-The contact IN'g'cutsthe circuit of the relay G.
  • Contact IN'a cuts the retarded circuit of the 'relay H, 'so that the latter may drop rapidly.
  • the contact INs completes a, holding circuit of the relay IN.
  • the relay H being cut oh, its contact H1 opens the circuit of the locking relay C which drops.
  • the contact Cr completes the anode circuit of the amplifier L3.
  • Contact C4 opens the short-circuit of the loud speaker line of the caller.
  • the current impulse generated thereby energizes the relay G:
  • the contact G's opens theshort-circuit of the winding I of control relay H, the armature of which is consequently attracted.
  • the contact Hz energizes the locking relay C which, by means of its contact (2' shortlIoi'the.
  • S circuits the loud speaker line of the attendant at the called station.
  • the contact C'1 opens the anode circuit of the amplifier L1, so that microphone currents of the station I are not transmitted to the loud speaker circuit of the called station.
  • the caller loses his priority.
  • the contact H cuts out the relay IN which drops, its
  • the caller may, in his turn, interfere in the same way. This time it will be the relay IN which to his advantage will play the part which the relay IN has played to the advantage of the caled station.
  • the buttons in and in shall also be used each time when there is noise in the-room where the called interlocutor is staying.
  • the stabilizing relay F in thecase of the caller, or the relay F respectively for the calling station.
  • a telephone system comprising a plurality of stations, each including a transmitter and a loudspeaking receiver, a circuit including an amplifier connecting the transmitter at one station with the receiver at a second station, a second circuit ineluding an amplifier connecting the transmitter 'at the second station with the receiver at the first circuit will be opened to break the last-recited circuit, a manually-controlled interrupting switch at the station including the transmitter of the flrsti'ecited circuit, a circuit including said interrupting switch and shunted across the switch in saidfi-rst-recited circuit, a second-manually-controlled interrupting switch at the second station, and a. circuit including said second interrupting switch and shunted across the switch in said second circuit.
  • a telephone system comprising a plurality of stations, each including a transmitter and a loudspeaking receiver, a circuit including an amplifier connecting the transmitter at one station with the receiver at a second station, a second circuit ineluding an amplifier connecting the transmitter at the second station with the receiver at the first station, a relay, a relay-opened switch in each cir-.
  • the relay in one circuit controlling the switch in the other circuit, whereby, upon energizing the relay in one circuit, the switch in the other circuit will be opened to break the last-recited circuit, a circuit including a resistance and a switch shunted across each receiver, and means controlled by the relay in each of the receiver circuits upon energization of the respective relays for opening the switch to break the respective associated resistance containing circuit.
  • a telephone system comprising a plurality of stations, each including a transmitter and a loudspeaking receiver, a circuit including an amplifier connecting the transmitterat one station with the receiver at a second station, a second circuit including an, amplifier connecting the transmitter at the second station with the receiver at the first station, a relay, a relay-opened switch in each circuit, the relay in one circuit controlling the switch in the other circuit, whereby, upon energizing the relay in one circuit, the switch' in the other circuit will be opened to break'the last-recited circuit, a circuit including a resistance and a switch shunted across each receiver, means controlled by the relay in each of the receiver circuits upon energization of the respective relays for opening the switch to break the respective associated resistance containing circuit, a manually-controlled interrupting switch at the station including the transmitter of the first-recited circuit, a circuit including said interrupting switch and shunted across the switch in said first-recited circuit, a second manually-controlled interrupting switch at the second station, a circuit including said second interrupting switch and
  • a telephone system comprising a plurality of stations, each including a transmitter and a loudspeaking receiver, a circuit including an amplifier connecting the transmitter at one station with the receiver at a second station, a second circuit including an amplifier connecting the transmitter at the second station with the receiver at the first station, a relay, a relay-opened switch in each circuit, the relay in one circuit controlling the switch in the other circuit, whereby, upon energizing the relay in one circuit, the switch in the other circuit will be opened to break the lastrecited circuit, a pair of signal lights of the same color, one at each station, a circuit connecting said lights in parallel, a two-way switch associated with each relay, a circuit serially including said two-way switches for energizing said parallel light circuit when both two-way switches are unaffected by the relays, a light of a second color and a light of a third color at each station, a circuit connecting the light of the second color at one station with the light of the third color at the other station, and means including said twoway relay-actuated
  • a telephone system comprising a plurality of stations, each including a transmitter and a loudspeaking receiver, a circuit including an amplifier connecting the transmitter at one station with the receiver at a second station, a second circuit including an amplifier connecting the transmitter at the second station with the receiver at the first station, a relay, a relay-opened switch in each circuit, the relay in one circuit controlling the switch in the other circuit, whereby, upon energizing the relay in one circuit, the switch in the other circuit will be opened to break the lastrecited circuit, an interrupting switchat the station including the transmitter of the first-recited Y circuit, a circuit including said interrupting switch and shunted across the switch in said first-recited circuit, a second interrupting switch at the second station, a circuit including said second interrupt ing switch and shunted across the switch in said second circuit, a pair of signal lights of the same color, one at each station, a circuit connecting said lights in parallel, a two-way switch associated with each relay, a circuit serially including said two-way switches for energ
  • a telephone system comprising a plurality of stations, each including a transmitter, a loudspeaking receiver and a station calling dial, a central exchange common to said stations, a circuit at said exchange for transmitting from the calling station to the called station, a second circuit at the exchange for transmitting from the called to the calling station, means at the exchange operable upon transmission over one circuit for preventing transmission over the other circuit, a call finder at the exchange for connecting said circuits to the calling station, means at the calling station and at the exchange for actuating said call finder, a line selector for connecting said circuits to the called station, means actuated by the dial at the calling station for operating said line selector, interrupting means at the exchange for blocking transmission over either of said circuits, and means at said stations and connected through said call finder and line selector to said interrupting means for controlling the latter.
  • a telephone system comprising a plurality I of stations, each including a transmitter, a loudspeaking receiver and a station calling dial, a central exchange common to said stations, a circuit at said exchange for transmitting from the calling station to the called station, a second circuit at the exchange for transmitting from the called to the calling station, means at the exchange operable upon transmission over one circuit for preventing transmission over the other circuit, a call finder at the exchange for connecting said circuits to the calling station, means at thecalling station and at the exchange for actuating said call finder, a line selector for connecting said circuits to the called station, means actuated by the dial at the calling station for operating said line selector, signal lamps at each gizing alight of a second color at the calling station and a light of a third color at the called station, and means operable upon transmission from the called to the calling station for energizing a light of the second color at the called station and a light of the third color at the calling station.
  • a telephone system comprising a plurality of stations, each including a transmitter, a loud speaking receiver and a station calling dial, a central exchange common to said stations, a circuit at said exchange for transmitting from the calling station to the called station, a second circuit at the exchange for transmitting from the called to the calling station, means at the exchange operable upon transmission over one circuit for preventing transmission over the other circuit, a call finder at the exchange forconnecting said circuits to the calling station, means at the calling station and at the exchange for actuating said call finder, a line selector for connecting said circuits to the called station, means actuated by the dial at the calling station for operating said line selector, a calling contactor at each station, and stabilizing means at the exchangeunder control of the calling contactors blocked upon a pause for maintaining one of said transmission circuits the other circuit.
  • a telephone system comprising a plurality of stations, each including a transmitter, a loudspeaking receiver and a station calling. dial, a central exchange common to said stations, a circuit at said exchange for transmitting from the calling station to the called station, a second circuit at the exchange for transmitting from the called to the calling station, means at the exchange operable upon transmission over one circuit for preventing transmission over the other circuit, a call finder at the exchange for connecting said circuits to the calling station, means at the calling station and at the exchange for actuating said call finder, a line selector for connecting said circuits to the called station, means actuated by the dial at the calling station for operating said line selector, a refusing contactor at each station, and means at the exchange controlled by the refusing contactor for causing a refusing signal to be transmitted from the called station to the calling station.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
  • Devices For Supply Of Signal Current (AREA)
US759407A 1933-12-30 1934-12-27 Loud-speaking and amplified microphone telephone exchange Expired - Lifetime US2102903A (en)

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FR449609X 1933-12-30

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US2102903A true US2102903A (en) 1937-12-21

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US (1) US2102903A (enrdf_load_stackoverflow)
BE (1) BE407035A (enrdf_load_stackoverflow)
FR (2) FR789510A (enrdf_load_stackoverflow)
GB (1) GB449609A (enrdf_load_stackoverflow)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2424069A (en) * 1944-10-21 1947-07-15 Autophon Ag Voice operated switch for a duplex system
US2427983A (en) * 1944-03-09 1947-09-23 Autophon Ag Switching arrangement in duplex loud speaking systems
US2427850A (en) * 1945-03-17 1947-09-23 Rca Corp Switching method and system
US2451339A (en) * 1945-02-08 1948-10-12 Automatic Elect Lab Intercommunicating system
US2460475A (en) * 1942-12-04 1949-02-01 Autophon Ag Arrangement for changing over the speaking direction in loud-speaker duplex systems
US2470590A (en) * 1942-12-21 1949-05-17 Autophon Ag Remote-controlled automatic telephone for loud traffic
US2477275A (en) * 1944-01-15 1949-07-26 Firm Autophon Ag Voice-controlled two-way communication system
US2584790A (en) * 1945-12-18 1952-02-05 Rca Corp Switching circuit
US2694749A (en) * 1950-04-18 1954-11-16 Sepco 45 B D Sebastopol Communication system
US2819340A (en) * 1953-11-17 1958-01-07 Stanley S Brody Voice operated intercommunication system
US3023273A (en) * 1957-09-25 1962-02-27 Liberman Arie Communication system
US3439121A (en) * 1965-09-30 1969-04-15 Bell Telephone Labor Inc Multiple channel loud-speaking telephone

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE972766C (de) * 1941-12-14 1959-09-24 Normalzeit G M B H Sprechanlage mit mehreren Stationen und zentralem Verstaerker
DE1020371B (de) * 1952-10-15 1957-12-05 Svenska Relaefab Ab Wechselsprechanlage mit wahlweise durch die Sprechstroeme oder von Hand gesteuerter Umschaltung der Verkehrsrichtung
DE956693C (de) * 1953-03-19 1957-01-24 Telefunken Gmbh Schaltungsanordnung fuer Gegensprechanlagen
DE958935C (de) * 1954-02-08 1957-02-28 Telefunken Gmbh Schaltungsanordnung fuer sprachgesteuerte Echo- und Rueckkopplungssperren in Gegensprechanlagen mit Lautsprecherbetrieb
DE1019706B (de) * 1954-12-14 1957-11-21 Svenska Relaefab Ab Wechselsprechanlage mit wahlweise durch die Sprechstroeme oder von Hand gesteuerter Umschaltung der UEbertragungsrichtung

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2460475A (en) * 1942-12-04 1949-02-01 Autophon Ag Arrangement for changing over the speaking direction in loud-speaker duplex systems
US2470590A (en) * 1942-12-21 1949-05-17 Autophon Ag Remote-controlled automatic telephone for loud traffic
US2477275A (en) * 1944-01-15 1949-07-26 Firm Autophon Ag Voice-controlled two-way communication system
US2427983A (en) * 1944-03-09 1947-09-23 Autophon Ag Switching arrangement in duplex loud speaking systems
US2424069A (en) * 1944-10-21 1947-07-15 Autophon Ag Voice operated switch for a duplex system
US2451339A (en) * 1945-02-08 1948-10-12 Automatic Elect Lab Intercommunicating system
US2427850A (en) * 1945-03-17 1947-09-23 Rca Corp Switching method and system
US2584790A (en) * 1945-12-18 1952-02-05 Rca Corp Switching circuit
US2694749A (en) * 1950-04-18 1954-11-16 Sepco 45 B D Sebastopol Communication system
US2819340A (en) * 1953-11-17 1958-01-07 Stanley S Brody Voice operated intercommunication system
US3023273A (en) * 1957-09-25 1962-02-27 Liberman Arie Communication system
US3439121A (en) * 1965-09-30 1969-04-15 Bell Telephone Labor Inc Multiple channel loud-speaking telephone

Also Published As

Publication number Publication date
BE407035A (enrdf_load_stackoverflow) 1935-01-30
FR46765E (fr) 1936-09-11
FR789510A (fr) 1935-10-30
GB449609A (en) 1936-06-24

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JPS5924595B2 (ja) 局線保留方式