GB957456A - Circuit arrangement for a key-controlled intercommunication system of the type in which each substation set is provided with a facility for calling any other station - Google Patents

Circuit arrangement for a key-controlled intercommunication system of the type in which each substation set is provided with a facility for calling any other station

Info

Publication number
GB957456A
GB957456A GB3524861A GB3524861A GB957456A GB 957456 A GB957456 A GB 957456A GB 3524861 A GB3524861 A GB 3524861A GB 3524861 A GB3524861 A GB 3524861A GB 957456 A GB957456 A GB 957456A
Authority
GB
United Kingdom
Prior art keywords
station
calling
line
key
stations
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB3524861A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AT674460A external-priority patent/AT221603B/en
Priority claimed from DEST16987A external-priority patent/DE1136745B/en
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB957456A publication Critical patent/GB957456A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
    • H04M19/04—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone the ringing-current being generated at the substations
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/04—Arrangements for interconnection not involving centralised switching involving a separate line for each pair of parties

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)

Abstract

957,456. Intercommunication systems. STANDARD TELEPHONES & CABLES Ltd. Sept. 29, 1961 [Oct. 8, 1960], No. 35248/61. Addition to 955,569. Heading H4K. In the normal condition of a station all incoming lines 1a, 1b to 5a, 5b from the other stations are interconnected via individual linekey contacts LT1II-LT5II and LT1IVLT5IV and rectifiers Glr1-Glr5, and are applied via further line-key contacts LT1ILT5I and LT1III-LT5III and press-to-talk button contacts SpTII and SpTIII to the transducer SW of the station, so that upon actuation of one line key only the line to the selected station remains connected while the other lines are disconnected and the supply battery UB of the calling station is applied via a resistor Wi1 to the line to the selected station. If the selected station is idle the corresponding rectifier there is rendered conductive and a voltage drop appears across resistor Wi1 at the calling station, causing a tone generator RG to apply a calling signal to the transducers SW at both stations. The tone generator RB is disconnected by contact SpTI when the speech button is operated. In a modification, Fig. 2 (not shown), the tone generator RG is connected to resistor Wi1 through a capacitor so that it oscillates for only a short time after a station has been called. Also in this modification the stations are interconnected by individual single wires and a common wire, cross-talk being largely eliminated by the use of an additional transformer at each station to increase its resistance.
GB3524861A 1960-09-02 1961-09-29 Circuit arrangement for a key-controlled intercommunication system of the type in which each substation set is provided with a facility for calling any other station Expired GB957456A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT674460A AT221603B (en) 1960-09-02 1960-09-02 Circuit arrangement for a transmission system for sound events
DEST16987A DE1136745B (en) 1960-10-08 1960-10-08 Circuit arrangement for a button-controlled intercom system of the type of traffic íÀJede mit JedemíÂ

Publications (1)

Publication Number Publication Date
GB957456A true GB957456A (en) 1964-05-06

Family

ID=25603287

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3524861A Expired GB957456A (en) 1960-09-02 1961-09-29 Circuit arrangement for a key-controlled intercommunication system of the type in which each substation set is provided with a facility for calling any other station

Country Status (1)

Country Link
GB (1) GB957456A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110386524A (en) * 2019-08-16 2019-10-29 钱良楚 Generally applicable arrival gong

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110386524A (en) * 2019-08-16 2019-10-29 钱良楚 Generally applicable arrival gong
CN110386524B (en) * 2019-08-16 2024-05-10 钱良楚 Universal arrival clock

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