GB980785A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB980785A
GB980785A GB3777562A GB3777562A GB980785A GB 980785 A GB980785 A GB 980785A GB 3777562 A GB3777562 A GB 3777562A GB 3777562 A GB3777562 A GB 3777562A GB 980785 A GB980785 A GB 980785A
Authority
GB
United Kingdom
Prior art keywords
dialling
frequency
tone
receiver
exchange
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
GB3777562A
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.)
General Electric Co PLC
Original Assignee
General Electric Co 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
Application filed by General Electric Co PLC filed Critical General Electric Co PLC
Priority to GB3777562A priority Critical patent/GB980785A/en
Publication of GB980785A publication Critical patent/GB980785A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/446—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency
    • H04Q1/4465—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency the same frequency being used for all signalling information, e.g. A.C. nr.9 system

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

980,785. Automatic exchange systems. GENERAL ELECTRIC CO. Ltd., and H. B. TAYLOR. Oct. 23, 1963 [Oct. 5, 1962], No. 37775/62. Drawings to Specification. Heading H4K. An exchange which is provided with a VF receiver including a guard circuit for responding to VF dialling signals from a calling exchange has means for sending dialling tone of the same frequency as the dialling frequency to tell the caller to resume dialling, and in order to prevent operation of the VF receiver such tone comprises bursts of oscillatory current of shorter duration than the response time of the receiver. A frequency of 2280 cycles per second may be employed and the bursts of dialling tone may comprise two cycles of this frequency recurring 50 times per second. Busy tone may be similarly constituted. The calling and called exchanges may be connected by a cable or radio link which provides a number of 80 and return channels in frequency-division multiplex.
GB3777562A 1962-10-05 1962-10-05 Improvements in or relating to telephone systems Expired GB980785A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB3777562A GB980785A (en) 1962-10-05 1962-10-05 Improvements in or relating to telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3777562A GB980785A (en) 1962-10-05 1962-10-05 Improvements in or relating to telephone systems

Publications (1)

Publication Number Publication Date
GB980785A true GB980785A (en) 1965-01-20

Family

ID=10398925

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3777562A Expired GB980785A (en) 1962-10-05 1962-10-05 Improvements in or relating to telephone systems

Country Status (1)

Country Link
GB (1) GB980785A (en)

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