GB986012A - Method of receiving voice-frequency code signals - Google Patents

Method of receiving voice-frequency code signals

Info

Publication number
GB986012A
GB986012A GB1719762A GB1719762A GB986012A GB 986012 A GB986012 A GB 986012A GB 1719762 A GB1719762 A GB 1719762A GB 1719762 A GB1719762 A GB 1719762A GB 986012 A GB986012 A GB 986012A
Authority
GB
United Kingdom
Prior art keywords
receivers
frequencies
code
respond
combinations
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
GB1719762A
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
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB986012A publication Critical patent/GB986012A/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
    • H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
    • H04Q1/453—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling in which m-out-of-n signalling frequencies are transmitted

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

986,012. Selective signalling. STANDARD TELEPHONES & CABLES Ltd. May 4, 1962 [May 5, 1961], No. 17197/62. Heading G4H. [Also in Division H4] An arrangement for receiving VF signals comprising one or several frequencies selected from a number of frequencies, e.g. for sending numerical information in a telephone system, employs a number of receivers each of which responds to a range of adjacent signalling frequencies. In the case of a 1-out-of-10 code the receivers E1- E6 Fig. 2, respond to the ranges S1-S5, S2-S6 and so on to S6-S19. This results in a simple contact tree, Fig. 3, for controlling the outgoing circuits. When a 2-out-of-6 code is used, the receivers E1- E5, Fig. 4, respond to adjacent pairs of frequencies, and the code combinations to be used are limited to those which produce different effects. Other codes considered are 2-out-of-4, 2-out-of-5 and 1-out-of- 4 plus 1-out-of-4. It is practicable in some cases to choose the combinations to be used in such a way that the failure of one frequency or the addition of an unwanted frequency may be recognized at the receivers.
GB1719762A 1961-05-05 1962-05-04 Method of receiving voice-frequency code signals Expired GB986012A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEST17776A DE1154838B (en) 1961-05-05 1961-05-05 Method for receiving tone-frequency code characters

Publications (1)

Publication Number Publication Date
GB986012A true GB986012A (en) 1965-03-17

Family

ID=7457599

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1719762A Expired GB986012A (en) 1961-05-05 1962-05-04 Method of receiving voice-frequency code signals

Country Status (2)

Country Link
DE (1) DE1154838B (en)
GB (1) GB986012A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3493934A (en) * 1967-01-06 1970-02-03 Ibm Tone decoder having plural reference tones

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL130386C (en) * 1958-06-20

Also Published As

Publication number Publication date
DE1154838B (en) 1963-09-26

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