CA1003982A - Multifrequency dialing signal receiver for push-button type telephone systems - Google Patents

Multifrequency dialing signal receiver for push-button type telephone systems

Info

Publication number
CA1003982A
CA1003982A CA194,158A CA194158A CA1003982A CA 1003982 A CA1003982 A CA 1003982A CA 194158 A CA194158 A CA 194158A CA 1003982 A CA1003982 A CA 1003982A
Authority
CA
Canada
Prior art keywords
push
signal receiver
button type
telephone systems
type telephone
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
CA194,158A
Other languages
English (en)
Other versions
CA194158S (en
Inventor
Kunihiko Niwa
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.)
NEC Corp
Original Assignee
Nippon Electric Co Ltd
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 Nippon Electric Co Ltd filed Critical Nippon Electric Co Ltd
Application granted granted Critical
Publication of CA1003982A publication Critical patent/CA1003982A/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
    • H04Q1/457—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
  • Measuring Frequencies, Analyzing Spectra (AREA)
  • Electromechanical Clocks (AREA)
CA194,158A 1973-03-06 1974-03-05 Multifrequency dialing signal receiver for push-button type telephone systems Expired CA1003982A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2671073A JPS5733758B2 (de) 1973-03-06 1973-03-06

Publications (1)

Publication Number Publication Date
CA1003982A true CA1003982A (en) 1977-01-18

Family

ID=12200912

Family Applications (1)

Application Number Title Priority Date Filing Date
CA194,158A Expired CA1003982A (en) 1973-03-06 1974-03-05 Multifrequency dialing signal receiver for push-button type telephone systems

Country Status (5)

Country Link
US (1) US3917912A (de)
JP (1) JPS5733758B2 (de)
CA (1) CA1003982A (de)
DE (1) DE2410748C3 (de)
GB (1) GB1458891A (de)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3993875A (en) * 1975-05-23 1976-11-23 Houston Natural Gas Corporation Tone receiver
US4055730A (en) * 1975-05-29 1977-10-25 Comex Systems, Inc. Circuit for detecting dial pulses
US4009353A (en) * 1975-06-23 1977-02-22 International Business Machines Corporation Analog signal detection
US4045620A (en) * 1976-05-10 1977-08-30 Conrac Corporation Digital tone detector
JPS53149076A (en) * 1977-06-01 1978-12-26 Sony Corp Digital frequency detecting circuit
US4158110A (en) * 1977-08-25 1979-06-12 Tone Commander Systems, Inc. Tone selective key telephone intercom system including digital tone detector
US5905755A (en) * 1996-07-17 1999-05-18 Northern Telecom Limited Method and circuit for data regeneration of a data stream
TWI653833B (zh) * 2018-03-30 2019-03-11 和碩聯合科技股份有限公司 頻率測量系統及其測量方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3790720A (en) * 1972-10-27 1974-02-05 Northern Electric Co Digital decoder for multiple frequency telephone signalling

Also Published As

Publication number Publication date
DE2410748C3 (de) 1980-07-03
US3917912A (en) 1975-11-04
GB1458891A (en) 1976-12-15
AU6629574A (en) 1975-09-11
DE2410748A1 (de) 1974-09-19
JPS49115602A (de) 1974-11-05
DE2410748B2 (de) 1979-10-11
JPS5733758B2 (de) 1982-07-19

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