CA2032651A1 - Telephone subscriber line voltage change detection - Google Patents

Telephone subscriber line voltage change detection

Info

Publication number
CA2032651A1
CA2032651A1 CA2032651A CA2032651A CA2032651A1 CA 2032651 A1 CA2032651 A1 CA 2032651A1 CA 2032651 A CA2032651 A CA 2032651A CA 2032651 A CA2032651 A CA 2032651A CA 2032651 A1 CA2032651 A1 CA 2032651A1
Authority
CA
Canada
Prior art keywords
subscriber line
line voltage
telephone
change detection
tapping
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.)
Granted
Application number
CA2032651A
Other languages
French (fr)
Other versions
CA2032651C (en
Inventor
David Arnold Pepper
Robert James Miller
Richard Joseph Malyszka
Andre Jean Robert
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.)
Nortel Networks Ltd
Original Assignee
Northern Telecom 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 Northern Telecom Ltd filed Critical Northern Telecom Ltd
Priority to CA 2032651 priority Critical patent/CA2032651C/en
Priority to JP35234691A priority patent/JPH0541732A/en
Publication of CA2032651A1 publication Critical patent/CA2032651A1/en
Application granted granted Critical
Publication of CA2032651C publication Critical patent/CA2032651C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Telephonic Communication Services (AREA)
  • Monitoring And Testing Of Transmission In General (AREA)

Abstract

TELEPHONE SUBSCRIBER LINE VOLTAGE CHANGE DETECTION

Abstract of the Disclosure Changes in a telephone subscriber line voltage are detected in a telephone set by supplying a voltage dependent upon the subscriber line voltage to a potential divider having first, second, and third tapping points, the second tapping point being between the first and third tapping points, and comparing the voltages at the first and third tapping points with a smoothed version of the voltage at the second tapping point to produce pulses at respective terminals when the line voltage is falling or rising. An algorithm is described for responding to the pulses to distinguish changes in hook state of another telephone connected to the same subscriber line from interfering signals. The arrangement facilitates remote release from hold and privacy indication functions for the telephone set.
CA 2032651 1990-12-19 1990-12-19 Telephone subscriber line voltage change detection Expired - Fee Related CA2032651C (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CA 2032651 CA2032651C (en) 1990-12-19 1990-12-19 Telephone subscriber line voltage change detection
JP35234691A JPH0541732A (en) 1990-12-19 1991-12-13 Device and method of detecting voltage change of telephone subscriber line

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA 2032651 CA2032651C (en) 1990-12-19 1990-12-19 Telephone subscriber line voltage change detection

Publications (2)

Publication Number Publication Date
CA2032651A1 true CA2032651A1 (en) 1992-06-20
CA2032651C CA2032651C (en) 1995-02-14

Family

ID=4146692

Family Applications (1)

Application Number Title Priority Date Filing Date
CA 2032651 Expired - Fee Related CA2032651C (en) 1990-12-19 1990-12-19 Telephone subscriber line voltage change detection

Country Status (2)

Country Link
JP (1) JPH0541732A (en)
CA (1) CA2032651C (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6323021B2 (en) * 2014-01-20 2018-05-16 オムロン株式会社 Object detection sensor and game machine

Also Published As

Publication number Publication date
JPH0541732A (en) 1993-02-19
CA2032651C (en) 1995-02-14

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Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed