GB1511767A - Telephone subscriber line monitoring - Google Patents

Telephone subscriber line monitoring

Info

Publication number
GB1511767A
GB1511767A GB4332276A GB4332276A GB1511767A GB 1511767 A GB1511767 A GB 1511767A GB 4332276 A GB4332276 A GB 4332276A GB 4332276 A GB4332276 A GB 4332276A GB 1511767 A GB1511767 A GB 1511767A
Authority
GB
United Kingdom
Prior art keywords
ringing
loop
condition
detector
closed
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
GB4332276A
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.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
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 International Standard Electric Corp filed Critical International Standard Electric Corp
Publication of GB1511767A publication Critical patent/GB1511767A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • H04M19/026—Arrangements for interrupting the ringing current
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/2272—Subscriber line supervision circuits, e.g. call detection circuits

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Abstract

1511767 Automatic exchange systems INTERNATIONAL STANDARD ELECTRIC CORP 19 Oct 1976 [25 Oct 1975] 43322/76 Heading H4K A circuit arrangement for monitoring the operating condition of a telephone subscriber line a, b, for connecting ringing current, through a generator G and for ring tripping, through ringing relay R and its command circuit is not provided with a separate detector for detecting the closed-loop condition during ringing. A detector I1 detects the closed-loop condition and a detector I2 in cooperation with I1 detects the depression of a grounding button; the output of both detectors are connected to a central control unit ST and the output of detector I1 is also connected to the control circuit of the ringing relay R, to suppress a ringing command when a closed loop condition is detected. The inputs to detectors I1 and I2 are connected to the line a, b as shown. Operation: Quiescent condition.-No supply current flows and the outputs of detectors I1, I2 are in the OFF state. Close-loop condition.-Removal of the handset causes supply current to flow in the subscribers loop; outputs of detectors I1, I2 in the ON state. Depressed - grounding - button - condition.- Operation of the grounding button causes current to flow in wire a through resistor W1 and resistor W1<SP>1</SP> is short circuited. The output of detector I2 is in its OFF state. The central control unit ST determines from the previous state of I1 whether the button was operated from a loop closed or loop open condition. Ringing condition.-Relay R is operated by control unit ST through h; ringing current flows from generator 6, via line and capacitor Cl to ground and supply U. Dl serves to divert positive peaks of ringing current. D2 is off and the outputs of I1, I2 are in the OFF state; hence Zener diode Z is cut off. Closed-loop condition during ringing.-When the subscriber lifts his handset a direct current flows in the loop superimposed on the alternating current. Diode D2 conducts to enable I1 whose output renders zener Z conductive so that transistor T is turned OFF thereby releasing relay R. While rl, r2 are switching back capacitor C maintains I1 enabled. Control unit ST responds to remove the signal on h.
GB4332276A 1975-10-25 1976-10-19 Telephone subscriber line monitoring Expired GB1511767A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19752547880 DE2547880C2 (en) 1975-10-25 1975-10-25 Circuit arrangement for recognizing the operating states of a subscriber line and for connecting and disabling calls in telephone exchanges

Publications (1)

Publication Number Publication Date
GB1511767A true GB1511767A (en) 1978-05-24

Family

ID=5960111

Family Applications (1)

Application Number Title Priority Date Filing Date
GB4332276A Expired GB1511767A (en) 1975-10-25 1976-10-19 Telephone subscriber line monitoring

Country Status (5)

Country Link
BE (1) BE847522R (en)
CH (1) CH599734A5 (en)
DE (1) DE2547880C2 (en)
FR (1) FR2329126A1 (en)
GB (1) GB1511767A (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2911584C2 (en) * 1979-03-23 1981-06-11 Siemens AG, 1000 Berlin und 8000 München Subscriber connection circuit with earth button actuation indication, high-resistance switchable supply and device for generating call signals
DE2911517C2 (en) * 1979-03-23 1981-07-09 Siemens AG, 1000 Berlin und 8000 München Subscriber connection circuit with earth button and insulation fault indication
NL7904429A (en) * 1979-06-06 1980-12-09 Philips Nv FLOW DETECTION DEVICE FOR AN AUTOMATIC TELEPHONE CONTROL PANEL.
DE3036686C2 (en) * 1980-09-29 1983-12-01 Siemens AG, 1000 Berlin und 8000 München Subscriber line circuit
DE3036657C2 (en) * 1980-09-29 1985-09-05 Siemens AG, 1000 Berlin und 8000 München Subscriber connection circuit for coin-operated telephones with switching means for determining the individual operating states to be monitored
DE3141375A1 (en) * 1981-10-17 1983-06-30 Felten & Guilleaume Fernmeldeanlagen GmbH, 8500 Nürnberg METHOD AND CIRCUIT ARRANGEMENT FOR DETECTING LOOP CURRENT CRITERIA IN A TELECOMMUNICATION SYSTEM
DE4003160C2 (en) * 1990-02-03 1995-07-13 Sel Alcatel Ag Circuit arrangement for call disconnection in the subscriber circuit of a telephone device
DE4019365A1 (en) * 1990-06-18 1991-12-19 Philips Patentverwaltung CIRCUIT ARRANGEMENT FOR A SUBSCRIBER DEVICE

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE629064A (en) * 1962-03-01
DE1919585C3 (en) * 1969-04-17 1974-06-06 Standard Elektrik Lorenz Ag, 7000 Stuttgart Circuit arrangement for calling subscriber stations equipped with ringer receivers in telecommunication systems, in particular telephone switching systems
DE2230040C3 (en) * 1972-06-20 1978-10-05 Siemens Ag, 1000 Berlin Und 8000 Muenchen Circuit arrangement for ringing current control in automatic telephone exchange systems
FR2193529A5 (en) * 1972-07-20 1974-02-15 Jeumont Schneider

Also Published As

Publication number Publication date
DE2547880C2 (en) 1981-09-24
FR2329126A1 (en) 1977-05-20
DE2547880A1 (en) 1977-05-05
BE847522R (en) 1977-04-22
CH599734A5 (en) 1978-05-31
FR2329126B1 (en) 1982-09-24

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Legal Events

Date Code Title Description
PS Patent sealed
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee