GB1253498A - Electronic supervision circuit for telecommunication systems - Google Patents

Electronic supervision circuit for telecommunication systems

Info

Publication number
GB1253498A
GB1253498A GB1062870A GB1062870A GB1253498A GB 1253498 A GB1253498 A GB 1253498A GB 1062870 A GB1062870 A GB 1062870A GB 1062870 A GB1062870 A GB 1062870A GB 1253498 A GB1253498 A GB 1253498A
Authority
GB
United Kingdom
Prior art keywords
terminals
transistor
choke
march
hook
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
GB1062870A
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 GB1253498A publication Critical patent/GB1253498A/en
Expired legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q3/00Selecting arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Abstract

1,253,498. Automatic exchange systems. INTERNATIONAL STANDARD ELECTRIC CORP. 5 March, 1970 [7 March, 1969], No. 10628/70. Heading H4K. A circuit for supervising the state of a line circuit uses four transistors with two 1, 5 connected to the "a" ling through choke 11 and two 3, 6 connected to the "b" line through choke 14. A battery is connected to resistor 15 and to Zener diode 20. The output of the two circuits are connected to detector scanner terminals 7, 8 respectively. The transistor 3 is biased to become conductive or non-conductive dependent on the resistance of the subscriber loop. The transistor 1 is connected to conduct and remain conducting whenever the subscriber loop is closed. Thus signals (0, 0) and (1, 1) at terminals 7, 8 represent on hook and off hook conditions respectively. - An additional recall facility is obtained by operating switch 18 which inserts high resistance 18 in the loop thus turning off transistor 3 and provides signals (1, 0) at terminals 7, 8 of detector scanner. Spurious calling conditions caused by earth faults and short circuits are indicated as (0, 1) at terminals 7, 8.
GB1062870A 1969-03-07 1970-03-05 Electronic supervision circuit for telecommunication systems Expired GB1253498A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR6906404A FR2036239A5 (en) 1969-03-07 1969-03-07

Publications (1)

Publication Number Publication Date
GB1253498A true GB1253498A (en) 1971-11-17

Family

ID=9030281

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1062870A Expired GB1253498A (en) 1969-03-07 1970-03-05 Electronic supervision circuit for telecommunication systems

Country Status (4)

Country Link
DE (1) DE2009686A1 (en)
ES (1) ES377207A1 (en)
FR (1) FR2036239A5 (en)
GB (1) GB1253498A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2939009A1 (en) * 1979-09-26 1981-04-09 Siemens AG, 1000 Berlin und 8000 München CIRCUIT ARRANGEMENT FOR DETERMINING THE SWITCHING STATE OF A SUBSCRIBER CONNECTION LINE IN TELEPHONE SWITCHING SYSTEMS

Also Published As

Publication number Publication date
DE2009686A1 (en) 1970-09-24
ES377207A1 (en) 1972-06-01
FR2036239A5 (en) 1970-12-24

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