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GB879174A - Improvements in or relating to arrangements for determining the free or busy state of a line in a telecommunication system - Google Patents

Improvements in or relating to arrangements for determining the free or busy state of a line in a telecommunication system

Info

Publication number
GB879174A
GB879174A GB3121658A GB3121658A GB879174A GB 879174 A GB879174 A GB 879174A GB 3121658 A GB3121658 A GB 3121658A GB 3121658 A GB3121658 A GB 3121658A GB 879174 A GB879174 A GB 879174A
Authority
GB
United Kingdom
Prior art keywords
line
source
transistor
resistor
link
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
GB3121658A
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.)
Siemens and Halske AG
Siemens Corp
Original Assignee
Siemens and Halske AG
Siemens 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 Siemens and Halske AG, Siemens Corp filed Critical Siemens and Halske AG
Publication of GB879174A publication Critical patent/GB879174A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/0008—Selecting arrangements using relay selectors in the switching stages
    • H04Q3/0012—Selecting arrangements using relay selectors in the switching stages in which the relays are arranged in a matrix configuration
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Landscapes

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

Abstract

879,174. Automatic exchange systems. SIEMENS & HALSKE A.G. Sept. 30, 1958 [Sept. 30, 1957; Feb. 5, 1958], No. 31216/58. Class 40 (4). Supervisory current flowing in a line is detected by a transistor connected across a resistor in the line. The arrangement enables current differences to be detected independently of voltage differences on the supervisory line. As shown in Fig. 1 links between the row wires of relay matrices F1, F2 have resistors R1 across which the emitter and base of a transistor T are connected. The collector circuit of T comprises a voltage limiter R2, R3, G1 connected to voltage sources U1, U2. With the link idle and no current flowing T is cut off and terminal a has the potential of source U2. When the link is busy T conducts in response to current in R1 and enables G1 to conduct so that terminal a rises to the potential of source U1. A single link or a group of links may be artificially busied by providing a relay which disconnects the source U2 and replaces it with source U1. The resistor R1 may be constituted by the holding coil of a cross-bar switch such as the dry reed switch described in Specification 797,913. When in shunt across a holding coil the transistor should be in series with a limiting resistor.
GB3121658A 1957-09-30 1958-09-30 Improvements in or relating to arrangements for determining the free or busy state of a line in a telecommunication system Expired GB879174A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DES55387A DE1060446B (en) 1957-09-30 1957-09-30 Device for checking a line for its current occupancy status
DES56835A DE1084770B (en) 1957-09-30 1958-02-05 Device for checking a line for its current occupancy status

Publications (1)

Publication Number Publication Date
GB879174A true GB879174A (en) 1961-10-04

Family

ID=25995442

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3121658A Expired GB879174A (en) 1957-09-30 1958-09-30 Improvements in or relating to arrangements for determining the free or busy state of a line in a telecommunication system

Country Status (4)

Country Link
CH (1) CH368210A (en)
DE (2) DE1060446B (en)
GB (1) GB879174A (en)
NL (2) NL111529C (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL256763A (en) * 1959-10-16
DE1227500B (en) * 1961-02-04 1966-10-27 Standard Elektrik Lorenz Ag Method and circuit arrangement for determining the operating status of subscriber connections in telecommunications systems

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL196024A (en) * 1955-03-28
BE555481A (en) 1956-04-13

Also Published As

Publication number Publication date
DE1060446B (en) 1959-07-02
CH368210A (en) 1963-03-31
NL111529C (en)
NL231776A (en)
DE1084770B (en) 1960-07-07

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