GB1349975A - Telecommunication systms - Google Patents

Telecommunication systms

Info

Publication number
GB1349975A
GB1349975A GB1349975DA GB1349975A GB 1349975 A GB1349975 A GB 1349975A GB 1349975D A GB1349975D A GB 1349975DA GB 1349975 A GB1349975 A GB 1349975A
Authority
GB
United Kingdom
Prior art keywords
sent
signal
cause
cease
check
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
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB1349975A publication Critical patent/GB1349975A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/0016—Arrangements providing connection between exchanges

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

1349975 Automatic exchange equipment STANDARD TELEPHONES & CABLES Ltd 24 Feb 1972 [12 Aug 1971] 37982/71 Heading H4K A telephone system including two or more switching centres has a path selected from an originating (calling) end to a terminating (called) end and a lock-in backward signal is sent to cause the path to be set up so that a forward ring-command signal generated at the originating end can be sent to the terminating end to cause ringing current to be applied and to check the speech channel connection. The connection may be controlled by a digital computer and can be between switching centres or the subscribers terminals. When the called party answers a further signal may be sent to check the speech channel in the backward direction and to cause generation of the ring-command signal to cease which itself causes the answer signal to cease.
GB1349975D 1971-08-12 1971-08-12 Telecommunication systms Expired GB1349975A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3798271 1971-08-12

Publications (1)

Publication Number Publication Date
GB1349975A true GB1349975A (en) 1974-04-10

Family

ID=10400386

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1349975D Expired GB1349975A (en) 1971-08-12 1971-08-12 Telecommunication systms

Country Status (2)

Country Link
BE (1) BE787433A (en)
GB (1) GB1349975A (en)

Also Published As

Publication number Publication date
BE787433A (en) 1973-02-12

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Legal Events

Date Code Title Description
PS Patent sealed
435 Patent endorsed 'licences of right' on the date specified (sect. 35/1949)
PCNP Patent ceased through non-payment of renewal fee