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GB294217A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB294217A
GB294217A GB21085/28A GB2108528A GB294217A GB 294217 A GB294217 A GB 294217A GB 21085/28 A GB21085/28 A GB 21085/28A GB 2108528 A GB2108528 A GB 2108528A GB 294217 A GB294217 A GB 294217A
Authority
GB
United Kingdom
Prior art keywords
connector
calls
call
ground
preferred
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
GB21085/28A
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.)
Associated Telephone and Telegraph Co
Original Assignee
Associated Telephone and Telegraph Co
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 Associated Telephone and Telegraph Co filed Critical Associated Telephone and Telegraph Co
Publication of GB294217A publication Critical patent/GB294217A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Meter Arrangements (AREA)

Abstract

294,217. Associated Telephone & Telegraph Co., (Assignees of Wicks, J.). March 17, 1927, [Convention date]. Divided on 287,153. Drawings to Specification. Automatic and semi-automatic exchange systems.-In a, system in which established calls may be broken down in favour of toll calls or calls from another exchange in the area, a connector for use with local or preferred calls guards a preferred call by direct ground on the test multiple and a local call by ground through a low resistance relay which is short-circuited to release the connector when a connector proffers a preferred call to the called party. The circuit changes in a connector whereby it is adapted to operate for a preferred call are initiated, by a differential relay which is connected across the speaking wires and is unbalanced by the temporary application of ground to one of the wires by a toll operator or a repeater. The system described is identical with that described in Specification 287,153.
GB21085/28A 1927-03-17 1928-01-11 Improvements in or relating to telephone systems Expired GB294217A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US294217XA 1927-03-17 1927-03-17

Publications (1)

Publication Number Publication Date
GB294217A true GB294217A (en) 1929-04-11

Family

ID=21848935

Family Applications (1)

Application Number Title Priority Date Filing Date
GB21085/28A Expired GB294217A (en) 1927-03-17 1928-01-11 Improvements in or relating to telephone systems

Country Status (1)

Country Link
GB (1) GB294217A (en)

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