GB253575A - Improvements in automatic or semi-automatic telephone systems - Google Patents

Improvements in automatic or semi-automatic telephone systems

Info

Publication number
GB253575A
GB253575A GB674125A GB674125A GB253575A GB 253575 A GB253575 A GB 253575A GB 674125 A GB674125 A GB 674125A GB 674125 A GB674125 A GB 674125A GB 253575 A GB253575 A GB 253575A
Authority
GB
United Kingdom
Prior art keywords
test
automatic
contact
semi
marked
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
GB674125A
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.)
WESTERN ELECTRIC CO Ltd
AT&T Corp
Original Assignee
WESTERN ELECTRIC CO Ltd
Western Electric Co Inc
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 WESTERN ELECTRIC CO Ltd, Western Electric Co Inc filed Critical WESTERN ELECTRIC CO Ltd
Priority to GB674125A priority Critical patent/GB253575A/en
Publication of GB253575A publication Critical patent/GB253575A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker

Landscapes

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

Abstract

253,575. Standard Telephones & Cables, Ltd., (formerly Western Electric Co., Ltd.), and Lowry, L. P. March 12, 1925. Drawings to Specification. Semi-automatic exchange systems.-In a system in which an outlet relay group temporarily associated with an operator's keyboard is provided with a finder switch which hunts for an assigned trunk, the test contact of the latter being marked by the removal of earth, the test wiper of the finder is of the bridging type so that the switching relay which is short-circuited over earthed contacts during hunting shall not operate prematurely during the passage from one set of contacts to another. A relay in the trunk circuit which is to be operated by earth sent back over the test terminal from the outlet relay group is made slow to energize so as not to be operated prematurely when the test wiper bridges the marked test contact and a previous earthed contact. The invention is described with reference to apparatus which forms a part of the complete system described in Specification 254,183. Specifications 253,574 and 255,130 also are referred to.
GB674125A 1925-03-12 1925-03-12 Improvements in automatic or semi-automatic telephone systems Expired GB253575A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB674125A GB253575A (en) 1925-03-12 1925-03-12 Improvements in automatic or semi-automatic telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB674125A GB253575A (en) 1925-03-12 1925-03-12 Improvements in automatic or semi-automatic telephone systems

Publications (1)

Publication Number Publication Date
GB253575A true GB253575A (en) 1926-06-14

Family

ID=9819922

Family Applications (1)

Application Number Title Priority Date Filing Date
GB674125A Expired GB253575A (en) 1925-03-12 1925-03-12 Improvements in automatic or semi-automatic telephone systems

Country Status (1)

Country Link
GB (1) GB253575A (en)

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