FR515292A - Improvements to semi-automatic telephone systems - Google Patents

Improvements to semi-automatic telephone systems

Info

Publication number
FR515292A
FR515292A FR515292A FR515292DA FR515292A FR 515292 A FR515292 A FR 515292A FR 515292 A FR515292 A FR 515292A FR 515292D A FR515292D A FR 515292DA FR 515292 A FR515292 A FR 515292A
Authority
FR
France
Prior art keywords
semi
telephone systems
automatic telephone
automatic
systems
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
FR515292A
Other languages
French (fr)
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.)
Compagnie Francaise Thomson Houston SA
Original Assignee
Compagnie Francaise Thomson Houston SA
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 Compagnie Francaise Thomson Houston SA filed Critical Compagnie Francaise Thomson Houston SA
Application granted granted Critical
Publication of FR515292A publication Critical patent/FR515292A/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)
  • Interface Circuits In Exchanges (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
FR515292A 1919-05-28 1920-05-08 Improvements to semi-automatic telephone systems Expired FR515292A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US300277A US1515951A (en) 1919-05-28 1919-05-28 Automatic telephone system

Publications (1)

Publication Number Publication Date
FR515292A true FR515292A (en) 1921-03-26

Family

ID=23158425

Family Applications (1)

Application Number Title Priority Date Filing Date
FR515292A Expired FR515292A (en) 1919-05-28 1920-05-08 Improvements to semi-automatic telephone systems

Country Status (4)

Country Link
US (1) US1515951A (en)
DE (1) DE400928C (en)
FR (1) FR515292A (en)
GB (1) GB143842A (en)

Also Published As

Publication number Publication date
US1515951A (en) 1924-11-18
GB143842A (en) 1921-04-28
DE400928C (en) 1924-08-27

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