FR724352A - Improvements to telephone systems - Google Patents

Improvements to telephone systems

Info

Publication number
FR724352A
FR724352A FR724352DA FR724352A FR 724352 A FR724352 A FR 724352A FR 724352D A FR724352D A FR 724352DA FR 724352 A FR724352 A FR 724352A
Authority
FR
France
Prior art keywords
telephone systems
telephone
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
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.)
Associated Telegraph & Telepho
Original Assignee
Associated Telegraph & Telepho
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 Telegraph & Telepho filed Critical Associated Telegraph & Telepho
Application granted granted Critical
Publication of FR724352A publication Critical patent/FR724352A/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)
FR724352D 1931-05-07 1931-09-08 Improvements to telephone systems Expired FR724352A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US379671XA 1931-05-07 1931-05-07

Publications (1)

Publication Number Publication Date
FR724352A true FR724352A (en) 1932-04-26

Family

ID=21897335

Family Applications (1)

Application Number Title Priority Date Filing Date
FR724352D Expired FR724352A (en) 1931-05-07 1931-09-08 Improvements to telephone systems

Country Status (2)

Country Link
FR (1) FR724352A (en)
GB (1) GB379671A (en)

Also Published As

Publication number Publication date
GB379671A (en) 1932-08-29

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