FR540090A - Improvements to telephone networks - Google Patents

Improvements to telephone networks

Info

Publication number
FR540090A
FR540090A FR540090DA FR540090A FR 540090 A FR540090 A FR 540090A FR 540090D A FR540090D A FR 540090DA FR 540090 A FR540090 A FR 540090A
Authority
FR
France
Prior art keywords
telephone networks
telephone
networks
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)
Inventor
Ruber Christopher Mil Hastings
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 filed Critical
Application granted granted Critical
Publication of FR540090A publication Critical patent/FR540090A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
FR540090D 1921-08-17 1921-08-31 Improvements to telephone networks Expired FR540090A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB21848/21A GB193074A (en) 1921-08-17 1921-08-17 Improvements in telephone systems
FR540090T 1921-08-31

Publications (1)

Publication Number Publication Date
FR540090A true FR540090A (en) 1922-07-05

Family

ID=10169821

Family Applications (1)

Application Number Title Priority Date Filing Date
FR540090D Expired FR540090A (en) 1921-08-17 1921-08-31 Improvements to telephone networks

Country Status (2)

Country Link
FR (1) FR540090A (en)
GB (1) GB193074A (en)

Also Published As

Publication number Publication date
GB193074A (en) 1923-02-19

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