FR568339A - Improvements in telephone systems - Google Patents

Improvements in telephone systems

Info

Publication number
FR568339A
FR568339A FR568339DA FR568339A FR 568339 A FR568339 A FR 568339A FR 568339D A FR568339D A FR 568339DA FR 568339 A FR568339 A FR 568339A
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.)
INTERNAT CALLOPHONE CORP
Original Assignee
INTERNAT CALLOPHONE CORP
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 INTERNAT CALLOPHONE CORP filed Critical INTERNAT CALLOPHONE CORP
Application granted granted Critical
Publication of FR568339A publication Critical patent/FR568339A/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
    • H04M9/002—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/001—Two-way communication systems between a limited number of parties

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
FR568339D 1922-07-05 1923-07-04 Improvements in telephone systems Expired FR568339A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB568339X 1922-07-05

Publications (1)

Publication Number Publication Date
FR568339A true FR568339A (en) 1924-03-22

Family

ID=10477665

Family Applications (1)

Application Number Title Priority Date Filing Date
FR568339D Expired FR568339A (en) 1922-07-05 1923-07-04 Improvements in telephone systems

Country Status (1)

Country Link
FR (1) FR568339A (en)

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