FR997251A - Improvements to telephone installations, in particular loudspeaker telephony - Google Patents

Improvements to telephone installations, in particular loudspeaker telephony

Info

Publication number
FR997251A
FR997251A FR997251DA FR997251A FR 997251 A FR997251 A FR 997251A FR 997251D A FR997251D A FR 997251DA FR 997251 A FR997251 A FR 997251A
Authority
FR
France
Prior art keywords
telephony
particular loudspeaker
telephone installations
installations
telephone
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
Marcel Wagner
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 FR997251A publication Critical patent/FR997251A/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
    • H04M9/001—Two-way communication systems between a limited number of parties

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
FR997251D 1945-06-25 1945-06-25 Improvements to telephone installations, in particular loudspeaker telephony Expired FR997251A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR997251T 1945-06-25

Publications (1)

Publication Number Publication Date
FR997251A true FR997251A (en) 1952-01-03

Family

ID=9558476

Family Applications (2)

Application Number Title Priority Date Filing Date
FR56444D Expired FR56444E (en) 1945-06-25
FR997251D Expired FR997251A (en) 1945-06-25 1945-06-25 Improvements to telephone installations, in particular loudspeaker telephony

Family Applications Before (1)

Application Number Title Priority Date Filing Date
FR56444D Expired FR56444E (en) 1945-06-25

Country Status (3)

Country Link
BE (1) BE460657A (en)
FR (2) FR997251A (en)
LU (1) LU27795A1 (en)

Also Published As

Publication number Publication date
FR56444E (en) 1952-10-07
BE460657A (en)
LU27795A1 (en)

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