FR728902A - Recording device by amplifying sounds and in particular telephone conversations - Google Patents

Recording device by amplifying sounds and in particular telephone conversations

Info

Publication number
FR728902A
FR728902A FR728902DA FR728902A FR 728902 A FR728902 A FR 728902A FR 728902D A FR728902D A FR 728902DA FR 728902 A FR728902 A FR 728902A
Authority
FR
France
Prior art keywords
recording device
particular telephone
telephone conversations
amplifying sounds
sounds
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
Constant Frere
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 FR728902A publication Critical patent/FR728902A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/64—Automatic arrangements for answering calls; Automatic arrangements for recording messages for absent subscribers; Arrangements for recording conversations
    • H04M1/65—Recording arrangements for recording a message from the calling party

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
FR728902D 1931-12-29 1931-12-29 Recording device by amplifying sounds and in particular telephone conversations Expired FR728902A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR728902T 1931-12-29

Publications (1)

Publication Number Publication Date
FR728902A true FR728902A (en) 1932-07-13

Family

ID=9112095

Family Applications (1)

Application Number Title Priority Date Filing Date
FR728902D Expired FR728902A (en) 1931-12-29 1931-12-29 Recording device by amplifying sounds and in particular telephone conversations

Country Status (1)

Country Link
FR (1) FR728902A (en)

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