FR27785E - Improvements to so-called speaker phones - Google Patents

Improvements to so-called speaker phones

Info

Publication number
FR27785E
FR27785E FR27785DA FR27785E FR 27785 E FR27785 E FR 27785E FR 27785D A FR27785D A FR 27785DA FR 27785 E FR27785 E FR 27785E
Authority
FR
France
Prior art keywords
speaker phones
called speaker
called
phones
speaker
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.)
Societe Francaise Radio Electrique
Original Assignee
Societe Francaise Radio Electrique
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 Societe Francaise Radio Electrique filed Critical Societe Francaise Radio Electrique
Application granted granted Critical
Publication of FR27785E publication Critical patent/FR27785E/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R7/00—Diaphragms for electromechanical transducers; Cones
    • H04R7/02—Diaphragms for electromechanical transducers; Cones characterised by the construction
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only 
    • H04R1/225—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only  for telephonic receivers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R7/00—Diaphragms for electromechanical transducers; Cones
    • H04R7/02—Diaphragms for electromechanical transducers; Cones characterised by the construction
    • H04R7/04—Plane diaphragms
    • H04R7/06—Plane diaphragms comprising a plurality of sections or layers

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
FR27785D 1923-02-20 1923-02-20 Improvements to so-called speaker phones Expired FR27785E (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR27785T 1923-02-20

Publications (1)

Publication Number Publication Date
FR27785E true FR27785E (en) 1924-08-18

Family

ID=8666057

Family Applications (3)

Application Number Title Priority Date Filing Date
FR562221D Expired FR562221A (en) 1923-02-20 1922-04-06 Improvements to so-called speaker phones
FR27354D Expired FR27354E (en) 1923-02-20 1922-11-27 Improvements to so-called telephones
FR27785D Expired FR27785E (en) 1923-02-20 1923-02-20 Improvements to so-called speaker phones

Family Applications Before (2)

Application Number Title Priority Date Filing Date
FR562221D Expired FR562221A (en) 1923-02-20 1922-04-06 Improvements to so-called speaker phones
FR27354D Expired FR27354E (en) 1923-02-20 1922-11-27 Improvements to so-called telephones

Country Status (1)

Country Link
FR (3) FR562221A (en)

Also Published As

Publication number Publication date
FR562221A (en) 1923-11-07
FR27354E (en) 1924-06-24

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