FR478877A - Sound transmission device - Google Patents

Sound transmission device

Info

Publication number
FR478877A
FR478877A FR478877DA FR478877A FR 478877 A FR478877 A FR 478877A FR 478877D A FR478877D A FR 478877DA FR 478877 A FR478877 A FR 478877A
Authority
FR
France
Prior art keywords
transmission device
sound transmission
sound
transmission
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.)
UNIVERSAL HIGH POWER TELEPHONE
Original Assignee
UNIVERSAL HIGH POWER TELEPHONE
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 UNIVERSAL HIGH POWER TELEPHONE filed Critical UNIVERSAL HIGH POWER TELEPHONE
Application granted granted Critical
Publication of FR478877A publication Critical patent/FR478877A/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
    • H04R21/00—Variable-resistance transducers
    • H04R21/02—Microphones
    • H04R21/023—Microphones with more than one granular chamber

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
FR478877D 1915-06-02 1915-06-02 Sound transmission device Expired FR478877A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR478877T 1915-06-02

Publications (1)

Publication Number Publication Date
FR478877A true FR478877A (en) 1916-01-14

Family

ID=1516332

Family Applications (1)

Application Number Title Priority Date Filing Date
FR478877D Expired FR478877A (en) 1915-06-02 1915-06-02 Sound transmission device

Country Status (1)

Country Link
FR (1) FR478877A (en)

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