FR987601A - Charcoal microphone capsule for telephone transmissions and various applications - Google Patents

Charcoal microphone capsule for telephone transmissions and various applications

Info

Publication number
FR987601A
FR987601A FR987601DA FR987601A FR 987601 A FR987601 A FR 987601A FR 987601D A FR987601D A FR 987601DA FR 987601 A FR987601 A FR 987601A
Authority
FR
France
Prior art keywords
charcoal
various applications
microphone capsule
telephone transmissions
transmissions
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
Pierre-Albert-Alexan Rault
Roger-Charles-Louis Prudon
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.)
Compagnie Industrielle des Telephones SA
Original Assignee
Compagnie Industrielle des Telephones SA
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 Compagnie Industrielle des Telephones SA filed Critical Compagnie Industrielle des Telephones SA
Application granted granted Critical
Publication of FR987601A publication Critical patent/FR987601A/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; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
    • H04R21/00—Variable-resistance transducers
    • H04R21/02—Microphones
    • H04R21/021—Microphones with granular resistance material

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
FR987601D 1949-04-06 1949-04-06 Charcoal microphone capsule for telephone transmissions and various applications Expired FR987601A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR987601T 1949-04-06

Publications (1)

Publication Number Publication Date
FR987601A true FR987601A (en) 1951-08-16

Family

ID=9539031

Family Applications (1)

Application Number Title Priority Date Filing Date
FR987601D Expired FR987601A (en) 1949-04-06 1949-04-06 Charcoal microphone capsule for telephone transmissions and various applications

Country Status (2)

Country Link
FR (1) FR987601A (en)
NL (1) NL72183C (en)

Also Published As

Publication number Publication date
NL72183C (en)

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