FR690230A - Microphone à grenaille de charbon - Google Patents

Microphone à grenaille de charbon

Info

Publication number
FR690230A
FR690230A FR690230DA FR690230A FR 690230 A FR690230 A FR 690230A FR 690230D A FR690230D A FR 690230DA FR 690230 A FR690230 A FR 690230A
Authority
FR
France
Prior art keywords
charcoal
shot
microphone
shot microphone
charcoal shot
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
English (en)
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.)
Koninklijke Philips NV
Original Assignee
Philips Gloeilampenfabrieken NV
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 Philips Gloeilampenfabrieken NV filed Critical Philips Gloeilampenfabrieken NV
Application granted granted Critical
Publication of FR690230A publication Critical patent/FR690230A/fr
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
    • H04R21/026—Microphones in which the sound is perpendicular to the current crossing the transducer material

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Pyridine Compounds (AREA)
FR690230D 1929-03-02 1930-02-19 Microphone à grenaille de charbon Expired FR690230A (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL338814X 1929-03-02

Publications (1)

Publication Number Publication Date
FR690230A true FR690230A (fr) 1930-09-17

Family

ID=19784625

Family Applications (1)

Application Number Title Priority Date Filing Date
FR690230D Expired FR690230A (fr) 1929-03-02 1930-02-19 Microphone à grenaille de charbon

Country Status (2)

Country Link
FR (1) FR690230A (fr)
GB (1) GB338814A (fr)

Also Published As

Publication number Publication date
GB338814A (en) 1930-11-27

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