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FR709525A - Perfectionnements aux dispositifs d'intercommunication - Google Patents

Perfectionnements aux dispositifs d'intercommunication

Info

Publication number
FR709525A
FR709525A FR709525DA FR709525A FR 709525 A FR709525 A FR 709525A FR 709525D A FR709525D A FR 709525DA FR 709525 A FR709525 A FR 709525A
Authority
FR
France
Prior art keywords
intercommunication devices
intercommunication
devices
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.)
Marconis Wireless Telegraph Co Ltd
BAE Systems Electronics Ltd
Original Assignee
Marconis Wireless Telegraph Co Ltd
Marconi Co Ltd
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 Marconis Wireless Telegraph Co Ltd, Marconi Co Ltd filed Critical Marconis Wireless Telegraph Co Ltd
Application granted granted Critical
Publication of FR709525A publication Critical patent/FR709525A/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; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
    • H04R1/38—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means in which sound waves act upon both sides of a diaphragm and incorporating acoustic phase-shifting means, e.g. pressure-gradient microphone

Landscapes

  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
FR709525D 1930-02-14 1931-01-16 Perfectionnements aux dispositifs d'intercommunication Expired FR709525A (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB709525X 1930-02-14

Publications (1)

Publication Number Publication Date
FR709525A true FR709525A (fr) 1931-08-07

Family

ID=10494246

Family Applications (1)

Application Number Title Priority Date Filing Date
FR709525D Expired FR709525A (fr) 1930-02-14 1931-01-16 Perfectionnements aux dispositifs d'intercommunication

Country Status (1)

Country Link
FR (1) FR709525A (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1041087B (de) * 1955-07-19 1958-10-16 Wendton Werner Wendt K G Elektromagnetische Hoervorrichtung, insbesondere Hoerbrille

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1041087B (de) * 1955-07-19 1958-10-16 Wendton Werner Wendt K G Elektromagnetische Hoervorrichtung, insbesondere Hoerbrille

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