FR734338A - Perfectionnements aux appareils d'écoute - Google Patents

Perfectionnements aux appareils d'écoute

Info

Publication number
FR734338A
FR734338A FR734338DA FR734338A FR 734338 A FR734338 A FR 734338A FR 734338D A FR734338D A FR 734338DA FR 734338 A FR734338 A FR 734338A
Authority
FR
France
Prior art keywords
listening devices
listening
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)
Inventor
Francois Canac
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 filed Critical
Application granted granted Critical
Publication of FR734338A publication Critical patent/FR734338A/fr
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
    • G01S1/72—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using ultrasonic, sonic or infrasonic waves

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
FR734338D 1931-07-01 1931-07-01 Perfectionnements aux appareils d'écoute Expired FR734338A (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR734338T 1931-07-01

Publications (1)

Publication Number Publication Date
FR734338A true FR734338A (fr) 1932-10-19

Family

ID=9128762

Family Applications (1)

Application Number Title Priority Date Filing Date
FR734338D Expired FR734338A (fr) 1931-07-01 1931-07-01 Perfectionnements aux appareils d'écoute

Country Status (1)

Country Link
FR (1) FR734338A (fr)

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