FR577421A - Improvements to sound receiving devices - Google Patents

Improvements to sound receiving devices

Info

Publication number
FR577421A
FR577421A FR577421DA FR577421A FR 577421 A FR577421 A FR 577421A FR 577421D A FR577421D A FR 577421DA FR 577421 A FR577421 A FR 577421A
Authority
FR
France
Prior art keywords
receiving devices
sound receiving
sound
devices
receiving
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.)
WALKER SIGNAL AND EQUIPMENT CO
Original Assignee
WALKER SIGNAL AND EQUIPMENT CO
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 WALKER SIGNAL AND EQUIPMENT CO filed Critical WALKER SIGNAL AND EQUIPMENT CO
Application granted granted Critical
Publication of FR577421A publication Critical patent/FR577421A/en
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)
FR577421D 1924-02-19 1924-02-19 Improvements to sound receiving devices Expired FR577421A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR577421T 1924-02-19

Publications (1)

Publication Number Publication Date
FR577421A true FR577421A (en) 1924-09-05

Family

ID=8954729

Family Applications (1)

Application Number Title Priority Date Filing Date
FR577421D Expired FR577421A (en) 1924-02-19 1924-02-19 Improvements to sound receiving devices

Country Status (1)

Country Link
FR (1) FR577421A (en)

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