JPS5639669A - Loud telephone unit - Google Patents

Loud telephone unit

Info

Publication number
JPS5639669A
JPS5639669A JP11558579A JP11558579A JPS5639669A JP S5639669 A JPS5639669 A JP S5639669A JP 11558579 A JP11558579 A JP 11558579A JP 11558579 A JP11558579 A JP 11558579A JP S5639669 A JPS5639669 A JP S5639669A
Authority
JP
Japan
Prior art keywords
microphone
speaker
base
group part
axis
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.)
Pending
Application number
JP11558579A
Other languages
Japanese (ja)
Inventor
Kiyoyasu Miyawaki
Tetsuo Ishizaka
Atsuji Takeda
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric 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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP11558579A priority Critical patent/JPS5639669A/en
Publication of JPS5639669A publication Critical patent/JPS5639669A/en
Pending 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
    • H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers

Landscapes

  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)

Abstract

PURPOSE:To obtain the excellent performance of calling with ringing torelance increased by arraying microphone units at random equal intervals in a line and by arranging a speaker on the same axis with the array. CONSTITUTION:Microphone units 4-1-4-n are arrayed at intervals a half the wavelength of an acoustic wave of the maximum inuse frequency of microphone group part 3 and the number of microphone arrayed in a line is made euqivalent to the wavelength of an acoustic wave of the minimum inuse frequency. Linear fitting base 2, where microphone group part 3 and speaker part 5 are fixed, makes it possible to arrange the front surface of the speaker opening part on the axis of microphone group part 3. In order to amplify a sound from a receiving sound source over a broad range, speakers 6-1-6-8 are arranged in the circumferential direction having its axis on base 2 perpendicular to the floor and base 2 is fitted with transmitter 7, dial 8 and belt 9.
JP11558579A 1979-09-08 1979-09-08 Loud telephone unit Pending JPS5639669A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11558579A JPS5639669A (en) 1979-09-08 1979-09-08 Loud telephone unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11558579A JPS5639669A (en) 1979-09-08 1979-09-08 Loud telephone unit

Publications (1)

Publication Number Publication Date
JPS5639669A true JPS5639669A (en) 1981-04-15

Family

ID=14666226

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11558579A Pending JPS5639669A (en) 1979-09-08 1979-09-08 Loud telephone unit

Country Status (1)

Country Link
JP (1) JPS5639669A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56143264A (en) * 1980-04-11 1981-11-07 Sangou Toki Kk Paint assuming noble metallic color
JPS6234962A (en) * 1985-08-07 1987-02-14 メルク・パテント・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング Pearl gloss pigment having iron oxide coating layer

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56143264A (en) * 1980-04-11 1981-11-07 Sangou Toki Kk Paint assuming noble metallic color
JPS623783B2 (en) * 1980-04-11 1987-01-27 Sango Toki Kk
JPS6234962A (en) * 1985-08-07 1987-02-14 メルク・パテント・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング Pearl gloss pigment having iron oxide coating layer

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