JPS51144105A - Noise-proof telephone - Google Patents

Noise-proof telephone

Info

Publication number
JPS51144105A
JPS51144105A JP6754375A JP6754375A JPS51144105A JP S51144105 A JPS51144105 A JP S51144105A JP 6754375 A JP6754375 A JP 6754375A JP 6754375 A JP6754375 A JP 6754375A JP S51144105 A JPS51144105 A JP S51144105A
Authority
JP
Japan
Prior art keywords
noise
proof telephone
proof
receiver
telephone
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.)
Granted
Application number
JP6754375A
Other languages
English (en)
Other versions
JPS5439088B2 (ja
Inventor
Hiroshi Irii
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.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone Corp
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 Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP6754375A priority Critical patent/JPS51144105A/ja
Publication of JPS51144105A publication Critical patent/JPS51144105A/ja
Publication of JPS5439088B2 publication Critical patent/JPS5439088B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/19—Arrangements of transmitters, receivers, or complete sets to prevent eavesdropping, to attenuate local noise or to prevent undesired transmission; Mouthpieces or receivers specially adapted therefor

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Headphones And Earphones (AREA)
  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
  • Telephone Set Structure (AREA)
JP6754375A 1975-06-06 1975-06-06 Noise-proof telephone Granted JPS51144105A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6754375A JPS51144105A (en) 1975-06-06 1975-06-06 Noise-proof telephone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6754375A JPS51144105A (en) 1975-06-06 1975-06-06 Noise-proof telephone

Publications (2)

Publication Number Publication Date
JPS51144105A true JPS51144105A (en) 1976-12-10
JPS5439088B2 JPS5439088B2 (ja) 1979-11-26

Family

ID=13347977

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6754375A Granted JPS51144105A (en) 1975-06-06 1975-06-06 Noise-proof telephone

Country Status (1)

Country Link
JP (1) JPS51144105A (ja)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4942730A (ja) * 1972-05-26 1974-04-22
JPS508489U (ja) * 1973-05-22 1975-01-28

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4942730A (ja) * 1972-05-26 1974-04-22
JPS508489U (ja) * 1973-05-22 1975-01-28

Also Published As

Publication number Publication date
JPS5439088B2 (ja) 1979-11-26

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