JPS52141105A - Privacy talk system for key telephone - Google Patents

Privacy talk system for key telephone

Info

Publication number
JPS52141105A
JPS52141105A JP5749576A JP5749576A JPS52141105A JP S52141105 A JPS52141105 A JP S52141105A JP 5749576 A JP5749576 A JP 5749576A JP 5749576 A JP5749576 A JP 5749576A JP S52141105 A JPS52141105 A JP S52141105A
Authority
JP
Japan
Prior art keywords
privacy
key telephone
talk system
talk
control
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
JP5749576A
Other languages
English (en)
Japanese (ja)
Other versions
JPS567628B2 (OSRAM
Inventor
Juichi Takano
Koichi Sekiguchi
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.)
Iwatsu Electric Co Ltd
Original Assignee
Iwatsu 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 Iwatsu Electric Co Ltd filed Critical Iwatsu Electric Co Ltd
Priority to JP5749576A priority Critical patent/JPS52141105A/ja
Publication of JPS52141105A publication Critical patent/JPS52141105A/ja
Priority to US05/967,017 priority patent/US4254306A/en
Publication of JPS567628B2 publication Critical patent/JPS567628B2/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
    • H04M1/68—Circuit arrangements for preventing eavesdropping

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
JP5749576A 1975-12-26 1976-05-19 Privacy talk system for key telephone Granted JPS52141105A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP5749576A JPS52141105A (en) 1976-05-19 1976-05-19 Privacy talk system for key telephone
US05/967,017 US4254306A (en) 1975-12-26 1978-12-06 Key telephone system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5749576A JPS52141105A (en) 1976-05-19 1976-05-19 Privacy talk system for key telephone

Publications (2)

Publication Number Publication Date
JPS52141105A true JPS52141105A (en) 1977-11-25
JPS567628B2 JPS567628B2 (OSRAM) 1981-02-18

Family

ID=13057297

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5749576A Granted JPS52141105A (en) 1975-12-26 1976-05-19 Privacy talk system for key telephone

Country Status (1)

Country Link
JP (1) JPS52141105A (OSRAM)

Also Published As

Publication number Publication date
JPS567628B2 (OSRAM) 1981-02-18

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