JPS5228806A - Secret-talk circuit of push-button telephone device - Google Patents

Secret-talk circuit of push-button telephone device

Info

Publication number
JPS5228806A
JPS5228806A JP10460275A JP10460275A JPS5228806A JP S5228806 A JPS5228806 A JP S5228806A JP 10460275 A JP10460275 A JP 10460275A JP 10460275 A JP10460275 A JP 10460275A JP S5228806 A JPS5228806 A JP S5228806A
Authority
JP
Japan
Prior art keywords
secret
push
telephone device
button telephone
talk circuit
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
JP10460275A
Other languages
English (en)
Japanese (ja)
Other versions
JPS5430842B2 (it
Inventor
Kunitoshi Narita
Kazuhiko Sugai
Hideo Ohashi
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.)
Meisei Electric Co Ltd
Original Assignee
Meisei 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 Meisei Electric Co Ltd filed Critical Meisei Electric Co Ltd
Priority to JP10460275A priority Critical patent/JPS5228806A/ja
Publication of JPS5228806A publication Critical patent/JPS5228806A/ja
Publication of JPS5430842B2 publication Critical patent/JPS5430842B2/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
    • H04M1/70—Lock-out or secrecy arrangements in party-line systems

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
JP10460275A 1975-08-29 1975-08-29 Secret-talk circuit of push-button telephone device Granted JPS5228806A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10460275A JPS5228806A (en) 1975-08-29 1975-08-29 Secret-talk circuit of push-button telephone device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10460275A JPS5228806A (en) 1975-08-29 1975-08-29 Secret-talk circuit of push-button telephone device

Publications (2)

Publication Number Publication Date
JPS5228806A true JPS5228806A (en) 1977-03-04
JPS5430842B2 JPS5430842B2 (it) 1979-10-03

Family

ID=14384956

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10460275A Granted JPS5228806A (en) 1975-08-29 1975-08-29 Secret-talk circuit of push-button telephone device

Country Status (1)

Country Link
JP (1) JPS5228806A (it)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5435112U (it) * 1977-08-11 1979-03-07
JPS5481318A (en) * 1977-11-14 1979-06-28 Gen Electric Sealing composition

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS482607U (it) * 1971-05-28 1973-01-12

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS482607U (it) * 1971-05-28 1973-01-12

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5435112U (it) * 1977-08-11 1979-03-07
JPS5481318A (en) * 1977-11-14 1979-06-28 Gen Electric Sealing composition

Also Published As

Publication number Publication date
JPS5430842B2 (it) 1979-10-03

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