JPS57107670A - Public telephone set for consignment - Google Patents

Public telephone set for consignment

Info

Publication number
JPS57107670A
JPS57107670A JP18446080A JP18446080A JPS57107670A JP S57107670 A JPS57107670 A JP S57107670A JP 18446080 A JP18446080 A JP 18446080A JP 18446080 A JP18446080 A JP 18446080A JP S57107670 A JPS57107670 A JP S57107670A
Authority
JP
Japan
Prior art keywords
callout
hook
taking
relay
positive polarity
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
JP18446080A
Other languages
Japanese (ja)
Other versions
JPS6333753B2 (en
Inventor
Sadao Saito
Keisuke Tanaka
Junji Nakada
Hideaki Teramura
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
Tamura Electric Works Ltd
Original Assignee
Nippon Telegraph and Telephone Corp
Tamura Electric Works 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 Nippon Telegraph and Telephone Corp, Tamura Electric Works Ltd filed Critical Nippon Telegraph and Telephone Corp
Priority to JP18446080A priority Critical patent/JPS57107670A/en
Publication of JPS57107670A publication Critical patent/JPS57107670A/en
Publication of JPS6333753B2 publication Critical patent/JPS6333753B2/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
    • H04M1/66—Substation equipment, e.g. for use by subscribers with means for preventing unauthorised or fraudulent calling
    • H04M1/667—Preventing unauthorised calls from a telephone set
    • H04M1/67—Preventing unauthorised calls from a telephone set by electronic means

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Signal Processing (AREA)
  • Prepayment Telephone Systems (AREA)

Abstract

PURPOSE:To make handling of collect-call or the like easy, by making the response operation not using channel key ineffective to a callout signal transmitted from a general exchanger and enabling response to a DC voltage taking the line terminal as positive after the transmission of callout signal only with AC component. CONSTITUTION:At one-hook waiting state, when a callout signal is incoming, a bell BL rings and a hook switch HS<2> is switched through off-hook. A half wave of a callout signal taking a line terminal L2 as positive polarity flows to an incoming detection relay RR, which is activated and self-held with a permanent magnet. At this state, even if off-hook is made, since the DC component superimposed on the callout signal by taking the line L2 as positive polarity is blocked at a diode D7, an exchanger detects no response operation. When a consignment person operates a channel key, the operation of a relay RR is blocked to be entered to call state. After the operation of the relay RR is made with the callout only with the AC component, when the line L1 is taken as the positive polarity, an SCR is operative and a person other than the consiggment person can respond.
JP18446080A 1980-12-25 1980-12-25 Public telephone set for consignment Granted JPS57107670A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP18446080A JPS57107670A (en) 1980-12-25 1980-12-25 Public telephone set for consignment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP18446080A JPS57107670A (en) 1980-12-25 1980-12-25 Public telephone set for consignment

Publications (2)

Publication Number Publication Date
JPS57107670A true JPS57107670A (en) 1982-07-05
JPS6333753B2 JPS6333753B2 (en) 1988-07-06

Family

ID=16153533

Family Applications (1)

Application Number Title Priority Date Filing Date
JP18446080A Granted JPS57107670A (en) 1980-12-25 1980-12-25 Public telephone set for consignment

Country Status (1)

Country Link
JP (1) JPS57107670A (en)

Also Published As

Publication number Publication date
JPS6333753B2 (en) 1988-07-06

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