JPS5245808A - Switchboard telephone circuit - Google Patents

Switchboard telephone circuit

Info

Publication number
JPS5245808A
JPS5245808A JP12197575A JP12197575A JPS5245808A JP S5245808 A JPS5245808 A JP S5245808A JP 12197575 A JP12197575 A JP 12197575A JP 12197575 A JP12197575 A JP 12197575A JP S5245808 A JPS5245808 A JP S5245808A
Authority
JP
Japan
Prior art keywords
telephone circuit
switchboard telephone
switchboard
circuit
input
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
JP12197575A
Other languages
Japanese (ja)
Inventor
Shohei Sato
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 JP12197575A priority Critical patent/JPS5245808A/en
Publication of JPS5245808A publication Critical patent/JPS5245808A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/60—Semi-automatic systems, i.e. in which the numerical selection of the outgoing line is under the control of an operator

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:The terminal impedance circuit of simple structure is inserted between 2nd input/output terminals. Thus, increase of side tone caused by impedance mismatching can be prevented economically.
JP12197575A 1975-10-08 1975-10-08 Switchboard telephone circuit Pending JPS5245808A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12197575A JPS5245808A (en) 1975-10-08 1975-10-08 Switchboard telephone circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12197575A JPS5245808A (en) 1975-10-08 1975-10-08 Switchboard telephone circuit

Publications (1)

Publication Number Publication Date
JPS5245808A true JPS5245808A (en) 1977-04-11

Family

ID=14824482

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12197575A Pending JPS5245808A (en) 1975-10-08 1975-10-08 Switchboard telephone circuit

Country Status (1)

Country Link
JP (1) JPS5245808A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4850610A (en) * 1971-10-26 1973-07-17

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4850610A (en) * 1971-10-26 1973-07-17

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