JPS56157167A - Telephone channel connection circuit for network control device - Google Patents

Telephone channel connection circuit for network control device

Info

Publication number
JPS56157167A
JPS56157167A JP6092880A JP6092880A JPS56157167A JP S56157167 A JPS56157167 A JP S56157167A JP 6092880 A JP6092880 A JP 6092880A JP 6092880 A JP6092880 A JP 6092880A JP S56157167 A JPS56157167 A JP S56157167A
Authority
JP
Japan
Prior art keywords
terminal
data transmitting
base
transmitting equipment
transistor
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
JP6092880A
Other languages
Japanese (ja)
Inventor
Tatsuo Matsubara
Toshiyuki Taguchi
Junichi Takahashi
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
Nippon Telegraph and Telephone Corp
Original Assignee
NEC Corp
Nippon Telegraph and Telephone 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 Telegraph and Telephone Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP6092880A priority Critical patent/JPS56157167A/en
Publication of JPS56157167A publication Critical patent/JPS56157167A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
    • H04M11/06—Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

PURPOSE:To avoid the bell ringing for the telephones on the same circuit when a power source is applied to a data transmitting equipment, by providing a transistor circuit consisting of a transistor, a resistance, a capacitor and a diode between a subscriber telephone side and the data transmitting equipment side. CONSTITUTION:A telephone switchboard reverse the polarity between the terminals 1 and 2 to start a data transmitting equipment. The terminal 1 is connected to the collector of a switching transistor TR and the anode of a diode RC. Then the base of the TR is connected to a resistor R and a capacitor C of a charging circuit; the other end of the R is connected to the base of the TR; the emitter of the TR is connected to the terminal 3; and the terminal 2 is connected to the other end of the C and the terminal 4 respectively. When a start is given from a telephone switchboard, the voltage of the TR base varies by the CR time constant. And the larger the CR time constant, the more the both-end voltages of a load RL changes gradually. Thus a bell ring caused by a sudden change of the voltage between the terminals 1 and 2 is avoided.
JP6092880A 1980-05-08 1980-05-08 Telephone channel connection circuit for network control device Pending JPS56157167A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6092880A JPS56157167A (en) 1980-05-08 1980-05-08 Telephone channel connection circuit for network control device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6092880A JPS56157167A (en) 1980-05-08 1980-05-08 Telephone channel connection circuit for network control device

Publications (1)

Publication Number Publication Date
JPS56157167A true JPS56157167A (en) 1981-12-04

Family

ID=13156527

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6092880A Pending JPS56157167A (en) 1980-05-08 1980-05-08 Telephone channel connection circuit for network control device

Country Status (1)

Country Link
JP (1) JPS56157167A (en)

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