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JPS55105485A - Trunk circuit of automatic telephone exchange - Google Patents

Trunk circuit of automatic telephone exchange

Info

Publication number
JPS55105485A
JPS55105485A JP1297179A JP1297179A JPS55105485A JP S55105485 A JPS55105485 A JP S55105485A JP 1297179 A JP1297179 A JP 1297179A JP 1297179 A JP1297179 A JP 1297179A JP S55105485 A JPS55105485 A JP S55105485A
Authority
JP
Japan
Prior art keywords
circuit
current
lines
trunk circuit
detecting 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
JP1297179A
Other languages
Japanese (ja)
Other versions
JPS6214159B2 (en
Inventor
Mitsuo Suzuki
Isamu Yamane
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 JP1297179A priority Critical patent/JPS55105485A/en
Publication of JPS55105485A publication Critical patent/JPS55105485A/en
Publication of JPS6214159B2 publication Critical patent/JPS6214159B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:To realize the miniaturization of the trunk circuit by connecting the current direction detecting circuit in parallel to the impedance to connected to the DC current path of the trunk circuit of the telephone circuit and then carrying out the signal transmission and reception among the automatic exchanges while the detection output of the current direction detecting circuit exists. CONSTITUTION:Coil RPTA is connected in series between call lines LA and LB to the trunk circuit which receives the signals among the exchanges via the direct current flowing to lines LA and LB which connect the two automatic telephone exhanges. In addition, comparator IC2 to detect the direction of the current flowing to lines LA and LB plus the current direction detecting circuit consisting of diodes D6 and D7 are installed in parallel to coil RPTA. And in case the current featuring the same direction as that to the 2nd input terminal from the 1st input terminal of the above detecting circuit exists at lines LA and LB each, the current direction is detected. And the prescribed output is applied to control circuit CONT via lead (2) to actuate relays A0-A1 plus OG. Thus the control is given to contacts a0 and a1 of the trunk circuit plus contact Og as well.
JP1297179A 1979-02-07 1979-02-07 Trunk circuit of automatic telephone exchange Granted JPS55105485A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1297179A JPS55105485A (en) 1979-02-07 1979-02-07 Trunk circuit of automatic telephone exchange

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1297179A JPS55105485A (en) 1979-02-07 1979-02-07 Trunk circuit of automatic telephone exchange

Publications (2)

Publication Number Publication Date
JPS55105485A true JPS55105485A (en) 1980-08-13
JPS6214159B2 JPS6214159B2 (en) 1987-03-31

Family

ID=11820108

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1297179A Granted JPS55105485A (en) 1979-02-07 1979-02-07 Trunk circuit of automatic telephone exchange

Country Status (1)

Country Link
JP (1) JPS55105485A (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5291604A (en) * 1976-01-26 1977-08-02 Western Electric Co Device for extending range of raising battery voltage
JPS53128208A (en) * 1977-04-14 1978-11-09 Nec Corp Ringer signal detector circuit

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5291604A (en) * 1976-01-26 1977-08-02 Western Electric Co Device for extending range of raising battery voltage
JPS53128208A (en) * 1977-04-14 1978-11-09 Nec Corp Ringer signal detector circuit

Also Published As

Publication number Publication date
JPS6214159B2 (en) 1987-03-31

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