JPS5521651A - Ring trip circuit - Google Patents

Ring trip circuit

Info

Publication number
JPS5521651A
JPS5521651A JP9477578A JP9477578A JPS5521651A JP S5521651 A JPS5521651 A JP S5521651A JP 9477578 A JP9477578 A JP 9477578A JP 9477578 A JP9477578 A JP 9477578A JP S5521651 A JPS5521651 A JP S5521651A
Authority
JP
Japan
Prior art keywords
output
ring trip
bell signal
voltage
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.)
Pending
Application number
JP9477578A
Other languages
Japanese (ja)
Inventor
Kunio Nagashima
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 JP9477578A priority Critical patent/JPS5521651A/en
Publication of JPS5521651A publication Critical patent/JPS5521651A/en
Pending legal-status Critical Current

Links

Landscapes

  • Devices For Supply Of Signal Current (AREA)

Abstract

PURPOSE: To enable the ring trip with small and light weight and with easy circuit integration, by switching the relay contact through the operation of the controller with the output of the voltage comparator.
CONSTITUTION: The bell signal supply circuit 204 delivers the bell signal superimposing DC voltage between the two communication wires via the resistors 203 and 208 having a given resistance value. Further, the relay contacts 202 and 207 are placed between the circuit 204 and the power supply 209. Each line of the communication lines is connected to the differential amplifier 210, the output connects the LPF 211 having lower cut off frequency than the frequency of the bell signal, the output of the PLF 211 is connected with the voltage comparator 213 having a given threshold voltage, and this output activates the controller 214 to switch the relay contacts 202 and 207. Thus, ring trip can be made with small size, light weight and easy circuit integration.
COPYRIGHT: (C)1980,JPO&Japio
JP9477578A 1978-08-02 1978-08-02 Ring trip circuit Pending JPS5521651A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9477578A JPS5521651A (en) 1978-08-02 1978-08-02 Ring trip circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9477578A JPS5521651A (en) 1978-08-02 1978-08-02 Ring trip circuit

Publications (1)

Publication Number Publication Date
JPS5521651A true JPS5521651A (en) 1980-02-15

Family

ID=14119464

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9477578A Pending JPS5521651A (en) 1978-08-02 1978-08-02 Ring trip circuit

Country Status (1)

Country Link
JP (1) JPS5521651A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57212857A (en) * 1981-06-25 1982-12-27 Fujitsu Ltd Ring top circuit
JPS5888953A (en) * 1981-11-20 1983-05-27 Fujitsu Ltd Ring trip circuit
JPS6423659A (en) * 1987-07-20 1989-01-26 Fujitsu Ltd Ring trip circuit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5395509A (en) * 1977-01-28 1978-08-21 Western Electric Co Telephone loop current detector

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5395509A (en) * 1977-01-28 1978-08-21 Western Electric Co Telephone loop current detector

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57212857A (en) * 1981-06-25 1982-12-27 Fujitsu Ltd Ring top circuit
JPS5888953A (en) * 1981-11-20 1983-05-27 Fujitsu Ltd Ring trip circuit
JPS6423659A (en) * 1987-07-20 1989-01-26 Fujitsu Ltd Ring trip circuit

Similar Documents

Publication Publication Date Title
JPS5521651A (en) Ring trip circuit
JPS526550A (en) 2-wire type conversion amplifier
JPS5392603A (en) Line branching unit
GB1527962A (en) Electrical protection apparatus
JPS57147328A (en) Input circuit
JPS5555605A (en) Protective circuit for power output circuit
JPS51123665A (en) A d,c output circuit
JPS6415821A (en) 3-state control system
JPS5232551A (en) Switch control circuit
JPS53911A (en) Speech current disconnection circuit
JPS5395562A (en) Switch
JPS54127544A (en) Multifunction protective relay
JPS5518106A (en) Switch circuit
JPS5319800A (en) Receiving circuit of fire alarms
JPS54129333A (en) Alternating current direct current duplicating application
JPS5337371A (en) Switch circuit
JPS524720A (en) Two-ways constant current circuit
JPS5221653A (en) Dc voltage converter
JPS57135528A (en) Switching circuit of high-frequency radio equipment
JPS5329602A (en) Power supply connection circuit
JPS5396449A (en) Protective relaying equipment
JPS52104729A (en) A.c. d.c. change over equipment
JPS5580128A (en) Switching type constant-voltage circuit
JPS54160103A (en) Ring trip circuit
JPS53136414A (en) Sending system for subscriber's line signal