JPS5452909A - Dial pulse detection system - Google Patents

Dial pulse detection system

Info

Publication number
JPS5452909A
JPS5452909A JP11963277A JP11963277A JPS5452909A JP S5452909 A JPS5452909 A JP S5452909A JP 11963277 A JP11963277 A JP 11963277A JP 11963277 A JP11963277 A JP 11963277A JP S5452909 A JPS5452909 A JP S5452909A
Authority
JP
Japan
Prior art keywords
dial pulse
circuit
threshold level
detected
detection system
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
JP11963277A
Other languages
Japanese (ja)
Inventor
Shigeo Kamata
Kiyobumi Hayashi
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP11963277A priority Critical patent/JPS5452909A/en
Publication of JPS5452909A publication Critical patent/JPS5452909A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/32—Signalling arrangements; Manipulation of signalling currents using trains of dc pulses

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)

Abstract

PURPOSE:To prevent the transient vibration current from being detected erroneously as the dial pulse, by securing an automatic setting of the threshold level corresponding to the dial pulse level. CONSTITUTION:The current flowing between the telephone and the exchange is detected through circuit 1 and then memorized in current value memory circuit 2 at least for the dial pulse receiving period. This memory contents is added to threshold level control circuit 3 to control the threshold level at threshold level circuit 4 where the dial pulse is detected. Then delay switching circuit 5 resets the circuit after end of the dial pulse reception to get ready for reception of the next dial pulse.
JP11963277A 1977-10-05 1977-10-05 Dial pulse detection system Pending JPS5452909A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11963277A JPS5452909A (en) 1977-10-05 1977-10-05 Dial pulse detection system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11963277A JPS5452909A (en) 1977-10-05 1977-10-05 Dial pulse detection system

Publications (1)

Publication Number Publication Date
JPS5452909A true JPS5452909A (en) 1979-04-25

Family

ID=14766243

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11963277A Pending JPS5452909A (en) 1977-10-05 1977-10-05 Dial pulse detection system

Country Status (1)

Country Link
JP (1) JPS5452909A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57104862U (en) * 1980-12-19 1982-06-28

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57104862U (en) * 1980-12-19 1982-06-28

Similar Documents

Publication Publication Date Title
JPS55109042A (en) Selective individual calling system
JPS57171868A (en) Waveform shaping circuit
JPS54118723A (en) Phase converter
JPS5356903A (en) Automatic level control circuit for telephone set
JPS5418663A (en) Gate control unit for thyristor valve
GB1452616A (en) Phase comparison relaying apparatus with two-count by-pass circuit
JPS5452909A (en) Dial pulse detection system
IT8022533A0 (en) CURRENT DETECTION CIRCUIT COMPLEX FOR AN AUTOMATIC TELEPHONE SWITCHBOARD.
JPS5764398A (en) Memory device
JPS53109449A (en) Control system for data transmission
JPS53117922A (en) Absence reception voice answer skip system
JPS5343854A (en) Overcurrent detection circuit
JPS5680921A (en) Automatic tuning circuit
JPS5390707A (en) Detecting system for circuit fault
JPS5368010A (en) Ring trip circuit
JPS53138117A (en) Automatic gain control unit
JPS5220067A (en) Peak detecting circuit
JPS54103526A (en) Electrical route insulation resistance supervising device
JPS5392450A (en) Current limiting device
JPS52154672A (en) Timer device
JPS549389A (en) Temprature controller
JPS535719A (en) Dc-dc convertor
JPS57194627A (en) Protecting device for load control circuit
JPS54108503A (en) Switching control system
JPS5414643A (en) Data channel