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JPS5676666A - Detection circuit for call-out signal - Google Patents

Detection circuit for call-out signal

Info

Publication number
JPS5676666A
JPS5676666A JP15460279A JP15460279A JPS5676666A JP S5676666 A JPS5676666 A JP S5676666A JP 15460279 A JP15460279 A JP 15460279A JP 15460279 A JP15460279 A JP 15460279A JP S5676666 A JPS5676666 A JP S5676666A
Authority
JP
Japan
Prior art keywords
signal
circuit
call
out signal
level
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
JP15460279A
Other languages
Japanese (ja)
Inventor
Matsuhiko Watanabe
Kiyoyuki Tsujimura
Shigenori Okamoto
Koichi Ito
Akio Goto
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.)
Toshiba Corp
Nippon Telegraph and Telephone Corp
Original Assignee
Toshiba Corp
Nippon Telegraph and Telephone Corp
Tokyo Shibaura 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 Toshiba Corp, Nippon Telegraph and Telephone Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP15460279A priority Critical patent/JPS5676666A/en
Publication of JPS5676666A publication Critical patent/JPS5676666A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/82—Line monitoring circuits for call progress or status discrimination

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)

Abstract

PURPOSE:To enable detection with sure discrimination of call-out signal from other signals, by signal processing through the differentiation of callout signal. CONSTITUTION:When callout signal voltage appears between the input terminals L1 and L2, it is differentiated a differentiation circuit 1, the current of a half wave flows to a light emitting diode 5 for illumination and a current flows to a phototransistor 6, the signal appeared at the collector is converted into binary signal at wave shape circuit 9 to obtain comparatively wide pulse train at point d, and when this is integrated at an integration circuit 10, the level corresponding to the pulse width is obtained. By discriminating the voltage level at a level discrimination circuit 15, the call-out signal is detected. When the dial signal is input from the telephone set connected in parallel, the maximum value of the differentiating current at the differentiation circuit 1 is greater than the call-out signal, but since the width is narrow, then the output of the wave shape circuit 9 is narrow, and since the output level of an integrating circuit 15 is smaller than the call-out signal, no detection output is appeared.
JP15460279A 1979-11-29 1979-11-29 Detection circuit for call-out signal Pending JPS5676666A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15460279A JPS5676666A (en) 1979-11-29 1979-11-29 Detection circuit for call-out signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15460279A JPS5676666A (en) 1979-11-29 1979-11-29 Detection circuit for call-out signal

Publications (1)

Publication Number Publication Date
JPS5676666A true JPS5676666A (en) 1981-06-24

Family

ID=15587763

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15460279A Pending JPS5676666A (en) 1979-11-29 1979-11-29 Detection circuit for call-out signal

Country Status (1)

Country Link
JP (1) JPS5676666A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59178851A (en) * 1983-03-30 1984-10-11 Toshiba Corp Telephone set circuit
JPS61121044U (en) * 1985-01-16 1986-07-30
JPH0213160A (en) * 1988-06-30 1990-01-17 Sony Corp Call signal detector

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5044706A (en) * 1973-08-22 1975-04-22
JPS5332604A (en) * 1976-09-07 1978-03-28 Tad Avanti Circuit for detecting receiving signal

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5044706A (en) * 1973-08-22 1975-04-22
JPS5332604A (en) * 1976-09-07 1978-03-28 Tad Avanti Circuit for detecting receiving signal

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59178851A (en) * 1983-03-30 1984-10-11 Toshiba Corp Telephone set circuit
JPH057909B2 (en) * 1983-03-30 1993-01-29 Tokyo Shibaura Electric Co
JPS61121044U (en) * 1985-01-16 1986-07-30
JPH0213160A (en) * 1988-06-30 1990-01-17 Sony Corp Call signal detector

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