JPS5660151A - Level-compensating type handset unit - Google Patents

Level-compensating type handset unit

Info

Publication number
JPS5660151A
JPS5660151A JP13613379A JP13613379A JPS5660151A JP S5660151 A JPS5660151 A JP S5660151A JP 13613379 A JP13613379 A JP 13613379A JP 13613379 A JP13613379 A JP 13613379A JP S5660151 A JPS5660151 A JP S5660151A
Authority
JP
Japan
Prior art keywords
amplifier
output
terminals
compensating circuit
point
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
JP13613379A
Other languages
Japanese (ja)
Inventor
Hideo Fukazawa
Masataka Arai
Yuichi Mejiro
Jiro Ikenaga
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
Kanda Tsushin Kogyo Co Ltd
Original Assignee
Fujitsu Ltd
Kanda Tsushin Kogyo 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 Fujitsu Ltd, Kanda Tsushin Kogyo Co Ltd filed Critical Fujitsu Ltd
Priority to JP13613379A priority Critical patent/JPS5660151A/en
Publication of JPS5660151A publication Critical patent/JPS5660151A/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
    • H04M1/738—Interface circuits for coupling substations to external telephone lines
    • H04M1/76—Compensating for differences in line impedance

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Circuit For Audible Band Transducer (AREA)

Abstract

PURPOSE:To compensate the output of a sound signal by interposing the compensating circuit, composed of a nonlinear resistance such as a varistor and a resistance connected in series, between the connection point of a rectifying circuit and amplifier and the earth. CONSTITUTION:The output of solid-state transmitter M is amplified by amplifier A. Then, polarity-identity diode connection rectifier REC for supplying amplifier A with driving electric power of constant polarity regardless of characteristics of DC electric power supplied to connection terminals T1 and T2 is provided. Between the earth and the coupling point between output point DI and the connection point of diodes D1 and D2 of this rectifier REC, the compensating circuit composed of a nonlinear resistance such as a varistor and a resistance connected in series is interposed. Consequently, when the subscriber's line connected to terminals T1 and T2 is long and a voltage applied between amplifier terminals DI and DO is low, this compensating circuit can compensate the output level of a sound signal.
JP13613379A 1979-10-22 1979-10-22 Level-compensating type handset unit Pending JPS5660151A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13613379A JPS5660151A (en) 1979-10-22 1979-10-22 Level-compensating type handset unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13613379A JPS5660151A (en) 1979-10-22 1979-10-22 Level-compensating type handset unit

Publications (1)

Publication Number Publication Date
JPS5660151A true JPS5660151A (en) 1981-05-23

Family

ID=15168070

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13613379A Pending JPS5660151A (en) 1979-10-22 1979-10-22 Level-compensating type handset unit

Country Status (1)

Country Link
JP (1) JPS5660151A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5382203A (en) * 1976-12-27 1978-07-20 Northern Telecom Ltd Telephone speech circuit network

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5382203A (en) * 1976-12-27 1978-07-20 Northern Telecom Ltd Telephone speech circuit network

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