[go: up one dir, main page]

JPS56154835A - Noise reduction circuit - Google Patents

Noise reduction circuit

Info

Publication number
JPS56154835A
JPS56154835A JP5769080A JP5769080A JPS56154835A JP S56154835 A JPS56154835 A JP S56154835A JP 5769080 A JP5769080 A JP 5769080A JP 5769080 A JP5769080 A JP 5769080A JP S56154835 A JPS56154835 A JP S56154835A
Authority
JP
Japan
Prior art keywords
amplifier
gain
emphasis
noise reduction
input
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
JP5769080A
Other languages
Japanese (ja)
Other versions
JPS6145902B2 (en
Inventor
Kenzo Akagiri
Masayuki Katakura
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.)
Sony Corp
Original Assignee
Sony Corp
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 Sony Corp filed Critical Sony Corp
Priority to JP5769080A priority Critical patent/JPS56154835A/en
Publication of JPS56154835A publication Critical patent/JPS56154835A/en
Publication of JPS6145902B2 publication Critical patent/JPS6145902B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G9/00—Combinations of two or more types of control, e.g. gain control and tone control
    • H03G9/02—Combinations of two or more types of control, e.g. gain control and tone control in untuned amplifiers
    • H03G9/025—Combinations of two or more types of control, e.g. gain control and tone control in untuned amplifiers frequency-dependent volume compression or expansion, e.g. multiple-band systems

Landscapes

  • Signal Processing Not Specific To The Method Of Recording And Reproducing (AREA)
  • Reduction Or Emphasis Of Bandwidth Of Signals (AREA)

Abstract

PURPOSE:To increase low-frequency noise reduction effect by providing a variable gain amplifier itself with frequency characteristics that cancel influences of those of filters for pre-emphasis and de-emphasis when an input level is small. CONSTITUTION:Between input terminal 11 and output terminal 12, HPF13 for pre- emphasis and gain control amplifier 14 are interposed in series. Then, part of the output of amplifier 14 is sent to control terminal 16 of amplifier 14 via control circuit 15. This amplifier 14 decreases in gain as the input level rises. The gain increases as the input signal level drops, but the gain is limited to a certain value when the input level becomes extremely small. So that the gain of the noise reduction circuit at this time varies with the frequency through filter circuit 13 for emphasis, amplifier 14 is provided with a correcting filter circuit. Thus, the noise reduction effect of low frequencies is increased.
JP5769080A 1980-04-30 1980-04-30 Noise reduction circuit Granted JPS56154835A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5769080A JPS56154835A (en) 1980-04-30 1980-04-30 Noise reduction circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5769080A JPS56154835A (en) 1980-04-30 1980-04-30 Noise reduction circuit

Publications (2)

Publication Number Publication Date
JPS56154835A true JPS56154835A (en) 1981-11-30
JPS6145902B2 JPS6145902B2 (en) 1986-10-11

Family

ID=13062933

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5769080A Granted JPS56154835A (en) 1980-04-30 1980-04-30 Noise reduction circuit

Country Status (1)

Country Link
JP (1) JPS56154835A (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52111308A (en) * 1976-03-16 1977-09-19 Pioneer Electronic Corp Signal compressing and expanding device
JPS5351909A (en) * 1976-10-21 1978-05-11 Toshiba Corp Noise reduction system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52111308A (en) * 1976-03-16 1977-09-19 Pioneer Electronic Corp Signal compressing and expanding device
JPS5351909A (en) * 1976-10-21 1978-05-11 Toshiba Corp Noise reduction system

Also Published As

Publication number Publication date
JPS6145902B2 (en) 1986-10-11

Similar Documents

Publication Publication Date Title
JPS56152337A (en) Noise reduction system
JPS5744338A (en) Noise reduction device
JPS5717241A (en) Dynamic emphasis circuit
JPS5746517A (en) Noise reduction circuit
JPS56106433A (en) Noise reducing circuit
JPS5752239A (en) Noise reducing circuit
JPS56154835A (en) Noise reduction circuit
JPS5752240A (en) Noise reducing circuit
JPS5642413A (en) Sound-field singla correcting device
JPS56103523A (en) Active filter circuit
JPS5664508A (en) Low-band compensating circuit
JPS56107648A (en) Noise reduction circuit
JPS56106431A (en) Transistor of reduced carrier ssb signal
JPS5478053A (en) Filter circuit
SU792556A1 (en) Active filter
JPS5443448A (en) Compressor
JPS54126445A (en) Notch filter
JPS57188162A (en) Signal receiver
JPS56132009A (en) Tone control device
JPS54152414A (en) Squelch system of fm mobile radio equipment
JPS6455971A (en) Noise reducing circuit
JPS5459055A (en) Variable attenuator to signals at specified frequency band
JPS5745708A (en) Amplifying circuit
JPS54157018A (en) Fm receiver
JPS56156096A (en) Speaker device