JPS55151807A - Acoustic device in mobile - Google Patents

Acoustic device in mobile

Info

Publication number
JPS55151807A
JPS55151807A JP5986579A JP5986579A JPS55151807A JP S55151807 A JPS55151807 A JP S55151807A JP 5986579 A JP5986579 A JP 5986579A JP 5986579 A JP5986579 A JP 5986579A JP S55151807 A JPS55151807 A JP S55151807A
Authority
JP
Japan
Prior art keywords
noise
volume
point
exceeds
reference voltage
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
JP5986579A
Other languages
Japanese (ja)
Inventor
Seiichiro Hirata
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.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric 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 Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP5986579A priority Critical patent/JPS55151807A/en
Publication of JPS55151807A publication Critical patent/JPS55151807A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G3/00—Gain control in amplifiers or frequency changers
    • H03G3/20—Automatic control
    • H03G3/30—Automatic control in amplifiers having semiconductor devices
    • H03G3/32—Automatic control in amplifiers having semiconductor devices the control being dependent upon ambient noise level or sound level

Landscapes

  • Control Of Amplification And Gain Control (AREA)

Abstract

PURPOSE:To ensure the automatic control for the sound volume of the car radio or the like in case the noise exceeds the fixed level, by giving the amplifying detection to the volume of the noise for comparison with the DC reference voltage and then giving the amplification or attenuation to the output of the aural preamplifier or the like in case the noise volume exceeds the reference level. CONSTITUTION:The volume of the noise collected by microphone 5 attached to part of car body 10 is amplified through low frequency amplifier 6 for detection 7 and then compared with the DC reference voltage at point D via comparator 8 to deliver the detected DC to point C. Thus the electronic volume or electronic attenuator 2 is driven by the DC delivered to point C to give amplification or attenuation to the output signal of receiving part or aural preamplifier 1. And the signal at point A of amplifier 1 is amplified in case the noise caught at microphone 5 exceeds the DC reference voltage level. As a result, the sound volume of car radio 11 or the like can be controlled automatically when the external noise exceeds the fixed level.
JP5986579A 1979-05-15 1979-05-15 Acoustic device in mobile Pending JPS55151807A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5986579A JPS55151807A (en) 1979-05-15 1979-05-15 Acoustic device in mobile

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5986579A JPS55151807A (en) 1979-05-15 1979-05-15 Acoustic device in mobile

Publications (1)

Publication Number Publication Date
JPS55151807A true JPS55151807A (en) 1980-11-26

Family

ID=13125489

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5986579A Pending JPS55151807A (en) 1979-05-15 1979-05-15 Acoustic device in mobile

Country Status (1)

Country Link
JP (1) JPS55151807A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63256006A (en) * 1987-04-13 1988-10-24 Kenwood Corp Automatic sound volume adjusting device
US5892834A (en) * 1997-06-30 1999-04-06 Ford Motor Company Audio level dynamic range compression

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63256006A (en) * 1987-04-13 1988-10-24 Kenwood Corp Automatic sound volume adjusting device
US5892834A (en) * 1997-06-30 1999-04-06 Ford Motor Company Audio level dynamic range compression

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