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GB673600A - Improvements in and relating to sound meters - Google Patents

Improvements in and relating to sound meters

Info

Publication number
GB673600A
GB673600A GB20336/50A GB2033650A GB673600A GB 673600 A GB673600 A GB 673600A GB 20336/50 A GB20336/50 A GB 20336/50A GB 2033650 A GB2033650 A GB 2033650A GB 673600 A GB673600 A GB 673600A
Authority
GB
United Kingdom
Prior art keywords
microphone
meter
loudspeaker
aug
amplifier
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.)
Expired
Application number
GB20336/50A
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.)
British Thomson Houston Co Ltd
Original Assignee
British Thomson Houston 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 British Thomson Houston Co Ltd filed Critical British Thomson Houston Co Ltd
Publication of GB673600A publication Critical patent/GB673600A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H3/00—Measuring characteristics of vibrations by using a detector in a fluid

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
  • Control Of Amplification And Gain Control (AREA)

Abstract

673,600. Measuring sound intensity. BRITISH THOMSON-HOUSTON CO., Ltd. Aug. 16, 1950. [Aug. 26, 1949] No. 20336/50. Class 118 (ii). A device for restoring the calibration of a sound-level meter comprising a microphone, amplifier and output meter comprises a feed-back circuit connected to the output meter and energizing a loudspeaker which is placed in a predetermined position in relation to the microphone. The gain of the amplifier is adjusted until the system is at the oscillation threshold ; alternatively, it may be adjusted to obtain a predetermined reading on the meter. The feedback circuit includes an attenuator and may also include a band-pass filter to allow the re-setting to be carried out at a definite frequency. Fig. 2 illustrates the means holding the microphone 6 and loudspeaker 1 in their predetermined, relative positions. When it is desired to use the device the microphone is inserted into the holder through the rubber ring 16.
GB20336/50A 1949-08-26 1950-08-16 Improvements in and relating to sound meters Expired GB673600A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US673600XA 1949-08-26 1949-08-26

Publications (1)

Publication Number Publication Date
GB673600A true GB673600A (en) 1952-06-11

Family

ID=22075489

Family Applications (1)

Application Number Title Priority Date Filing Date
GB20336/50A Expired GB673600A (en) 1949-08-26 1950-08-16 Improvements in and relating to sound meters

Country Status (1)

Country Link
GB (1) GB673600A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104535175A (en) * 2014-12-29 2015-04-22 上海创塔电子科技有限公司 Sound calibration device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104535175A (en) * 2014-12-29 2015-04-22 上海创塔电子科技有限公司 Sound calibration device

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