Free Oscilloscope Web App Using a Computer Mic, Built-In Sound Library, or Your Own Files

Fuente: ERIC Institute of Education Sciences

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Bibliographic Details
Main Authors:	Ball, Edward, Ruiz, Frances, Ruiz, Michael J.
Format:	Recurso educativo Open Access
Language:	en
Published:	2017
Subjects:	Measurement Equipment Science Equipment Physics Scientific Concepts Acoustics Computer Oriented Programs Audio Equipment Accuracy Demonstrations (Educational) Music Musical Instruments
Online Access:	Acceder al recurso
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author	Ball, Edward Ruiz, Frances Ruiz, Michael J.
author_facet	Ball, Edward Ruiz, Frances Ruiz, Michael J. Ball, Edward Ruiz, Frances Ruiz, Michael J.
collection	Education Resources Information Center
contents	Free Oscilloscope Web App Using a Computer Mic, Built-In Sound Library, or Your Own Files Ball, Edward Ruiz, Frances Ruiz, Michael J. Measurement Equipment Science Equipment Physics Scientific Concepts Acoustics Computer Oriented Programs Audio Equipment Accuracy Demonstrations (Educational) Music Musical Instruments We have developed an online oscilloscope program which allows users to see waveforms by utilizing their computer microphones, selecting from our library of over 30 audio files, and opening any .mp3 or .wav file on their computers. The oscilloscope displays real-time signals against time. The oscilloscope has been calibrated so one can make accurate frequency measurements of periodic waves to within 1%. The web app is ideal for computer projection in class.
format	Recurso educativo Open Access
id	eric_EJ1143104
institution	ERIC Institute of Education Sciences
language	en
publishDate	2017
record_format	eric
spellingShingle	Free Oscilloscope Web App Using a Computer Mic, Built-In Sound Library, or Your Own Files Ball, Edward Ruiz, Frances Ruiz, Michael J. Measurement Equipment Science Equipment Physics Scientific Concepts Acoustics Computer Oriented Programs Audio Equipment Accuracy Demonstrations (Educational) Music Musical Instruments Free Oscilloscope Web App Using a Computer Mic, Built-In Sound Library, or Your Own Files Ball, Edward Ruiz, Frances Ruiz, Michael J. Measurement Equipment Science Equipment Physics Scientific Concepts Acoustics Computer Oriented Programs Audio Equipment Accuracy Demonstrations (Educational) Music Musical Instruments We have developed an online oscilloscope program which allows users to see waveforms by utilizing their computer microphones, selecting from our library of over 30 audio files, and opening any .mp3 or .wav file on their computers. The oscilloscope displays real-time signals against time. The oscilloscope has been calibrated so one can make accurate frequency measurements of periodic waves to within 1%. The web app is ideal for computer projection in class.
title	Free Oscilloscope Web App Using a Computer Mic, Built-In Sound Library, or Your Own Files
topic	Measurement Equipment Science Equipment Physics Scientific Concepts Acoustics Computer Oriented Programs Audio Equipment Accuracy Demonstrations (Educational) Music Musical Instruments
url	https://eric.ed.gov/?id=EJ1143104

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// Anecdotal testing Today and Yesterday seems to indicate destroy() // is called by the garbage collector and everything is good. // Something to keep in mind though. return 0; } /** * Write function that is called when session data is to be saved. * * @param string $sessId The current session ID * @param string $data The session data to write * * @return bool */ public function write($sessId, $data): bool { if ($this->writesDisabled) { return true; } return $this->saveSession($sessId, $data); } /** * A function that is called internally when session data is to be saved. * * @param string $sessId The current session ID * @param string $data The session data to write * * @return bool */ abstract protected function saveSession($sessId, $data): bool; }

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