Decoding DTMF Tones

Students will use a wireless sound sensor and the fast Fourier Transform (FFT) display of the data collection software to analyze the tones produced when dialing a phone. They will uncover the pattern of these dual frequency tones showing the first frequency gives the row of the key on the numeric keypad and the second frequency gives the column. From this information they can determine what key is pressed without seeing it.

Grade Level: High School

Subject: Physics

Student Files

Decoding DTMF Tones 81.81 KB
Decoding DTMF Tones 121.32 KB

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Featured Equipment

Wireless Sound Sensor

Wireless Sound Sensor

The Wireless Sound Sensor measures sound wave forms and sound level in one compact and portable sensor.

Physics Starter Lab Station

Physics Starter Lab Station

This starter Lab Station includes the wireless motion, force, current and voltage sensors used to perform some of the key lab activities from the Physics Lab Station Investigations manual.

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