The Sound Sensor BT80i is a microphone followed by an amplifier. The microphone is mounted at the end of the plastic tube and connected to the amplifier with the 3.5 mm jack connector. The sensor measures variations in air pressure in the measurement range between -45 and 45 Pa caused by a sound wave. Because of the high sensitivity, the sensor is very much suited to detect short pressure pulses. This offers the possibility to measure the speed of sound.
The sound sources that can be used with the microphone are tuning forks, electronic keyboards, and musical instruments. You may also investigate a human voice or a whistle.
Within a certain range, the sensor can also be used for dB-measurements, a suitable calibration is present in the Coach software.
The microphone of the Sound sensor can be replaced by the CMA Stethoscope to record the heart rate and the echoes of the beat in the circulation. The stethoscope is not delivered with the sensor and has to be purchased separately (CMA article BT80ST)
The Sound sensor can be directly connected to the analog BT inputs of the CMA interfaces. The sensor cable BT - IEEE1394 needed to connect the sensor to an interface is not supplied with the sensor and has to be purchased separately (CMA article BTsc_1).
The sound sensor can be used in a variety of experiments with sound waves such as:
• measure wave patterns (frequency and amplitude of sound),
• demonstrate beat patterns,
• compare waveforms from various musical instruments,
• measure the speed of sound through air and other materials,
• display the Fourier transform (FFT) of a sound.
The Sound sensor can be directly connected to analog BT inputs of the CMA interfaces.Attention:
The sensor cable BT - IEEE1394 needed to connect the sensor to an interface is not
supplied with the sensor and has to be purchased separately (CMA Art. Nr BTsc_1).
Technical specifications of the sensor are described in its User's guide