You might have wondered how your mobile phone sends your voice to another phone, Does it record? or something else is hidden behind. Its all done by Microphone, generally known as Mic. It does not record your voice & store them, there is not any electronics or digital components in it. Before you get to know how does a MIC works you should know what it is. See also
What Is A Microphone?
A microphone(mic) is a device which converts acoustical (sound) energy first into mechanical & latter in electrical, the electrical signal thus obtained is transmitted through any tranmission medium (cables, optical fibres or microwaves in case of mobile telephony).
How Does It works?
You might have alredy understood that, microphone is simply a 'transducer' converting sound energy to electrical energy. Main componets that make it happen are diaphragm, membrane, or other mechanical element in them that vibrates sympathetically in response to the arriving acoustic. As we all know voice are result of vibrations caused in air when we speak something, these vibrations are used in this process. Generally when we speak sound waves of our speech impinges on a mechanical system capable of detecting vibrations, which is further attached to a diaphargm. The diaphragm moves in and out as per vibrations which causes change in voltage levels & thus are recorded as variable electrical signal. The mechanical system used vary for different microphone. One of which is explained as:
Carbon microphone:
A carbon microphone used a membrane or simply a box containing carbon granules in it, the resistivity of the granules depend on the density with which they are packed. The box is made flexible from one side & attached to a magnetic diaphragm on the other, which is further attached to a coil or a stationary magnet. Main working starts now, when 'sound' or 'acoustic' waves impinges on the flexible side of the box granules present inside it expands & compress, this subjected 'expansion & compression' makes the resistivity variable. On the same time the diaphragm attached other side becomes active & 'move in & out' so as does the coil. The movement of the coil in the fixed magnetic field generates an electrical signal in the coil that "corresponds" to the sound that created it. The signal may then be sent over any communication media.
Post a Comment