Mobile phone microphone also known as mouthpiece is the one that intercepts the voice to transmit to other mobile phone users. Without it or a defective one will result that the other user on a phone cannot hear the one with a defective microphone on its mobile phone handsets.
A technical term of a microphone is a device used to convert sounds into electrical signal.
A microphone is made of an electrical magnetic wire shaped into a round coil with a magnet metal surrounds it, the mechanical vibration generated by it will then produce an electrical voltage signal.
Checking the microphone is also been so easy, Just set the analog or digital multi-tester to x1 resistance value then attach both test probe to its terminal. A good sign of a working microphone tends to have a reading while the busted one will have no reading. In some other cases types of microphones may only have a reading to the range of x10 for some high resistance value.