Sunday, August 23, 2009
Main parts of Telephone
A telephone has two main parts to it, one is the 'Transmitter' and the other is the 'Receiver'. The transmitter is placed behind the mouthpiece of the instrument. It has an eardrum which is thin, round metal disc called a diaphragm. This diaphragm vibrates when the sound waves strike it. This vibration takes place at different speed levels. This depends on the air pressure caused by the voice. Behind this metal disk there is a container filled with tiny grains of carbon. Subsequently, the diaphragm presses on these carbon grains. This pressure varies as the diaphragm vibrates, due to sound waves. The louder the sound the harder is the diaphragm pushed. The receiver is known as an electric mouth. In the receiver there is a diaphragm located which has two magnets located at the edge of it. One magnet is an electromagnet which consists of an electric wired coil which is wound around it. If the vocal levels are high, the electric force passed through this wire is stronger and attracts the diaphragm towards it. The diaphragm vibrates depending on the vocal levels. Since the diaphragm keeps moving in and out it pushes the air around it, this air sets up the sound waves. These waves are what strike the ear of the listener.