Нужно перевести текст, только не через переводчик (промт) TELEPHONE COMMUNICATION. One of the most…

Нужно перевести текст, только не через переводчик (промт) TELEPHONE COMMUNICATION. One of the most important kinds of wired communication is telephony. It is the transmission of speech over a considerable distance by means of electric current. Telephone set includes a transmitter, and an electric network in addition to receiver. The transmitter or microphone consists of a diaphragm, carbon chamber with carbon granules and insulating spacer and conductor. The electric current passes through the diaphragm and carbon granules. When we speak we produce sound waves which make the diaphragm vibrate. The diaphragm in its turn pushes the carbon granules which makes more or fewer contacts and decreases or increases the resistance. Thus the waves of electric current vary depending on the sounds we produce and pass along the line and finally reach the receiver. The receiver consists of electromagnet coils, a steel magnet and a diaphragm. A variable current passing through the magnet's coil makes the diaphragm vibrate. The frequency of these oscillations is the same as that of the transmitter. Therefore the receiver reproduces the same sounds as are spoken into the microphone. The telephone was designed in 1875 by Alexander Bell. Later on the development of the telephone changed its construction, it became more complex. Auxiliary elements were used in the circuit to provide better transmission of speech. Further on the development improved the switching system. Now very complex telephone constructions are used and a new kind of telephone appeared — radiotelephone.