telephone links

A microphone is a device that transforms sound pressure into electrical energy. In most types of microphone, the sound pressure acts upon a thin plate or diaphragm, setting it into vibration, and this mechanical motion is then utilised to produce electrical effect..

Communication satellites are normally geostationary satellites. They have devices called transponder which receive signals from an earth station and transmit them in different directions. The signals in the form of electromagnetic radiation are transmitted from the earth station and these signals a..

) use a similar mechanism. In the case of intercontinental telecommunication, two or more satellites are linked together. High frequency radio and submarine cable systems have been widely used for long- distance overseas telecommunications. The high frequency band from 3 MHz to 30 MHz has..

. Telephone and telegraph wires; audio, video, and radio cables; and the myriad nerve fibers in our bodies are all transmission lines. The interconnections of all electric circuits are transmission lines, and in a broad sense waveguides and optical fibers, and even radio links m..