Television and radio are the oldest communication means. They were created in the middle and at the beginning of 20 century correspondingly. Since their invention many years passed, many modern communication means were created, but still radio and television are in demand. Even Internet could not replace these two inventions. Television is widely spread telecommunication mean for transmitting and receiving color frame elements by means of deflection, followed by sound. Radio - is a variation of wireless connections in which freely circulating radio waves serve as signal carriers. Signals are transmitted by modulation of electromagnetic waves with frequencies below visible light. Information is carried by steady changing attributes of the radiated waves, such as amplitude, frequency, phase, or pulse width.
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