AM was the dominant method of broadcasting during the first four-fifths of the 20th century and remains widely used into the 21st.
DXer's Blog full with DX, Shortwave, Mediumwave, Electronics, South Asian DX, Web info. Shortwave, SW listening (DXing), Radio Amateurs Discover the spread long distances shorter and Marconi takes the world by surprise. It also addresses the types of receivers and antennas, you should use, and an introduction to the spread of the signal.
Tuesday, October 23, 2007
AM broadcasting :: Radio @ DXing Info
Uses of radio - Maritime, telegraph to AM
Invention of Radio
Radio is the wireless transmission of signals, by modulation of electromagnetic waves with frequencies below those of visible light.
Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space. It does not require a medium of transport. Information is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude or their frequency. When radio waves pass an electrical conductor, the oscillating fields induce an alternating current in the conductor. This can be detected and transformed into sound or other signals that carry information.