Often people wonder what the difference is between AM and FM. The only difference is technical. AM and FM refer to a technical method used to superimpose sounds, such as music and speech, on to a radio.
AM (amplitude modulation) is a system of radio transmission in which the carrier wave is modulated by changing its amplitude. The operating frequency is expressed in kilohertz (kHz).
FM (frequency modulation) is a broadcasting mode in the VHF (very high frequency) broadcasting bands. It provides a high quality analogue signal, and is relatively free from static, in which the frequency of the transmitted wave is modulated or varied in accordance with the amplitude and pitch of the signal. The operating frequency is expressed in megahertz (MHz).
Digital radio is the next generation of radio. It is a revolutionary audio broadcasting technology, which dramatically improves sound quality, and will enable you to receive value added radio services for free.
Digital is a new way of transmitting and receiving radio signals. It turns sound and data into digital signals at the transmission end. These are broadcast over the airwaves and a digital radio receiver decodes the signal into CD quality sound with data enhancements including text information and graphics. Listeners will need to buy a digital radio receiver to tune in, as existing analogue AM/FM receivers cannot tune digital. More at www.digitalradioplus.com.au.