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The Digital Radio Mondiale (DRM) Consortium was formed in 1998 to create a strategy to reverse a predicted rapid decline in the number of listeners on the AM bands. The AM bands cover frequencies up to 30 MHz and have traditionally used Amplitude Modulation(AM). The Digital Radio Mondiale (DRM) consortium had an objective to create a Digital AM system as the membership included broadcasters who believed that vast numbers of people were moving to FM or other high fidelity audio systems such as DAB and satellite radio. This was contrary to what the broadcasters want as a single Long Wave or Medium Wave transmitter can cover a whole country, which is important in times of national emergencies. Short wave still has a role as a trans-national broadcasting system and for covering sparsely populated areas in large countries. A properly engineered Digital Radio Mondiale (DRM) system using frequencies in the Short Wave bands could replace a complete medium wave network. A fully enabled DRM system is similar to DAB in that the listener does not really need to know the actual frequency that they are tuned to.
The DRM Consortium later won general approval to apply the DRM technology to broadcast bands below 120 MHz that effectively made the standard an option for Band 1 and Band 2. The standard has had to be expanded (called DRM+) to deal with the 100 kHz channel spacing at VHF. Final testing was started in 2008 and the formal publication of the standard is expected by the end of 2008.
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