Of the 37 new transmitters, 35 are medium wave and 2 are shortwave transmitters. Both SW transmitters are for international service and are broadcasting in pure DRM. Out of the 35 MW transmitters, 2 are broadcasting in pure DRM, carrying two audio services in digital; the other 33 transmitters are working in simulcast mode. Out of these, 25 MW transmitters are working for 1 hour in pure DRM every day (Monday to Saturday). The transmission powers of these 35 transmitters are: 1000 kW (two), 300 kW (six), 200 kW (10), 100 kW (11) and 20 kW (six); two SW transmitters are 500 kW and 250 kW each.
AIR is now in the process of launching phase-II of the DRM project by offering full features and services from these DRM transmitters and further improving service quality. When Phase-II is complete, the full-featured DRM services will be available to the audience and a public information campaign will be initiated to inform the Indian citizens of the completely new and future- oriented DRM radio platform and its many benefits. During phase-II, most transmitters will carry a new DRM signal while still maintaining the analog AM transmission to support existing analog receivers (the ‘simulcast’ mode of DRM) – with all-digital transmissions available during certain times of the day.
Phase-III, as presented by AIR, will eventually culminate in the complete transition of radio services to the digital DRM platform, further improving the number and quality of radio services and extra features for the listeners, while also saving tremendous amounts of transmission power every year, according to the same article.
Source & Credit:http://www.radiomagonline.com/around-the-world/0020/air-launching-drm-conversion-phase-ii/38740