Documentation of techniques, exchange of experiences, reports. In radio, analog transmission using AM, FM is still very popular but is on the way to be replaced by DAB/DAB+ digital radio and possibly also DRM/DRM+. Local community broadcasters cannot afford the costs of DAB+ operators existing for public or commercial broadcasters. Transmitting using these technologies usually requires complex and
costly equipment out of reach of local broadcasters. However, since the democratization of software defined radio (SDR) technology, a new field of possibilities opens for transmission. The technique was very experimental at the beginning. This has been the first motivation, in 2009, for the creation of opendigitalradio.org website to document the experimentation, open source developments around this technology. Since then, this has attracted more and more interest from the community and first low power, ultra local experimentations have been made. We now start to see real local transmission based on CRC mmbTools and Ettus USRP, together with high power amplifier/mask filter.
