§  73.403   Digital audio broadcasting service requirements.

   (a) Broadcast radio stations using IBOC must transmit at least one
   over-the-air digital audio programming stream at no direct charge to
   listeners. In addition, a broadcast radio station must simulcast its
   analog audio programming on one of its digital audio programming
   streams. The DAB audio programming stream that is provided pursuant to
   this paragraph must be at least comparable in sound quality to the
   analog programming service currently provided to listeners.

   (b) Emergency information. The emergency information requirements found
   in § 73.1250 shall apply to all free DAB programming streams.