DuckCorp Dico

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1.                 From The Free On-line Dictionary of Computing (19 January 2023):
                   
   
   
                   
                     
   Astra Digital Radio
   ADR
      <audio> Digital Radio over satellite, compatible with analog
      television transmissions.  Alternatively the normal TV
      subcarriers can be modulated by a MPEG-1 Layer-2 48 kHz 192
      kbps signal.  Quality is better than analog carriers and only
      needs half the bandwidth (analog stereo = 2 carrier, digital
      stereo = 1 carrier).  Quality is limited and the data rate
      can't be increased.
      (2001-12-13)