From the mid-1950s onwards Sadie made many broadcasts for BBC Radio, appearing most frequently on the Third Programme and its successor, Radio 3. He devised a number of programmes in which he wrote the scripts and selected the music and was also a frequent contributor to 'Music Magazine' and 'Record Review', reviewing the latest recordings and recently published books on music.
In the 1980s he acted as a music consultant to the television series 'Man and Music' broadcast on Channel 4.