Complex sentence: Skues left Radio 1 in 1974 and was appointed director of Radio Hallam (now Hallam FM) and by 1980 was the longest serving programme director in music radio.
Split into simpler sentences: Skues left Radio 1 in 1974 and was appointed director of Radio Hallam (now Hallam FM). By 1980 was the longest serving programme director in music radio.