Dibble was best known as the senior newsreader for ABC-TV, beginning with the first televised news bulletin on ABN-2 Sydney on 5 November 1956. He reported the biggest news stories of the period, including the Soviet intervention in the Hungarian Revolution (in his very first bulletin; the events in Hungary caused the scheduled commencement of the ABC-TV news service to be brought forward), the assassination of John F. Kennedy (1963), the disappearance of Prime Minister Harold Holt (1967), the Apollo 11 Moon landing (1969), the destruction of Darwin by Cyclone Tracy (1974), and the dismissal of the Whitlam government (1975).