All Available Season All Season Specials Feb, 1968 2 episodes 0.0 Season 1 Sep, 1971 7 episodes 7.1 Season 2 Sep, 1972 8 episodes 7.2 Season 3 Sep, 1973 8 episodes 7.4 Season 4 Sep, 1974 6 episodes 7.4 Season 5 Sep, 1975 6 episodes 6.8 Season 6 Oct, 1976 3 episodes 7.1 Season 7 Nov, 1977 5 episodes 7.2 Season 8 Feb, 1989 4 episodes 6.6 Season 9 Nov, 1989 6 episodes 6.8 Season 10 Dec, 1990 14 episodes 6.8