Season 1 BBC One , 1965 - 1968 Season 2 BBC One , 1968 Season 3 BBC One , 1969 Season 4 BBC One , 1969 - 1970 Season 5 BBC One , 1970 Season 6 BBC One , 1971 Season 7 BBC One , 1972 Season 8 BBC One , 1972 Season 9 BBC One , 1973 Season 10 BBC One , 1973 Season 11 BBC One , 1974 - 1976 Season 12 BBC One , 1976 Season 13 BBC One , 1977 Season 14 BBC One , 1978 Season 15 BBC One , 1980 Season 16 BBC One , 1984 Season 17 BBC One , 1985 Season 18 BBC One , 1988 Season 19 BBC One , 1990 Season 20 BBC One , 1992 Season 21 BBC One , 1992 Season 22 BBC One , 1993
, 1965 - 1968