Season 1 BBC Two , 1970 Season 2 BBC Two , 1971 - 1972 Season 3 BBC Two , 1973 Season 4 BBC Two , 1973 - 1974 Season 5 BBC Two , 1975 Season 6 BBC Two , 1976 Season 7 BBC Two , 1977 Season 8 BBC Two , 1980 Season 9 London Weekend Television , 1981 - 1982
, 1970