Season 1 CBS , 1965 - 1972 Season 2 CBS , 1973 - 1979 Season 3 CBS , 1980 - 1983 Season 4 CBS , 1984 - 1991 Season 5 CBS , 1992 - 2011 Season 6 CBS , 1988 - 1989 Season 7 CBS , 1969 - 1980