Broadcast Television Systems Incorporated
1986 - 1995
1986 - 1995
1979 - 2003
1955 - 1989
1958 - 1978
1999
1966 - 1996
1990 - 1997
1945
1950
1944 - 1991
2001 - 2012
1950 - 2000
1961 - 1996
1948 - 1962
1957 - 1965
1968 - 1979
1967 - 1963
1964 - 1996
1950 - 2006
1904 - 1961
1946 - 1972
1955 - 1986
1948 - 1972
1979 - 1998
1986 - 1996
1997 - 2004
1948
1945 - 2000
1997 - 2004
1945 - 1948
1943 - 1948
1958 - 1970
1978 - 1984
1978 - 1999
1905 - 1964
1971 - 1982
1967 - 1974
1980 - 1987
1961 - 2001
1953 - 2009
1948 - 1969
1948 - 1992
1948 - 1992
1956 - 1983
1962 - 1996
1967 - 1992
1947 - 1966
1982 - 1988
1948 - 1953
1910 - 1954