
BBC L1 lip microphone, 1937-1960
1937-1960
1937-1960
1964-1988
1964-1988
1967
1922-1924
1967
1923
1964-1988
1964-1988
1964-1988
2011
circa 1954
1970
circa 1931
1971
1985
1948-1955
1961
August 1960
12 October 1951
August 1936
1933
1958
1950-60
1935
1931
1980
1961
1990-1994
1972
circa 1960
Unknown
1950-60
circa 1961