Submerged repeater amplifier, 1967
1967
1967
1956
1954
1953
1955
2017
1923-1925
circa 1939
1910-1920
circa 1943
1952
1938
1965; 1965
circa 1949
1956
1954-1960
1931
1935
1972
1961
1952
1938
circa 1963
1900-1930
circa 1931
1963
1936
1960
1977
circa 1928
1952
1938
1999
1960
1970-1971
1931-1940
1956
1968
1952
1919
1953-1954
1966