
Mazda QP.240 battery double output pentode valve (McVitie Weston valve collection), 1935
1935
1935
1910-1960
1906-1972
1981
1922
circa 1925
1990-1995
1996
1985-1995
1996
1986-1996
circa 1930; 1920
1947
2020
1986-1996
1980
1923
1990-1995
1986-1996
1922
1986-1996
1986-1996
1986-1996
1986-1996
1922
1977
1932
1912
circa 1925; circa 1925
1992-1996
1940-1960
1901
1923-07
1928
1937
1950-1952
1932
1922
1835-1960
1952
1951
1957
1950
1951
1953
1957
1939-03-28