Wade Bequest collection of valves: full-wave rectifier radio valve

Wade Bequest collection of valves: early triode radio valve

Wade Bequest collection of valves: full-wave rectifer radio valve

Wade Bequest collection of valves: early triode radio valve

Wade Bequest collection of valves: Early triode valve by Marconi-Osram

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram, 1926

1926

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: experimental triode radio valve by Marconi-Osram

Wade Bequest collection of valves: triode radio valve

Wade Bequest collection of valves: full-wave recitifier radio valve

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: radio valve without base

Wade Bequest collection of valves: World War One German triode radio valve

1916

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: experimental triode radio valve by Marconi-Osram

1915

Wade Bequest collection of valves: early tetrode radio valve by Marconi-Osram

1916

Wade Bequest collection of valves: pentode radio valve

Wade Bequest collection of valves: experimental Catkin triode radio valve by Marconi-Osram

Wade Bequest collection of valves: four-electrode radio valve by Marconi-Osram

1920

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: early four-electrode radio valve by Marconi-Osram. With B4-3 base

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: early triode radio valve by Marconi-Osram

Wade Bequest collection of valves: experimental triode radio valve