This version of the first thermionic device for communication use a bayonet base as does Fleming. Our two other Oscillation Valves use the candelabra base.
To protect the electron stream from external electric fields some of Fleming's valves had a copper gauze screen as does this exhibit.
The flat anode plate can just be seen through the gauze.
The gauze obscures the details but one can make out the pinch on the left and the anode connection passing to the side wire.
The rectangular anode appears to be made of copper but was probably a silvery metal that is reflecting the colour of the gauze.
The outer screen is soldered along both the seam and to the base.
The wide glass tube envelope is 26 mm in diameter, and including the base is 114 mm tall.
References: 1047 & Observation. Type Fleming was first introduced in 1904. See also1904 adverts.
