The 6J5G is a single triode is housed within a glass envelope. The electrode assembly is formed on a glass pinch in the traditional style. The anode plates are formed to leave an oval cavity for the grid and cathode.
STCF 101 - a depot or inspection site?
The old stores code of 10E/348 is on the base cap together with the RAF up arrow and the commercial Type designation.
The classic envelope is 38 mm in maximum diameter and excluding the IO base pins the valve is 86 mm long.
References: Data-sheet, 1040 & 1043. Type 6J5G was first introduced in 1936. See also1936 adverts.
