The American Type 84 full wave rectifier is identical to the 6Z4.
The common cathode runs vertically through the two anodes that are stacked one upon the other. Each anode is identical and not symmetrical, thus allowing for the connections to be separated. Each anode is held by the support and a tab through the mica sheets.
The 84 within a circle on the glass.
The front to back dimension is small - about 3 mm. The absence of the gettering is due to the failure of the vacuum. There is a quantity of white powder in the envelope.
The stacked construction.
The classic envelope is 38 mm in diameter and, excluding the UX5 base pins, is 86 mm tall.
References: Data-sheet, 1040 & 1043. Type 84 was first introduced in 1937. See also1937 adverts.
