The 832A is a VHF transmitting beam tetrode. The American design uses a pair of valve sections within the envelope and required external neutralisation to remain stable, ie not produce parasitic oscillations. The European pattern used a two sided cathode and internal neutralisation. SeeQQV03-20A.
The Adzam brand - chosen when they had to stop using Mazda.
The grids are wound on copper supports and below the black anode can be seen the bright beam plate. The heater wires are welded to the horizontal bus bars.
A view of the base. The black rectangle connected to the control grid support acts as both heat radiator and screen.
The wide glass tube envelope is 54 mm in diameter, and excluding the B7A base pins is 57 mm tall.
Reference: Data-sheet. Type 832A was first introduced in 1943. See also1943 adverts.
