The CV3885 (Commercially the EF40) is described as a voltage amplifying pentode, primarily intended for use in high gain RC coupled AF voltage amplifier stages.
The Mullard logo and Type designation. This example was an import and carries the pejorative term Foreign as the local industry aimed at discouraging consumers to buy other than British made.
The three wire grids can be seen through the hole in the outer mesh screen. The anode consists of a small plate either side of the cathode and connected by an integral strap.
The thin glass tube envelope is 20 mm in diameter and, excluding the B8A base pins, is 53 mm tall.
