The CV4086 is the flying lead version of the M8195 = CV4085 that is the special quality version of the Mullard EF86 early stage audio pre-amplifier valve. The CV specification used the CV2901 as the prototype.
Mullard recommend that the EF86 is fitted into an anti-microphonic base. This usually means a base where the fixing flange is a synthetic rubber structure. In this valve the flying leads are designed for direct soldering into a circuit. A rigid fixing used with valves of high reliability.
The KB/D identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the D identifies the maker as Mullard Radio Valve Co., Mitcham.
The ripples in the soft glass envelope blur the inner structures.
The leads are sealed directly into the hard glass base in the same way that pins would be.
The thin glass tube envelope is 20 mm in diameter and excluding the B9A base pins, is 48 mm tall.
Reference: Data-sheet. Type CV4086 was first introduced in 1959. See also1959 adverts.
