The M8248 is a special quality UHF triode for use as a grounded grid amplifier. The construction is based around the frame grid that is significantly wider than the anode plate.
Winding under tension stretches the wire and ensures that all the wires are in the exact same plane. Thus the cathode and anode can be sited very close to the grid.
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 dark small anode with broad bright straps joining the two halves.
A closer view of the frame grid. The wire is very thin and wound at half breaking strain. The bars top and bottom are essential to maintain the tension in the wire.
The reverse carries the CV5311 designation.
The thin glass tube envelope is 18 mm in diameter, and excluding the B7G base pins, is 43 mm tall.
Reference: Data-sheet. Type M8248 was first introduced in 1962. See also1962 adverts.
