For 1953, a new range of B7G valves for battery receivers was introduced by Mullard. This range differed from previous battery valves by having a filament current consumption of 25mA - which was 50% less than the previous devices. The four types were: -
DK96: A heptode designed as a self oscillating frequency changer with the first & second grids forming the oscillator section, the third grid the detector .
DF96: A variable-mu HF pentode designed as an LF amplifier.
DAF96: A short-grid base pentode designed for AF amplification combined with a single diode designed as a detector.
DL96: An output pentode designed with two filament sections which may be series or parallel connected.