AC042 Mullard old logo 2P PA20 pair output triode early type tested pair tubes valves

Description

The Mullard AC042 is a low impedance triode

Introduced in 1937 the AC042 is capable of giving 3.5 watts hence suotable for sensitive speakers

Nice pair of  Mullard  ST Fat shape with AC042 on glass.

The filament works at 2 Volts

Anode 300 Volts

Anode dissipation 50mA

Grid -38

mA/V 5

Both valves AC042 tested mint at 45mA and 44mA 100% emission.