Sharp-Cutoff Pentode
The Western Electric 404A Vacuum tube is a miniature pentode of the unipotential cathode type. It is
designed for use in high gain amplifiers at high and ultra high frequencies. They require a miniature
9 pin contact socket.
Electrical Data:
Heater Voltage ................................ 6.3 V
Heater Current ................................ 0.6 A
Preferred Substitutes ..... 5847, CV3905.