5AM8

Duodiode and Sharp-Cutoff Pentode Multi-Unit Tube, featuring a 4.7V heater filament. It combines two independent signal rectifier diodes with a high-gain pentode section to act as a centralized AM detector, AVC rectifier, and video/audio pre-amplifier inside television chassis, housed in a standard 9-pin miniature glass envelope (Noval, T-6.5 bulb).