Classification: Diode Heater voltage: 2.5 Max voltage: 5000 | Cathode type: Directly heated Heater current: 5 A Max current: 250 mA | |
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The 866 is a mercury vapor half-wave rectifier intended for high-voltage applications. The voltage drop is approximately 15 volts up to 150 Hz. To avoid unwanted shorts the tube must be operated in a vertical position and the filament preheated for at least 30 seconds before applying the plate voltage.
Contents
Construction
Structurally, it consists of a linear electrode arrangement; a cup shaped anode with top cap and a cylindrical cathode. The socket is a medium 4 pin bayonet UX-4 and the glass envelope is ST-19. The 2.5 volt/ 5 Amp filament is connected to pins 1 and 4.
Operation
Under normal operating conditions the tube glows blue and mercury droplets are visible.
References
866A Wikipedia(Text) CC BY-SA