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Voltage Stabilizers Using Gas Diodes

Variations in line voltage and changes in the load current will cause the direct voltage output of a rectifier to vary. The cold-cathode gas diode is used to stabilize this output voltage as shown in Fig. 15. The circuit is designed so that the tube is operated over a portion of the characteristic curve of Fig. 7, where the voltage varies but little with changes in current. If the input voltage rises, the cold-cathode gas diode draws a larger current, an increased voltage drop occurs across the series resistor R, and this absorbs the voltage rise, If the input voltage falls, the gas diode draws less current, less voltage drop occurs across resistor R, and the voltage across load resistor RL remains essentially the same. A stabilizing action also occurs if the load current supplied to RL varies.


Last Update: 2011-05-18