120 volts from the AC line is fused and then passes through a half wave voltage doubler consisting of 2 redtifier diodes and a capacitor generating a voltage of around 330-340VDC. This is then used to charge a capacitor. Across the capacitor is a 1 megaohm resistor to bleed the charge off when power is disconnected. Also across the capacitor is a Xenon strobe tube. Another .68 microfarad capacitor charges throuhg a 1.8 megaohm resistor until it reaches the breakover voltage of a neon lamp. The neon lamp then dumps the charge into the gate of a silicon controlled rectifier which is shunted by another resistor. This turns the SCR on which takes the rest of the charge and dumps it into the primary of a trigger transformer. This voltage is then stepped up to around 3000kV at a low current which is applied to the outer envelope of the Xenon tube. This ionizes the xenon gas in the tube, forming a conductive channel which quickly discharges the main storage capacitor, resulting in a bright flash. The process repeats until power is removed.
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