Make strobe light with NE555

The strobe light circuit made with NE555 is shown in Figure 3-16. It consists of three major parts: power circuit, oscillation circuit , and flash circuit
. The 220V alternating current is rectified
    by VDI and directly charges the capacitor C3. The resistor Rl has the dual functions of limiting the current and preventing the glow discharge of the flash tube. The other channel of 220V AC power outputs about 12V stable DC voltage through c5 step-down current limiting, VD2, VD3 rectification and voltage stabilization and cl filtering for power consumption of the oscillation circuit . The NE555 time base circuit forms a self-excited multivibrator, and pin 3 outputs square wave pulses. After power is turned on, the indicator LED2 can be seen flashing one after another. If the switch SB is pressed, the contact kl of the relay K will suck and release. When kl absorbs the stage, the charge stored in C4 is rapidly discharged through the primary of transformer T, and its secondary coil induces a high voltage of tens of thousands of volts, triggering the flash tube H to emit a strong flash. When the contact is disconnected, C3 replenishes energy for C4 through R7 and R8. Therefore, if you hold down SB , the lamp H will emit bursts of flash continuously. Adjust the potentiometer RP, the flash frequency can be changed between 1 ~ 10Hz .