When the circuit is connected to the power supply, the 12V voltage is divided by the resistor Rl, R2 and the flash SD filament, so that the PNP type triode BGl (9012) base potential is lower than the power supply voltage (about 10.5V), the BGl saturation is switched on, and then the 12V voltage is divided by the BGl e-c pole, R3 and R4. NPN type triode BG2; The (9013) base provides bias so that the BG2 is also saturated and the relay is electrically operated. The normally open contact JK-l closes, and the flash SD is powered on. During SD lighting. Because the internal resistance of the circuit is much greater than the internal resistance of the SD filament, it can be equivalent to being short-circuited by SD and losing power.
However, because the capacitors cl and C2 have been charged, SD is lit for a period of time. The principle is: when BGl is on, its c pole potential is close to the power supply voltage, so that C1 is charged with positive and negative charges on the left and right, and BGl can still be positively biased and kept on. After Cl is discharged, BGl exits saturation and cuts off, and BG2 is forced to cut off. On the other hand, before the BG2 cutoff, 12V voltage is charged to C2 by BGl e-b pole, R1, R5 and BG2 c-e pole, and C2 is positive left and negative right.
C2 is discharged to the J coil through R5 and Rl, and the relay suction time is extended. C2 is discharged, J is released, SD is extinguished.
Then the next cycle begins.
The C1 on the flasher represents the maximum power output of the flash. C1 is a parameter of the flash that indicates the output capacity of the flash at full power. Different models of flash have different values for C1, usually in watt-seconds (Ws) or joules (J). The greater the C1 value, the higher the maximum output power of the flash, which can provide stronger light exposure. When using the flash, the photographer can adjust the value of C1 to control the brightness and exposure range of the flash.