Use CD4011 to make light-controlled flashing warning lights

VDI, VD2, CI and C2 form a simple capacitor step-down half-wave rectification circuit, which outputs about 9V DC voltage for
digital integrated circuits. NAND gates I and II form a light-controlled detection circuit, and NAND gates III and IV form an ultra-low-frequency oscillator.
During the day, the photoresistor RG has a low resistance when exposed to light, and the input terminal of the NAND gate I is at a low level. After being inverted by
the two stages of One input terminal is a logic level "0", the ultra-low frequency oscillator composed of NAND gates m and IV
stops vibrating, and the output level is "0", the transistor VT is cut off, and the thyristor VS has no trigger current and
is turned off. status, the light H does not light up. At night, the photoresistor RG has a high resistance when exposed to no light, causing the input terminal of the NAND gate I
to be a high level "1". After two stages of inversion, the output is still a high level "l", thereby releasing the NAND gate. When the ultra-low frequency oscillator composed of II[ and IV
is blocked, the oscillator starts to vibrate immediately, and the NAND gate IV outputs high level and low level at intervals. When the output is high level,
vs obtains the trigger current through R3 and is turned on, and the lamp H is lit and glows: when the output is low level, vs loses the trigger
current , and turns off when the alternating current crosses zero, and the lamp H goes out. So the warning light H flashes.
    Adjusting the potentiometer RP1 can adjust the light control sensitivity of the circuit so that the circuit starts working under appropriate illumination. RP2
is used to adjust the flashing frequency of warning light H.