Heart-shaped flowing water lamp

As shown in the schematic, the 18 LEDs are divided into 3 groups. When the power is turned on, the 3 transistors will compete to turn on, but due to differences in components, only one transistor will turn on first. Let's assume Q1 turns on first, then the group of LEDs 1 will light up. Because Q1 is on, its collector voltage drops, causing the voltage across capacitor C2 to drop to close to 0V. Since the voltage across a capacitor cannot change abruptly, the base of Q2 is also pulled to approximately 0V, and Q2 is cut off. Therefore, the group of LEDs connected to its collector is off. At this time, the high voltage of Q2 increases the collector voltage of Q3 through capacitor C3, and Q3 will also quickly turn on, lighting up the group of LEDs 3. Therefore, during this period, the collectors of Q1 and Q3 are both at a low level, and groups of LEDs 1 and 3 are lit, while group 2 is off. However, as the power supply charges C2 through resistor R2, the base voltage of Q2 gradually increases. When it exceeds 0.7V, Q2 changes from the cut-off state to the on state, the collector voltage drops, and group 2 lights up. Simultaneously, the voltage drop at the collector of Q2, through capacitor C3, also lowers the base voltage of Q3, causing Q3 to change from conducting to cutoff. Its collector voltage then rises, turning off LED3. Next, the circuit cycles through the process described above, with the 18 LEDs in the 3 groups being lit in turn, and at any given time, 12 LEDs in 2 groups being lit. These LEDs are arranged in a cross-hatched heart pattern, continuously flashing and emitting light in a dynamic display effect.