Pulse generator LM324
This is an LED flasher that makes an LED flash on and off rapidly. Using this flasher, you make the LED flash for a moment and go out, flash again and go out, and repeat this cycle over and over. This is a pulse generator which works in the following way.
When you switch power ON, an output voltage is produced and C1 is charged through R1, and LED 1 stays on while C1 is charged. As the charging of C1 goes on, the output voltage goes down to 0. Then the current stops flowing to C1 and LED 1 goes out.
Then, the charge stored in C1 is discharged through R2. When C1 is discharged to a certain extent, the circuit restores the original power-ON state. This cycle repeats itself continuously. Do you get LED 1 winking all right?
Then, see how its flickering changes when you use different values for R1 and R2. You'll notice that it goes on and off slowly when R2 is increased, and fast when R2 is decreased.