Secret Diagram

Here is the circuit diagram of a seven segment counter based on the counter IC CD 4033.This circuit can be used in conjunction with various circuits where a counter to display the progress  adds some more attraction.

IC NE 555 is wired as an astable multivibrator for triggering the CD 4033.For each pulse the out put of CD 4033 advances by one count.The output of CD 4033 is displayed by the seven segment LED display LT543.Switch S1 is used to initiate the counting.Diode D1 prevents the risk of accidental polarity reversal.