A new 24 second countdown timer from Milardo. The circuits uses fast 74LS schottky IC’s.
Here is how the circuit works:
A 24 second countdown starts when S3 is off and S2 is pressed.
Switch S3 is used to start/pause the countdown.
S2 resets the countdown (99 to 00) when the countdown reach 00.
To restart the countdown to 24 Seconds S1 is pressed.