Timer 555
Pile ou Face / Heads or Tails

Electronic 'Heads-or-tails' coin toss circuit. Basically a Yes or No decision maker when you can't make up your mind yourself.

The 555 is wired as a Astable Oscillator, driving in turn, via pin 3, the 7476 flip-flop. When you press S1 it randomly selects the 'Heads' or 'Tails' led.

The leds flashrate is about 2Khz (kilo-Hertz), which is much faster than your eyes can follow, so initially it appears that both leds are 'ON'. As soon as the switch is released only one led will be lit.