Basic Slot Machine
Basic System Diagram

INPUT Coin and Push Button create the two inputs.  Each Event is used to trigger a Digital Gate.  Both Events have to happen close together.

PROCESSOR 1 RC1 Controls the Timing of the Roll-Down PROCESSOR 2 There Must Be 2 Seperate 4046-VCOs Otherwise the LEDs match all the time.   PROCESSOR 3 Two Seperate 4017  Walking Ring Decade Counter to control LEDs   OUTPUT 1 LEDs   PROCESSOR 4 Do The Two Rows of LEDs Match? OUTPUT 2 Jack Pot Pay a Quarter

 

Play pennies.  Pay Quarters.  If the odds to win here are 1 in 100, the owner of the machine is the real winner.

Used "Change Dispensers" can be purchased for $25 on the internet.