SPACE INVADERS 18 PIN CONN 16 PIN CONN 13 PIN CONN 1 +5V 1 1 GND 2 +5V 2 COIN SW 2 1 RIGHT 3 +12V 3 COIN SW 3 1 LEFT 4 +12V 4 GND 4 5 -5V 5 CTR 5 KEY 6 6 RESET 6 1 FIRE 7 7 7 1 START 8 8 SP 8 2 START 9 9 SP 9 10 10 AUDIO VOLTAGE RETURN 10 2 FIRE 11 11 AUDIO VOLTAGE 11 2 LEFT 12 12 O-B TO MONITOR 12 2 RIGHT 13 13 GND 13 14 GND (- SENSE) 14 15 GND 15 16 16 17 MONITOR 18 MONITOR