Tank Kee Games, August 1974 I believe these two boards are tightly back-to-back, and the edge connector on each forms a single, double-sided edge connector. The manual warns that the two boards should not be pried apart. Board I (J-3) | Board II (J-6) ------------------------------------|-------------------------------------- (From Transformer?) Gnd | 1 | 1 | Gnd (Left Joysticks Common) LO - AC | 2 | 2 | Analog Gnd (to J-3, pin 7) LO - AC | 3 | 3 | HI - AC | 4 | 4 | HI - AC | 5 | 5 | (Speaker 1 & 2 Common) Gnd | 6 | 6 | (from J-6, pin 2) Gnd | 7 | 7 | | 8 | 8 | Ant | 9 | 9 | +5V |10 | 10| P2 Left Joystick, Down Coin 2 - NC |11 | 11| P2 Right Joystick, Down Coin 2 - NO |12 | 12| P2 Left Joystick, Up Coin 1 - NC |13 | 13| P2 Right Joystick, Up Coin 1 - NO |14 | 14| -12V |15 | 15| P1 Left Joystick, Down Speaker 2+ |16 | 16| P1 Right Joystick, Down Speaker 1+ |17 | 17| P1 Left Joystick, Up |18 | 18| P1 Right Joystick, Up |19 | 19| P2 Button Coin Counter |20 | 20| P1 Button (Speaker 1 & 2 Common) Gnd |21 | 21| Video (Coin 1 & 2 Common) Gnd |22 | 22| Gnd (from Video) --------------------------------------------------------------------------- AC Power @ 110V/60Hz, stepped down to 6.3V Is the AC Power only used for powering the B/W television? I have no idea what "Ant" is. The schematic doesn't show it going to anything.