When the Ball Count unit is reset, it's in a position that the schematic calls position 0. In positions 0,2,4,6 & 8, the 1st Player Scoring Control (AA) relay should be energized. In positions 1,3,5,7 & 9, the 2nd Player Scoring Control (BX) relay should be energized. Also, in later positions as shown on the schematic, the Last Ball (XB) relay should energize.
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