How X-units work
X-units are selected by a wiper finger on the odds disc. 1 coin played is called zero odds, so no Xs are chosen. 2 coins played is first odds, so when the odds assy steps once, the finger choses the x2 unit for payouts, bypassing the circuit to the hopper payout step up solenoid, and instead for every coin paid out the x2 solenoid steps one time. The wire to the x2 coil ALSO is connected to the x2 board. The board has 10 tabs on it, with a wiper assy, and notice that every other tab is wired. (X3 unit has every 3rd tab wired, x4 every 4th tab and etc)
So when the xcoil gets a pulse, IF AND ONLY IF the xboard wiper is contacting a hot tab, then that tab sends voltage to hopper to step payboard one step. Also when xunit coil fires, it moves the xwiper to the next spot on the board which is not wired. Hence, no hopper step on next coin out. Rinse & repeat until payout is complete.
I hope this makes sense (cents-bad pun), and i will try to answer any questions.
Note that the x2 & X5 boards have 10 tabs, and the x3 and x4 have 12 tabs. This is because 3 and 4 do not divide evenly into 10, but they do into 12. However you can use a 12 tab board on x2, and a 10 tab board on x4 if thats all you have. But you cannot use 10 tab on x3 or 12 tab on x5, you will get short paid all the time.
Hope this helps
Thx
Craig