How X-units work

[OldReno]

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

[OldReno]

More on x units
When a pay hits, the hopper starts running. The idea is to turn off the hopper so it doesnt dump out all the coins. So we must move the wiper fingers on the payboard so that they step off of the hot pay segment that keeps the hopper going. When they step off hopper stops, even tho' that pay segment is still hot, it's no longer making contact. You can verify this by pushing back the timing bar above the reel mech clock & resetting hopper. You can keep doing it over and over until you start a new game.
On a 1 coin played pay, the signal originates from the hopper coin out roller and switch. It then goes up to odds disc to see which xunit is selected (none if 1 coin played) and then pulses that xunit coil one time for each coin out. When it pulses AND the signal gets accross that xunit's hot segment (see last post) then the pulse goes back down to hopper and allows payboard step up coil to step once. When this happens correctly enough times the payfingers eventually step off hot pay segment and pay is over.
Machines with xunits have a thing called delay relay which will work to shut down pay quickly if there is a runaway. Part of that circuitry is the tiny microswitch which rides on the outer ring of your 100 tooth payboard gear.
Now, if the odds disc finger to select xunits is lifted & makes no contact, the signal cannot get back to hopper to stop it & you have runaway on ANY odds played. If x2 wiper board is bad it runs away only on 2 coins played. Same with 3 or 4 or 5 coins played. Hope i havent confused you.