How They Work - Red Letter Game and OK Game on Bounty
Walk up to a bingo, get the OK feature lit, and you probably have to read the instruction card to find out what it does - then ask someone to explain what the instruction card meant.
When the feature re-appeared on mystic line machines, they changed the name from OK game to red letter game. It made the instruction card slightly more readable, and the explanation you got from someone who knew was a little less convoluted.
If you read the write-up on OK Games, you're probably in the same boat. You now want to ask someone what it meant. Maybe this write-up will help - but probably not.
Briefly, if you succeed in winning an ok/red letter game, the machine resets and scores/features ratchet up to certain predefined levels as indicated on an award card attached to the bottom of the playfield. The score levels and features that will enable correspond to what letter in the game name on the backglass is backlight with a red lamp. You can still play additional coins/credits after the reset sequence to further improve scores/features if you wish - once the reset sequence completes, the remaining game play is standard.
To win an ok/red letter game, you need the feature enabled and pot at least two balls in holes that meet the requirements - two numbers in the orange section on bounty, or two or three star numbers lit on a mystic line game. It's much easier to win on bounty.
Besides changing the feature name from OK to red letter, the way the circuits reset the machine and ratchet up the scores and features to the correct levels is completely different. The circuit changes actually started on Bounty, which still used the "OK game" term, and carried through all the rest of the machines that used the red letter game. One other change, though, is while the OK game machines (including Bounty) directly or indirectly tied the new game guaranteed settings to the green score level, the later games tied to the red score.
The Principle Ingredients
We will be using Bounty as the example machine, with the "O" being the lit red letter. For later games, replace "green score disc" with "red score disc" and they renamed the "ok unit" back to "red letter unit" - even though it doesn't do the same thing as it used to.
The early OK games had a red letter feature unit which was controlling the game reset sequence to set the scores to the right levels and enable the correct features. The somewhat odd thing was the red letter feature unit stepped up every time the green score unit stepped up. If the green score unit had enough available rivets/wipers, the circuits could have been implemented on it and the red letter unit wouldn't be needed. It's also possible that the original intent was to have the red letter unit step up independently of any of the scores, but they couldn't figure out a decent way to proportion it, so they just tied the step-up to the green scores and got proportioning for free.
In any case, on Bounty the green score unit itself lit the red letter in the game name and also directly drove the reset circuits in a much simpler way than the earlier OK games did. The reset process still ratcheted up the scores and enabled the features in a sequential manner, but a stepper unit was doing it rather than a series of relays. The sequence still included the following, but the order they occur can change:
- red odds step-up to correct level
- yellow odds step-up
- magic screen feature unit step up to enable screen movement
- selection feature unit step-up to enable rollovers and before/after 5th
- red or yellow supersection lights