Techno Stuff
How They Work - Timer Unit

Almost every game has one of these, and it's function can be a little confusing, so let's take a look at what it does.

  • allows the ball lifter motor to power to raise balls 2-5. and closes the shutter panel on the playfield to keep balls from dropping through.
  • trips the before 4th trip relay, which generally enables payout on most games.
  • controls things that happen when a certain number of balls are shot : "do something now" flashing lights, enable extra ball play, etc.
  • on early games, will tilt the game after it steps up to it's maximum (39 steps on surf club). on later games, it shuts off the motors after stepping up to top (usually only 10 steps or so).

As usual, we will start with the diagram in the manual and look at the circuits on the schematic.

timer disc
surf club
timer disc diagram - click for big version


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