Shutter Panel (bingo)
A thin wooden board mounted to the bottom of the playfield.
When slid away from the player, holes in the board would allow
the balls to drop beneath the playfield onto another sloping
board, which would direct the balls into the ball trough. The
shutter panel normally closes when the first ball lifts the
ball gate on a completely reset machine. Complete reset of the
machine requires all balls to be in the ball trough, so if you
power off a game with a ball in the ball runway, then power
on and start a game, shooting the first ball will not close
the shutter. Once all the balls are beneath the playfield, reset
is complete and shooting the next ball will close the shutter.
