R-Button (bingo)
A button on the foot rail with a single letter R on it. In
order to score your wins, you need to push the R-button. On
games where you could rearrange winning combinations via things
like the magic screen, you need to push the R-button for every
winning combination you set. The main reason for the R-button
was to have more control over when scoring happened, and it
had the nice side effect of reducing wear in the game, as the
search disc was held stationary until the R-button was pushed.
On earlier games where the search disc was rotating constantly,
the contacts on the search disc and the search relays would
wear away.
