The Used Letter Board is one of the set pieces on Wheel of Fortune.
History[]
Since the beginning, Wheel of Fortune has used an off-screen device to keep track of which letters have been called, as well as contestants' scores. Equivalents are present in the Video games, as the viewing audiences of the show itself can't see it.
During the Shopper's Bazaar pilot, a row at the bottom of the puzzle board indicated letters which were called but not in the puzzle.
It is not known if the two Edd Byrnes pilots had any sort of off-screen indicator. The first known reference to the Used Letter Board is January 18, 1978, when Susan Stafford pointed to it after a repeated letter had been called.
Originally, the Used Letter Board used cards with all 26 letters of the alphabet, which were flipped over as one was called. It also featured a chalkboard on which stagehands kept track of each contestant's score. Because of this, Speed-Up rounds often had faint tapping and scratching sounds in the background.
By 1988, the Used Letter Board was changed to a whiteboard. It is believed this was the case until 1997 when the electronic puzzle board debuted, at which point the board was changed to a monitor. Said monitor shows the 21 consonants first, then the five vowels underneath in a different color, and the category. A second monitor also displays each contestant's score, as well as a countdown timer (five seconds for main-game rounds, ten seconds for the Bonus Round). It also indicates the Prize Puzzle, and the Jackpot total when that was in use.
Despite its importance to the show, the Used Letter Board has very rarely been seen on-camera. It was first shown on-camera on December 4, 2000 during the post-game chat where Pat and Vanna demonstrated how it works. Perhaps the most notable instance is March 19, 2014, when contestant Emil solved the bonus puzzle NEW BABY BUGGY with only the N and E revealed, and explained that he used the board to help him figure out the answer.