Flip-disc display

Flip-disc display elements (close up). The disc rotates on the shaft that is carried in the two triangular posts. The magnet that powers the rotation can be seen embedded in the disc. Under the disc is the driving solenoid; when powered, a field is induced into the two posts, flipping the discs. Rotation stops when the disc hits the post.
DOT-LED display of a bus Irisbus Citybus 18M (made 2004), photographed while a change is scrolling across the board
Faulty dots are a typical malfunction of flip-disc displays.

The flip-disc display (or flip-dot display) is an electromechanical dot matrix display technology used for large outdoor signs, normally those that will be exposed to direct sunlight. Flip-disc technology has been used for external destination signs on buses and trains across North America, Europe and Australia, as well as for variable-message signs on highways. It has also been used extensively on public information displays.[1] A few game shows have also used flip-disc displays, including Canadian shows like Just Like Mom, The Joke's on Us and Uh Oh!, but most notably the American game show Family Feud from 1976 to 1995, and its British version Family Fortunes from 1980 to 2002. The Polish version of Family Feud, Familiada, still uses this board, which was bought from the Swedish version of the show.[2]

  1. ^ Norman Ball, John Vardalas, "Ferranti-Packard", McGill Queen's Press, 1994, ISBN 0-7735-0983-6
  2. ^ "Familiada", Wikipedia, wolna encyklopedia (in Polish), 2020-07-26, retrieved 2020-07-27