On Hein Veldhuis’s website (link) you can see a photo and read about the Turbo 16K prototype which was shown at the Nuremburg Toy Fair in February 1985. At the time it was assumed that this was a final product but as you will see the Turbo 16K changed quite dramatically between February and the end of 1985 when it was released. These rapid changes of product were typical of the chess computer market of the mid-1980s.

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