Mechanical television

Television that relies on a scanning device to display images

Mechanical television or mechanical scan television is an obsolete television system that relies on a mechanical scanning device, such as a rotating disk with holes in it or a rotating mirror drum, to scan the scene and generate the video signal, and a similar mechanical device at the receiver to display the picture. A mechanical television receiver was also called a televisor. This contrasts with vacuum tube electronic television technology, using electron beam scanning methods, for example, in cathode-ray tube (CRT) televisions.

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