In February's Discover Magazine:
1 Fade to black: On February 17, television stations will broadcast only digital signals, ending the run of the TV system used in the United States for the past 55 years.
2 The digital television signal can transmit pictures composed of up to 1,080 lines. That’s a long way from the first TV, demonstrated by John Logie Baird in 1926. It used just 30 lines to create a coarse image.
3 Baird’s television looked like a peep-show device, held together with scrap wood, darning needles, string, and sealing wax. His invention was partly mechanical, relying on a spinning metal disk with a spiral of holes to chop up images for transmission.
See 4-20.
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