6 August 20

On this date in 1935, William Coolidge received a patent for the cathode ray tube, the major display element for televisions, oscilloscopes and many other electronic devices. My tie features personal computers of the "IBM AT" era, in the 1980s-early 1990s, when the hefty monitors were based on cathode ray tubes. In our house, we have one TV left that uses a CRT. It's completely offline because it can't handle digital signals, but it could be hooked up to a DVD player through those old RCA plugs.