Day in Engineering History Archive - January 7

January 7

Marconi Established 1st Distress Signal - RF CafeDay in Engineering History January 7 Archive - RF Cafe1610: Galileo Galilei sighted four of Jupiter's moons (Io, Europa, Ganymede, and Callisto). 1785: Jean Blanchard and John Jeffries made first air crossing of the English Channel from England to France in a hot-air balloon (first international flight). 1904: Marconi established "CQD" (-·-· --·- -··, CQ=be quite and listen, D=distress) as the first international radio distress signal, but two years later, "SOS" (··· --- ···, Save Our Souls) became the radio distress signal because it was faster to send by wireless radio. 1927: Commercial transatlantic telephone service was inaugurated between New York and London. 1935: Sir Alfred Ewing, the physicist who discovered and named hysteresis, died. 1943: Serbian-American high voltage experimenter Nikola Tesla died. 1980: The first solar-cell power plant  was dedicated at Natural Bridges National Monument, UT (266,029 solar cells in 12 producing 100 kW). 1998: Richard Hamming, of error correction code fame, died. 2004: American electrical engineer Oswald "Mike" Villard Jr., who developed over-the-horizon radar, died.

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Note: These historical tidbits have been collected from various sources, mostly on the Internet. As detailed in this article, there is a lot of wrong information that is repeated hundreds of times because most websites do not validate with authoritative sources. On RF Cafe, events with hyperlinks have been verified. Many years ago, I began commemorating the birthdays of notable people and events with special RF Cafe logos. Where available, I like to use images from postage stamps from the country where the person or event occurred. Images used in the logos are often from open source websites like Wikipedia, and are specifically credited with a hyperlink back to the source where possible. Fair Use laws permit small samples of copyrighted content.