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MECA Electronics Attenuators

Day in Engineering History Archive - July 31

July 31

Samuel Hopkins Awarded 1st U.S. Patent - Please click here to visit RF Cafe.1790: The first U.S. patent was issued to Samuel Hopkins for his process for making potash and pearl ashes. 1792: The foundation stone of the U.S. Mint in Philadelphia was laid. 1918: Francis Stanley (not his twin brother Freelan), famous for their Stanley Steamer automobile, died. 1923: Stephanie Kwolek, inventor of Kevlar, was born. 1937: Charles Hires of root beer fame died. 1965: The last cigarette commercial appeared on British television. 1964: Space probe Ranger 7 transmitted the first close-up images of the moon's surface ever taken by a U.S. spacecraft. 1969: A Moscow police chief reported that thousands of Moscow telephone booths had been made inoperable by thieves who had stolen phone parts in order to convert their acoustic guitars to electric. 1971: Astronauts rode in a vehicle on the moon for the first time in a lunar rover vehicle (LRV). 1998: IBM's Russian subsidiary agreed to pay $8.5 million in fines for selling powerful computers ultimately destined for a Russian nuclear weapons laboratory. 2003: Felix Baumgartner was the first to cross the English Channel by unpowered flight when he jumped from 30,000-ft and glided 22 miles wearing a birdman suit.

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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.

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RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

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