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Day in Engineering History Archive - April 21

April 21

Happy Birthday to Jean-Baptiste Biot (Biot-Savart Law)!  Please click here to visit RF Cafe.Day in Engineering History April 21 Archive - RF Cafe1774: Jean-Baptiste Biot, co-developer of the Biot-Savart law of electromagnetic induction, was born. 1836: General Sam Houston defeated Santa Anna at the Battle of San Jacinto, which decided the independence of Texas. 1910: Samuel Clemens (aka Mark Twain) died, the same year as an appearance of Halley's Comet and, amazingly, the comet's previous appearance came during November 1835, the year of Clemens' birth (throughout his life, Clemens said that he would "go out with the comet"). 1918: German fighter ace Manfred von Richtofen, "The Red Baron," was shot down and killed during World War I. 1948: The first Polaroid camera was sold. 1972: Apollo 16 astronauts John Young and Charles Duke explored the surface of the moon in their LEM.

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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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Copyright: 1996 - 2018
Webmaster:
    Kirt Blattenberger,
    BSEE - KB3UON

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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