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Day in Engineering History Archive - December 21

Day in Engineering History December 21 Archive - RF CafeDecember 21

Winter Solstice.  Please click here to visit RF Cafe1807: Joseph Fourier's memoir "On the Propagation of Heat in Solid Bodies," was read to the Paris Institute, and contained what we now call Fourier series, which he had worked upon since around 1804. 1878: Jan Łukasiewicz, who invented Reverse Polish Notation (RPN), was born. 1898: Scientists Pierre and Marie Happy Hanukkah!  Please click here to visit RF Cafe.Curie discovered the radioactive element radium. 1929: My father, "Arthur Blattenberger, was born. 1968: Apollo 8, the first manned voyage to the moon, was launched. 1988: A Libyan terrorist's bomb exploded aboard Pan Am Flight 103, a Boeing 747, over Lockerbie, Scotland, killing 270 people. 1990: American aeronautical engineer Kelly Johnson, who founded the Lockheed Skunk Works, died. 2012: The Long Count of the Mayan calendar will cycle.

| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |

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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Kirt Blattenberger - RF Cafe Webmaster
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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