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Day in Engineering History Archive - April 23

Day in Engineering History April 23 Archive - RF CafeHappy Birthday Max Planck! - Please click here to visit RF Cafe.April 23

1858: Max Planck, who introduced quantum theory to the world, was born. 1896: The Vitascope system for projecting movies onto a screen, invented by Francis Jenkins and Thomas Armat, was demonstrated in New York City. 1915: The A.C.A. became the National Advisory Council on Aeronautics (NACA), which later became NASA. 1940: The Ray-o-Vac leak-proof flashlight battery was patented by Herman Anthony. 1955: Congress ordered all U.S. coins to bear motto "In God We Trust." 1968: The first decimal coins were distributed in Britain in preparation for replacing the current system of pounds, shillings and pence. 1985: Coca-Cola Co. announced it was changing the secret formula for Coke. 1994: The subatomic particle called the top quark was discovered at the DoE's Energy's Fermi National Accelerator Lab.

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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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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

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 World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

Copyright  1996 - 2026

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

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