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Day in Engineering History Archive - April 9

| 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.
Please submit significant historical events and dates for inclusion in these lists. I will be glad to include your name and birthday. Please do not submit your death date ;-)
A couple 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.

April 9

James McDonnell's Birthday - Please click here to visit RF Cafe.

1770: Thomas Seebeck, who discovered that an electric current flows between different conductive materials that are kept at different temperatures (Seebeck Effect), was born. 1864: Sebastian de Ferranti, an electrical engineer who developed the first 10 kV (4x previous) transmission system and components, was born. 1865: Robert E. Lee surrendered to Ulysses S. Grant at Appomattox Courthouse in VA. 1895: Astronomer James Keeler proved the rings of Saturn were composed of meteoric particles. 1899: James McDonnell, founder of the McDonnell Aircraft Company, was born. 1927: Bell Laboratories and the Department of Commerce held the 1st long-distance transmission of a live picture and voice (television) simultaneously. 1934: Oskar von Miller, who pioneered the electric power industry in Germany, was born. 1940: Germany invaded Denmark and Norway. 1953: Man in the Dark, the first 3D motion picture produced and released by a major company, was shown. 1959: NASA announced the selection of America's first seven astronauts: Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard and Donald Slayton. 1963: Winston Churchill becomes first honorary U.S. citizen. 1965: "TIME" magazine featured a cover with the entire "Peanuts" gang. 1967: The first Boeing 737 made its maiden flight. 2003: Newly liberated Iraqi citizens toppled a statue of Saddam Hussein in Baghdad.


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RF Cascade Workbook is a very extensive system cascaded component Excel workbook that includes the standard Gain, NF, IP2, IP3, Psat calculations, input & output VSWR, noise BW, min/max tolerance, DC power cauculations, graphing of all RF parameters, and has a graphical block diagram tool. An extensive User's Guide is also included. - Only $35.
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