Time is the coin of your life. It is the only coin you have, and only you can determine how it will be spent. Be careful lest you let other people spend it for you. ~ Carl Sandburg
1866 – Anne Sullivan, American educator is born.
Johanna “Anne” Mansfield Sullivan Macy, better known as Anne Sullivan, was an American teacher, best known for being the instructor and lifelong companion of Helen Keller. She contracted trachoma, a highly infectious eye infection, when she was eight years old which left her blind and without reading or writing skills. She received her education as a student of the Perkins School for the Blind where upon graduation she became a teacher to Helen.
1898 – Harold Stephen Black, inventor of the negative feedback amplifier, is born.
Harold Stephen Black was an American electrical engineer, who revolutionized the field of applied electronics by inventing the negative feedback amplifier in 1927. To some, his invention is considered the most important breakthrough of the twentieth century in the field of electronics, since it has a wide area of application. This is because all electronic devices (vacuum tubes, bipolar transistors and MOS transistors) are inherently nonlinear, but they can be made substantially linear with the application of negative feedback. Negative feedback works by sacrificing gain for higher linearity (or in other words, smaller distortion or smaller intermodulation). By sacrificing gain, it also has an additional effect of increasing the bandwidth of the amplifier. However, a negative feedback amplifier can be unstable such that it may oscillate. Once the stability problem is solved, the negative feedback amplifier is extremely useful in the field of electronics. Black published a famous paper, Stabilized feedback amplifiers, in 1934.
1956 – In Chicago, videotape is first demonstrated.
The Mark IV was the machine first publicly demonstrated at the National Association of Radio and Television Broadcasters (now the NAB) convention (the NAB Show) in Chicago on April 14, 1956. After William Lodge of CBS finished his speech, the Mark IV replayed his image and words almost immediately, causing “pandemonium” among the astonished attendees. The earlier Mark III was given some cosmetic improvements, and was also demonstrated at Ampex headquarters in Redwood City the same day. Both demonstrations were a success, and Ampex took $2 million in orders for the machine in four days.
2003 – The Human Genome Project is completed with 99% of the human genome sequenced to an accuracy of 99.99%.
The Human Genome Project was declared complete in April 2003. An initial rough draft of the human genome was available in June 2000 and by February 2001 a working draft had been completed and published followed by the final sequencing mapping of the human genome on April 14, 2003. Although this was reported to be 99% of the human genome with 99.99% accuracy a major quality assessment of the human genome sequence was published on May 27, 2004 indicating over 92% of sampling exceeded 99.99% accuracy which is within the intended goal. Further analyses and papers on the HGP continue to occur.
2009 – Songs for making things…
Check out this fun vintage Adafruit post featuring a video of Phil shipping to Morrisey!
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