1. ECE 1304 Introduction to Electrical and Computer Engineering What is Electrical Engineering? Part 3 (1920 to 1950)

2. What is Electricity? Electromagnetism is a property of the universe that may be used to … –Transmit and convert energy. –Transmit and manipulate information. Electrical Engineers use these properties to make useful things.

3. 1920 – 1930 1920’s – Safety standards introduced for electric outlets. 1920 – First commercial radio station, KDKA in Pittsburgh, begins broadcasting. 1925 – John Baird transmits the first recognizable image. 1926 – General Electric introduces refrigerator with hermetically sealed compressor. 1927 – transmits first television image.

5. Herbert Hoover Jr, 1923

6. Philo T. Farnsworth (1906-1971) 1927 Invented the image dissector camera tube. This was the first all electronic image scanning device.

9. 1930 – 1935 1930 – Vladimir Zworykin improves the television camera. 1932 – Construction begins on Hoover Dam. 1932 – Electric dishwasher introduced. 1933 – Tennessee Valley Authority is established. 1933 – Edwin Howard Armstrong invents frequency modulation (FM). 1934 – First coiled filament electric lamp introduced.

10. Valdimir K. Zworykin (1888-1982) 1931 Developed the Iconoscope (an improved TV camera).

12. 1932

14. 1935 – 1940 1935 – Rural Electrification Administration established. 1936 – NBC makes the first regular telecasts. TV broadcasting is suspended during World War II and resumes in 1946. 1939 – John Atanasoff and Clifford Berry invent the first electronic computer at Iowa State University. 1939 – Henry Boot and John Randall develop resonant- cavity magnetron (microwave source for RADAR).

15. Rural Electrification

18. Cutaway of a Resonant Cavity Magnetron

25. 1940 – 1945 1940 – Radar development begins (to win WWII). 1942 – 800 rural electric cooperatives with 350,000 miles of lines. 1942 – Enrico Fermi achieves first controlled nuclear reaction at the University of Chicago. 1945 – Alan Turing publishes his paper on the Universal Machine, laying out the principles of the modern computer. 1945 – John Von Neumann describes the stored-program computer. 1945 – Atomic bombs dropped on Hiroshima and Nagasaki, Japan, ending World War II.

26. Enrico Fermi (1901-1954) 1942 Built the Chicago Pile-1 in a squash court under the bleachers at Stagg Field at the University of Chicago. Achieved a controlled nuclear reaction.

27. Chicago Pile-1

28. Alan Turing (1912-1954) 1938 Worked for the Government Code and Cypher School at Bletchley Park breaking German codes. 1946 Delivered a paper describing a stored-program computer commonly known as a Turning Machine. 1948 Defined a standard for artificial intelligence know as the Turing Test.

29. John von Neumann (1903-1957) Played a part in the Manhattan Project that resulted in the atomic bomb developed at Los Alamos New Mexico. July 16, 1945 Eye witness to the first detonation of a nuclear weapon near Socorro New Mexico. 1945 Described the design of a stored- program computer that came to be known as the von Neumann architecture.

31. You are here. Trinity Bomb Site About 270 miles

32. 1945 – 1950 1946 – ENIAC, the first electronic digital computer put into operation at the University of Pennsylvania. 1946 – Microwave oven introduced by Percy Spencer. 1947 – John Bardeen, Walter Brattain and William Shockley of Bell Telephone Laboratories invent the transistor.

33. ENIAC - 1946

34. Percy Spencer (1894-1970) Raytheon Engineer, while working with microwave radar equipment accidently melted a candy bar in his pocket, the rest is history.

36. John Bardeen Walter Brattain William Shockley

37. John Bardeen (1908-1991) designed the experimental devices. Walter Brattain (1902-1987) described the mathematical description. William Shockley (1910-1989) manager of the research group.

38. 1 st Transistor – 1947