1. Radio

2. *Warning* Heavy Science Content Ahead

4. Baghdad battery – 250 BCE

6. Electricity was a heavy duty toy for decades, including Ben Franklin and his kite, people rubbing cat skins on glass or amber rods, spinning sulfur balls, and sparking everything and everyone in sight Electricity was a heavy duty toy for decades, including Ben Franklin and his kite, people rubbing cat skins on glass or amber rods, spinning sulfur balls, and sparking everything and everyone in sight

7. Luigi Galvani - 1786 Believed everything contained electricity Looked for “animal magnetism” Touched different metals to frogs’ legs which twitched

8. Alessandro Volta - 1796

9. Volta took Galvani’s experiment and showed that it was the current produced by the different metals that caused the twitch Built a pile of alternating sandwiches of zinc and copper in an acid and created electicity

10. Hans Christian Oersted - 1820

11. Oersted’s experiment - 1820 In a lecture in Copenhagen he performed an experiment to demonstrate there was no connection between electricity and magnetism by showing that an electric current passing through a wire wouldn’t affect a nearby compass needle In a lecture in Copenhagen he performed an experiment to demonstrate there was no connection between electricity and magnetism by showing that an electric current passing through a wire wouldn’t affect a nearby compass needle

12. Imagine his surprise when the needle swung the moment he turned on the current Imagine his surprise when the needle swung the moment he turned on the current He demonstrated that electricity created a magnetic field He demonstrated that electricity created a magnetic field

13. William Sturgeon - 1825 Created the first electromagnet by wrapping wire around a soft iron bar and sending a current through the wire Electricity can create magnetism

14. Michael Faraday - 1826 Reversed Sturgeon’s experiment Showed that magnetism could create an electric current

15. Samuel F. B. Morse - 1838

17. Used a an on-off switch – the telegraph key – to turn an electric current on and off, sending pulses of current through a wire to an electromagnet that would click in time to the pulses

19. Johannes Mueller - 1840

20. Examined physical sensations Examined physical sensations Can you feel colors Can you feel colors Can you hear shapes Can you hear shapes Can you smell sounds Can you smell sounds Discovered that each sense detects different things Discovered that each sense detects different things We think this is obvious, but no one had proven it before. Remember “common sense”? We think this is obvious, but no one had proven it before. Remember “common sense”?

21. Herman Hemholtz - 1857

22. Meuller’s pupil Meuller’s pupil Investigated hearing Investigated hearing Noticed sound produced vibrations Noticed sound produced vibrations

24. Did the vibrations operate at different frequencies? Did the vibrations operate at different frequencies? They did They did Thus, sound traveled at different frequencies Thus, sound traveled at different frequencies Used an electromagnet to attract the arms of a tuning fork, causing it to vibrate and produce sound Used an electromagnet to attract the arms of a tuning fork, causing it to vibrate and produce sound

25. Leon Scott de Martinville - phonautograph - 1857 Attached a bristle to a membrane at the end of a cone, set the bristle to touch a piece of smoked glass Spoke into the cone membrane vibrated to the sound and the bristle etched a wavy line onto the smoked glass

27. The Telephone - 1876 Scott’s membrane, Faraday’s electromagnet, Oersted’s and Sturgeon’s electromagnet, Morse’s wire and electrical current, Hemholtz’s vibration, Scott’s membrane Scott’s membrane, Faraday’s electromagnet, Oersted’s and Sturgeon’s electromagnet, Morse’s wire and electrical current, Hemholtz’s vibration, Scott’s membrane

28. Bell and Gray

29. Samuel Morse

30. Heinrich Hertz - 1886

31. Hemholtz’s pupil Hemholtz’s pupil Investigated whether electricity traveled in frequencies the way sound did Investigated whether electricity traveled in frequencies the way sound did

32. Spark gap generator

33. Hertz’ spark gap experiment

34. Demonstrated that electricity traveled through air at specific frequencies, just like it did through wires

35. Guglielmo Marconi - 1894

36. Marconi radio

37. Morse key

38. Marconi and his radio

39. Nikola Tesla

40. Tesla coil - 1891 Developed the first amplifier coil, the Tesla coil Developed the first amplifier coil, the Tesla coil Raised the voltage of an electrical current high enough to allow the air to conduct the current Raised the voltage of an electrical current high enough to allow the air to conduct the current Key to wireless transmission of radio waves Key to wireless transmission of radio waves

41. Reginald Fessenden

42. Felt that the variation in electrical amplitude created by a voice, just like on a telephone, could be carried by electrical wave of a radio signal Felt that the variation in electrical amplitude created by a voice, just like on a telephone, could be carried by electrical wave of a radio signal Did the first voice broadcast in 1900 Did the first voice broadcast in 1900 Short range Short range Poor quality Poor quality Needed far more power Needed far more power

43. Ernst Alexanderson

44. Developed the Alexanderson Alternator, a machine capable of generating the power, up to 100,000 hertz, that Fessenden needed to piggyback voice onto radio waves Developed the Alexanderson Alternator, a machine capable of generating the power, up to 100,000 hertz, that Fessenden needed to piggyback voice onto radio waves In Dec. 1906, Fessenden did the first good voice and music broadcast, going hundreds of miles In Dec. 1906, Fessenden did the first good voice and music broadcast, going hundreds of miles Poetry and a Bible reading Poetry and a Bible reading A woman singing opera A woman singing opera A violin playing a Christmas carol A violin playing a Christmas carol

45. Lee de Forest

47. The audion tube is actually a Fleming valve (British term for tube) invented in England The audion tube is actually a Fleming valve (British term for tube) invented in England de Forest simply added the bent wire de Forest simply added the bent wire

48. De Forest’s audion tube - 1904

49. Audion tube amplified the radio signal the way the Alexanderson generator increased the electrical power Audion tube amplified the radio signal the way the Alexanderson generator increased the electrical power de Forest didn’t know how the audion worked de Forest didn’t know how the audion worked Another man did Another man did

50. Edwin Howard Armstrong

51. Investigated the audion tube, figured out how it worked, and improved it Investigated the audion tube, figured out how it worked, and improved it Developed “regeneration” Developed “regeneration” The signal was fed back into the tube over and over again, up to 20,000 times a second The signal was fed back into the tube over and over again, up to 20,000 times a second Vastly increased the power of the tube to output the signal – it was an amplifier Vastly increased the power of the tube to output the signal – it was an amplifier Raise the level enough and the tube becomes a transmitter Raise the level enough and the tube becomes a transmitter Armstrong invented the ability to broadcast sound Armstrong invented the ability to broadcast sound

52. It combined high frequency waves with low frequency waves, then fed them back into the system to amplify the signal and increase its sensitivity It combined high frequency waves with low frequency waves, then fed them back into the system to amplify the signal and increase its sensitivity Resulted in the creation of the home, and the portable, radio Resulted in the creation of the home, and the portable, radio

53. Armstrong’s superheterodyne Armstrong’s next invention was the superheterodyne Armstrong’s next invention was the superheterodyne

54. Crystal Radio

55. David Sarnoff

56. Enamored of radio Enamored of radio Saw the possibilities Saw the possibilities

57. Prior to radio, communication was point to point It was one voice reaching one person at a time Books Letters Telegrams Movies could reach tens or hundreds at a time, but it required affirmative action on the part of the audience

58. Sarnoff wrote the “Radio Music Box Memo” that outlined the commercial possibilities of radio Sarnoff wrote the “Radio Music Box Memo” that outlined the commercial possibilities of radio

59. RCA (Radio Corporation of America) After World War I After World War I Four companies merged their patents to create RCA Four companies merged their patents to create RCA American Marconi American Marconi General Electric General Electric American Telephone & Telegraph American Telephone & Telegraph Westinghouse Westinghouse Sarnoff named as commercial manager Sarnoff named as commercial manager

60. Used Armstrong’s inventions, building superheterodyne radios to build RCA, the Radio Corporation of America, into one of the biggest companies in the world Used Armstrong’s inventions, building superheterodyne radios to build RCA, the Radio Corporation of America, into one of the biggest companies in the world

61. Radio stations soon opened all over the U.S. Including KWSC (now KWSU) in 1922, one of the first radio stations in the country

62. Examples of programming Operas Operas Concerts Concerts Sports Sports News News Dramas Dramas Comedies Comedies Variety shows Variety shows Soap operas Soap operas Pretty much everything we get on TV today

63. Fibber McGee and Molly

64. Burns and Allen

65. Fred Allen

66. Abbott and Costello

67. Orson Welles - 1938

68. Sound Recording

69. We need to backtrack a bit to understand sound recording

70. Leon Scott de Martinville - phonautograph - 1857 Attached a bristle to a membrane at the end of a cone, set the bristle to touch a piece of smoked glass Attached a bristle to a membrane at the end of a cone, set the bristle to touch a piece of smoked glass Spoke into the cone Spoke into the cone membrane vibrated to the sound and the bristle etched a wavy line onto the smoked glass membrane vibrated to the sound and the bristle etched a wavy line onto the smoked glass

71. Spring of 2009 scientists were able to get sound from one of de Martinville’s paper phonautographs – a woman singing for 10 seconds

72. Thomas Edison

75. Tinfoil phonograph – 1877

77. Close-up on bumps

78. Chichester Bell / Charles Tainter

79. Bell and Tainter’s phonograph – 1885

80. Close-up

81. Emile Berliner

82. Berliner Gramophone – 1887

83. Eldridge Johnson / Gramophone

84. “Little Nipper”

85. Mechanical recording session

86. Electrical Recording

87. Valdemar Poulsen

88. Telegraphone – 1897

89. Close up of telegraphone

90. Telegraphone – 1915

91. Fritz Pfleumer

92. Magnetic tape

94. BASF/AEG Magnetophone – 1935

95. Carbon granule mic

96. Condenser Microphone

97. Ribbon mike

98. Electrical recording session

99. Radio was mostly entertainment Constantly needed new material New forms of music became popular Blues Jazz Country

100. Bessie Smith

101. Fiddlin’ John Carson 1923 “little Old Log Cabin in the Lane” became first country hit

103. For 20 years the country was bound together by a common source of information and social norms – the radio

104. Roy Brown

105. Todd Storz

106. Alan Freed

109. Back to tape

111. Reel to reel tape recorder – 1948

112. Cassette tape – 1963

113. Norelco CarryCorder – 1965

114. Sony Walkman – 1979

115. Digital Revolution

116. Close up of record grooves

118. CD pits

120. Radio and Journalism

121. Hindenburg disaster - 1937

122. Edward R. Murrow

123. The Advent of Television

124. It was assumed that radio would be dead It was assumed that radio would be dead Audiences would watch TV instead of listening to the radio Audiences would watch TV instead of listening to the radio TV took over so many of the radio programs TV took over so many of the radio programs Soap operas Soap operas Dramas Dramas Sitcoms Sitcoms Sports Sports news news

125. Radio had a great advantage over TV – Portability

126. Take it anywhere

127. Even in the car

128. New kinds of programming Music Music Top 40 Top 40 Country Country Rock Rock Easy listening Easy listening Golden oldies Golden oldies Talk shows Talk shows

129. Howard Stern

130. On the Right Rush Limbaugh Michael Savage Glenn Beck

131. On the Left Ed Schultz Stephanie Miller