Juan Monroy — Media Technologies: Television

Television is Old
- Edison’s Telephonoscope
Mechanical Television
- mechanical scanning
- spinning disks
  - Nipkow Disk
  - Baird Television
Nipkow Disk
- Paul Gottlieb Nipkow, 1885
  - spinning disk
  - selenium cell
  - light projects image
- low-resolution
  - 30–100 holes
  - 10–18–inch image
Bard Transmitter
- John Logie Baird, 1926
- live moving images, 1926
  - 12.5 pictures per second
  - 30-lines of resolution
- Baird is considered one of the inventors of electronic television
Electronic Television
- image on an electron plate (11,22)
- electronic scanning (19)
- line-by-line (16)
- signal carried over wire (23)
- projected on a remote screen (30) over wire or radio.
Image Dissector
- electronic video camera tube
  - replaced disks with cesium
- Philo T. Farnsworth, 1921
  - Idaho amateur inventor
  - won a patent suit vs. RCA, 1935
- basis for all TV tubes until late 20th century
Vladimir Zworkin
- electronic television at Westinghouse, beginning 1923
- recruited by RCA, 1930
- visited Farnsworth
- saw demonstration of image dissector
Iconoscope
- electronic video camera tube
- used cesium and silver
- detect light
- create electronic charge
- pixels into mosaic
- more sensitive to light than image dissector
Kinescope
- electronic video projecting tube
  - cathode ray tube
- electronic signal
- electron gun
- illuminates phosphorescent screen
World of Tomorrow
- New York
- RCA Pavilion
- David Sarnoff
- television
  - introduced electronic television
  - transmitted by radio
1939 World’s Fair
Futurama
Suburbanization
- post-World War II
- flight from urban housing
  - rural farmland
- mass-produced housing
  - Levittowns, etc.
- Interstate highways
Television at Home
- initially they listened to radio
- away from downtown theaters
- families became more selective about entertainment
- television became domestic “window on the world”
National Television Systems Committee
- NTSC, group of electronics firms, including RCA
- analog standard TV for US, 1941–2009
- 525-lines
- 60 Hz (fields per second)
- interlaced: odd and even fields
- 30 frames per second
FCC Freeze
- instituted September 30, 1948
- “freeze” on new licenses
  - standard for color television
  - additional spectrum space
  - educational TV channels
  - reduction of radio interference
- lifted April 14, 1952
Color Format War
- CBS Color
- RCA Color
CBS Color
- four-color system
- introduced 1951
- not compatible with older B&W TV receivers
  - no image would display
RCA Color
- three-color system
- introduced 1953
- backward compatible with B&W receivers
- image would be in B&W
- FCC selected RCA Color for NTSC Color, 1954
Electromagnetic Frequencies
- cycle per second = 1 Hz
- 1 kilohertz (kHz) = 10³ Hz
- 1 megahertz (MHz) = 10⁶ Hz
- 1 gigahertz (GHz) = 10⁹ Hz
- 1 terahertz (THz) = 10¹² Hz
- 1 petahertz (PHz) = 10¹⁵ Hz
- 1 exahertz (EHz) = 10¹⁸ Hz
Television Spectrum
- Channels
  - 6 MHz of spectrum
- Very High Frequency
  - 30 MHz – 300 MHz
- Ultra High Frequency
  - 300 MHz – 3 GHz
Very High Frequency
- VHF low-band
  - channels 2–6
- VHF high-band
  - channels 7–13
- requires channel separation between adjacent channels
Ultra High Frequency
- UHF
- channels 14–69
- required less channel separation
- expanded available channels
UHF vs. VHF
- FCC decided intermixture of VHF and UHF frequencies
- FCC did not require TV sets to receive UHF stations until 1960
- Result:
  - VHF stations proliferated
  - UHF stations languished
Sales of TV Sets in United States
Rapid Adoption
Effect of Freeze
- TV networks from radio
  - NBC
  - CBS
- pre-Freeze stations
  - owned-and-operated
  - network affiliates
- UHF stations did not proliferate
Network Oliopoly
- CBS
- NBC
- ABC
Community Antenna TV
- Community Antenna Television, 1948
- rural Pennsylvania, rural Oregon, and Manhattan
  - terrain blocked TV reception
- distant signal importation
- considered piracy by broadcasters, until 1960s
Satellite Cable
- Satcom I, 1975
  - geostationary satellite
  - continental footprint
- launched cable networks
  - HBO and WTBS
  - Showtime, ESPN, Nickelodeon, Weather Channel
Multichannel Universe
- specialty channels
  - shopping channels
  - 24-hour news channels
  - pay-per-view
- timeshifting: VCR and PVR
- video-on-demand
- subscription streaming services
Superstation
- Ted Turner, WTBS
  - UHF TV station, Atlanta
  - expanded reach via satellite
- programming was like broadcast network
  - off-network reruns
  - syndicated program
  - no local programming