Tables of Contents
Why Understanding TV History Matters for Video Engineers
History Begins
Introdcution to Video Res
Conclusion
Why Understanding TV History Matters for Video Engineers?
Appreciating where we are today starts with knowing where we came from. Understanding TV history is crucial becasue it didn't really start with TV's but with broadcasting and it provides valuable insights into the technological advancements, evolution of standards, and problem-solving techniques that shape modern video engineering (all of which we can still learn from today).
History Begins
Understanding the origins of television begins as early as broadcasting.
Broadcasting was pushed by the government to disseminate information, but it was driven by inventors, commercial business, and the public's thirst for information and entertainment.
Keypoints
Broadcasting started on November 2, 1920
November 2, 1920, marked a significant milestone in broadcasting history
1920s-1930s: The Drive for Innovation
Fast forward to the 1930s
At this stage,
Quick Overview Rundown
In the 1930s, development and experimentation...
May 2, 1941:
1953:
The transition
1990s:
1996:
Late 1990s - 2000s:
2006
June 12, 2009
1. Broadcasting started on November 2, 1920, with a radio station called KDKA in Pittsburgh, Pennsylvania. Can you believe it? Not even video, but audio. The station was established by Westinghouse Electric Corporation, a company founded by George Westinghouse, who was born on October 6, 1846, and died on March 12, 1914. Frank Conrad, an engineer at Westinghouse, played a pivotal role in setting up KDKA and conducting the first commercial radio broadcast.
2. November 2, 1920, marked a significant milestone in broadcasting history as it featured the first-ever commercial radio broadcast, which covered the presidential election results, allowing the public to receive timely updates.
3. 1920s-1930s: The Drive for Innovation
Inventors and engineers in the 1920s and 1930s, were driven to improve picture and sound quality to meet technological challenges, capitalize on commercial opportunities, satisfy growing public demand, adhere to government regulations, and outcompete rivals in a rapidly evolving industry.
4. Fast forward to the 1930s There where two type of TVs, mechanical scanners (released to consumers in the late 1928's) and cathode ray tubes (CRTs) (released to consumers in the early 1930's). They were the first two consumer types of TVs and worked by scanning broadcast signals. Mechanical scanners used a rotating disk with holes to scan images, while CRTs used electron beams to create images on a phosphorescent screen.
5. At this stage, television quality was defined by the number of lines used to form an image, rather than the resolution as we understand it today. Early mechanical TVs could have as few as 30 lines, producing very basic images, whereas CRTs started to increase this number, enhancing the image quality significantly.
6. Quick Overview Rundown:
1920s-1950s: Early TVs used line-based measurements for image quality.
1980s-1990s: Introduction of digital video technologies and the gradual shift to pixel-based resolution.
1990s-2000s: Establishment and adoption of digital broadcasting standards and HDTV, solidifying the use of pixel-based resolution.
7. In the 1930s, development and experimentation with interlaced scanning technology began.
Technological Advancements. Cathode Ray Tube (CRT) Development: The CRT technology, which became the foundation for television displays, was being refined during this period. The need to improve image quality and reduce flickering in CRT displays led to the exploration of interlaced scanning.
Bandwidth Efficiency Limited Bandwidth: Early television broadcasts faced significant bandwidth limitations. Interlaced scanning was developed as a solution to improve image quality without requiring more bandwidth. By displaying alternate lines of the image in two successive fields, it effectively doubled the perceived frame rate and reduced the bandwidth needed compared to progressive scanning.
Standards Development Broadcast Standards: As television technology evolved, there was a push to establish standardized formats for broadcasting. The interlaced scanning method was seen as a way to achieve higher resolution and smoother motion, making it an attractive option for emerging television standards.
Early Pioneers and Experiments: Research and Prototypes: Engineers and inventors conducted various experiments with interlaced scanning throughout the 1930s. These efforts culminated in the practical implementation of interlaced scanning in early television systems, setting the stage for its inclusion in formal standards like the NTSC.
8. May 2, 1941: The National Television System Committee (NTSC) standard was formally adopted in the United States. This standard included the use of a 525-line interlaced format with a frame rate of 30 frames per second (60 fields per second).
9. 1953: The NTSC color television standard was introduced. This standard maintained the 525-line format but added color information, making it backward compatible with black-and-white TVs.
10. The transition from using "lines" to "resolution" in terms of pixels occurred primarily during the shift from analog to digital television.
11. 1990s: The development of digital television technology began to take shape, setting the stage for a significant shift from analog to digital formats. This era saw the introduction of various digital video formats, leading to higher image quality and the adoption of pixel-based resolution standards.
12. 1996: The Advanced Television Systems Committee (ATSC) established new digital television standards in the United States. These standards introduced various high-definition television (HDTV) formats, such as:
720p (1280x720 pixels, progressive scan)
1080i (1920x1080 pixels, interlaced scan)
1080p (1920x1080 pixels, progressive scan)
13. Late 1990s - 2000s: Television manufacturers and broadcasters gradually adopted ATSC standards, producing digital television sets and starting digital broadcasts alongside existing analog broadcasts.
14. 2006: The Federal Communications Commission (FCC) set a deadline for the transition from analog to digital television broadcasting.
15. June 12, 2009: The final deadline for the cessation of full-power analog television broadcasts in the United States. After this date, NTSC analog broadcasts were no longer transmitted by full-power stations, marking the effective end of the NTSC era in the U.S.
Conclusion
Understanding TV history is essential for video engineers because it highlights the technological advancements and problem-solving techniques that shaped modern video technology. This knowledge provides valuable insights and lessons, helping engineers build on a solid foundation as they continue to innovate.
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