The Development and History of Color Television   (Part 1)
The early stages of color television experimentation in America overlap the technological development of monochromatic television. Color television was demonstrated by John Baird as early as 1928, and a year later by Bell Telephone Laboratories. Experimental color broadcasting was initiated in 1940, when the Columbia Broadcasting System (CBS) publicly demonstrated a field sequential color television broadcasting system. This system employed successive fields scanned one at a time in one of the three primary colors; red, blue, or green. On the receiver end, a mechanical color wheel was used to reconstitute the primary colors in sequence to enable reproduction of the colors in the original scene. In their 1941 report confirming the National Television Systems Committee (NTSC) monochromatic standards, the Federal Communications Commission (FCC) noted the potential benefits of the CBS color system but concurred with the NTSC assessment that color television required further testing before it could be standardized.

Further refinement of color television was temporarily suspended during World War II. After the war, work on the development of color TV resumed, and engineers were able to design a system that would operate within the 6 MHz channel allocation that had been established for black and white service. In a hearing which began 26 September 1949, and lasted for 62 days, CBS petitioned the FCC for commercialization of their 6 MHz, 405 line, 144 fields per second field sequential color system. Due to the higher scanning rate, such a system was not compatible with the existing monochromatic standard.

The economic costs of adopting an incompatible system were a major factor in the FCC deliberations. If adopted, it appeared that consumers would carry the cost of modifying the existing two million monochrome receivers to follow the higher field-sequential scanning rates and reproduce color signal transmissions in monochrome. The projected costs of this modification varied, with a low figure of about $25. In addition, it was also argued that when broadcasters elected to begin color service, they would lose that portion of the audience had not yet modified their monochrome receivers.

At the hearings, work on several experimental electronic color systems designed to be compatible with the existing monochrome system was presented to the commission. Color Television, Incorporated (CTI) demonstrated their line sequential color system which assigned the color portion of the signal to the successive lines of the image. In the first field, the uppermost line was scanned in green, the next line in blue, the next in red, and so on until the first field was complete. The second field was scanned in a similar manner, and the combination of the two fields produced a complete picture in color. The system operated at 525 lines, and 60 fields a second, corresponding to the existing monochrome service. The Radio Corporation of America (RCA) demonstrated its dot sequential color system in which color is assigned to successive picture elements or dots of the image. With this system, each line of any field is composed of dots in the three primary colors. The scanning system for this color design, (525/60), was also identical to the existing monochrome standard. Both the CTI and RCA color system were formally proposed to the commission as potential standards. In addition to these proposals, preliminary development of several other color systems were also presented. To many of the industry witnesses appearing before the commission, the demonstrations and discussions indicated that a satisfactory compatible system could be developed in a reasonable period of time and they urged that a decision regarding color be postponed.

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