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Old 06-03-2011, 04:46 PM
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West West is offline
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Yes, Peter Goldmark, who invented the "chromacoder," as he called it, got GE to market a version of the system just after the approval of NTSC color in December of 1953.

A standard GE IO camera was modified with a small color wheel to create a field-sequential signal which was converted to standard NTSC in the chromacoder unit. Only one chromacoder was needed in a studio with several cameras, it was claimed, making the system even less expensive than RCA's three-tube monsters.

Without digital frame-store technology, Goldmark had to employ three small monochrome CRTs which were gated sequentially to display only one color's image from the sequential signal. Three C.P.S. Emitron pickup tubes then scanned the images off these tubes and fed the NTSC encoder in the chromacoder. These tubes had storage capability, which allowed the conversion.

The field-sequential portion of the system was scanned vertically, so as to avoid moire as much as possible. This is from Lloyd, C. G., “Chromacoder Colorcasting,” General Electric Company. (source and date unknown, I think a house technical journal, early 1954).

In William Paley's book, Paley, William S., As It Happened: A Memoir. New York: Doubleday, 1979, the CBS president relates a funny story of how he had a demo set up to compare a chromacoder camera with the RCA TK-40 and whether to continue supporting the program.

With Goldmark sweating bullets, as they say, Paley and the other CBS execs decided that the RCA camera simply made better pictures, and that was that! That was the end of the chromacoder. Evidently no chromacoder systems were actually sold anyway.
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