RCA later Harris RCA CA 3217 TV Chip. free download

File name rca_ca_3217_luma_chroma_tv_chip_info.pdf

ICAN-7175 Integrated NTSC Chrominance/Luminance Processor L.A. Harwood and E.J. RCA Labs, Princeton, N.J. Wittman, J. Hettiger and R.L. Shanley, RCA Consumer Electronics, Indianapolis, IN An intensive engineering effort in the past decade produced chrominance signal is gain controlled by an automatic color TV receivers with a high degree of maturity. Although chroma control (ACC) and overload detector and by a the price of receivers remained essentially unchanged, their customer-operated saturation control. A separate control performance and were improved substantially. reliability tracks the gain of the luma and chroma amplifiers and Among the many improvements in all sections of the serves as a customer-operated picture control. The viewer receiver are not only those that relate to a better picture sets the hue by means of a control; an automatic dynamic quality but also those responsible for reduced energy flesh-correction circuit maintains proper flesh color without consumption, the simplified operation of controls, and noticeably affecting the three primary colors. The luminance reduced weight. In this Note attention will be focused on peak-to-peak level is. set by a previously described picture improvements in the chroma/luma area. control; a comparator circuit sets the black level to a potential set by a viewer-operated brightness control. A brief historical review is appropriate for a better under- Picture and brightness levels are also controlled by an standing of the RCA CA3217E integrated circuit developed for this application. Ten years ago vacuum tubes were still automatic beam limiter. A signal derived from the kine- used in many color TV receivers, as efforts to fully beam current reduces first the picture amplitude to a transistorize receivers proved too costly. At first integrated predetermined level and then operates on the brightness control to prevent excessive drive to the picture tube. The circuits, primarily in the sound area, were not readily accepted, mainl