TIA 1A - TELEVISION INTERFACE ADAPTOR (MODEL 1A)

10. Color Phase Shifter

This portion of the chip (shown in figure 3) produces a reference color output (color burst) during horizontal blank and then during the unblanked portion of the line it produces a color output shifted in phase with respect to the color burst. The amount of phase shift determines the color and is selected by the four color code lines from the Color-lum multiplexer. Binary code 0 selects no color. Code 1 selects gold (same phase as color burst). Codes 2 (0010) through 15 (1111) shift the phase from zero through almost 360 degrees allowing selection of 15 total colors around the television color wheel.

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