Question 8-29D5

In a raster-type display, common in older CRTs (Cathode Ray Tubes) used in oscilloscopes, spectrum analyzers, and televisions, the electron beam systematically sweeps across the entire screen. It moves from left to right, then rapidly retraces to the left while moving down slightly, repeating this pattern until the bottom of the display is reached. This process, covering the screen both horizontally (lines) and vertically (fields/frames), creates a full image by illuminating individual pixels. * **A) From the center of the display to the outer edges:** This describes a radial scan, often used in some radar displays (like A-scope or older PPIs), not a raster scan. * **C) In a rotating pattern which follows the antenna position:** This is specific to a Plan Position Indicator (PPI) radar display, which is a specialized type of display and not a general raster scan. * **D) From one specified X-Y coordinate to the next:** This describes a vector-type display, where the beam only draws lines between specific points, rather than sweeping the entire screen area.