What is the function of the Variable Range Marker on a radar display?

• A. A user-directed graphical line tool to indicate or measure a bearing on the radar display
• B. A user-directed graphical circle tool to indicate or measure a range on the radar display
• C. A mode where own ship stays in the center
• D. A stabilized heading input

Answer: (B)

The Variable Range Marker is a circular, user-adjustable range guide on the radar screen. You drag or resize the circle so its edge passes through a target, and the radius tells you the distance from your own ship to that target. Because the circle represents a fixed distance in all directions, it’s ideal for measuring range, not bearing. It’s typically centered on your own ship symbol on the display, unlike tools that indicate a specific bearing with a line. Other display options, like keeping own ship at the center or inputting a stabilized heading, are separate controls, not the VRM itself.