#460Radar Sweep

A PPI radar scope: a sweep arm rotates over a phosphor-green field, dragging an exponentially decaying trail behind it across concentric range rings, bearing ticks and N-S-E-W crosshairs. Fixed contacts ping bright the instant the arm passes and fade in its wake, hostile returns glowing amber with an expanding ripple. Scroll spins the sweep faster, the pointer recentres the plot, and pressing boosts the receiver gain.