Radar speed signs are effective in slowing cars down, particularly with today’s highly visual, often distracted drivers. Also called speed display signs, driver feedback signs, and “your speed” signs, radar signs operate based on the feedback loop theory: when we are presented with information about our performance, we tend to notice and improve. Extensive research has proven that feedback loops affect real and positive change on people’s behavior. Speed radar display signs have been shown to slow drivers an average of 10%, usually for several miles. Using our radar speed signs.