How Police Radar Clocks Speeders
By Craig Peterson
Last updated: 2020
Radar can transmit continuously or be placed on hold, ready to fire but not transmitting. With no signal present there's nothing to detect, neutralizing radar detectors. When a target draws near, a button-press on the remote triggers the radar and a speed appears almost instantly.
Officer preference dictates the choice. Some let it run constantly, content to get fewer customers except for the brain-dead. Aggressive officers are more likely to use instant-on, hoping to outwit drivers with detectors.
A few radar models have POP mode where they transmit in bursts too short for a detector to spot. The feature works as advertised but legally, it can't be used as the basis for a ticket. For that the officer must place the radar in conventional mode, where it can be detected. Learn more.
Same Lane mode
Same Lane mode allows the officer to clock same-direction vehicles ahead of the rolling cruiser. If the radar has a second, rear-facing antenna it can clock faster vehicles as they approach from behind.
Fastest Speed mode
Radar clocks the strongest target within range, usually whichever is the closest. But a mix of cars and big trucks can confuse it. Although the red car in the photo is closer to the radar, the speed of the much larger beverage truck behind it would be displayed instead.
Fastest Speed mode allows the radar to sample multiple targets and show the speeds of the fastest vehicle (the red car) and the strongest (beverage truck). Using this feature it's possible to clock a motorcycle passing an eighteen-wheeler, an impossible feat for conventional radar.