Police and radar detector owners are engaged in a war of technology, and the police are making the next move - a radar-detector detector.

The police, according to an article in Esquire magazine, are testing the VG-2, which picks up microwaves that leak out of the oscillators in radar detectors.If the VG-2 becomes standard gear, it will be up to someone like Dale Smith to come up with the next generation of detectors.

Smith is the research scientist who was unjustly collared in a speed trap near Cleveland in 1968. He went home and built the world's first radar detector - the Fuzzbuster.

Today more than 10 million radar detectors cruise America's highways.

"It isn't speed demons who buy them," Smith said. "It's drivers who've been given tickets they didn't deserve."

In principle, radar is an ingenious police tool. The trooper sits in his car aiming a radar gun down the highway. The gun emits a microwave beam that bounces off approaching vehicles and reflects back to the radar unit at an altered frequency.

By measuring the change in frequency, the trooper calculates the speed of the oncoming vehicle. The trouble is the radar beam fans out like a searchlight. At a distance of 1,000 feet it's as wide as the highway itself. This makes it difficult for the trooper to know for certain which vehicle he's tracking.

In addition, the reading can be thrown off by operating errors or by interference from power lines or neon lights. As many as 30 percent of all radar-generated speeding tickets are given in error, according to some estimates.

In 1979, a Miami television station showed a police radar clocking a house going 28 mph and a banyan tree doing 86.

Radar detectors are very much like FM receivers. They can pick up radar signals more than a mile from the source, at which distance the beam is too weak to bounce all the way back to the police car but strong enough to make the detector beep.

Insurance companies are vociferous opponents of radar detectors. They want the federal government to ban them, as Virginia, Connecticut, New York and Washington, D.C., have done.

They say vehicles are two to three times more likely to exceed the speed limit by 10 mph if they have radar detectors - and detectors are used by 4 percent of all passenger vehicles.

The pro-detector people cite a 1987 Yankelovich study that indicates detector owners are more responsible drivers than non-owners. They have 23 percent fewer accidents per mile, and they use seat belts more often. Detector buffs also point out the rate of highway fatalities has declined steadily.

Bobby Unser, three-time winner of the Indianapolis 500, who has been unjustly nabbed for highway speeding, said:

"Traffic tickets are a form of taxation. They have nothing to do with safety."

Unser is part-owner of a company that makes Trident, an information console that combines a radar detector, a police-radio scanner and a CB-radio receiver.

The police could use a wide range of non-radar surveillance techniques, including laser scopes and high-tech methods of visual sighting.