As motorists approached a white trailer beside a road in Irvine on Friday, their driving speeds suddenly flashed from it in large, orange-neon numbers.
The trailer, the Irvine Police Department's latest weapon in the fight against speeders, carries the state's first unmanned, solar-powered, radar display sign, said Irvine Lt. Robert Lennert.
It is hoped that the traffic control unit will serve as a gentle reminder to drivers who go faster than the posted speed limit.
"About 80% of them don't really speed on purpose," Lennert said. "They are usually honest people."
The trailer, which is moved to different locations each day, was first put into use in June, but police officially announced its existence Friday as part of a citywide effort to discourage traffic violators.
The trailer, which was built by the city for about $3,500, is intended to slow traffic in certain residential areas, reduce ticketing and free officers for other police matters, Lennert said.
With no police unit stationed near the trailer, Lennert said, police officials hope that most drivers will slow to a safer speed when they see the sign. So far, he said, it seems to be working.
Police officials first approached the Public Works Department in the spring to design the trailer in response to frequent complaints from residents that drivers often speed through Irvine, endangering pedestrians and property.
At first, patrol units were stationed along several of the city's major thoroughfares, such as Barranca Parkway, Michelson Drive and Alton Parkway, to issue citations and warn drivers to maintain the speed limit, Lennert said.
But that approach proved too costly and took many police cars off regular patrols. The trailer, using a radar gun mounted next to a digital display monitor, can detect the speed of cars as they approach from 800 feet, Lennert said.
A second radar sign is expected to be in operation by the summer, he said.