Nearly all modern racing cars and motorcycles carry electronic transponders which relay precise timing information down to the thousandths of a second.

A system of electronic transponders called EZ-Passes, introduced in the 1990s, has reduced congestion at toll plazas but hasn't eliminated it.

Under the new system, called E-Z Pass, drivers who sign up will have an electronic transponder on the windshield.

Lower charges are levied on frequent 407 users who carry electronic transponders in their vehicles.

It showed that the plane's electronic transponder was turned on and was emitting a four-digit coded signal for civilian aircraft.

An electronic transponder is mounted on the windshield of a car.

He is wearing electronic "transponders" on his wrist and ankle, is under 24-hour supervision, and cannot leave the camp at all for now.

This system would require the fitment of special electronic transponders to each bus in order to alert traffic signals.

"An electronic transponder built into her superstructure," Hadley said.

I-Pass is the Illinois Tollway's electronic transponder toll collection system that allows drivers to pre-pay their tolls.