🏁 Transponder
A small device on the car that a track's timing loop reads to record laps and times automatically.
RC Crash Crew race results also work by manual entry — no transponder required.
What it actually does
A transponder is the small device in your car that the timing system uses to identify you as you cross the loop. It is what turns a race into lap times, positions and results rather than people counting laps by eye.
In practice
Some are personal transponders you own and carry between cars, others are rented by the club for a meeting. Personal ones are registered to you so your number follows you. Mounting matters — the system needs a clear path to the loop in the track surface.
Worth knowing
Follow the mounting guidance for your system, keep the transponder away from the ESC and motor wiring, and check it is powered. A car with a badly mounted transponder shows up as missed laps, which is impossible to fix after the race.