Finish time control only knows at what time you crossed the finish line. Since everybody uses synchronized clocks to the 1/100th of a second you can compare start and finish times to know your stage time. Start control logs all the start times for all cars and finish logs all the finish times. Scoring uses those logs to double check the validity of the time cards. Note that there is a person sitting at the finish line to observe which car crossed the line at what time, they communicate the time over the radio to the people at finish time control so that they can write the time on the timecard. When you use a system like rallysafe, they use the GPS signal of the unit when you crossed the line to automatically record the time. If it's a small local event, there is someone sitting at the line with a timing clock that they press when you cross the finish line. You can also use timing equipment with a laser beam but they don't work very well in dusty environments, you get a lot of false triggers.
@@FrogRacing I see thanks. Im just used to watching the clock on wrc. I was always wondered how they know the minutes they pass the red board. GPS helps
