with laptimer, to calculate and record time for motorcycle racer
and bike racer.
They use infrared to send and receive sign, to start and stop
Turn on the transmiter, it can send sign all the time, when a
laptimer pass it, laptimer receive the sign, it start to record the
first circle time, then the laptimer pass it again, recive a sign,
it record the second circle time, and so on.
Their frequency is 940 nm, so any transmitter or laptimer use 940
nm frequency can work together with our transmitter and laptimer.
10m scope to send sign
If a driver uses two transmitters, it is possible to time from
point A to point B, like a drag race.&