Digital, multi frequency, integrated experimental timer designed specifically for mechanics experiments in middle and high schools. Accurate measurement of average velocity, instantaneous velocity, and acceleration can be achieved simultaneously on the same paper tape. Experimental case: Slope car, frequency modulation 50 Hz continuous dot, acceleration calculated by difference method; Free fall, set a high frequency of 100 Hz, record the plot for the first 0.3 seconds, and measure g. Instantaneous velocity demonstration, frequency conversion mode automatically sets double points at 30 cm and 60 cm, and directly reads v=Δ s/Δ t; Collision experiment, place Hall switches in the positions before and after the collision, record the time difference between the two stages, and calculate the recovery coefficient.