A standalone light gate system that requires no separate timer or complex wiring setup. The ‘master’ light gate connects via Bluetooth to any tablet or PC running Timing-Pro software and the inbuilt rechargeable battery can provide power for an unlimited number of slave light gates (which connect by a single lead) or for the separately available g by free fall release mechanism. Ideal for use linear air tracks and dynamics ramps/cart. Determination of g by free fall can be performed in a number of ways using 1 light gate or 2 light gates in conjunction with the Timing-Pro g by free fall stand and solenoid.