Also be wary of radio signal systems. These are usually made for timing distance runners in training. They work by the runner (wearing a transmitter) entering within x meters of the receiver. I think the margin of error can be significant. Not to mention radio signals (i.e. Bluetooth) being finicky.
Progression/regression in a flying 200M is measured within tenths of a second. If the margin of error is higher than that, then the system is useless.
Last edited by carleton; 05-15-16 at 04:52 PM.