Quick Timer R8X is high resolution programmable timer. It controls 8-channel relay controller boards of National Control Devices. It's fit for lights control, science experiment, home automation, industry control, energy conservation and so on.
A simulation of a NYC Transit Authority train traveling by automatic signals with working stop arms. Working circuit drawings show how the signal system relays function while the train passes over track circuits.
The program suggests most interesting guessing with a technique of ancient Chinese hexagrams!