Traffic lights are timed using a few different methods, with many using inductive loop systems embedded in the road in order to function properly. Induction loops are basically magnetic sensors ...

Such a situation faced [David Schneider] at his Quaker meetinghouse, which he ended up solving with this home-brew audio induction loop system. The worship style of conservative sects of the ...

For anyone unfamiliar with the original project, the circuit detected a vehicle via an inductive loop and was able to perform a task like opening a gate. It now has two independent channels which ...