i'm a cyclist. Some traffic lights aren't triggered by bicycles. What is the frequency of the AC signal in the coils imbedded in the road to detect cars? Could I build an RLC circuit about the size of my foot that would trigger the light? Knowing the actual frequency is critical to choosing the correct capacitor and inductor. Would a small coil size capture enough magnetic flux? Is there any other way to trigger the signal that I'm not thinking about?