Would be great if hovering over the sigals (at least the digital ones) would show some statistic.
Proposal:

the width of the pointed segment from the last edge to the next same oriented edge defines the cylce time/frequency. The segment from the last edge to the changing edge and from there to the next changing edge are measured (beside their absolute width) relative to the whole cycle.
This should be disabled if the current segment is larger than some percentage (80?) of the viewport