  The development of single-electron sources has paved the way for a novel type
of experiments in which individual electrons are emitted into a
quantum-coherent circuit. In one approach, single-electron excitations are
generated by applying Lorentzian-shaped voltage pulses to a contact. Here, we
propose to use such voltage pulses for electronic spectroscopy of mesoscopic
devices. Specifically, we show how characteristic timescales of a
quantum-coherent conductor can be extracted from the distribution of waiting
times between charge pulses propagating through a mesoscopic circuit. To
illustrate our idea, we employ Floquet scattering theory to evaluate the
electron waiting times for an electronic Fabry-P\'erot cavity and a
Mach-Zehnder interferometer. We discuss the perspectives for an experimental
realization of our proposal and identify possible avenues for further
developments.
