  We report microwave impedance measurements of a superconductor-semiconductor
hybrid nanowire device with three terminals (3T). Our technique makes use of
transmission line resonators to acquire the nine complex scattering matrix
parameters (S-parameters) of the device on fast timescales and across a
spectrum of frequencies spanning 0.3 - 7 GHz. Via comparison with dc-transport
measurements, we examine the utility of this technique for probing the local
and non-local response of 3T devices where capacitive and inductive
contributions can play a role. Such measurements require careful interpretation
but may be of use in discerning true Majorana zero modes from trivial states
arising from disorder.
