A dual-mode closed-loop measurement system (100) for capturing a transit time, phase, or frequency of energy waves propagating through a medium (122) is disclosed. A first device comprises an inductor drive circuit (102), an inductor (104), a transducer (106), and a filter (110). A second circuit comprises an inductor (114) and a transducer (116). A parameter to be measured is applied to the medium (122). The medium (122) is coupled between the first device and the second device. The first device initiates the transmit inductor (104) to query via inductive coupling to a receive inductor (114) on the second device via a first path. The inductor (114) triggers a transducer (116) on the second device to emit an energy wave that is propagated in the medium (122) and detected by the first device. The transit time of energy waves is affected by the parameter by known relationship.
