An ambulatory, electrically-powered device designed to be connected to a thorax-placed electrode array (not included) to collect, process, and wirelessly transmit signal data pertaining to a cardiothoracic physiological parameter [e.g., respiration rate, electrocardiogram (ECG)] for subsequent display on a separate monitor. It is a small unit, with electrode connecting cables, designed to be carried/worn by the patient (e.g., attached to a belt). This is a reusable device.