An assembly of devices used to non-invasively detect, measure, and display bio-magnetic signals produced by electrically-active neural tissue of the heart that provide diagnostic information about cardiac electrophysiology (EP) [magnetocardiography (MCG)]. It typically consists of a fixed or moveable gantry, a patient table, a dewar [vessel containing liquid helium (He)], dedicated software, and a superconducting quantum interference device (SQUID) sensor array that measures the magnetic fields created by electrical current flowing with neurons. It may be sited within a magnetically-shielded room (MSR), and is used for cardiac mapping and the diagnosis of heart disorders.