An ambulatory electrocardiography monitor recorder optimized for capturing low amplitude cardiac action potential propagation, comprising: a wearable housing adapted to be coupled to a pair of electrocardiographic electrodes (38, 39) that are fitted for dermal placement along the sternal midline; and electronic circuitry provided within the wearable housing and comprising: a low power microcontroller operable to execute over an extended period under modular micro program control as specified in firmware; an electrocardiographic front end circuit interfaced to the microcontroller and configured to output electrocardiographic signals representative of cardiac activation wave front amplitudes, comprising: a signal lead operable to sense cardiac electrical potentials dermally through one of the electrocardiographic electrodes (38, 39); a reference lead operable to sense cardiac electrical potentials dermally through the other of the electrocardiographic electrodes (38, 39); and a reference generator comprising a pair of resistors (93a, 93b) configured to inject a driven reference containing power supply noise and system noise to the reference lead, the pair of resistors (93a, 93b) connected to a DC power source by a pair of connections through which the pair of resistors (93a, 93b) receive the system noise and power noise comprised in the driven reference, the signal lead further comprising a coupling capacitor and a protection resistor comprised inline with the electrocardiographic electrode (38, 39); non-volatile memory electrically interfaced with the microcontroller and operable to continuously store samples of the electrocardiographic signals throughout the extended period. a wearable housing adapted to be coupled to a pair of electrocardiographic electrodes (38, 39) that are fitted for dermal placement along the sternal midline; and electronic circuitry provided within the wearable housing and comprising: a low power microcontroller operable to execute over an extended period under modular micro program control as specified in firmware; an electrocardiographic front end circuit interfaced to the microcontroller and configured to output electrocardiographic signals representative of cardiac activation wave front amplitudes, comprising: a signal lead operable to sense cardiac electrical potentials dermally through one of the electrocardiographic electrodes (38, 39); a reference lead operable to sense cardiac electrical potentials dermally through the other of the electrocardiographic electrodes (38, 39); and a reference generator comprising a pair of resistors (93a, 93b) configured to inject a driven reference containing power supply noise and system noise to the reference lead, the pair of resistors (93a, 93b) connected to a DC power source by a pair of connections through which the pair of resistors (93a, 93b) receive the system noise and power noise comprised in the driven reference, the signal lead further comprising a coupling capacitor and a protection resistor comprised inline with the electrocardiographic electrode (38, 39); non-volatile memory electrically interfaced with the microcontroller and operable to continuously store samples of the electrocardiographic signals throughout the extended period. a low power microcontroller operable to execute over an extended period under modular micro program control as specified in firmware; an electrocardiographic front end circuit interfaced to the microcontroller and configured to output electrocardiographic signals representative of cardiac activation wave front amplitudes, comprising: a signal lead operable to sense cardiac electrical potentials dermally through one of the electrocardiographic electrodes (38, 39); a reference lead operable to sense cardiac electrical potentials dermally through the other of the electrocardiographic electrodes (38, 39); and a reference generator comprising a pair of resistors (93a, 93b) configured to inject a driven reference containing power supply noise and system noise to the reference lead, the pair of resistors (93a, 93b) connected to a DC power source by a pair of connections through which the pair of resistors (93a, 93b) receive the system noise and power noise comprised in the driven reference, the signal lead further comprising a coupling capacitor and a protection resistor comprised inline with the electrocardiographic electrode (38, 39); a signal lead operable to sense cardiac electrical potentials dermally through one of the electrocardiographic electrodes (38, 39); a reference lead operable to sense cardiac electrical potentials dermally through the other of the electrocardiographic electrodes (38, 39); and a reference generator comprising a pair of resistors (93a, 93b) configured to inject a driven reference containing power supply noise and system noise to the reference lead, the pair of resistors (93a, 93b) connected to a DC power source by a pair of connections through which the pair of resistors (93a, 93b) receive the system noise and power noise comprised in the driven reference, the signal lead further comprising a coupling capacitor and a protection resistor comprised inline with the electrocardiographic electrode (38, 39); non-volatile memory electrically interfaced with the microcontroller and operable to continuously store samples of the electrocardiographic signals throughout the extended period.