A health-monitor patch comprising at least one physiological sensor and digital processor is configured to be adhered to the skin of a subject. A health-monitor patch may further include an accelerometer and may detect cardiac waveforms, activity performed by the subject, and a body orientation of the subject. A health-monitor patch may be disposable, in some embodiments, and used fox outpatient monitoring. Aspects of noise cancellation and reel-to-reel manufacturing are also described.