Electrocardiography for Cheap: DIY ECG Uses One LM741 Op-Amp, Five Resistors, and 'Penny Electrodes' « Adafruit Industries – Makers, hackers, artists, designers and engineers!
Build DIY ECG Monitor with Digilent Analog Discovery Studio and NI LabVIEW -
Build Your Own ECG-EKG Unit | Nuts & Volts Magazine
Another ECG Question thread (Using FFT, low pass filter) - Project Guidance - Arduino Forum
Electrocardiography for Cheap: DIY ECG Uses One LM741 Op-Amp, Five Resistors, and 'Penny Electrodes' « Adafruit Industries – Makers, hackers, artists, designers and engineers!
ECG Project With All The Messy Safety Details | Hackaday