Background
PhysioBank is an online physiologic signal archive. Many types of digitized signals (including ECG data) are available for free download.
A 60-second 12-lead ECG recording (16-bit resolution, 1000 Hz sample frequency) was downloaded from the site. MATLAB was used to scale the aVR and aVL signals, and then to write the data to a WAV file. The left channel of the WAV file contains aVL and the right channel contains aVR. Because aVL and aVR are augmented versions of the left arm voltage and right arm voltage, respectively, they can be used to simulate Lead I of the ECG.
How to use ecgwav.wav to test your electrocardiograph
Plus a modified headphone cable into the line-out of your computer. It is probably on the back and is green. The other end of the cable is split into three wires, black, white, and green, corresponding to the standard ECG wire colors.
Plug these wires into your breadboard at the appropriate places. (Note: do not use a DRL circuit to drive the green wire.) Download the ECG WAV file to your computer (right-click and save as) and play it with nearly any media player (e.g., Windows Media Player). The file lasts 60 seconds so you may wish to set the media player to repeat. The voltage will most likely cause your ECG to saturate. To remedy this, lower the volume in both the media player and the system controls. (On a Windows computer, lowering the Wave volume to nearly zero worked well.) Adjust the volume until the output of your ECG is an appropriate amplitude.
