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I have a minor issue with my ECG. When I poke at the leads, I get a reading. But when I hold the leads or place it near my heart, I don’t get anything. I’m pretty sure this is hardware related, but I don’t want to completely rule out a potential software problem. I used this YouTube video as a guide: https://www.youtube.com/watch?v=NDjRg-KgIXY, with their circuit show below.
My breadboard almost looks exactly the same as that, but with a couple of changes. Instead of connecting the ECG to the computer via a audio cable, I used Bluetooth to transfer it to my phone. Here is my schematic diagram.
Here is my breadboard diagram.
In my breadboard, I used three LM358 op-amps. Here is my Arduino code (if you need it):
const int signal = 7; // Pin
connected to the filtered signal from the circuit unsigned long currentBeatTime; unsigned long previousBeatTime; unsigned long frequency;
// Internal variables unsigned long period = 0; int input = 0;