ECG simulation

        I have played with ECG collection for a while before. At the beginning, I used the AD8232 module. I worked on electronics by myself in my room every day. No one was lying down to test it for me. So you have to attach sticky electrodes, and the electrodes can easily fall off when you sit and wear clothes, so you have to work shirtless, which is very troublesome. So I have been thinking about whether there is a circuit that can help me complete this test, so I found this circuit. In fact, its principle is quite simple. I'll write it in detail when I have time. One switch is for power, and the power input is 5-9V. The other switch is for switching the heart rate, with two options: 60 and 120 times. The PCB is adapted to the three electrode interfaces of the small red AD8232 module on a certain product (the AD8232 module is connected to a 3.3V power supply). You can see the following waveform by hanging the oscilloscope on the OUTPUT of the module. The components are quite cheap, so you can copy them and play with them.