What type of signals are you expecting to see? Do you have any errors or specific issues with your hardware or software? This forum is for assisting with errors/issues you are running into or brainstorming for how to implement something. Can you give more details on what you are trying to do?
well, am excpecting to see EEG signal .... this is a new test can you verify for me please ??
PS: am using 3 electrode, an external amplifier board hooked to to A0,GND and 5V of arduino.
Do you have an oscilloscope to verify that the signal is correct? What kind of amplitudes are you expecting with this signal?
I am not familiar with EEG/ECG signals but from your last image it looks like your signal is clipping at 5V a little. What is the voltage range you are using on your device?