EMG sensor not working [SOLVED]

Using Arduino Sensors
1

I followed a tutorial (it's a short video so i will paste the URL here) : https://www.youtube.com/watch?v=0FsTPQY1bJw&t=181s&ab_channel=SaravananAL to get a reading of EMG sensor.
I have done everything as displayed. Plugged all the pins of both the EMG sensor and Arduino Uno board correcly, written the right code (i checked for other examples and tutorials and everyone is using this same configuration and code)
But once i plug the electrodes and open the serial plotter the only output is maximum value of 1023. I tried tweaking the onboard potentiometer but nothing happens.

I read somewhere that being the maximum supported Voltage value 5V for Arduino Uno boards and being the sensor powered by +9/-9V the Signal Pin output of the sensor it's too high in voltage for Arduino Uno to handle. So i tried dampering the signal between Signal Pin and A0 with resistances. I decreased it up to 3V but nothing changes. Still getting 1023.
It's odd considering how easy it seems in the tutorial. May my unit be damaged? How can i properly address the issue? Thank you for your patience

Solution:
The onboard potentiometer of the amplifier need tweaking as the default settings are max amplification and Arduino analog inputs can't handle the voltage (which is ~8V). So you have to tweak the potentiometer in order to stay in the 0-5V range. The first time i tweaked the potentiometer i worn it, so i couldn't figure it out the problem was that. I bought another sensor, tweaked the potentiometer easily, and it worked!

2

At 4:17 he says "You get maximum value when the probes are not attached (to your body)"
At 5:27 he writes "Idle condition is 1023"

3

Sorry i must have been unclear. value is always 1023, no matter if the electrodes are attached or not, moved or not, attached to a calf or an arm. The output is everytime 1023

4

From the video, I see "idle condition is 1023" and if your device always reads "1023" then the device is always seeing "idle condition" regardless of being attached and moving or not. From that I conclude the sensors, connecting wires, and pad material are not creating pulses for the analog pins to receive.

Try to make the pads produce noise. It might be that an amplifier is needed, as the pads might produce only microvolts.

5

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