(Other people have, 3 days ago)
So I just ordered myself a "Shield-EKG-EMG" from Watterott.
I managed to get my heatbeat.
(That's the easiest you can do.)
Next step shall be tests of Electro Oculography (electric eye tracking).
Just some notes for myself:
EOGSignal is in the range of 1mV peak to peak .
Eye-blinking artifact is very strong.
50Hz line noise must be removed (of cause). (notch fiter)
low-frequency cutoff to 0.02 Hz
high-frequency cutoff 50Hz