Arduino and EMG with OPAMP

Projects General Guidance
1

I am trying to make an EMG using the tutorial from this website DIY ECG Machine On The Cheap. I have the same OPAMP and everything. The only thing I am doing differently is instead of an audio jack I am hooking them to a multimeter + and -. I am not getting any kind of meaningful change in voltage. It goes to 0 when I touch the two electrodes together but nothing else besides that. Any ideas?

Once I get this working I want to basically make an on / off switch that will control an LED. how can I make the output from this circuit connect to an arduino ?

2

Do you mean EMG or ECG?

A multimeter won't be fast enough to pick up an EMG signal. And the noise in that circuit looks like it is bigger than the EMG portion of the signal would be.

If you are trying to do EMG, it is essentially the same amplification as EEG (but different filters) so I would start there.