Opto-coupter and electric circuit of EEG-SMT

[Konstantin]

Hello!

Can anyone explain me please? There written about opto-coupter: http://openeeg.sourceforge.net/doc/modeeg/modeeg_design.html
Where Is it on electric circuit of EEG-SMT?

Best regards.

[LubOlimex]

Hello Konstantin,

There is no such an opto-coupler in latest revisions of EEG-SMT. Instead of such we use ISO7221XD (U3) - dual digital isolator.

Best regards,
Lub/OLIMEX

[Konstantin]

Thank you for the answer!

[Konstantin]

Another question:

It is about EEG-SMT from here: https://www.olimex.com/Products/EEG/OpenEEG/EEG-SMT/
CH1+ and CH1- are for the electrodes of one amplifier channel from here: http://openeeg.sourceforge.net/doc/modeeg/modeeg_design.html
("Simplified block diagram of the ModularEEG amplifier"). CH1+ and CH1- are for observing of the voltage difference between two points on the scalp.
Am I right?

[LubOlimex]

Yes. That is why it is good idea to place  both electrodes of one channel symmetrically across the skull.

Best regards,
Lub/OLIMEX

[Konstantin]

Great! Thank you!