Connecting electrodes to the board (Cyton & Daisy)
masteroforest
Russia
in Cyton
Hello!
I connected the electrodes to the board randomly to test the interface.
Our helmet has the following outputs:
FP1, FP2, GND, FZ, CZ, REF, PZ, O1, O2, F7, F3, C3, T3, P3, T5, F8, F4, C4, T4, P4, T6.
Our board has the following inputs:
AGND, BIAS, N1P...N8P, SRB (top and bottom row on each board).
There is also a Y-Splitter Cable (2 in 1).
Please tell me how to properly connect the outputs to the inputs.
And how to use a Y-Splitter Cable (2 in 1)?
I did not find information about this.
Regards,
Dmitriy
Comments
https://docs.openbci.com/docs/01GettingStarted/01-Boards/DaisyGS
Thank you for your reply.
I figured out where to connect 16 channels. But a lot of questions arose about control points.
Our kit does not include an ear clip. It is also not clear where the bias connects. If also to the ear, then you already need 2 clothespins.
There are 5 electrodes on our helmet along the central: GND, FZ, CZ, REF, PZ (image attached). Can these electrodes act as the first and second reference points?
In addition, an unused AGND connector remains on each board. Why is it needed?
Dmitriy, hi.
Technical name for such device is EEG electrode cap. The word 'helmet' might be confused with 'headset', which is generally a plastic based framework holding electrodes in position. Caps are generally elastic cloth based.
You can place reference (SRB2) and Bias (called 'Ground' on some equipment) on any of your unused midline 10-20 positions. On most caps, AFz is used as a ground connection. But it can be anywhere.
If your cap has labeled locations for REF and GND, then yes, you can connect SRB2 and Bias to those.
Note that EEG recordings made with a given reference location, can always be "re-referenced" in software.
https://www.google.com/search?q=eeg+re-referencing
Regards, William
The AGND pin is left unused. It is intended to only be used in certain upcoming applications, such as "active electrodes".
Hi!
Will, thanks for the explanation and for the link to "re-referenced".
Now it's all clear. I already connected electrode cap. Yes, and now I will correctly call my equipment EEG Eletrode Cap)
Regards,
Dmitriy