Red Screen

[whikgd]

All the connecting seems very good, but why there are so many noisy and the screen even becomes red!

[Coen]

Start with making sure that the blue light (CM in range) is continuously ON.

One or more electrodes do not make proper electrical contact with the subject skin, and are flapping rail-to-rail due to interference pickup.

Identify to problem sites in the offset tabpage. Most probably cause is lack of electrode gel in the holder. Add gel and if needed, gently work the gel between the hairs with the plastic tip of the syringe.

Best regards, Coen (BioSemi)

[whikgd]

The blued light is okay.
Can I test just using several electrodes? I try to test by 3 electrodes and all were connected well but still didn't get better data on screen.

[Coen]

You can test with only a few electrodes. Select only the connected electrodes in the display (use "free choice" option), the loose hanging electrodes will show large interference signals, making the connected electrode invisible. Select the proper Reference to achieve sufficient Common Mode rejection (e.g. average of connected/displayed electrodes).

Best regards, Coen (BioSemi)