BioSemi.nl

Hello,

We recently noticed a noisy signal from our active two AD box. When we are recording our AD box signal (without any channels connected to the box) we can see a noisier signal from plugs A, B and EXG (those we are routinely using during our experiments) than from plugs C, D, E, F, G and H (flat signal; never used during experiment).
This is an example of what kind of signal we have on plugs A, B and EXG :
http://img820.imageshack.us/img820/9599/noiseab.jpg
http://img546.imageshack.us/img546/1363/noiseexg.jpg

We are using our bisoemi EEG since last year and the signal was flat for every plug including A&B until now. Is it a technical problem ?

Thank you
Thomas

The channels with installed amp/ADC modules show baseline noise, the channels without modules show a flat line (no ADC output). Your system has always been this way (64+8 amp/ADCs installed), it's normal.

Best regards, Coen (BioSemi)

Thank you Cohen.
Another question : is there a way to reduce the gain and improve our signal/noise ratio ? Via "Analog input box" in ActiView ?
Thank you
Thomas

Please explain explain why decreasing the gain would in your view improve the S/N ratio.

Best regards, Coen