Dear all,
When switching in the OpenBCI_GUI from 8 channels to 16 channels by using the Daisy board a 25Hz sub-harmonic is introduced besides the 50Hz harmonic. Did more people encounter this?
Best regards,
Sjoerd
Depending on the EMF (electromagnetic field) environment around your setup, different Cyton configurations (with / without Daisy), may 'couple' into the local fields in different manners. Are you using a Notch filter at 50 Hz? That should eliminate both the 50 Hz and any harmonics.
Other EMF considerations, in general are: avoid extension cords, power supplies, AC lamps, conduits in walls / floors / ceilings, etc. Also be aware of close proximity to routers, repeaters, cellular emitters. There are "EMF meter" applications that may work on your phone to point out local field intensities. There are also stand alone EMF meters that are generally more sensitive. The phone EMF meter apps require that your phone contains a magnetometer chip. Which less expensive phones usually omit.
Comments
Sjoerd, hi.
Depending on the EMF (electromagnetic field) environment around your setup, different Cyton configurations (with / without Daisy), may 'couple' into the local fields in different manners. Are you using a Notch filter at 50 Hz? That should eliminate both the 50 Hz and any harmonics.
Regards, William
Other EMF considerations, in general are: avoid extension cords, power supplies, AC lamps, conduits in walls / floors / ceilings, etc. Also be aware of close proximity to routers, repeaters, cellular emitters. There are "EMF meter" applications that may work on your phone to point out local field intensities. There are also stand alone EMF meters that are generally more sensitive. The phone EMF meter apps require that your phone contains a magnetometer chip. Which less expensive phones usually omit.