Olimex Support Forum

Others => Biofeedback - EEG, ECG, EKG => Topic started by: spot on December 17, 2012, 03:16:34 am

Title: Active or passive electrodes for the EEG-SMT?
Post by: spot on December 17, 2012, 03:16:34 am
Hi,
I have read that both will work, but how do I decide whether to use active or passive electrodes?
Thanks
Title: Re: Active or passive electrodes for the EEG-SMT?
Post by: LubOlimex on December 17, 2012, 01:46:00 pm
Hey spot,

The active electrodes resist surrounding noises better. However, the passive electrodes are completely reliable for first steps/tries with EEG-SMT.

Best regards,
Lub/OLIMEX
Title: Re: Active or passive electrodes for the EEG-SMT?
Post by: Ruben on January 20, 2013, 03:09:23 am
Hey Lub,

I have any problems to get a good signal. I´m getting an artefacted signal every time. I´ve followed your and Kris´suggestions but I havent got a good signal. Do you know any way to solve this problem? Do you think that it´s possible to use an other kind of electrode??

Thank you very much
Title: Re: Active or passive electrodes for the EEG-SMT?
Post by: LubOlimex on January 21, 2013, 04:18:39 pm
What kind of artefcated signal, Ruben? Is it very steep line or is it updating slowly? Did you try with all three supported software tools (mentioned and explained) in the manual?

Is it possible to use laptop (that is currently not plugged into the electrical network) to do your tests? Does the signal improves?

EEG-SMT is sensitive device - sometimes dust can be problematic or electrodes with left-over gel can make poor contact. Ensure the device is well-cleaned with a soft cloth and maybe a bit of alchohol.

Best regards,
Lub/OLIMEX
Title: Re: Active or passive electrodes for the EEG-SMT?
Post by: Ruben on January 23, 2013, 03:05:56 am
Hey Lub,
How are you??

This is, mainly, an electric artefact. SOmetimes, I get reduce this noise (I have a grounding installed by an ingenieer and that does it. Did i send you some photos of this issue?? i dont remember it...). I get a poor signal power too, in some times. I´m sure that the equipment is correct, but i cant make it work correctly. I´ll try to put less conductive paste.
Thanks you for your answer.
I´ll tell you my progress.

Thanks

Rubén