Re: [buildcheapeeg]new input stage, eagle files

From: peterson_at_d...
Date: 2001-05-21 18:19:19


--- In buildcheapeeg_at_yahoogroups.com, "Joerg Hansmann" <info_at_jhansmann.de> wrote:
> Hi,
>
> ----- Original Message -----
> From: <jiva_at_humboldt1.com>
> To: <buildcheapeeg_at_yahoogroups.com>
> Sent: Sunday, May 20, 2001 8:43 PM
> Subject: Re: [buildcheapeeg]new input stage, eagle files
>
>
> ...
> > 2) i wonder if the choice of electrodes might influence
> > the issue?
>
> Different electrode types might have different impedances, because.
> R and C parts of the impedance will vary depending on electrode
> area, material and used electrolyte / conductive gel.
>
Sometimes it's hard to get the same impedance out of the same
electrode on two different scalps, or even on 2 different spots on
the same scalp.

> However due to the high input impedance of the eeg-amplifier
> different electrode impedances should not lead to different
voltages.
>
> So the input voltage range will essentially be the same for all
> suitable electrode types.
>
> Regards,
>
> Joerg



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