From: frans (f.smith_at_c...)
Date: 2001-06-28 23:26:22
Hi Lovass, and all,
I did not yet build the HAL-4, but i was thinking.
The Hal - 4 may be old, but then would it not be
possible to make use of (sensor) pre-amps ?.
So the analog signal from the brain is pre-amplified.
I saw somewhere on the net, sensors with some sort
of pre-amp, although miniature component (smd)
build together with the sensors.
Also, could whe not use the same technique pre-amp/sen-
sor for the rs232 ?.
The use of adio leads, like the HAL, is not so bad at all.
My one-channel-waverider-CEO uses simple (low-cur-
rent) leads, but lab-instruments seems to have shielded
leads.
Frans.
----- Original Message -----
From: "Lovass Laszlo" <prochess_at_e...>
To: <buildcheapeeg_at_yahoogroups.com>
Sent: Friday, June 29, 2001 11:11 AM
Subject: [buildcheapeeg] bandwith idea
> Hi,
>
> An idea has crossed my mind: what if using a rate of 256 samples/sec and a
> freq band DC to 100 Hz (lowpass point here) and also using a reference
> channel for detecting noises (like muscle impulses, radio freq, 50/60 Hz
> buzz, etc.) and subtract it in the amplifier section.
>
> The possible advantages: getting rid of phase and amplitude distorsion,
> possible use of gamma and even higher brainwaves (cf. 35-45 Hz brainwave
> research of visual observations, etc.).
>
> Any comments?
>
> Regards,
>
> Lovass Laszlo
>
>
>
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This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:31 BST