From: Jim Meissner (jpmeissner_at_mindspring.com)
Date: 2001-11-30 13:32:26
Doug Sutherland wrote:
> 3) Jim has achieved results far superior to all
> other low-cost EEGs I have seen, band width
> is 0.1-100 HZ with sampling at 120 Hz. This
> is better than all of the low-cost EEGs I
> have seen including commercial ones like
> WaveRider, Brainmaster, POD, etc.
A response of 0.1-100Hz is not possible when sampling at 120Hz. In
theory the maximum is 60Hz, but even then detection of a 59Hz signal
would be rather unstable (going in and out of phase with the sampling
frequency). I like the recommendation you quoted from the "IFCN
Standards" of using a higher sampling rate, say 200Hz.
Dear Jim Peters:
Mr. Nyquist was not violated. Doug combined two statements. I built a system that transmitted 3 bytes at 9600 Baud, that is two channels with a reference byte. With that configuration I was able to run at a 200 to 300 Hz rate. The other version transmits 5 bytes, or 4 channels. On that version I set the sampling rate so that I see about 65 to 70 Hz. That avoids the 60 Hz causing aliases.
Juergen P. (Jim) Meissner
Check out my Website at www.MeissnerResearch.com
Read about the benefits of the Brain State Synchronizer sounds for improving your life and health.
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:32 BST