since you typically want better than just the Nyquist limit (sample rate/2), which causes lots of aliasing. So say 4 samples per waveform would limit you to 25 Hz maximum EEG. Not very appealing, but

Profeell, do a search on Nyquist Limit.

 fn = sampling_freq/2 # calculate the nyquist frequency 

first link. I remember the relationship between nyquist frequency and the highest frequency component of a signal, but just mixed up the variables. 

http://openbci.com/forum/index.php?p=/search&Search=nyquist

Oversampling produced no significant changes in timing and amplitude measures of the rectified or smoothed electromyographic signal. For the smoothed signal, minor undersampling at half the Nyquist ra

The Nyquist stuff is interesting. I suspect that I will need sample rates in the thousands, possibly ten of thousands, but don't know for sure yet. My line of thinking is that it is better to be safe

Also see the info about the Nyquist limit as relates to EEG,

https://www.google.com/search?q=sample+rate+nyquist

2. Google "nyquist limit". You need at least 2, preferably more samples per sample wave period. 250 Hz can at the most get you 125 hz waves, but better with 3, 4 etc samples. So 80 hz. Even

Resampling is sometimes done to reduce a high sample rate (such as 1000 or 500 hz) down to rate that requires less computational resources. As long as your final sample rate is above the Nyquist limit

So the Nyquist Frequency (NF) would be 125/2=62.5.

re: 'My thought is, if this is the board with 250Hz sample rate,  it should handle at most 125Hz waveforms (Nyquist limit)"

and harmonics, you need more than just the Nyquist limit. Probably more like 5, 6 or more samples per waveform cycle. 250/6 = 41.6 hz.

sample rate drops to 125 hz. Even at 250 hz, the Nyquist limit starts to come into effect at roughly half the sample rate. In other words there are not enough data points to approximate the smooth cu

The observation about sampling frequency is also true. All you get is a larger Nyquist frequency, hence you can capture higher frequencies content, but increasing the frequency doesn't improve your fr

Note that due to the Nyquist limit, the 250 hz sampling rate could at best only include 125 hz EEG. But even that is a stretch because there would only be two samples per cycle. Also, when you start g

Thanks Chip.<br />It looks as though I have some study to do. I may get back but will delve in myself for a while, Data collection speed is an issue as the Nyquist limit starts creeping (gallo