From: Jim Meissner (jpmeissner_at_mindspring.com)
Date: 2002-02-20 17:38:05
Dear Andreas:
Hope you are making good progress with the PC boards. If I can help let meknow.
You make a good point about testing the filter response. The file log001.dat was done just for that purpose. It contains sinewave data sweeps through frequencies and that is steady, pulsed, AM sine wave modulated, FM modulated. If you look at it with my slink12r FFT waterfall display you will seeboth the sine wave signals and how the FFT interprets the answer. You will see a single frequency when modulated splits into the center frequency and two sidebands. The method of looking at the brain wave data affects whatmay or may not be there in reality. It is always good to put in a known and see what the program does with it.
I was very much opposed to Jim Peters idea of high Q filters knowing that it will created false data and artifacts such as the Mind Mirror filter problems. So far I am very impressed with what Jim has done with his bwview program.
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.
----- Original Message -----
From: sleeper75se
To: buildcheapeeg_at_yahoogroups.com
Sent: Wednesday, February 20, 2002 9:26 AM
Subject: [buildcheapeeg] Re: BWView
--- In buildcheapeeg_at_yahoogroups.com, Jim Peters <jim_at_uazu.net> wrote:
> I'm making some progress with my recorded brain-wave viewing app.
> Here's a screen-shot:
>
> http://uazu.net/temp/20010217.gif
Hi Jim,
Wow! :-)
I hope you can find a way to make it more real-time friendly.
By the way, a good way to determine how fast an IIR filter "forgets"
a signal is to input an impulse and see how long it takes for the
output to settle below some (arbitrary) threshold.
Regards,
Andreas
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This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:38 BST
