Homemade EEG & EKG (ECG) Schematics
(last updated 7-Jan 2005)
DESCRIPTION
I developed my 4-channel, dual-purpose EEG/ECG box between September 2003 and March or April of 2004 with the gracious help of David Rosenboom at Calarts for use in my Medi[t]ations sound performance series. We combined schematics from his book Biofeedback and the Arts (available thru Frog Peak Press) with schematics from the article "Computers On The Brain" by Steve Ciarcia (in the June 1998 issue of BYTE magazine). We are also indebted to Ronald Kuivila who was instrumental in unlocking the mystery of how to get the low-frequency audio signal into my computer and subsequently into SuperCollider...
DISCLAIMERS
WARNING: USE AT YOUR OWN RISK. If you download the following schematics and attempt to build this device, you must assume all responsibility for any misuse, injury or death that may ensue. This device is neither guaranteed to work nor certified to be safe. A general suggestion is to never ever power this device with AC (i.e. from the wall), only with DC (batteries). In addition, do not connect this device to anything that is connected to AC power.
Consider yourself warned.
This work is licensed under a Creative Commons License.
The schematic may be freely used, shared, and modified, however it may not be used for commercial purposes. Please credit the authors where credit is due.
SCHEMATICS & RESOURCES
Okay, here are the schematics: pdf | postscript file | parts list (coming soon)
And here are some potentially helpful links to cheap electrodes, electronics parts, resources, etc
I have successfully used this device with model TD-429H Reusable EEG Electrodes from DiscountDisposables.com, but check around: there seem to be a handful of companies out there with cheap deals. Every once in awhile it seems like one of the electrodes dies, but you can get a whole bunch for pretty cheap, so maybe it averages out alright over time. AND: it must be noted that on my device, I used typical female pin jacks, however the electrodes mentioned above come with some weird and incompatible pin leads; PLUS, the company sells some very expensive adaptors that were supposed to fit my standard jacks, but didn't. Instead, after getting the electrodes, I ordered some standard pin leads for super cheap, and replaced the funky ones with the standard ones. It seemed to work fine.
Also, instead of using the standard electrode collars which seem to be incredibly hard to keep attached to the body, I have actually found it much easier to just use clear bandaging tape that you can get in the first aid section of any pharmacy.
PICS
Here's what my baby looks like...
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and here's what my SuperCollider interface looks like
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