|
|
Building an EEG at home with the OpenEEG project
Acquiring the parts |
||
| Previous: Preparation | Contents | Next: Building the circuits |
The total cost of the parts was $195 (NZ$380).
This section discusses where I got my parts from and what it cost. All prices are in US dollars unless stated and all shipping was to New Zealand.
My purchase orders (covering BOM listed items only) can be viewed here: orders.txt.
I have summarised everything into following categories:
My circuit boards were printed by Olimex, a Bulgarian circuit board manufacturer.
The boards (OpenEEG version 0.04) can be re-ordered by using this order form: sg300902.PDF. If you wish to order a later version then you will have to obtain a template reference number for it (ask the mailing list) or pay extra for an initial cut.
To order:
Send an email with your name, address, shipping option (ie. airmail parcel) and quote the reference number of the board that you want. Olimex will send back an order form. Payments can be made by credit card.
Cost: $32.45
Estimated time of delivery: 2 weeks
A list of the required electrical components and the associated reference information is summarised in the bill of materials (BOM) located in the modularEEG files (see plans).
I ordered from four vendors:
This site is in German so use Babelfish to translate.
The 47uF capacitors from here have an ESR of 2 ohms.
To order:
I used the online order form and my credit card to make the purchase. This was unnerving because I do not speak German, but it was worth it because most of the parts are here and the ordering codes are quoted in the BOM.
Cost: $90.00
Estimated time of delivery: 2 weeks
I could not find a TMV0505S dc-dc converter so I ordered an NMV0505SA from here instead. There is a footnote warning in the BOM that you need to read when using this part. Despite the warning I read 5.6V on IC103 pin 8 and did not have to take any extra measures.
Cost: $24.65
Estimated time of delivery: 2 days
The 47uF capacitors from here have an ESR of 2 ohms.
Cost: $16.97
Estimated time of delivery: 2 days
This is where I found the elusive 0.8 ohms ESR 47uF capacitor. I also added a rocker switch to the list because a minimum order of NZ$10.00 was imposed.
Cost: $8.00
Estimated time of delivery: 1 weeks
Not included in the BOM.
I just happened to have an old 9V 200mA DC power supply lying around which was ideal. I purchased a dc power plug and socket for it and added a rocker switch to turn the eeg on and off (covered in my order from farnell).
Cost: $2.70
Estimated time of delivery: purchased in person at Dick Smith
Not included in the BOM.
These are the cables you will need:
I already had these parts, except for the following which I ordered from Dick Smith:
Cost: $4.50
Estimated time of delivery: purchased in person at Dick Smith
Finding an adequate box was a difficult task. The best I could find was a rather pricey piece of plastic from Dick Smith: Small sloping case, cat H2193 NZ$17.20
For my shielding I used adhesive aluminium tape (already owned).
Cost: $8.00
Estimated time of delivery: purchased in person at Dick Smith
See DIY electrodes.
I also used a 5 pin din plug and socket which I already had.
Cost: $7.80
Estimated time of delivery: purchased in person at Dick Smith
| Previous: Preparation | Contents | Next: Building the circuits |