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Comment by pragone | Hacker News Reader

An EKG electrode needs to be Ag/AgCl to be reliable. Making your own is a good start to poor results.

I find this comment extremely unhelpful. Where would she be likely to find silver or silver chloride in her house right now in a convenient way to be able to make the electrode? The only silver I have in my house is a spoon my grandmother gave me (I don't get old people's fascination with spoons), so personally I wouldn't be inclined to monkey around with it, if I could get good enough results out of something else. And I assume she wants to use something lying around in the house because if she were to have to order something she might as well just order real electrodes.

Your comment comes off as "this other way that you are not doing is the best way, so you way may as well not even try". This is Hacker News, after all. A hack is, by definition, slapped together from what's available on hand.

Silver can be chlorided quite easily by immersing it in bleach for a short while (10 sec to a few min). The color should change, from the bright silver you know and love to a dull, darker gray. You can buy Ag wire for this purpose, or, I imagine, creatively salvage some from another source.

Yep, this is the "easy" way to chloride silver wires in the lab. I've chlorided silver wires by immersing part of the wire in bleach (regular household Clorox) and taping it in place so it sits for ~10-20 minutes.

Silver wire is pretty cheap online, so it's not too hard to get started.

EKG electrodes seem to be readily available, and cheap, too, in the US. IIRC, even the hypo-allergenic ones I had to get one time were not particularly expensive. I don't know if the rules are different in Finland.

http://www.amazon.com/Kendall-Covidien-200Series-Electrode-F...

In what way are the results degraded by a different choice of ions?

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