

Minimal ECG using an Arduino and Xoscillo - Jare
http://codinglab.blogspot.be/2013/07/my-heartbeat.html

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JshWright
That's an absolutely phenomenal trace... Obviously he's working under somewhat
idealized noise conditions (as he described), but that trace is _cleaner_ than
what we get out of the portable ECG monitors we carry in the back of
ambulances (it also has much higher resolution). These are monitors have a
price tag that you'd be more familiar with on a new car...

Don't get me wrong, I'm well aware that there's a big gap between some wires
in a breadboard and a ruggedized, battle tested 12-lead. I'm not complaining
about the cost of our Lifepacks; rather I'm ust blown away at how great that
trace looks with such rudimentary equipment.

I'm gonna have to 'borrow' some electrodes from the station and give this a
shot myself...

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xchip
Hi, I'm glad to hear that, I'll be happy to help if you plan to build one!

As for the idealized conditions, if I gently pass my finger on my laptop's
aluminum case I can feel the 50hz hum, so that is why I have to unplug it to
get that signal, it may be a laptop's issue. I will check with a desktop and
post my results.

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JshWright
Which lead was the picture from? That biphasic morphology of the T wave is a
little unusual. Do you have an older ECG to compare it to?

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xchip
Yes i noticed that too, I thought it could be because I put the leads where
ever I felt like.

I am using 3 electrodes, the reference one (ground), was on my right thigh,
the other two were, one where my right chest meets the shoulder and the other
one on my left side at the level where the floating ribs are...

I placed them in non standard positions so that is why i may be getting funny
values... But I agree that lower lobe is not in any ECG I have checked so
far... I may go to the doctor to double check..

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JshWright
That's close enough to the standard Lead II. A biphasic T wave in that lead is
technically abnormal, but there are a number of benign causes. Certainly
wouldn't hurt to check in with your doctor though (and you get to tell him a
cool story of how you discovered it)

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xchip
Hey! Thanks for letting me know! I'll try to get a real ECG as soon as I
can... I hope that negative lobe is just an artifact :) Thanks again, and if
you need help building one please let me know I'll be happy to help!

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jentulman
I'm good enough to follow along a diagram and build stuff I find online, but
have no real clue as to the electronics.

Given I have a neglected arduino kicking about and a paramedic I could
probably get some electrodes from how far removed is this kit from knocking up
a very basic 'brain controller'?

I've often fancied feeding some 'thoughts' into Ableton for some synth
tweaking fun.

[edit] thought I should actually do some searching on the subject and I just
found the openEEG project which has some info in that direction.

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xchip
Yeah, another thing to try is to connect it to my head to see what I get.. I'd
need to increase the gain a bit though

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dorfsmay
I am assuming you do the A/D conversion with the electronic board, and then
treat the digital signal with the Arduino?

How difficult would it be to wire your A/D conversion unit to do USB? Then any
laptop, or even a smart phone could do the UI part. Or am I missing something?

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xchip
The arduino has an ADC conversor and sends it with no posprocessing at all to
the PC. This could be easily used with a smart phone indeed, in fact that is
my next step :)

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cnvogel
There's prior art on that one... (using the microphone input as a ADC, sending
power to the preamp via the headphone output)

[http://web.eecs.umich.edu/~prabal/projects/hijack/](http://web.eecs.umich.edu/~prabal/projects/hijack/)

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kryten
Great work! This is why I come here :)

I built a pulse oximeter as my final year project at university and have been
rather obsessed with medical electronics since.

I've always wondered if it's possible to build your own ultrasound sensor.
Rather complicated devices though.

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DanBC
Is it still good practice to have opto-isolators on anything that you're
wiring up to your body?

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Hydraulix989
I would DEFINITELY use opto-isolators (my EEG BCI had them) and would always
run the ECG on a laptop with its AC adapter _unplugged_. Do you really want to
risk even a small chance of electrocution?

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dodo53
this would be a cool school science lab experiment

