View Full Version : CardioMeter : A remake.

04-24-2010, 06:58 PM
Hello All,

I had been thinking of making a heartbeat frequency counter(heart rate monitor) which is mostly seen in Gym treadmills. I made one with optoelectronics using high power led. The concept there was to measure the difference in light intensity due to change in blood pressure in the test finger.
Now, this time I want to be more precise and aesthetic as well. Some electrical heart rate monitors that I've known use one electrode on each hand and and one on a leg ( for reference voltage ). But the one in the Gyms uses only two electrodes. I havent done a indepth study of heatbeat pulses,so dont have much idea about what to look for.
If anyone out there knows what exactly goes inside those gym devices ( and similar ones) then please help me out.

PS: I am not asking for the circuits and all... All want to know how those devices work, rest I can design by myself.


04-24-2010, 07:36 PM
You want to make it portable or connection with PC will do ?
In latter just look for DIY ECG

04-24-2010, 08:54 PM
The Device is supposed to be portable and small with 2 probes at most!
And thanks for the Link , that'll be a lot o help!

Q: Cant the PC used in above link be replaced by a uC (AVR) ?

04-25-2010, 01:08 AM
Then please look into this


04-25-2010, 01:25 AM
Thankx again for the link... Thats a fully developed project!
I was thinking of putting in my own brain... but yeah the links will surely give me new ideas.
Will get back to you about my new project's progress.

And everybody else out there, 'New ideas and comments are invited'.

04-25-2010, 12:10 PM
HI Mgear,
You have to many if and else conditions like two probes only ...ideas only ...no complete project.........anyways try looking at the website of major chip manufacture for exapmle check this out : http://focus.ti.com/docs/solution/folders/print/464.html
One must search using google we always stress this.


04-25-2010, 08:39 PM
@asimov : Great find , Ill be having fun with OCZ Nia soon and if it works out i might order the Ti chip ... Maybe devlop a lower cost Emotive headset :) ... Having fun with brain computer interface ... lazy me dosent want to lift a finger ;) .

http://www.open-ecg-project.org is another great resource ...

04-26-2010, 11:45 AM
@ vikas : at how much USD you are getting OCZ Nia.

04-27-2010, 01:04 PM
Amazon OCZ Nia was 109 USD.