[Need help for a heartbeat detector!]

Hey bird... Did ya build the exact same circuit???

[Need help for a heartbeat detector!]

PIC?? ???

[Need help for a heartbeat detector!]

Hey Guru... Didn't quite get your point abt the output not going to zero... ??? BTW could u explain the PIC part of the circuit.. I'm totally new to the subject...

[Need help for a heartbeat detector!]

Hey Bird... Check out the data sheets for LM 358... Btw can't I like use two 741's instead? The specs are pretty much the same...

LM358.pdf

[Need help for a heartbeat detector!]

Hey Trigger...
The optical technique presented here exploits the fact that tiny subcutaneous blood vessels (capillaries) in any patch of skin (fingertip, ear lobe, etc.) furnished with a good blood supply, alternately expand and contract in time with the heartbeat. An ordinary infrared LED/phototransistor pair can sense this rhythmic change as small but detectable variations in skin contrast. That's pretty much the gist of the theory it's based on...

[Need help for a heartbeat detector!]

Are you working on the same thing?

DesignGuide.zip

[Need help for a heartbeat detector!]

Muah!!! :D

[Need help for a heartbeat detector!]

:-[Hmmm... Now I want to amplify it (a lot)... feed the output to a comparator and then to a mono to get like proper pulses and then count them (per min)... Any more suggestions... ???

[Need help for a heartbeat detector!]

Hey... Thanx for the help but I already got my hands on that one... :P But I've to work without microcontrollers and Pic... :-\ Don't know...

[Need help for a heartbeat detector!]

Hey... I'm working on a heartbeat detector & monitor (using photodiode & detector not microcontroller) for my mini project and need help in designin it... Any kind of help will be greatly appreciated...

Thanx