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Specifically, I want to know if the KY-022 module and KY-005 module can be used for heart beat detecting according to this tutorial?

KY-005:

enter image description here

KY-022:

enter image description here

If so, can you please explain to me how can I achieve such thing with respect to the following:
1- Is there any kind of synchronization between transmitter/receiver?
2- How to get a stable analog value from the receiver?
3- The Correlation between Heart beat rate and the obtained values?

providing circuit sketch will be very helpful but not necessary.
Thanks in advance.

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    1. If you watch the video and try to work out what you are seeing it should be clear. [No - the transmitter is simply an IR light source.] 2. No need for stability - look for local maxima and minima at frequencies that are "about right". An FFT of the signal may be useful but is overkill. 3. Did you watch the video? If so, watch it again. Look at the waveform on the oscilloscope. You are, of course, seeing the heart beat. – Russell McMahon Mar 20 '15 at 7:13
  • Tutorial link broken. – Dave X Feb 28 '16 at 17:47
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No, you cannot. The sensor you link to has a circuit which attempts to detect IR light modulated at a specific frequency, and produces a digital output. For a heartbeat sensor you need an analog output to feed into far more sophisticated signal processing - effectively the built-in processing gets in the way and means you cannot use it for this purpose.

Additionally, sensors of this type typically have an automatic gain control which means that they desensitize when subjected to continuous signal - they are designed for sources like remote controls where the modulation is itself pulsed on an off in small fractions of a second, so they interpret constant modulated light as noise and soon turn off their output.

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