This is the heart rate meter simulation figure, could you tell me how to analog input pulse signal, the oscilloscope in which position can see after amplification and compare waveform figure

CodePudding user response:

Function generator has three kinds of waveform is available, the adjustable output amplitude frequency, etc.,

CodePudding user response:

Heart rate sensor is generally use the LED light (red) light skin after measuring the reflected light or transmission light penetrate the skin, the blood in the capillaries of the skin changes with the heartbeat, the reflected light or transmission light will change as the heart, heart rate is low between 0.3-3 hz, behind the sensors usually need to put a low pass filter amplifier circuit, look at your circuit C1, C3 on the right side is low pass filter amplifier, on the left side of the part should be the sensor input, D2 should be LED light, should be a photosensitive diode D1, type is pervious to light or reflective couldn't judge on the graph, the oscilloscope should be put on P3.2, in Q1 base with 1 hz, triangle wave, sine wave, square wave, millivolt level simulation signal, should be in P3.2 output pulse pulse,

CodePudding user response:

This principle: infrared heart rate sensor is sent by infrared diodes, infrared receiving diode and related circuit composition, when peripheral vascular infrared beam through the human body, because the pulses with blood volume changes in the light of the light transmittance change, when received by photoelectric converter body tissue reflected light, converted into corresponding electrical signals, and by the Lm324 operational amplifier through secondary amplification and voltage comparator input to the single chip microcomputer for processing, if want to test, can put in mouth of P3.2 oscilloscope, but it will take between send infrared diode simulation, otherwise the oscilloscope shows the initial signal, the principle of the above qq_708907433 right,