Search results

  1. D

    Electronic Stethoscope

    I was also wondering if you might be able to post a picture of the mic and it's holder.  Where is the rubber grommet placed?  The noise I hear is a small intermittant bursts of static.  It's difficult for me to tell whether I'm hearing a heart beat or whether all I'm hearing is noise.  Is the...
  2. D

    Electronic Stethoscope

    I did build project 2 and I didn't substitute any parts.  Do you know what the specifications are for your microphone?
  3. D

    Electronic Stethoscope

    Hi again,   I was just curious what the sensitivity and signal to noise ratio of your microphone was.  I have the circuit built, but I'm having a hard time distinguising between possible heart beats and random noise.  Is there anything I might do to help with this?  I was also wondering if the...
  4. D

    Electronic Stethoscope

    Hi again,   I was just curious what kind of voltages are output from the microphone from a heart beat.  I ask because I haven't bought a microphone yet and I just wanted to input a sine wave to make sure the circuit works.  I'd like to know what voltage to input into the circuit.  Thanks for any...
  5. D

    Electronic Stethoscope

    Thanks a lot for a quick response!! Since I have to build this circuit for a class and justify why each component is a certain value, I was wondering if there is a certain reason for the gains in the circuit (for example, why does U1a have a gain of 3.9 and U1b have a gain of 1.6?)  Thanks again!
  6. D

    Electronic Stethoscope

    Dear all,   I am just starting to work on this project for a design course.  I was trying to understand the uses of each of the components in the circuit diagram.  What are the uses of R1, C1, and R16?  Do they create a voltage divider?  If so, what is the output voltage supplied to the mic? ...
Top