Hello,
I have a school project and I need to construct electronic stethoscope. I could choose some designed circuit and build a stethoscope according to this scheme. I chose electronic circuit which I found on this forum. I know all values of resistors, capacitors and stuff. But I would like to ask you, if you could give me some information about the type of microphone that I can use and about parameters of this mic.

 

hi,
I would say its a 'electret' microphone.
https://www.google.com/search?q=ele...oTCPH_5MflrcgCFQU_FAodcGkPPg&biw=1437&bih=925
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Thank you very much

 

And don't you know what type of electret microphone i should choose? And I have a question: What is the function of C1and C6? Do they smooth signal? My teacher thinks that we can eliminate them but don't I need anything to achieve as much "clear" signal as it is possible?

 

hi,
The function of C1 is to decouple the power rail to the electret, I would recommend that you do not remove.
C6 is part of the power rail decoupling, I would not remove it.

I would have thought for a medical instrument that the reduction of any stray electrical noise would be important.

Why does your teacher think you should remove them.??

I would choose a electret microphone that has a flat frequency response over the range of frequencies you are measuring.