Report Electronic Stethoscope in Projects Q/A Posted November 10, 2003 :)Thank you very much to all who replied to this forum. Though I am very slow to complete this apparently simple project, I still failed to make it work. I have tried achaila's method of inverting the polarity of the MIC (I do not know what model it is... it is a tiny one around 5mm in diameter), but still it doesn't work well.One thing I can say is that I have fixed all the components correctly. The only thing I replaced is the Bi-polar LED with a normal LED. and i dont think it will affect the circuit considerably.Maybe it's the way I construct the circuit.... maybe it's wrong... but I couldn't find any mistakes... :-\ thanx a lot!Anyway, I really appreciated all the help and advice. :D I've learnt many valuable things in the process.and also I will be constructing many other circuits in this website!