I'm working on a project to use doppler effect to hear baby's heart voice (when is not born!!!).
so I need a osccilator about 2.16 MHz and reciever may be an AM demodulator or etc.
any1 could help me.......
Interesting project, I do not know what info you are after. I have some papers about the ultrasound and sensors, but I think the hardest part will be the signalprocessing to distinguish the babys heartbeat from the mothers. Tell us more, is it hardware or software problem then it is easier to help.
One of these systems takes many experienced engineers several years to design and get working. It is unlikely that one individual without prior experience will be able to make one.