hi
Extract OP:
brief of the project
design,construct and test a circuit consisting stethoscope probe,o/p signal conditionin circuit with an audio indication if the reference value is exceeded.Circuit should be mains operated.
If this was your initial project spec, where did the stethoscope idea come and why is now not used???
What circuitry, what transducers ??
Why is the mains part so important?
I'm sure there are lots of guys/gals happy to help you, but tell us what you trying to do and don't keep changing the spec.
Eric