Can anybody please explain this pulse induction metal detector.plz

 

There seem to be some schematic errors around Q3. Even if you get those corrected, I don't think it's a pulse induction circuit. I think it's a Colpitts oscillator.
The coil inductance is also wrong. 500kH? 500uH, maybe.
Where did you get this schematic?

 

Respected Sir!

Thanks for your reply.

The inductance is put wrongly (Actually it is 45turns, 22 gauge and 3" diameter). I got this schematic from one of my friend, he also does not know anything

Please let me know what does these op-amp (741) do, and whats the logic behind this metal detector.
Thanks alot.

 

Here is a list of metal detector circuits, many of these are PI. All circuits has the same architecture.
http://www.next.gr/sens-detectors/metal-detector-circuits/