hai, everyone,

I need a small metal detector that can detect a small toy car... around 3cm x 3cm... the detector's coil need to be very small, around few cm, is it possible?

I have do a research on internet, all the circuit found was too big...

my project was just need a simple metal detector that will produce a signal when a metal object pass by...

is it must use a coil for metal detector? got any other alternative way?

 

Hello,

Can you mount a magnet under the car?
If so then you might be able to use hall sensors.
On this page you will find links with information on hall sensors:
http://www.educypedia.be/electronics/sensorshall.htm

If that is not possible, you could look for a capacitive proximation sensor.
On this page you will find links with information on those sensors:
http://www.educypedia.be/electronics/sensorscap.htm

Bertus

 

http://www.micro-examples.com/public/microex-navig/doc/076-picodetector.html

this metal detector was small enough, but it need to use PIC programming...