-a 9 volt battery
-9 volt battery connector
-a LED (any color)
- a resistor 100 ohm -/+5% color bands are: brown, black, brown (needed for the 1.5v LED)
-and of course a metal sensor. I got mine from SunX.com, but you can try a number of different robot part sites or electronic components suppliers. try and get one with a LED built in that way you can see if the metal detector works when it touches metal.
OK lets get started!
Also don't forget to visit the site!
Step 1: The circuit
Step 2: Test
the LED is simply to let you know there is power going to the metal detector.
A video of the metal detector in action