In this Instructable learn ho to create a very simple, low cost metal detector. This is not the type of large scale metal detector you can use on the beach however,this can be used for finding where two studs in your walls meet ,locating the nails, a lost screw, screws, or just simply fooling around testing different objects around the house.
-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 ebay. 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.
The circuit is very simple. For assembly please follow the provided circuit diagram. Remember that the LED and metal Detector are polarity sensetive.Test each component before soldering them all together.
Flick the switch or hold it down, depending on what type you used. hold the detector to some metal and if the light inside lights up, its metal! The LED is simply to let you know there is power going to the metal detector.
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