# How to Make a Cheap and Simple Metal Detector

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I'm a big fan of pirates. You know how they hunt for treasure. But hunting for treasure isn't always easy. BUT I have a thing that might help you. The SIMPLEST and CHEAPEST metal detector.

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## Step 1: 555 Ic

You should first know a little about the 555 ic. There are totaly 8 pins in it. The pinout is given in this step.

## Step 2: Collecting the Things

This metal detector is very simple and is based upon a very famous and easily available ic which is 555 ic. The things that you will need to make this metal detector are

555 ic
47k resistor
2.2 uf capacitor- 2
10 uf capacitor
8 ohm speaker
6 to 12v dc power supply
10 mh (milli henry) inductor/choke

## Step 3: Making the Metal Detector

Assemble the circuit on a perfboard or pcb except the inductor. Attach two long wires at the place of the inductor. Use a long rod and place the inductor at the end. If you are still confused about the installing of the inductor and the circuit just see the picture. The schematic is given in this step.

## Step 4: How It Works?

If there is any treasure underneath your house or your garden or anywhere, now you can find it.This metal detector can detect metal as well as magnets. When a piece of metal or magnet is brought close to the inductor/choke the output frequency changes and you can hear sound from the speaker. The schematic and info were taken from talkingelectronics.com

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## 31 Discussions

It depends on the inductor. If you use a 10 mh inductor it will detect upto 1 to 2 metre deep.

can we increase the inductance from 10mH and do we must to change the capacitor ?

what is also the frequency of operation of this circuit

If all of the components values are nearly accurate, the frequency will be about 93 kHz.

why metal detector was contuie buzzing

any one have a video of this project lpz mail me at zulfiqarbajeer3@gmail.com

i want to make a metal detector using tda0161, when the detector detects the metal from a specific distance the buzzer sounds but as the metal comes near and near the buzzer sound increases!!

so anyone guide me for this

i m using this with arduino

I doubt it. I think the point is that the inductance is supposed to change as the coil comes closer to the metal, kind or acting like a ferrite core you might find in a pcb inductor.

Hello....What is the frequency range for this circuit??? And can you tell me why is the pin number 5 and 7 left as it is???

I HAVE MADE THE CIRCUIT BUT I CONFUSED FOR 10mH INDUCTOR CAN YOU HAVE THE VIDEO OF MAKING IT FROM 555 IC FOR MY BETTER EXPLAINATION AND YOU HAVE PHOTOS OF IT HELP ME PLEASE ^_^

For every one having trouble with building it, I made this metal detector and you can find it here.

I hav a problem while building it, can anyone tell me where is the pic number 6 and 8 in this circuit diagram of metal detector?? Which is pin 0 in IC 555..?