I stumbled upon this simple metal detector circuit. I wondered if it really had this function. After analysis, I found related videos to confirm that it was indeed possible, and then I made one by myself. Please be sure to check the relevant information before making it to figure out the principle of the metal detector. 1. Tools and materials Components: -555 -47kΩ resistor -Two 2μ2F capacitors -Circuit board -9 volt battery, switch, some wires -Buzzer -100 meters of copper wire with a diameter of 0.2 mm -Tape and glue You can use a 10μF capacitor and speaker (8 ohm impedance) for the buzzer. tool: -Breadboard and wires -Pliers, tweezers -Soldering iron and solder wire -Sharp knife, ruler, pencil, compass -Hot glue gun 2. Schematic This picture was found on the Internet. I just added a switch between the switch and the circuit, and replaced the speaker with a buzzer. 3. Coil The coil is the most difficult part. By calculation, a 90mm diameter coil requires about 250 windings, and a 70mm diameter requires 290 windings, and the inductance can reach 10 mH. You can also buy ready-made coils online. Calculator address The coil core is made of cardboard. The coil used is 0.2mm diameter enameled copper wire. I made 260 laps. Before soldering, please hang up the paint on the end of the wire. 4. Test After testing, it really works! (Not available in the video) 5.PCB After the test was successful, I made this PCB circuit 6. Cardboard structure In order to make the final work beautiful and easy to use, I made this cardboard structure. 7. Assembly All the parts are ready. The following is to assemble them all. First fix the switch with a glue gun, then put in the battery, and finally fix the circuit board with the glue gun. 8. Summary This metal detector is very, very simple. But its detection function is also limited. It does not work normally when used outdoors. However, for beginners, this is indeed a good work, I love it! Vecsel Module,Laser Module Violet,10 Watt Laser Module,Laser Module Fritzing AcePhotonics Co.,Ltd. , https://www.acephotonics.com
