cs209A metal detector circuit

Metal Detector DIY Circuit

The heart of this diy metal detector circuit is the CS209A IC. The metal detector is built with one 100µH coil that has 40 mm in diameter and is made of 50 turns/0.4 mm wire. CS209A has one oscillator wich forms a LC circuit, the inductance of the coil will change when it is near metal objects.

LED 1 will light up and the buzzer turns ON when the coil is changing inductance. The setup is easy, VR1 is adjusted (away from any metal objects) so that LED 1 will light and the buzzer sounds on, and then VR1 will be trimmed until led and buzzer are off.

DIY Metal Detector Circuit Schematic

cs209A metal detector circuit

cs209 metal detector on breadboard

This is the updated and working circuit. The old one can be seen here and has a lot of errors. This is why not every circuit available on the WWW is trustworthy.


Join the conversation!

Error! Please fill all fields.
  • Jose Calderon

    What needs to be change in the original diagram in order to reach a detection of 36 inches depth?

  • valdas

    Dekoju uz schema surinkau veikia. Tik rite as panaudojau suviniota ant serdies. Radau kazkokiam maitinimo bloke.

  • Himanshu Garg

    we want to make a pulse induction metal detector for our major project but we couldn’t fine any tested circuit or working circuit.. we are 5 in group so budget dosent matter. plz help us to make a working metal detector circuit…

  • kaycee

    Please i do not understand the aspect of 100uH.. what does it mean?

  • ellmer

    What is the IC number for the heart of the circuit mentioned?

  • neshamil

    Hi everyone , especially the ” electrolover ” . Sorry , I’m late for several years about this ” metal detector ” but it does not matter , I might give you some good advice .
    I made ​​a simple model with only one transistor (BC 548b ) and it works fine at a distance about 10cm of pure metal (such as small pliers, a small screwdriver , tin solder and small coin – yellow or bright colors). I tried an experiment with a silver bracelet and I’m surprised positively – conditioning was revealed at a distance of 5 to 7 cm from the coil to the parquet floor in my room . I’ll try the same with gold objects soon .
    I watched your video ” evectrolover ” and maybe those other brothers say where you’re wrong , but I will tell everyone what I think is very important for the metal detector ( for further MD ) , especially for the youth of electronics ( like my son who will stubbornly to hear ) .
    So it is very important that the search coil (L1 ) is designed as well as a complete spool to physically isolated material.

    So to close not even a single screw or wire lines L1 adherence to the road up to the plate with parts in the unit. I dismissed my coil L1 at about 1.5m of an electronic plate on a wooden dowel about 1.7m. and all fixed with plastic guide, adhesives, insulation tape and rope and plastic …
    Your coil L1 is on the plate with elekrto-semiconductors, but the panel has a metal jumpers inside. It is not right solution for L1.
    Second, it is always better to be wound L1 which spread in a circle or square shape. Mine is about 15cm square, a better, even more so about 25cm I think.

    OK, I hear it still, greetings for “elektomaniaks”

    • abbas ali shah

      i need an accurate and complete circuit diagram of a metal detector and i m using it in a robot kindly give me idea to increase range and efficient metal detection
      waiting for ur reply …….

  • nini pelet

    is not complete , caps 10u &100u ,how many Volt? because many kind with the same number in micro par or other.. please more detail, that will easy me 4 try you experiment. thanks you

  • suthat

    This is a metal detector in a few cm.

  • ทัด

    วงจรตัวนี้ตรวจจับโลหะได้ระยะกี่ cm ขอบคุณที่ตอบนะ

  • emac

    does it work??

Looking for the latest from TI?