A simple metal detector works with the principle of electromagnetic induction. The metal detector consist of different types of parts, the main part is the induction coil. The symbol metal detector consist of an oscillator. Second one is the coil and the third one is the detection mechanism circuit. So in this article, I would like to share the metal detector circuit using TDA0161 IC.
Basic Working Principle of Metal Detector
when the electronic circuit is powered on the oscillator will generate the oscillating current through the searching coil (searching coil is known as the induction coil). The oscillation frequency is depending on the circuit parameters.
when any metal objects come near to the induction coil, it changes the inductions of the inductor which will change the frequency of the oscillation. The oscillation is suddenly changed. It will detected by the internal circuit and it will glow the light or sound of detection.
In this article, the provided Circuit is very simplest form of metal detector circuit. It cannot able to detect the large metal object, for more sensitive and specificity the more complex circuit you will need.
Simple Metal detector circuit using TDA0161
The circuit diagram consist of fuel number of external components. The main component is TD 0161 IC, which is the heart of the circuit. When metallic object comes closer with the inductor, which will changing the inductance and the frequency of the coil. The change of frequency and the current in the detector is depending on the metallic object what we are found. If any kind of metallic object is found the LED diode turns on.
You can also use this LED connection circuit direct directed to the bus circuit to hear the sound when any metallic object was found by the detector.
Metal Detector LC Circuit
The metal detector using the LC circuit based on the principle of resonance. When metal object comes to close with the coil, it changes the inductance which alter the frequency. When any changes in the inductance value will be noticed by the internal circuit.
