Earth Bondhon
Creators
Rojony Khatun Author
Rojony Khatun
CalculatorToolsProjectExpert
Reviewers
MaΕ‚gorzata Koperska, MD Steven Wooding
Last updated: September 23, 2025

Simple and Stable Metal Detector Circuit for DIY Projects

πŸ‡ΊπŸ‡Έ
English
Default
πŸ‡ͺπŸ‡Έ
EspaΓ±ol
Spanish
πŸ‡«πŸ‡·
FranΓ§ais
French
πŸ‡©πŸ‡ͺ
Deutsch
German
9012 Transistor

9012 Transistor

9012 is a PNP general-purpose transistor used in low-power switching and amplifier applications, commonly found in audio, signal, and small electronic circuits.

9018 Transistor

9018 Transistor

9018 is an NPN high-frequency transistor commonly used in RF circuits, low-noise amplifiers, and signal processing applications.

1K Fixed Resistor

1K Variable Resistor

Adjustable resistor with 1,000 ohm resistance

200K Fixed Resistor 1/4W

200K Fixed Resistor 1/4W

A 200,000-ohm resistor rated for 0.25 watts

1K Fixed Resistor 1/4W

1K Fixed Resistor 1/4W

A 1,000-ohm resistor rated for 0.25 watts

470 ohm Fixed Resistor 1/4W

470 ohm Fixed Resistor 1/4W

A 470-ohm resistor rated for 0.25 watts

3V LED 5mm

3V LED 5mm

3V, 5mm round light-emitting diode

100Β΅F Capacitor

100Β΅F Capacitor

Medium-value film or ceramic capacitor for AC/DC circuits

3V Buzzer Kit

3V Buzzer Kit

A low-voltage sound-producing module that operates on 3V DC supply. It is commonly used in DIY electronics, alarms, toys & indicators.

104PF Capacitor

104PF Capacitor

Medium-value film or ceramic capacitor for AC/DC circuits

Inductor 1mH

Inductor 1mH

A fixed inductor with 1 millihenry (mH) inductance, used in power supply filters, signal processing, tuning circuits, and energy storage applications.

[inductor-1mh]

*Please note: These are affiliate links. I may make a commission if you buy the components through these links. I would appreciate your support in this way!

simple and stable metal Detector

Build a simple and stable metal detector for hobby electronics. Detect metals easily using a compact, low-voltage, and beginner-friendly circuit with an LED or buzzer output.

simple metal detection project

A simple and stable metal detector detects nearby metal objects by sensing changes in inductance with a search coil. The circuit triggers an LED or buzzer for instant indication.

hobby electronics metal finder

The Simple and Stable Metal Detector is an easy-to-build project for hobbyists and electronics beginners. It uses a search coil and oscillator circuit to detect metal objects nearby. When metal is present, the circuit senses changes in inductance and triggers an output device like an LED or buzzer. This project is ideal for educational purposes, DIY electronics, and hobbyists who want a practical application of coils, oscillators, and simple signal detection. It operates on low-voltage DC, making it safe for breadboard assembly or small PCB setups. The detector is stable and can detect various metals, including iron, aluminum, and copper. Adjusting component values can fine-tune sensitivity and detection range. This simple design emphasizes ease of construction, stable performance, and low cost, providing a fun and practical electronics learning experience.

Work / Installation (Inputs β†’ Outputs)

  • Power Supply β†’ 5–12V DC low-voltage supply.
  • Oscillator Circuit β†’ Generates a frequency signal through the search coil.
  • Search Coil β†’ Detects metal objects by changing inductance.
  • Detection Circuit β†’ Compares signals, detects metal presence.
  • Output Device β†’ LED or buzzer indicates metal detection.
  • Installation β†’ Connect coil, oscillator, detection circuit, and output device; power ON; test detection by placing metal objects near coil.

Testing & Final Adjustments

Power the circuit and move metal objects near the search coil. The LED or buzzer should activate immediately. Adjust the coil position, sensitivity potentiometer, or component values to fine-tune detection range and stability. Verify the detection of different metals like iron, aluminum, and copper. Ensure the circuit is free from external interference for stable operation. Mount components securely on PCB or in a case for long-term use. Test multiple objects and distances to confirm consistent performance. Proper testing ensures reliable detection, making this metal detector suitable for hobby projects, small treasure hunts, and educational electronics experiments.

Frequently Asked Questions - simple and stable metal Detector:

What is a metal detector?

A device that senses the presence of nearby metallic objects.

Voltage required?

5–12V DC low-voltage supply.

Output types?

LED, buzzer, or both for indication.

Can it detect all metals?

Yes, commonly detects iron, aluminum, copper, and similar metals.

Is it beginner-friendly?

Yes, simple circuit with low-voltage operation.

Applications?

Hobby projects, educational experiments, treasure hunting.

How to adjust sensitivity?

Adjust potentiometer or coil parameters.

Can it run continuously?

Yes, but ensure proper component ratings and cooling.

Do I need a PCB?

Optional, breadboard works for prototypes.

Coil type?

Search coil wound with insulated copper wire for detection.

Rojony Khatun

Rojony Khatun

CalculatorToolsProject

Rojony Khatun is the creator of a free online tools website designed to simplify everyday and engineering-related calculations for students, professionals, and hobbyists. The platform offers a wide variety of basic and advanced calculators across key categories, including Electrical Calculators, Electronic Calculators, and Time & Date Calculators, helping users solve problems quickly and accurately.