Small Metal detector schematic circuit

Posted on Mar 27, 2013

This metal detector circuit needs to be powered using a 9 volts power supply ( DC) or a 9 volts battery . The C1 capacitor is a variable capacitor with a value of 365 pF , C2 is a 100pF silver mica capacitor , C3 is a 0.05 uF disc capacitor and the C4 is a 4.7 uF capacitor . The Q1 transistor can be RCA SK3011 npn transistor or equivalent type and all resistors need to be ½ watts .

Small Metal detector schematic circuit - image 1
Click here to download the full size of the above Image.

This metal detector schematic circuit is based on a transistor radio as an detector . With the radio tuned to a weak station you must adjust the variable capacitor C1 until the locator oscillator beats against the received signal . If a metal is detected the inductance of the L1 coil is changed , changing the frequency of the locator oscillators , resulting a change in the beat tone radio . The L1 search coil of the metal detector circuit must have 18 turns from a 0.65 mm enameled wire scrambled on a 4 inch diameter support .

Leave Comment

characters left:

New Circuits



Popular Circuits

ATmega8535 Line Follower Robot circuit diagram
op amp Why do some of my IE converter circuits have a large offset voltage
three digit display.
ldr engineer
Simple battery charger circuit and battery level indicator with low battery recharge alarm
Current amplification for driving stepper motor
220V Power Line Interface
Simple Transistor Amplifier Circuit Schematic and Explanation
Flyback Transformer Driver
Bar graph LED
Simple Two-Transistor Motorcycle Alarm