Introduction: Rudimentary EMF Detector

This is a project that requires little experience with electronics and arduinos. The device featured is a simple EMF detector that picks up stray charges from its surroundings. If the antenna protruding from the arduino is within range of a wire or some other electronic device the red led will light up. The equipment required for this project is a arduino, a 100k ohm resistor, wires, a breadboard, and a led. The inspiration for this project came from the EMF Detector made at

Step 1: Collect the Materials Needed

  1. Arduino
  2. 100k Ohm Resistor
  3. Wires
  4. Breadboard
  5. Led

These parts would be simple enough to find anywhere electronic components are sold. This project is intended to be accessible to those with no experience with electronics. If you are unfamiliar with breadboards refer to this link:

Step 2: Code

The c++ code below is what I used in order to make the led sensitive enough to the change in charges reaching the antenna.

int inPin = 5;

int var = 0; int pin11 = 11;

void setup(){



void loop(){

var = analogRead(inPin);

if(var >= 1){

var = map(var, -1000, 100, 1, 255);

analogWrite(pin11, var);


analogWrite(pin11, 0);




Step 3: Assembly