A simple arduino-based sensor that detects electrical currents (electromagnetic inteference).
- 1x Arduino Microcontroller
- 1x Mini Breadboard
- 1x 10-20cm cable lead
- 1x Green LED
- 1x Yellow LED
- 2x Red LEDs
/*
* Arduino EMI Sensor
* By Steven de Salas
*
* A simple sensor that detects electromagnetic inteference.
* It works because Arduino analog pins are very sensitive when using
* a 'floating ground' (ie when antenna is not connected to main ground).
*
* DIAGRAM:
*
* (Antenna)
* Y
* | +--------+
* | |* *|9 --O-| (Red LED)
* | |* *|8 --O-| (Red LED)
* | |* *|7 --O-| (Yellow LED)
* |- A3|* *|6 --O-| (Green LED)
* |* *| |
* |* *|GND --|
* +--------+
*/
int leds[] = { 6, 7, 8, 9 };
int thresholds[] = { 256, 512, 768, 950 };
void setup() {
for (byte i = 0; i < 4; i++) {
pinMode(leds[i], OUTPUT);
}
pinMode(A3, INPUT);
}
void loop() {
int emi = analogRead(A3);
for (byte i = 0; i < 4; i++) {
digitalWrite(leds[i], emi > thresholds[i] ? 1 : 0);
}
delay(10);
}