How to make a simple detector of electromagnetic fields?

  • Dec 26, 2019

There are two types of currents, by which electromagnetic fields are created - direct current (DC) and alternating current (AC). The detector measures the electromagnetic field EMF generated alternating current. The main feature of this process is that the current is moving in two directions up to fifty times minute, whereas when the constant current is static and can not be measured by most detectors EMF.

What is an EMF detector?

EMF detector - a measuring device which is used in various industrial applications, to detect problems in intrahouse wiring and power lines. EMF meter provides information about the workflow in an electromagnetic field by measurement of electromagnetic radiation flux density (DC).

In addition, this device can track changes in the electromagnetic field that occur in the wires during operation for a certain period of time.

Measuring EMF detect problems in an electromagnetic field supplied with sensitive components which are part of the monitoring device. With its use, it is possible to prevent accidents on the network, thereby ensuring a safe environment in which people live.

EMF detector with their hands

In fact, the device is not complicated and can be done by yourself hobbyist.

This we need to work
This we need to work

For the electromagnetic field detector emf dual operational amplifier and 2 inductors require the following set of radio materials and tools:

  1. EMF-detector circuit board or cardboard can be used;
  2. 9V battery clip (6f22);
  3. 3.5 mm stereo audio jack;
  4. LM358 or any other dual operational amplifier is compatible with your contacts (TL072 works fine)
  5. radial inductor 2x - 100 mH may be denoted as 104 J;
  6. Light-emitting diode;
  7. potentiometer 500 ohms stereo line;
  8. N4148 diode or any other general purpose;
  9. resistor 3x - 1 k;
  10. resistor 2x - 10k;
  11. Resistor 100 ohms;
  12. 100 microfarad electrolytic capacitor, any nominal voltage;
  13. 2.2 microfarad electrolytic capacitor, any nominal voltage;
  14. a few meters of the connecting wire for connecting the potentiometer, audio jacks;
  15. housing;
  1. LED holder, 10mm;
  2. LED holder 3 mm
  3. SPDT switch;
  4. 8-pin connector.

Production of circuits and boards

Working diagram electromagnetic field detector
Working diagram electromagnetic field detector

To supply this chain is used 9V battery, although according to the specifications of the LM358 can use the source voltage up to 32 volts, but then need to use capacitors with adequate rated voltage. Dual power is achieved by a simple voltage divider. The changing magnetic field will induce a current in the two inductors, which are then amplified headphone LM358.

Printed circuit board
Printed circuit board

To create a circuit and the PCB can be used CadSoft Eagle free program. You can make a printed circuit board using "graphical method": print out the PDF file on a transparent foil and then transferred it to the light-sensitive circuit board. Further treated in sodium hydroxide solution and then etched in ferric chloride.

First propaivayut all the elements in the diagram. Then, using wire to connect the potentiometer, an inductor, switch, and LED audio jacks.

EMF detector assembly

If carefully implemented the scheme, it must make the first attempt. The best way to check it out - to bring the device to a working wall adapter, only need to be careful with the volume. This scheme is very sensitive.

After the electronic circuit works, preparing the body, doing it the mounting holes for fixing the board and electrical components.

Neatly stacked all the details of the case and fix it. Then you can enjoy the excellent work of the EMF detector.