Skip to content
Home » Electronics » Electronics Projects » How to make a Cell Phone detector

How to make a Cell Phone detector

    In this article, you will learn how to make an cell phone detector. This cell phone detector can also be called as mobile phone detector or smartphone detector.

    Now, we will make a handy cell phone detector which is able to detect active cell phones near by this circuit.

    Lets make it …

    Components Required for Cell Phone detector

    • BC548 Transistor
    • CA3130 IC
    • 2.2M Ohm Resistors – x2
    • 1K Ohm Resistor
    • 100K Ohm Resistor
    • 47pF Capacitor
    • 0.22uF Capacitor
    • 100uF Capacitor
    • RED Color LED
    • 9V Power Supply

    Cell Phone Detector Circuit

    Cell Phone Detector Circuit / Mobile Phone Detector Circuit

    Working of Cell Phone Detector Circuit

    The normal AM and FM bands are in MHz frequency so we will able to detect using a normal LC circuit. But in case of cell phone frequency it lies between 0.9 to 3 GHz. Here in this circuit we have used CA3130 IC which offers high speed performace, high input impedance and very low input current. The 0.22uF capacitor connect at input of CA3130 plays a vital role in the circuit. Here 0.22uF is used to capture RF signals and the capacitor leads acts as antenna for the circuit.

    The 0.22uF capacitor stores the energy in it and the stored energy is applied at input of the IC. The circuit design is in such a way that, the input is balanced and output of the circuit is approximately zero.

    When ever a mobile phone is active at circuit it distrub the electromagnetic field around the capacitor and makes it to discharge. This discharged energy flow into the input of the IC, which leads to flashing of LED.

    Construction of the Circuit

    This circuit is easy to build as there are less number of components, but the circuit is very much sensitive to electromagnetic field around it. Using a breadboard or vero board may not give desired output as they can induce unwanted capacitance and resistance into the circuit.

    I recommend you to use a PCB which have protective coating on it. I have already designed a PCB for you, which can be downloaded from the following link.

    Download Cell Detector PCB Gerber files

    That’s it guys be creative and enjoy the projects.

    If you have any queries feel free to reach us on social handles Facebook