How To Build A Cell Phone Detector Circuit On A Breadboard

Most of the people known by the word mobile phones, they are commonly used in our day to day life and they are updating the different operating system with different applications. The proposed system cell phone detector circuit is very helpful to detect the cell phone which is in silent mode and at restricted places like examination hall, hospital, and meeting rooms and etc. If the circuit detects the RF transmission signal through an activated mobile phone then it produces the beep sound and the LED will blink. The beep sound will produce until the signal transmission end.

What is a Cell Phone Detector?

The cell phone detector is a detector which detects activated cell phones nearby and gives the indication of activated cell phone surrounded by the detector circuit. Generally, the cell phone detector is a frequency detector and its frequency is about 0.8 to 3.0GHz for mobile band frequency.

Components Required for the Cell Phone Detector Using Breadboard

To build the circuit of a cell phone detector using breadboard the following components are required. Op-Amp CA3130, 2.2M resistor (2), 100K resistor (1), 1K resistor (3), 100nF capacitor (4), 22pF capacitor (2), 100uF capacitor, Breadboard, 9 Volt Battery, Battery Connector, LED, Transistor BC547, Transistor BC557, Connecting wires, Buzzer, Antenna. The following description will explain about the circuit of cell phone detector.

Circuit of Cell Phone Detector Using Breadboard

The following circuit diagram shows the cell phone detector using a breadboard. In this circuit to detect the incoming & outgoing signals of a cell phone, we are using CA3130 op-amp IC. The op-amp noninverting end is connected to the Vcc with the help of 2.2M resistor. The op-amp is also connected to the ground through 100K and 100µF capacitor. Its inverting terminal is feedback from its output through a 2.2M resistor for amplifying the signal. In between the inverting and non-inverting terminal, there are two 100nF capacitors and these capacitors are connected in series to the pin 1 and pin 8 of the op-amp. To increase the gain of the current to voltage converts at its output pin.

At the base of NPN transistor, the op-amp is connected, the name of the transistor is BC547 and for indication purpose, the LED is connected to its emitter. For the indication of the sound, a buzzer is used by using a PNP transistor and the type of transistor is BC557. The 9-volt battery is connected to power supply and reset of connection are shown in the circuit diagram.

Block Diagram of Cell Phone Detector

The block diagram consists of the op-amp, some passive components and LED & buzzer used for indication purpose. The configuration of the op-amp is frequency detector or current to voltage converter and the output of the op-amp is connected to the LED and buzzer with the help of NPN and PNP transistor.

Working of Cell Phone Detector

The working of the mobile detector is very simple. The two capacitors C2 & C3 of 100nF is in parallel and used for detecting the RF signal from the mobile phone. The two capacitors will work like a loop antenna for the system. If any call or SMS are received for the mobile then capacitors are in parallel and detect the transmission frequency or RF signal. To the op-amp the current is generated at the input side, therefore, the output of the op-amp goes low or high. Due to these variations, the LED turns ON and OFF with the help of the NPN transistor according to the frequency signal.

The present movement the PNP transistor triggered with some frequency and buzzer starts the beeping sound until the data transmission gets ended. To the op-amp the current is generated at the input side, therefore, the output of the op-amp goes low or high. Due to these variations, the LED turns ON and OFF with the help of the NPN transistor according to the frequency signal. The present movement the PNP transistor triggered with some frequency and buzzer starts the beeping sound until the data transmission gets ended.

Application of Cell Phone Detector

• It is used to prevent the mobile phones at the examination halls.
• It is used where the mobile phones are prohibited like gas stations, petrol bunks, historical places, religious places and etc.,
• By using this circuit the stolen mobile phones are detected.

Advantages of Cell Phone Detector

• It will detect the hidden cell phones
• The cell phone detectors are smaller in size.
• The operation of cell phone detector is easy
• The power consumption of this circuit is very less
• The response or detection of the mobile is very fast

Disadvantages of Cell Phone Detector

• There is an inconvenience to use this detector for people
• Using this circuit the important calls can’t lift

In this article, we have discussed how to build the cell phone detector circuit using a breadboard and its applications. I hope by reading this article you have gained some basic information about cell phone detector circuit using a breadboard. If you have any queries about this article or about the projects on electrical & electronics please, feel free to comment in the below section. Here is the question for you, what are the functions of the cell phone detector?