Simple mobile Detector Circuit using Op-Amp

 Simple mobile Detector Circuit using Op-Amp

In this tutorial, i will be able to show you an easy mobile detector employing a cheap LM358 op-amp. This mobile detector can detect the nearness of a lively telephone from a separated distance of 4 to 5 meters. So it can come helpful in an assessment lobby or gatherings where cell phones aren’t allowed.

Mobile Phone Detector may be a Circuit that detects the presence of mobile up to a particular range like 1.5 meter . It detects the phone when an incoming call or outgoing call is formed or when an SMS is shipped or received or any GPRS used.

When the circuit detects an RF signal from an activated mobile , it gives a sign by switching ON an LED. The LED will start blinking and continues to blink until the incoming/outgoing signal stops. mobile detector also can be called as a Frequency Detector. Frequency Detector is just a Current to Voltage Converter Circuit which detects the frequencies in between the range of about 800 MHz to 3GHz.

Components Required

LM358 IC

BC548 NPN Transistor

100 uF/25V electrolytic 

1uF/25V electrolytic 

Resistors (1 KΩ, 220 KΩ, 100 KΩ)

100K Potentiometer



Connecting Wires

5V Power Supply

The circuit is made using LM358 Op-Amp IC and NPN Transistor BC548. you’ll check our previous supported LM358 IC: Over Heat Detector

When a mobile is active, it radiates RF signal within the sort of electromagnetic wave . When the mobile radiates energy within the sort of RF signal, Capacitor C2 absorbs it and used as an input to LM358 IC. The output of LM358 is connected to LED via Transistor which gets turned ON. Then the flashing of LED is observed. The potentiometer RV1 is employed to regulate the sensitivity or range of the circuit. this is often how you’ll make an easy Phone Detector Circuit.

Related posts

Leave a Reply

Your email address will not be published. Required fields are marked *