Mobile Phone Call Indicator using Simple Electronics!

Mobile Phone Call Indicator using Simple Electronics!

Here we will discuss, how to make a mobile call indicator using simple electronics. We use 7555 IC with 8 pins outs and a 1.5v cell as battery. This project pickup call within a range of 5cm around the coil. This circuit will turn on the LED whenever a call arrives in a mobile phone within the range. You can make the coil by your own the only condition is that it should have 130 to 150 turns with 0.2mm gauge and coil should have 5cm diameter. You can submit this simple project for your school exhibition. Now let's Start...

Components Required for this project

IC 7555, BC547, 100kΩ, red LED,1N5817,3.9kΩ,1MΩ, 0.1μ, 220μ  etc

The figure below shows the circuit diagram of this project

A mobile phone call indicator can be created using simple electronics using the following basic components: a resistor, a transistor, a LED, and a few connecting wires. The working principle of this indicator is as follows:

  1. The mobile phone sends a signal to the indicator when a call is received. This signal is received by the indicator through a coil.
  2. The signal received is weak and needs to be amplified. This is done by connecting the signal wire to the base of a transistor through a resistor. The resistor limits the current flowing into the base of the transistor.
  3. The amplified signal at the collector of the transistor is fed to the LED through a current-limiting resistor. The current limiting resistor ensures that the current flowing through the LED does not exceed its maximum rating.
  4. When the mobile phone receives a call, the signal is received by the indicator, which amplifies the signal and switches on the LED. The LED remains on until the call is answered or the caller hangs up.

Overall, the mobile phone call indicator works by receiving a signal from the mobile phone when a call is received, amplifying the signal using a transistor, and using the amplified signal to switch on an LED. This simple electronic circuit can be easily built and effectively indicates incoming calls on a mobile phone.

Thank you For Reading😀.....

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