Simple mobile detector circuit

Picture of simple mobile detector circuit
simple mobile detector circuit using  CA3130 op-amp

description source:

This handy mobile  phone detector  can sense the presence of an activated mobile cellphone from a distance of one and-a-half metre. So it can be used to prevent use of mobile phones in examination halls, confidential rooms, etc. It is also useful for detecting the use of mobile phone for spying and unauthorized video transmission.

The circuit can detect both the incoming and outgoing calls, SMS and video transmission even if the mobile phone is kept in the silent mode. The moment the mobile  phone detector detects RF transmission signal from an activated mobile phone, it starts sounding a beep alarm and the LED blinks. The alarm continues until the signal transmission ceases.

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Step 1: Components

Picture of components
components list

1, CA3130  - op-amp 
2, PCB
3, Resistors all 1/4W ,
    1.2M Ohm - 1
     2.2M Ohm -1
     1K Ohm -1
     100K Ohm - 1
4, Capacitors
     22 pf ceramic -3
     0.22uf ceramic -1
     0.1 uf  polyester/ceramic -1
    100uF/25V  Electrolytic  -1
5, Red LED -1
6, BC548 -1
7, 5Cm copper wire -1


What if there is no available CA3130 op-amp is there any replacement for that? I hope you can help me with this.

atharva124 months ago
what voltage ceramic capacitors should i use
Jestin_Cubetech (author)  atharva124 months ago
16v generic ceramic capacitor
Jestin_Cubetech (author) 6 months ago
circuit diagram
Where did you insert the buzzer, it's not on schematic ?
Needs an introduction to explain what it is & what it does. Not everyone can figure this out ... many are nubies.
Jestin_Cubetech (author)  Lectric Wizard6 months ago
Thank you for your valuable suggestions.
Much better. I never thought of the security uses. GREAT IDEA !!! CHEERS!

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