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Cell Phone Jammer Circuit Design is so simple - RF Cafe Forums

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Post subject: Cell Phone Jammer Circuit Design is so simple Posted: Thu Sep 22, 2005 5:53 am


Joined: Wed Sep 21, 2005 3:40 am
Posts: 10
Location: Islamabad,Pakistan.
I would like to explain the design of cell phone jammer.Cell phone is actuelly a two way radio i:e we can send and receive signals of different frequencies.The all you need to design is:
VCO (Voltage Controlled Oscillator)
1650 – 2050 MHz
TL074 Quad Opamp
78L05 Voltage Regulator
9 Volt Power Supply
Here you will generate the radio waves using VCO and apply that output signal to operational amplifier to amplify that signal.A voltage regulator is used which controls the operation of oscillator circuit and 9v power supply is used to operate our final circuit.When the waves are generated and amplified,you will need a small antenna which transmits these waves in the range of 60-80 meters.When any one enters in this range and he receives a call whose frequency is inbetween 1650-2050 MHZ,our generated signal and origional signal collide and cancle power of eachother. So no input is detected by cellular. No service message is always there on that cellular.
NOTE:You can also block any FM radio but you need an oscillator which generates waves in range of 88-108 MHZ.

Design It and Enjoy

Naveed Nawaz
Hamdard University Karachi,
Islambad Campus,Pakistan.


Post subject: Posted: Thu Sep 22, 2005 9:35 am


Joined: Mon Jul 18, 2005 4:31 pm
Posts: 32
Location: Baltimore, MD
Anybody else think that Naveed is now on the list?


Post subject: Posted: Thu Sep 22, 2005 11:49 am
But at what point do we soak our hands in acid?


Post subject: Posted: Thu Sep 22, 2005 12:35 pm


Joined: Wed Aug 20, 2003 11:47 am
Posts: 47
Location: Santa Barbara, CA
Wow, I didn't know a TL074 opamp could be used in the 1650-2050MHz band!! Thats one good opamp!!

Posted  11/12/2012
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