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GSM phone "jammer"

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solvarg

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Iwould like to build a device that could jam, break a GSM call. A short range 2-4m RF transmitter able to disturb (break up) a phone call.
Any one seen a thing like this?
Any one has an idea on how to design one?


Thanks!
 

ME

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Are you aware that such a jammer is illegal in most countries?
Regrds - ME
 

flatulent

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other methods

A fully legal method would be to shout out "Diarrhea of the mouth indicates constipations of the brain." as you point to the person on the phone.
 

E-design

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solvarg said:
Iwould like to build a device that could jam, break a GSM call. A short range 2-4m RF transmitter able to disturb (break up) a phone call.
Any one seen a thing like this?
Any one has an idea on how to design one?


Thanks!
Very easy. You need a VCO that you sweep with a sawtooth around the center frequency of the GSM phone's receive frequency. You can add a small amp on the VCO output to buffer and give a bit of amplification. The VCO is swept at a few KHz with enough amplitude to cover the GSM receive frequency bandwidth.

I was involved in the prototype design of a dual-band unit for a government agency in Brazil and our unit could block and terminate any phone call in a 70m radius.

As the previous member said, this device is illegal in a lot of counties and I am only aware of about 8 that allows the use of this in restaurants and theatres.

E
 

solvarg

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Just an tout

I need a schematic, anyone?
Would I be possible to use an old scraped GSM phone? I that case have anyone seen a phone schematic lying around?
 

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