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Requirements for GSM jammer design

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arunragavan

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Well as a small project one of my frnds wanted to design a GSM jammer circuit.

What wud be the requirements for such a design. He wanted to know more abt this ckt..

is it possible to jam CDMA signals.. as per my knoledge GSM operates at low power so it wud difficult to jam those signals.. as they do not fall between the high power bands.

can someone help me reg. this GSM jammin ckt and the basic requirements..

with regards,
 

gsm jammer schematic

I do not remember from where I got this but maybe it is a start ...

Please note that in most countries jammers are illegal!!!!

best regards
 
build gsm jammer

What is "jammer"?


gorkin
 

how to make gsm jammer

jammer is a device which block calls in cell phones. it genarate high frequecy noise signal which should be destore / disconnect the calls in cellphone. we can hear any sound when hammer is place near u.
sound like FM signal hear in ratio.
bye
 

cdma jamming

is it really possible to "jam" a digital signal from GSM phones?
 

gsm jammer

Yes

This is possible for limited area.
 

make gsm jammer

What are the following parts on the schematic:

M2 28 x 400
L6 No part number given
947T IC? Module?
 

gsm jammer scheme

well dude it is possible to jam only GSM Signals and not CDMA.. coz CDMA can never be jammed thats the nature of such phones..low power..

with regards,
 

gbppr.org

" it is possible to jam only GSM Signals and not CDMA.. coz CDMA can never be jammed ... "

Unforunatelly not true. Any communication system can be jammed. To do it with CDMA you need approx 20 dB more power as for GSM for the same distance, but if you want to do it in your room... (but it is illegal, too)
 

simple gsm jammer circuit

can any one give me detail ckt about the components and the related data on JAMMER. i m doing a project on this . please help me
byom
 

how to make a gsm jammer

is there any easy GSM Jammer to built to cover 10*10 Meter Area ?

and i need more details about the jameer here in this topic , details about the components whitch you used to make your Jammer circuit

Regards
 

circuit gsm jammer

Where can I get the details of the circuit? can you post it here?

thanks in advance
 

gsm jammer pdf

To do it with CDMA you need approx 20 dB more power as for GSM for the same distance, but if you want to do it in your room... (but it is illegal, too)

In case that you use narowband signal for jaming, indeed you need 20dB more power. If you use jaming signal with bandwith comparable with CDMA signal you didn't need more power. That is theory...
In real world, you allways will have 20 dB( and many more) in close field over CDMA signal, because he is very weak.
 

gsm jammer pcb

i think every system need different technique for jamming

GSM needs a sweep carrier that sweeep all the workin GSM band fast...

CDMA need a CW or narrowband noise!!

Added after 4 minutes:

check this website ...it has a detailed project with pictures abotu how to construct a GSM jammer for the 900mhz band :

**broken link removed**
 
schema jammer

hi, just thought I'd butt in here,

I'll for-go the 'moral' issues raised by this, and the warnings of legality, since it would be breaking the law. Most countries come down very heavy on such actions, not just 'radio' emissions, but specifically phone interference. Safe to say, I strongly disagree, on many levels.

You're all talking about GSM, off the top of my head, second generation mobiles (most common) work on 900 and 1800Mhz. Uplink and downlink are separated by about 50Mhz, band width is 25Mhz for 900, and 50Mhz for 1800. CDMA phones are very tolerant to interferers, but they can be jammed, just like you 802.11b LAN can be jammed, although the spreading sequence in CDMA and code are significantly longer. All these systems have hopping capability, and will hop anyway from time to time to spread network traffic (no-one has the same channel for long). If you are near a base station that has both 900 and 1800Mhz capability, and you want to jamm all mobiles in a specific area, you would need two separate transmitters. OR - A big, fat, dirty transmitter that spits out harmonics like their going out of fashion :)

Although all mobile GSM systems are really good at coping with this, you wouldn't have to damage the radio links too much for mobiles to stop working. Most phone companies would rather cut you off than give you a 'bad line'. peoples phones would still show they have coverage, but they would be unable to make or recieve a call.

My advice would be, keep it simple. You want a wideband transitter to nail either the uplink, or downlink. (I would go with downlink since the signal from the phone is strong, and the signal from the BS is weak, and you would be nearer to the phones). Also, let there be harmonics, specifically, 2nd order (double the centre frequency), that way you can get 900Mhz and 1800 at the same time. So just build a FM transmitter, feed it with noise to randomise and spread the band, and don't bother with the usual hassle of reducing emissions. Sharp edges in your PCB, no shielding, and lots of power (3-5watts?). No point in complicating it, unless you want to 'eaves-drop' in which case, it becomes an electronics nightmare.

Still disapproving,

BuriedCode
 
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