How To Create Your Mobile Phone Signal Jammer. Cell Phone Jammers – Instructables. How to Make Your Own Cell Phone Jammer

One of the finest cellphone jammers available today, The Silencer effectively shuts down both quad band GSM and 3G cellphone signals - it even disrupts older CDMA mobile phones for silence all around, all the time!

How does it work?
The Silencer full spectrum cellphone jammer transmits low power radio signals to cut off communications between cell towers and any cell phones in the proximity. It does not interfere with anything other than mobile phones within a 30 meter working radius!
What types of cellphones will it disrupt?

The Silencer full spectrum cellphone jammer has been specifically tuned to disrupt these cell phone frequency ranges:

§ 850-960MHz (CDMA, GSM)

§ 1805-1990MHz (GSM)

§ 2110-2170MHz (3G)

Silence Is Golden
Just power up The Silencer and within seconds, all nearby mobile phones will lose their network signal allowing you to:
§ Watch the movie in peace

§ Enjoy your dinner in a restaurant

§ Conduct efficient meetings

§ Deliver effective presentations

§ Attend Worship/Mass without interruptions

§ Concentrate on the lecture being delivered

§ Spend some quiet time in a museum or art gallery

§ Read quietly in a public library

§ Stop your students from cheating via SMS texting

And the instant you turn this jammer off, all cellphones will automatically re-establish communications and provide full service. While you may have seen plenty of mobile phone jammers before, this one is quite simply one of the best we have ever tested in terms of reliability and construction. Brought to you by the China wholesale dropship electronics leaders - Chinavasion.
At a Glance...

§ Quad band GSM, 3G, and CDMA cellphone disruption

§ No setup necessary; turn on and it immediately begins to jam localized signals.

§ Instant 30 meter disruption radius

§ Internal Lithium Ion battery

§ Effectively shuts up loud cellphone users in public places!

Note: Mobile phone signal jammers may not be permissible to import into certain countries due to licensing of broadcast signals or other restrictions. Please check your country's telecommunications regulations before placing your order. You should know however that in many countries, including the USA, they are illegal and subject to large federal fines and possible criminal prosecution. Who knows what you might interfere with.

This signal jammer uses 800MHz frequency to operate because many cell phones are working on the same frequency. So I chose the sweeping oscillator as my VCO. It is really efficient yet may be difficult to use if you are beginner without some semi-professional RF-testing tools.

The clock oscillator (45MHz) is driving a local oscillator port as my noise source and is located on the mixer of the mini circuit. To equate the impedance of a clock oscillator with the mixer there is an impedance matching network. Local oscillator signal goes through this network and impedance is matched.

The 800MHz antenna from the old cell phone is connected to the RF input (mixer port). The RF output then goes to the amplifier located on the mini circuit.The amplifier will increase produced output by 15-16dbm of pure power. The empowered signal is going to another old phone antenna.

GSM800 cell phones have their frequencies separated by 45MHz exactly. So when any cell phone tries to make a call - it becomes blocked by itself! The phone talker will hear its own voice.

You can also keep in mind that this cell phone signal jammer can block all cell-based trackers which use your car GPS to track you down and record the data.Even IEDs are probably could be jammed, at least those ones controlled by cell signals.

I used 600MHz mixer but it works nice due to some electronic interferences.
The amplifier is really a must for this device even considering its power consumption.
The case is made from aluminium box for better heat loss.
UHF connectors were attached to the mini circuit because they are perfect for antennas to fasten.
Voltage regulator is required for the nine volts battery to convert voltage.
The battery located inside and separated from other details using foamed plastic.
Do not forget to place the power switch (it may seem obvious yet it is easy to forget).
The antennas from my old Motorola cell phone but you can use other models.

Know how it works. All cell phones which use GSM800 have their transmitted and received frequencies always separated by 45MHz. So when the mobile phone tries to call, it is blocked by its own signal returning to it! Isn't that cool? When the phone blabber annoys you – turn your jammer on and that wrongdoer will hear own voice in his or her cell phone.

· Oh, by the way, you can also use this mobile signal jammer to block any cell-based tracking systems which use your GPS to track and record your car's moves. And it is quite possible to jam IEDs which detonated using cell phones.

· The mixer used is designed to work up to 600MHz but in this case it works pretty well.

· RF amplifier is doing its job perfectly yet draws additional power.

A Pocket Mobile Jammer is a device that blocks transmission or reception of signals, usually by creating some form of interference at the same frequency ranges that cell phones use. As a result, a cell phone user will either lose the signal or experience a significant loss of signal quality. The Pocket type of mobile signal jammers where the mobile network signal can be nil to a particular surrounding when the kit is switched ON. It is a battery operated and in the size of the mobile where we can handle it very easily.

The new arrival in the market is the Hidden Mobile Jammers where the signal has to be jammed in the area where the kit to be confidential means this type of jammers can be used. It looks like a design lamp, where 4 LED's will glow, but very powerful to jam all the 4 frequency bands.

The five modules of Antenna Fixed Mobile Jammers is fixed to certain distance according to the external signal strength. The portable equipment case is equipped for the cell jammers system for the protection purpose. The cell jammers can be mounted on the car or some other temporary places.

The heat dissipation of the cell jammer system is good due to the body fins. The ultra high frequency broad band interference technology, big jamming range and valid subsection are the main features of this cell jammer system. The cell jammers can disrupt the down-link frequency and will not affect the base station. The export device and slow start circuit design can ensure the safety use of the cell jammer system and avoid the sparkling of the mechanical switch.


· Cell Phone jammer for GSM CDMA DCS PHS, range up to 5m

· Mobile 3G/GMS/CDMA and cell phone jammer with a extremely long jamming range of up to 5 meters.

· If you are sick of all those phones going off, or being tracked everywhere with 3G, this is the anti-spy gadget you have been looking for.

· Isolating Signal Bandwidth - GSM/CDMA: 850~960Mhz - GSM/CDMA1900: 1805~1990Mhz

· Typical Coverage: about 22 square Meters (depend on your local signal intensity)

· Average Output Power: 10 dBm

· Typical Battery Life: 2 Hours

· Power supply: Built in Rechargeable Li-ion battery

· Dimension: Antennas off - 97mm x 45mm x 19mm (L x W x D)
How To Create Your Mobile Phone Signal Jammer. Cell Phone Jammers – Instructables. How to Make Your Own Cell Phone Jammer

Mobile phones now are widely used and the normal frequency and common bands includes GSM, CDMA, DCS and PCS. And now with the fast development of the high technology and the 3G signal also come into the market. And such kinds of frequency bands are widely used in the countries all over the world. As these communication mobile phone frequency bands make it possible for people worldwide communicate with each other easier, a lot of people also suffering from the negative effects of the mobile phones. So the mobile phone jammers can help people a lot in this case.

How the cell phone jammer working to block the signals of GSM, CDMA, DCS, PCS or 3G ? This is as the cell jammer is an equipment can prevents mobile phones from receiving and sending mobile signals to the station nearby. Working in this way the signals within the jamming frequency of a certain mobile phone signal jammer can be blocked and lost its ability of making phone calls and sending messages outside. And people in the jamming distance area will not be disturbed by the loudly phone calls and keep good condition in quiet thinking.

Thus as some tracking device also using the mobile phone signal to achieve the goal of stealing the privacy of other people, which is really a great risk to people's normal life and if using the mobile jammers, the signals of the mobile phone frequency bands can be easily blocked and soon the tracking device will lose it function and people's privacy can be protect just by using the mobile signal blockers.

There are also various kinds of mobile phone jammers, and each of them owns the characteristics of themselves, and you can just choose that that according to your real situation and your requirements. And here we hope our team can offer you the best choice and service.

Going 3-Way

At first you should know that there are three ways of jamming mobile phone signals:

· Spoofing (a fake signal is send to the device and the device turns itself off or gets another malfunction)

· DoS (denial of service, when signal band gets filled with radio junk which takes place of normal signal and don't let it in or out)

· TEMPEST (EMF) shielding (covers an object with bubble shielding all incoming and outgoing signals)

Our specialists are using the second one and that is why: spoofing is a nice method but it requires precise adjustment and control, though it may be quite hard to operate for untrained user. The EMF shielding is cool in general but it is bound to one location, so you can forget about any kind of portability.

Thus DoS remains the best choice due to the ability to jam all mobile devices of selected frequencies in a specified area covered by jammer.

Gathering Parts

To make a nice operating cell phone jammer you will need some details to combine. Among them are:

· Voltage Controlled Oscillator (VCO)

· Tuning Circuit (to select desirable frequency to be jammed)

· Noise Source (commonly built-in in Tuning Circuit)

· RF Amplification Unit (so-called “gain stage”)

· Transmitting Antenna

VCO is the most important among other parts. It is like a heart of your jammer. VCO produces RF signal which will interact with the blocked device. Firstly you must select frequencies which will be used in your signal blocking device. Here is the list of standards:

· AMPS (800MHz)

· PCS (800MHz, 1800MHz and 1900MHz)

· GSM (850MHz and 1900MHz in America, 900MHz and 1800MHz in Europe)

· GPS (1227MHz military and 1575MHz civil)

· Wi-Fi/Bluetooth (2400MHz – 2500MHz)

· RFID (also known as UHF/VHF, 14MHz – 400MHz, 800MHz and 2450MHz)

It is also important to think about its size because you might wish to create a desktop mobile phone jammer or aportable handheld jamming device.

Tuning Circuit can be of two types: open-loop and feedback. Open-loop is quite simple and requires just a few op-amps with additional passive components. It is a sawtooth-wave generator which makes VCO to go from lowest to highest frequency. The feedback is using PLL to adjust the VCO's frequency constantly. For this purpose you need to use microcontroller. It is programmed once and then connected to the VCO, thus it is not adjustable.

RF Amplification Unit is what you need when you wish to increase the area covered by your jammer along with its signal blocking power. The more power has your signal blocker, the bigger radius it jams. The cost is, as you may guess, battery working time. More power equals less time for battery to live.

There is a huge selection of gain stage units on the electronics market (7dbm, 17dbm, even 20+dbm). But consider that more powerful amps are bigger and need better power supply.

Transmitting Antenna is a tool which transmits signals produced by your jammer. The main characteristic of antenna is VSWR (Voltage Standing Wave Ratio). If your antenna has VSWR of 3 or lower, then this is what you need, because the return loss of this antenna is minimal.

Jammer Store specialists use SMA antennas due to their ability of being removed or replaced easily. It is worth to mention that omnidirectional antennas are preferable, unless you like to use your cell phone jammer in a TV remote style.

Power Source makes your creation to become alive. Generally mobile phone jammers use 5VDC to operate. Thus you may use Lithium-ion battery to supply your creation. In the case of using common power source you will need power adapter. The power adapter may be of one of two types: switched-capacitor voltage doubler or inductor-based boost regulator.

The first one is simple and efficient yet not regulated solution, so you will need LDO regulator to fix the voltage. The second one is regulated but it has bigger cost, more complex and requires precise specification of all components to work properly.

Our manufacturing guys use boost regulators for their creations. It takes more time and work but gives better result. AC-DC and DC-DC adapters are made for almost all types of mobile signal jammers.

Additional Notes

· Older generations of mobile devices are easier to jam because of lower working power. Respectively they would be jammed at the bigger distance than modern cell phones.

· More powerful jamming devices might be in need of cooling system to prevent malfunctions.

· If you have enough skills, training and experience (along with specific equipment), you can use programmable PLL with microcontroller to make your cell signal jammer adjustable.

Jamming devices overpower the cell phone by transmitting a signal on the same frequency and at a high enough power that the two signals collide and cancel each other out. Cell phones are designed to add power if they experience low-level interference, so the jammer must recognize and match the power increase from the phone.

Some jammers block only one of the frequencies used by cell phones, which has the effect of blocking both. The phone is tricked into thinking there is no service because it can receive only one of the frequencies.

Less complex devices block only one group of frequencies, while sophisticated jammers can block several types of networks at once to head off dual-mode or tri-mode phones that automatically switch among different network types to find an open signal. Some of the high-end devices block all frequencies at once, and others can be tuned to specific frequencies.

To jam a cell phone, all you need is a device that broadcasts on the correct frequencies. Although different cellular systems process signals differently, all cell-phone networks use radio signals that can be interrupted. GSM, used in digital cellular and PCS-based systems, operates in the 900-MHz and 1800-MHz bands in Europe and Asia and in the 1900-MHz (sometimes referred to as 1.9-GHz) band in the United States. Jammers can broadcast on any frequency. Old-fashioned analog cell phones and today's digital devices are equally susceptible to jamming.

The actual range of the jammer depends on its power and the local environment, which may include hills or walls of a building that block the jamming signal. Low-powered jammers block calls in a range of about 30 feet (9 m). Higher-powered units create a cell-free zone as large as a football field. Units used by law enforcement can shut down service up to 1 mile (1.6 km) from the device.