Category: Tag Block

Mobile phone blocker is a mobile phone blocking program or mobile phone detection system, designed to prevent unauthorized mobile phones while allowing authorized mobile phones to run. Blocking cell phone signals can prevent certain critical foundations, unauthorized calls to courts, military installations, or certain environments that need to manage cell phone activity to control the control.

Please note that in some states, cell phone jammers are illegal. Although attention to information rejection has long been an integral part of the PLA’s doctrine, this jammer is mainly used in military locations or other places where the use of mobile phones is prohibited.

You can use a recording blocker to prevent recording during important meetings!

The most effective means to prevent recording is to generate random noise signals through the recording masker, which can suppress the voice signal, so that the recording equipment picks up only noise information, but cannot distinguish the voice information and cannot restore it from the recorded signal. The original information is output to ensure the security of voice information. The recording blocker adopts security encryption processing, and effectively prevents post-restoration by mixing high and low frequency audio sources.

Jammer-mart has focused on information security for 14 years. The newly developed L7B recording jammer has been upgraded on the basis of the original equipment. The FPGA-based ultrasonic noise algorithm eliminates the high frequency noise of the old equipment. It has joined the brands that have been on the market in the past two years. The information of mobile phones and recording devices has a very obvious effect on new recording devices and mobile phone recording. It is suitable for confidential meeting rooms, public security bureau petition centers, procuratorate reception halls, courts, negotiation rooms, offices and other places for private conversations.

desktop signal blocker

The recording blocker is completely silent when working. The sound recorded by ultrasonic recording and eavesdropping equipment is completely noisy, and no meaningful information can be extracted. Designed with the appearance of ordinary audio. Confidential meeting room, public security bureau petition center, prosecutor’s office reception hall, courtroom, negotiation room, office and other places for private conversation.

Working principle: The recording jammer emits ultrasonic waves with random noise that cannot be perceived by human ears. When digital devices such as mobile phones are recording, these noises are recorded into the digital device together with the sound of normal conversation, making the recorded audio invalid. The audio information in the captured video also has the same interference effect. Because the noisy ultrasonic noise is randomly generated and cannot be restored, the audio after the interference cannot be restored, thus ensuring that the original information is not leaked and spread.

As a new product, recording jammers have received more and more attention and support from people. From the previous government agencies (mainly the public security system and service-oriented windows) to the current enterprises, the needs of enterprises have gradually increased. An important reminder for us. It shows that business people are gradually attaching importance to the safety of voice information and their awareness of self-protection has increased. Imagine if in a conversation scene, if any participant turns on the recording device, or connects the call and keeps it in the call state, the remote personnel can There is no security to hear the content of the conversation at will. In this case, the recording blocker can play a good role in protecting the security of audio information.

A quick and dirty guide to monitoring mobile phones during protests

As riots against police brutality and institutionalized racism swept across the country, many people were exposed to the full power of law enforcement weapons and surveillance for the first time. Whenever protesters, cell phones and police are in the same place, protesters should pay attention to cell phone surveillance. Usually, security practitioners or other protesters respond to this issue through suggestions provided by local law enforcement agencies using cell location simulators (also known as CSS, IMSI catchers, stingrays, earth boxes, hail, fake base stations, or crosses). However, in many cases, this suggestion is wrong, or it is due to fundamental reasons such as not knowing what the cellular base station simulator is, its function and frequency of use.

Denial of service or signal interference is an additional function of CSS. In fact, the FBI has admitted that CSS can cause signal jammer to local personnel. Unfortunately, for the same reasons, it is difficult to determine the use of CSS, and it is difficult to tell how often they interrupt service, whether intentionally or unintentionally. Signal towers that look like signal interference may also be overloaded and disconnected. If many people suddenly gather in one place, it may overload the network, which is not the purpose of the design.

Professional high-power interceptor

How to protect yourself from cellular signals

As we mentioned in our self-defense guide for monitoring protesters, the best way to protect yourself from cellular site simulators is to put your phone in airplane mode and then turn off GPS [2], WiFi and Bluetooth, and cellular data. (Although “receive only” GPS and not lose its own location information, many apps track GPS location data, which is ultimately stored in a database that law enforcement agencies can search for later.)

We know that some IMSI capturers can also intercept content, but as far as we know, if you don’t downgrade your cellular connection to 2G, none of them can do it. If you want to protect your device from this attack, the best option is to use encrypted messages such as Signal or WhatsApp and put it in airplane mode when you find that your phone has fallen to 2G. (There are many valid reasons. Your phone may downgrade some of your connections to 2G, but it is safer than regretting.) However, an important part of the protest may be live broadcast/recording and immediate upload of police reports against protesters. Violent video. This is inconsistent with the recommendation to keep the phone off/in airplane mode. Up to you

Unfortunately, iOS and Android currently do not provide an easy way to force your phone to use 4G only, although developers can of course add it to their operating systems. If you can turn off 2G on your phone, this is a good preventive measure.

Could the police actually shut down a city’s cellular service?

At around 1 am on Monday, a strange tweet claimed that Washington, DC had been disconnected from the digital world. The Washington Post later reported that the Twitter accounts of only three followers were the first to report a suspected interruption. When people wake up and register online, #DCblackout is all the rage in the United States. The hashtag appeared in thousands of tweets, accompanied by reports of explosions, missing protesters and silencers of police rifles. What followed was a brief online chaos: Did the police really block the cell phone tower? What should the so-called failure cover? The local reporter quickly tweeted that they had not experienced any failures, and later that day, the rumors were thoroughly debunked. It turns out that a power outage is the highest level of error message. This also dispersed the interference of local protests. The local police used violent methods against the protesters all night, including pepper spray, rubber bullets and tear gas.

However, the prerequisite for the power outage is that the police (or the federal government) can completely shut down the communication network-this behavior has seriously affected the freedom of speech and assembly rights, as well as the safety of protesters and passersby. Although it did not happen on Monday, the joke raised the question of whether it is possible for law enforcement agencies to cause technical and legal power outages.

Americans tend to view deliberate service interruption as a dangerous strategy used by oppressive regimes abroad. In a speech by the American Civil Liberties Union, Jay Stanley, a senior political analyst for the Privacy and Technology Project, told me that interruptions in communication are often seen as “a terrible form of abuse” and are used worldwide to cover up repression of sexual violence and other violations. Human rights behavior. ”

But this form of censorship has occurred at least once in the United States. In 2011, the Bay Area Rapid Transit System (BART) suspended cell phone service at a subway station in downtown San Francisco after hearing about plans to protest the BART police’s plan to kill a man. The purpose of BART is to prevent protesters from coordinating, but it is short-sighted, thus making the agency the center of freedom of speech controversy across the country. The Federal Communications Commission intervened, and BART’s actions were condemned by human rights organizations such as the Electronic Frontier Foundation (the incident was called the “BART La Mubarak in San Francisco” incident). The FCC investigated BART, but like Harold Feld, the senior vice president of non-profit public knowledge told me that the committee decided not to make a declarative decision on the incident. This boils down to a technical problem: BART actually shuts down the service by shutting down the equipment in the underground system instead of destroying the signal.

No similar incidents have been confirmed since, but in the 2016 Tateishi protests, Wired reported that tribal leaders believed that the police had blocked their phones. The problem with proving these claims is that it is difficult to determine whether malicious behavior is occurring or just a bad signal. Only agencies like the FCC have not yet investigated the claims to truly verify the occurrence of traffic congestion.

The BART controversy and, to a lesser extent, the Standing Rock controversy, both show how complicated the shutdown signal can be in the United States-and how we truly fail to understand and resolve the blueprint for current and future law enforcement blackouts. What we do know is that almost ten years later, it is still possible from a technical point of view. According to Joshua M. Pearce, a professor of materials science and engineering at the Michigan Technological Institute, there are two ways to cause ground blackouts. (Turning off BART is an unusual situation because the authorities can access the device themselves.) The first is to ask (or require) the service provider to shut down a specific set of cell phone towers. It’s as simple as flipping a switch

The second method (and the more difficult method) is to use jamming technology, which sometimes sends false signals, overwhelming the signal from the cell phone tower. Small short-range equipment can be purchased abroad (for example, equipment used by some overseas universities to stop fraud, which led to the suspension of a high school teacher in Florida in 2015). In theory, you can use a large number of such small devices to call neighbors, but this is not convenient. Pearce believes that signal jammer have greater coverage, but only organizations like the National Security Agency own them.

Raspberry Pi 4 HDMI is interfering with its own WiFi

Upgrading a popular line of products may sound like a good idea, but adding bigger / better / faster parts to an existing product can lead to unforeseen problems. For example, putting a more powerful motor in an existing vehicle platform seems to work at first until people report that the increased torque is bending the frame. In the Raspberry Pi world it seems that the “updated engine” in the Pi 4 causes the WiFi to stop working under certain circumstances.

Enrico Zini noticed this problem and tried to reproduce exactly what caused the WiFi to fail. After testing various Pi 4 cards, power supplies, operating system versions, and a host of other variables, the cause was isolated on the screen resolution. Apparently the WLAN fails with the setting 2560 × 1440 with HDMI. While you might think that a SoC might not be able to handle high resolution, WiFi, and everything else that tiny computer has to do all at once. However, the root cause seems a little more interesting than a simple problem with system resources.

Mike Walters checked for a radio frequency problem with a HackRF on a Twitter post on this issue. It turns out that at this screen resolution, the Pi 4 emits RF noise that is exactly in the range of WiFi channel 1. It appears that the Pi 4 is acting as a wifi jammer for itself.

This story is pretty new, so hopefully the Raspberry Pi Foundation is aware of the problem and is working on a fix. For now, however, it might be best to use a slightly lower resolution if you encounter this problem.

Drone jammers to disrupt tactical communication

At the 2019 partner exhibition, the International Armaments and Defense Equipment Fair in Belgrade, Serbia, a new quadcopter drone equipped with a jammer to disrupt tactical communications was shown. June 26, 2019.

At the 2019 partner exhibition, the Military Technical Institute of the Serbian Army, in cooperation with the local company, developed a new quadcopter drone carrier jammer to disrupt tactical communication.

A jammer for jamming tactical communication systems is mounted on a quadcopter drone, which is electrically powered by four electric DC motors and has a maximum flight time of 20 minutes. It has an empty weight of 35 kg and 107 kg with the batteries. It can fly at a maximum altitude of 2,000 m with a maximum range of 6 km.

The jamming system mounted on the quadcopter blocks all communication between the drone and its operator in a frequency range from 30 to 88 MHz, optionally with 512 MHz and an HF power of 50 W.

handheld drone jammer light

The drone jammer represents the drone as a platform for electronic attacks. The jamming transmitter of a drone carrier for disrupting tactical communication is used to block tactical communication by radio devices of all kinds. The range of this jamming transmitter could be increased significantly, i.e. H. The area of interference could be increased many times the distance from the initial ground interference position at which it was started.

Another means of using drone-borne jammers could be the wrong target for ant radiation missiles or a means of deceiving the enemy.

The type and working principle of signal shielding instrument

Recently, frequency jammers have appeared in the automotive and telephone markets. These small devices are used to encode and redirect the frequencies of the waves emitted by an electronic device, either in order not to interfere with certain professions or to serve less available destinations.

The different frequency jammers

There are different types of frequency jammer. More and more theaters and hospitals are using it. Frequency jammers prevent cell phones from receiving waves and receiving and making calls or messages. If this is a means of gaining artist respect for function rooms, it can be vital for hospitals as certain waves distort the results obtained with diagnostic or monitoring tools such as electrocardiograms.

wifi signal blocker GPS

Some motorists also equip their vehicles with frequency jammers so that they are not detected by the police or gendarmerie if the speed limit is exceeded. This is prohibited by law and, if verified, could result in law enforcement and a hefty fine. Frequency jammers are also popular with car thieves, who thus interfere with the frequency of your remote shutdown. They think you have closed your doors and you don’t. The thief does not have to get into the vehicle until you have turned your back.

How do frequency jammers work?

A frequency jammer is not a device that takes up a lot of space because it fits in your hand. However, it is a technological tool. It’s inexpensive but not commercially available. The internet and the black market are the main suppliers of frequency jammers.

These pick up waves with an antenna and encrypt them, i.e. they make them illegible. Some frequency jammers have a long range, but the basic models don’t exceed 40 meters.

Why should public WIFI will be used to lose personal information?

Mass users and fragmented internet habits make public WiFi a mandatory requirement in the mobile age. Thanks to this feature, the WiFi Universal Key, which provides a free network service, has been introduced with 900 million users for four years. Google and Facebook have launched similar services in several regions.

In recent years, however, the media have repeatedly reported theft of user accounts caused by the use of public WiFi. The public has had tremendous fears about the security of the public WiFi: whether the public WiFi is being used, it can lead to the disclosure of personal information and even damage to property?

How did your personal data come out? Maybe you drink coffee, use free wifi and then personal information is stolen. In recent years, free public WiFi has become a hidden danger for citizens to divulge personal information and compromise network security. Therefore, WLAN management in public places has come into focus. Corresponding countermeasures are also currently being investigated.

wireless jamming for sale

Hackers set a camouflage WiFi, a parasite highlight of the signal is very strong, can suppress the coverage of the normal radio signal, set up a cell phone and network dialog between the listening level in the users and the operation of the first one, which passes on your disguise WiFi then , in the WLAN network, your personal data is in a state without data protection. This means that everything you do on your phone can be viewed.

How does the hacker transfer your money over WiFi?

Step 1: The hackers set up free WiFi to allow the victim to access the mobile phone.

Step 2: When disguising the website, write down the password of the victim’s login to the phishing website and personal information.

Step 3: steal user information and steal the victim’s bank card number password.

Step 4: Install victim mobile trojan virus and block user SMS.

Step 5: Use trojan virus to steal cell phone payment verification code and complete the theft.

How do you protect your network security?

First of all, do not connect the unknown wireless network, online shopping, payment and other sensitive operations. It is recommended not to use public WiFi.

Second, the cell phone, computer and other electronic products to kill viruses, install security software, and change the password frequently to maintain security.

Third, using a wifi jammer can effectively avoid automatic access to unknown WIFI, which can prevent your smart device from being attacked.

Fourth, the person’s confidential information must be properly kept, not in email, chat tools, and other places where account password information is revealed. Different websites and systems suggest using different accounts or passwords.

Mumbai: Cell phone jammers could soon appear in BMC theaters

“Something must be done to stop cell phone harassment during the game and performances. Jammers will allow audiences to enjoy the show peacefully,” Mhatre said

Pradnya Dongaonkar, a resident of Dadar, has a complaint that will resonate with most theater and cinema goers. “It’s really annoying when a cell phone rings in the middle of a show. Anyone who violates the norms and instructions to ensure the cell phone stays idle or completely shut down should be fined.” While a fine may be a long way off, there could soon be prevention, at least in civil society-owned theaters.

Citing the fact that cell phone interruptions during live performances in lecture halls and theaters have often become a nuisance, the BMC decided at its general meeting to install signal jammer. The proposal was put up for discussion on July 25, 2019 by Shiv Sena company Shital Mhatre. The proposal, which the BMC has accepted for consideration, is now being announced for suggestions and objections.

indoor phone jammer

“Something must be done to stop cell phone harassment during the game and performances. Jammers will allow audiences to enjoy the show peacefully,” Mhatre said.

But not everyone agrees with the idea. Ajit Bhure, a theater personality who heads the Association of Commercial Game Producers, says, “Sometimes people make mistakes, but nobody does it on purpose. Disturbing an entire theater will cause big problems. It will not network people, it will network Artists cut up for four hours. If there’s an emergency during that time, how do people know? ”Bhure suggested instead creating awareness of mobile manners.

However, once a cell phone jammer is installed in a theater, it is no longer a permanent function. “After the BMC has received the necessary permits from the central government, it will continue with its plans. Even with the jammers installed, the facilities will only be made available if the request is made by theaters and producers, associations or organizers. The The application must be made in writing, “says the administration’s letter.

High quality drone jammers for military applications

Jammer-mart specializes in the production and sale of high quality signal jammers and offers a wide range of jammers for military applications.

Jammers for drones include portable models, desktop models, suitcases, briefcases and models for various purposes.

Other models include bomb jammers designed to protect vehicles from improvised explosive devices (IEDs), prison jammer to protect the area, remote jammers to remove remote controlled devices, and a range of Wi-Fi mobile devices and systems (GSM) jammers for addressing of radio and GSM signals.

desktop mobile phone blocker

Drones disrupt the remote control and GPS signals

Jammer-mart offers a special range of jammers with which the remote control (RC) of an unmanned drone / quadrocopter for aircraft (UAV) or its GPS signal (Global Positioning System) can be disrupted.

Most commercial 3km to 5km high-end UAV drones / quad copters only use 2.4GHz Wi-Fi and GPS L1. All other drones with 5.8 GHz, 433 MHz, 928 MHz can control a maximum length between 500 m and 1,000 m.

We offer devices with proven radio technology and guarantee reliable operation and stability.

Remote controlled jammers series

Jammer-mart is developing a special series of jammers designed to restrict RC signals from various devices including RC cars, boats and toys, as well as quadcopters, alarms and wireless sensors.

Jail jammer for military locations

Prison Jammers are intended for prisons and other large sensitive locations such as military or government buildings. They can also be used in military units, security and intelligence services, oil and gas storage facilities and fields, and in museums.

The jammers can be used to block occupant phone communication if necessary.

Portable briefcase jammers for RC bomb protection

The Portable Briefcase with Radio Controlled Improvised Explosive Device is a portable broadband jamming system that protects VIPs and citizens from radio controlled improvised explosions by deactivating radio signals to control exploders in dangerous areas.

Briefcase jammers emit radio frequency (RF) interference, creating an “RF protected zone” around the object (or a group of objects in that zone) that allows radio-frequency remote activation of bombs (activation of cells / mobiles, radios, and others various radio devices) in the vicinity with a sufficient anti-trap safety radius to save lives and avoid serious injuries.

Vehicle and briefcase jammers also guard police and government offices, security forces, dignitaries and VIPs, checkpoint and border crossings, roadblocks and embassies.

Jammers are available in different models depending on frequency and output power, but can also be customized to meet user requirements.

GPS tracking and location of jammers

The GPS signal jammer models are designed to cover GPS tapes and other tracking and positioning devices to provide an effective combat solution that goes undetected by GPS trackers and Wi-Fi Android tracking devices.

About wretched world

Jammer-mart focuses on the market needs and security trends and then develops drone jammers to meet the growing demands of the security market such as the rapidly growing UAV market.

We supply an extensive selection for every possible application.

Set the distance due to GPS interference

From the construction of offshore wind farms and dredging ports to marine surveying and the laying of underwater cables, GPS receivers have established themselves as a critical element in many offshore and nearshore applications. Downtime in GPS tracking at sea can be dangerous and costly. GPS downtime is increasingly attributed to malfunctions.

The location of a chirp jammer in the car on Shelter Island that was used to simulate the effects of GPS interference on San Diego Bay. GPS signals are transmitted at power equivalent to that of a standard lightbulb. They are expected to travel more than 20,000 km and still be suitable for high-precision position calculations. In most cases, the signals arrive relatively intact, but can hardly be distinguished from the thermal background noise and can be ducks for any passing interferer.

Maritime applications are increasingly using high-precision positioning such as RTK and PPP, which not only use the code information modulated onto the signals, but also the phase of the signal itself. In the presence of interference, these phase-based modes suffer first.

The use of GPS signal jammer is strictly prohibited, but their effects can be assessed using a GPS simulator. Using the example of the port of San Diego, a simulator was programmed to generate the GPS signals that a receiver on a boat would see at that location. The interference of the GPS signals was mimicked by mixing the simulator signal with that of a jammer. With the jammer in the location shown in Figure 1 and the GPS receiver on a boat near the bay, the effect of interference across the bay could be extrapolated using standard models for the propagation of radio waves.

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The results in Figure 2 show that a small 10 mW chirp jammer without AIM + interference mitigation can turn off RTK positioning over several hundred meters. When AIM + is activated, the non-RTK zone in the immediate vicinity of the jammer is reduced to a few meters.

The effect of a 10 mW chirp jammer on GPS positioning in San Diego Bay with and without AIM + interference mitigation.

If you repeat the tests with a Continuous Wave Interferer (CW) of the same power, the results with AIM + are even more dramatic, as Figure 3 shows. Without AIM +, a CW interferer in the parking lot near the coast prevents RTK positioning or GPS positioning over a large part of the bay and extends several kilometers to the sea within sight of the jammer.

The effect of a 10 mW continuous jammer on GPS positioning in San Diego Bay with and without AIM + interference mitigation.

A comprehensive approach places interference issues in the foreground of the receiver design and incorporates them into every phase of signal processing. With the AsteRx4 OEM and AsteRx-U, the antenna signal is digitized immediately after filtering and automatically freed from interference using several adaptive band-stop filters.

Depending on the type of interference, the stop bandwidth is automatically set between a notch of a few kHz to 1 MHz in width. The notch filters are supplemented by an adaptive filter that can suppress more complex types of interference such as chirp jammers, frequency hopping signals from DME / TACAN devices, and powerful Inmarsat transmitters.