Signal jammers produced today are divided into stationary and portable. The first one works using the network or other power source (the same cigarette lighter in the car). They work mostly indoors to ensure the secrecy of negotiations, to keep theatres and museums quiet, and to eliminate the possibility of cheating during exams. The second size is much smaller and they usually work on batteries or batteries. They have a smaller range. They are also used to counter the recording of conversations, as well as to turn off communications at home (for example, when children talk too much on the phone) or on the road (overly chatty passengers can interfere with the driver).
One of the required signal jammer models is a device from EaglePro, which manufactures both types of jammers.
In this case, EaglePro "Wall" and EaglePro "Tsunami" need to be selected.
The "wall" blocks cellular signals and other channels (Wi-Fi, 3G, 4G) on which the phone works. Can operate in a radius of up to 40 meters. Different small size, it is imperceptible, has no problem and fits almost any interior. Against the background of all this, it's cheap - about 9000 rubles.
"Tsunami" is characterized by the suppression of more frequencies, including radio channels. The coverage radius of the territory is more than doubled (up to 100 meters). Equipped with remote control antenna. But at the same time, the overall model is quite large and much more expensive.
In terms of high-quality signal suppression, the second option seems preferable.
In this category, EaglePro produces several models, of which today's most popular are "Shield 2" and "Metel - Z".
Users who need to suppress the GLONASS signal in the GSM standard also need the "Shield 2". Also, they block the fuel sensor signal. The tiny suppressor (looks like a USB flash drive) operates from mobile phones, radios, and other devices with a USB output. It costs from 3 to 3500 rubles.
In addition to GSM and GLONASS, the modifications to the Shield 2 suppress 3G and Wi-Fi from the standard. Interestingly, the signals can interfere both together and individually. Working distance up to 15 meters. Estimated at 8000 rubles.
"Metel-Z" is used for multi-frequency signal suppression, including GLONASS and 4G, which no other jammer can boast. Coverage radius up to 25 meters. They are not cheap (about 12,000 rubles), but the reliability justifies itself.
What to choose?
It all depends on the problem you are trying to solve. If the goal is to prevent office eavesdropping or prevent material transmission in exams, then the stationary model is more suitable because it has a wider range and suppresses more frequencies.
For personal purposes, the portable model looks more appropriate.
In any case, before buying, you should consult an expert who will assist you with your requirements