Since January 1, 2018, importing and owning a jammer has been strictly prohibited in Switzerland and the countries of the European Union. The regulations for these devices, which are also known as "signal blockers" or "jammers", have been tightened up because the ban previously only applied to placing them on the market and using them. Jammers can be dangerous because they block all cell phone traffic, making emergency calls impossible. Most of the time, advertisements for these types of devices are deceptive: they give the impression that their use is legal, and fail to make it clear that even possession is illegal.

Previously expensive, bulky and limited to neutralizing mobile phone traffic in the GSM 900 MHz frequency band, portable jammer have followed technological developments. They have become smaller and cheaper and can now interfere with a large part of the spectrum. With some models, not only mobile phone bands (GSM, UMTS, LTE, ...), but also positioning systems (GPS, Glonass, Galileo, ...), data transmission networks (WLAN, RLAN, WiMax, ...) or wireless alarm systems to be disturbed. Utilization has also evolved. While in the past the devices were only used to stop cell phone conversations on trains, restaurants or cinemas, today they are also used for criminal activities: theft of cars or trucks transporting valuable goods (by disabling the vehicle's tracking), theft in houses and homes (by neutralizing the wireless alarm system), etc.

Due to the spread of jammers, the law had to be tightened: When an amendment to the Telecommunications Act (TCA) came into force on January 1, 2018, the import and possession of drone jammer was prohibited. The manufacture, offering, making available on the market, commissioning, creation and operation of these devices also remain punishable.

With the ban of this type of installation on its national territory, Switzerland follows the EU member states and other countries such as e.g. B. the United States.

A security hazard

The use of jammers is strictly prohibited, as they not only cause inconvenience to radio spectrum users and encourage criminal activity, but can also have serious security consequences. In this way, emergency calls in the event of an accident or the alerting of emergency services such as the fire brigade, police or ambulance can be blocked. This can also cause serious problems in civil aviation, which is increasingly using the Global Navigation Satellite System (GNSS) to improve navigation performance and air traffic control monitoring activities.

In the FMG, the use of gsm jammer is tantamount to intentional interference with the radio frequency spectrum, which can be punished with a fine of up to CHF 100,000. OFCOM systematically intervenes in such cases

Jammers for authorities

It is different in prisons. Detainees use their cell phones to organize criminal activities or plan an escape. Another example is defusing explosive objects that can be detonated by radio. The FMG expressly provides penal institutions and police authorities with the option of using jamming systems to prevent mobile phone calls in their vicinity. The operation of such a system must be approved in advance by OFCOM.