signal jammer is a device that blocks reception between signal towers or mobile phones. Developed for use by the military and law enforcement, these devices were created to combat threats like cell phone-triggered explosives and hostage situations.


How do signal jammers work?

Known as cell phone jammers, signal blockers, GPS jammers, or text stoppers, a cell phone signal jammer holds up the radio frequency in a given area, creating a sort of signal traffic jam that blocks all communication. Like a radio silence bubble, no calls or texts can be sent or received as long as the user is within range of the cell phone signal blocker.

Are signal jammers legal?

If the prospect of a cell phone signal blocker sweeps your imagination off to the secret machinations of an evil Bond villain plotting away in his lair, you’re not alone. That’s why —you guessed it — it is illegal to sell, advertise, distribute, or operate cell signal booster jammers in the United States, as well as much of the world.Because mobile signal jammer devices intentionally interfere with “authorized radio communications”, the FCC believes that cellular and WiFi signal jammer devices “pose serious risks to critical public safety communications, and can prevent you and others from making 9-1-1 and other emergency calls… (and) also interfere with law enforcement communications.”In addition to public safety concerns, radio frequencies are legally protected by The Communications Act of 1934, which outlaws interference with authorized radio broadcasts.

why are signal jammers used?

Proponents of the technology argue that signal-jamming devices are essential in many places where humans seem unable to follow widely accepted rules of proper cell phone etiquette. Think school, theater, vehicle, or other quiet train trips… just about anywhere were talking, texting, streaming, etc. can be seen as disruptive or even dangerous.Keep in mind that mobile signal jammers don’t just block voice and text on your phone, they can also interfere with GPS, WiFi, and perhaps most problematically – police radar. That’s why, as mentioned above, the federal government bans the sale, promotion, and use of cell phone jammers in the United States. So if you want a little peace of mind with your shiny new signal blocker, you might just have to settle for earbuds.

Does a signal jammer block a signal booster?

Unfortunately, yes, a mobile signal jammer will interfere with your signal booster. Signal boosters work by amplifying an existing signal, but if that cellular signal is blocked, it doesn’t matter how strong it is — the signal jammer will run interference.

How do I detect a signal jammer?

The most common symptom of cell phone signal jammer interference is, you guessed it, dropped service. While apps do exist that claim to detect signal jammers, they are largely unproven and require a working signal to function. Without highly advanced, military-level technology at hand, it is virtually impossible for the average consumer to definitively detect a cell phone jammer.However, if you suspect illegal activity of this sort, contact law enforcement or file a complaint with the FCC.


Cell phone jammers have both benign and malicious uses. Police and the military often use them to limit or disrupt communications during hostage situations, bomb threats or when military action is underway. Portable personal jammers are available to enable their owners to stop others in their immediate vicinity (up to 60-80 feet away) from using cell phones.
Similar equipment is manufactured to block signals in environments where cell phone activity may not be desirable, such as theaters, churches and operating rooms.