Today, it is not a rare thing if you have ever come across a situation that your cell phone signals cannot make or receive any phone call. That is to say, you cannot keep contact with the outside world. However, this is unavoidable because in some special places, you should always keep quiet. On such occasion, a cell phone jammer is needed to be installed.


Actually, the cell phone jammer is a very familiar thing that we can come across in our daily lives. More often than not, when you are a student, you can always see this gadget in front of the room in the process of the exam. Another case is that in some solemn places where quietness is quite necessary such as the church.


Long before, this gadget is only used to refuse unwanted calls such as advertisement promotions. Later and later, as people demands, the cell phone jammer has finally turned to be tool which is used to shield radio signals.