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Mobile Phone – Cell phone jammer

Isnt it annoying when the cell phone rings in a movie theater? With modern technology, this disruption is able to be prevented. A device called a cell phone jammer is actually able to block signals being sent from a cell phone to a base station, thus preventing any communication between two parties. They are extremely useful in location where noise is considered a disruption, such as in libraries, movie theaters, school lecture halls, and conference areas.

There are also other uses of the cell phone jammer that could come in handy. For instance, with the number of teenagers using cell phones today, it is becoming more convenient for these students to cheat on tests or homework assignments via text messaging. However, this capability could easily be prevented if schools implemented the cell phone jammer devices in their facilities. Government offices have even considered utilizing the devices, as they would aid in preventing any suspicious activity that me occur in the controversial atmosphere.

Primarily, these jammers were used for government purposes only, especially to counteract terrorism and hopefully intercept calls being made between suspects and known criminals. However, with recent technology (and a higer demand to prevent cell phone activity), the devices were eventually released for private use. As a result, the demand for these units has steadily risen over time, and they are more commonly used in metropolitan areas.

Basically, these devices send out radio waves at a frequency similar to those of cell phones, thus creating a disruption in the signal. Typical phone frequencies range from 800MHz to 1900MHz, and some of the smaller jammers are able to disrupt any cellular device that transmits at this level. However, certain larger, more expensive models are actually capable of interfering with the base cell phone towers themselves, which can cause interference for up to several kilometers. In particular, the TRJ-89 jammer can block signals from an 8km (or 5 mile) radius.

To counteract the signals, cell phone companies have manufactured digital units that have fluctuating frequencies, thus making it more difficult for the jammers to disrupt any signal. In addition, the effectiveness of the jammers is based on several factors, which include level of elevation, location (being indoor or outdoor), and population of a given area. Active temperatures and humidity levels can also play an impact in how effective some of these jammers can be.

Considering that these units can interfere with radio signals, they may or may not be legal in your area. They are completely illegal to manufacture, operate, import, sell, and distribute in the United States, and penalties can be up to $11,000 in fines and up to a year in prison. They are also illegal in Australia, Belgium, Canada, and in the UK. France recently passed a law in 2004 legalizing the use of these jammers in movie theaters. Mexico utilizes these devices only in certain locations, such as churches or movie complexes.