Page "Mobile phone jammer" Paragraph 4
from
Wikipedia
Older jammers sometimes were limited to working on phones using only analog or older digital mobile phone standards.
Newer models such as the double and triple band jammers can block all widely used systems ( CDMA, iDEN, GSM, et al.
) and are even very effective against newer phones which hop to different frequencies and systems when interfered with.
As the dominant network technology and frequencies used for mobile phones vary worldwide, some work only in specific regions such as Europe or North America.
Some Cell Phone Jammers have been introduced to some State Prisons in the United States.
Cell phones that have been sneaked into prison pose a security risk for guards and property owners living near by.
Page 1 of 1.
1.944 seconds.