QSome universities use cellphone-dampening devices in their classrooms to block all cellphone signals. Are these devices affordable for the home user and, if so, where would you find one for purchase?



ACellphone jammers are radio broadcasting devices that block cellular phone calls within a radius of 30 to 160 feet. They are illegal in the U.S., and I can't find any news reports of jammers being used in U.S. universities.

However, you may have read earlier this month that researchers at Anna University of Technology in India have developed a low-power jammer designed to prevent drivers (but not their passengers) from using a cellphone while a vehicle is in motion.

It's unclear whether cell jammer technology will ever be adopted in this country. The Federal Communications Commission (FCC) says "it is a violation of federal law to use a cell jammer or similar devices that intentionally block, jam, or interfere with authorized radio communications such as cell phones, police radar, GPS and Wi-Fi." See tinyurl.com/8296prf.

Why the strong stand against jamming wireless calls? The FCC says that "jammers not only disrupt authorized radio services, but also jeopardize critical public safety communications, such as 911 calls, and could compromise law enforcement efforts."

QMy Vipre security software worked great on our existing computer, but it slowed our new laptop so much that I uninstalled it. What should I do?


Carver, Minn.

AThe slowdown is likely the result of installing the Vipre security software on a PC that already had antivirus or firewall software.

How did that happen? If you bought a new computer, Windows's own firewall is probably "on" by default. In addition, a new computer probably also has some antivirus software, typically a trial version that lasts a few months.

Before installing Vipre again, eliminate the firewall and antivirus software you're using now. Go to Start, click Control Panel and then click "action center." On the right side of the screen, click the arrow next to "security" for a list of active firewall and antivirus programs.

If the Windows firewall is on, turn it off by going to start, Control Panel and then clicking on the icon for "Windows Firewall." Click "turn Windows Firewall on or off." Uninstall an active antivirus program by going to Start, choosing Control Panel and clicking "Programs and Features." Highlight the antivirus software in the list, right click it and choose "uninstall."

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