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FCC Issues Forfeiture Notices to Two Business for Jamming Cellular Frequencies
An anonymous reader writes "The FCC, responding to anonymous complaints that cell phone jamming was occurring at two businesses, investigated and issued each a Notice of Apparent Liability for Forfeiture and Order (NAL). You can read the details of the investigation and calculation of the apparent liability in each notice below. Businesses engaged in similar illegal activity should note the public safety concerns and associated fines. From the article: 'The FCC issued a Notice of Apparent Liability for Forfeiture and Order to each business: The Supply Room received an NAL in the amount of $144,000 (FCC No. 13-47), while Taylor Oilfield Manufacturing received an NAL in the amount of $126,000 (FCC No, 13-46).'"
Are you sure? I did a little research and found this:
http://transition.fcc.gov/eb/jammerenforcement/jamfaq.pdf
"Jamming devices, however, are ineligible to receive a grant of equipment authorization
from the FCC or an FCC ID. (The FCCâ(TM)s Office of Engineering and Technology oversees
the authorization of non-jamming equipment that uses the radio frequency spectrum.
More information is available at http://www.fcc.gov/encyclopedia/equipmentauthorization.) "
Not that any business could buy.
They are part of the cellular infrastructure.
In contrast to typical land-line phones, cell phones have no "side-tone". Side-tone is the portion of the audio signal from the microphone routed to the receiver (earpiece). By having side-tone we have feedback relating to how loud we're talking and the signal going to the other end. Without the side-tone, there is a natural tendency to talk louder. I don't know why cell phone designers have not incorporated side-tone. The amount of power it would consume is very small.
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
I'm an RF engineer. The device that can decode 2G (GSM and CDMA) , 3G, and LTE signals, understand which are 911 and block the rest, is called a celltower.
The radios and brains to do all three consistently correctly for the full bandwidth of available spectrum would be a toy with a price tag comfortably into the 5 digit range.
If you actively block (using a powered radio-frequency transmitter) in the USA, you are in violation of FCC regulations. Prepare for the government to come at you and take your money. If you passively block through construction materials and techniques, that is 100% completely legal. There are special wall papers, paints, wall boards and other materials that can passively block radio waves. Also, incorporating steel into the construction also inhibits radio signals.