GPS JAMMING TRACED TO TV ANTENNA PREAMPLIFIERS
It was a mariner's nightmare at times in Monterey Bay's Moss Landing
Harbor when unwanted interference effectively rendered global positioning
system receivers useless for hours at a time. Local engineers, sometimes
assisted by federal authorities, launch a furtive search for the source of
the jamming, ultimately locating three almost identical VHF/UHF television
amplifiers with built-in preamplifiers. (GPS World via CGC Communicator)
http://www.gpsworld.com/gpsworld/con...l.jsp?id=43404