Since 3700kHz is in the
80-meter band used by
ham radio operators, the appearance of an unauthorized and anonymous wide-band signal attracted the attention of many amateur radio enthusiasts from across the country, leading to speculation that the broadcasts were emanating from a type of
numbers station. In February 2005, two
ham operators from
New Mexico successfully used mobile
radio triangulation equipment to track the signal to the
Laguna Pueblo reservation around 50 miles west of Albuquerque, and more precisely to the Mobility Assessment Test & Integration Center (MATIC), a radio test site owned and operated by
military contractor Laguna Industries. In a 2003 news article, MATIC was described as a "32,000-square-mile range" intended to "test frequencies, radios and other aspects of communications networks, using the mesas and hills around Laguna Pueblo to simulate battlefield conditions for short-range radio equipment." On the afternoon of February 16, 2005, the investigating hams reached the outer perimeter of MATIC and began taking photographs of a fenced compound containing buildings, towers and antennae, but they quickly fled when they were approached by a
security guard, shouting at them to not take pictures. Three hours later, the radio broadcasts abruptly ceased, and have not been heard since. Laguna Industries also removed all references to MATIC from their official website; and tests of a vehicle-mounted
directed energy weapon (described in documents as a microwave-based "prototype engine stopper") for the
US Department of Justice in April 2009. ==See also==