Listening to shortwave broadcast stations for news and information programming is common, but for many shortwave listeners (abbreviated as "SWLs"), the goal is to receive as many stations from as many countries as possible, also known as DXing. "DXers" routinely test the limits of their antenna systems, radios and radio propagation knowledge. Specialized interests of shortwave listeners may include listening for shortwave utility, or "ute", transmissions such as shipping, sailing, naval, aviation, or military signals, listening for intelligence signals (numbers stations), or tuning in amateur radio stations.[1]
Listeners often obtain QSL cards from ham operators, broadcasters or utility stations as trophies of the hobby. Traditionally, listeners would send letters to the station with reception reports and requests for schedules. Many stations now accept E-mails or provide reception report forms on their Web sites. Reception reports give valuable information about propagation and interference to a station's engineers.[1]