What Does DX Mean in Radio?by Noel Shankel
Heinrich Hertz discovered radio waves in 1887, and since then the radio has become a common item. Sometimes people pick up non-local signals from great distances. While this might seem odd, or even annoying, it is far from unusual.
Whenever a radio picks up a signal from a very long distance, it is referred to as a DX, or distant reception. "DXing" is the act of trying to pick up distant radio signals.
The Federal Communications Commission (FCC) allocated the band for FM broadcasting in 1940 and soon discovered that distant FM radio signals, as far as 1,400 miles away, could interfere with other radio broadcasts. In 1942, FM Magazine published the first known report of a FM signal traveling well outside of its broadcasting area. The signal, which originated in Illinois, was heard in Monterrey, Mexico, more than 1,000 miles away.
Those who are interested in picking up distant radio signals can achieve this by simply scanning their radio dials. As soon as you hear a radio signal that isn't within your local FM broadcasting area, you are officially DXing.