On June 10, a listener in Danville, IL picked up 90 seconds of NHPR signal. A station’s radio wave “footprint”, or estimated range, is generally considered to extend only about as far as the eye can see from the point of the antenna, but Danville is just under a thousand miles away. It would take more than a good pair of binoculars to put Danville within range of sight; so how did this happen?
Amateur radio enthusiasts, known as “DXers”, describe what our listener caught a glimpse of as an “E-Skip”.
To understand what that is you need to head way up into the air.