The station is noted for the sound of a ticking clock in the background, with its hosts announcing the time, every minute of broadcast.

The station dates back from an era when some Cubans were too poor to own a watch or clock.

[2] At night, using a good radio, the station can be heard around the Caribbean and Southern United States.

From its inception in 1947 until the Internet era, Radio Reloj was generally available only to listeners in Cuba.

A good example of DXing of Radio Reloj was on the morning of 21 January 1999 at 1:20 a.m. (Eastern Time).