Long Wave Band Information
The Longwave radio broadcasting band lies between the frequency range 148.5 - 283.5 kHz (1000 - 2000 metres). Longwave signals tend to follow the curvature of the earth, which makes them suitable for continuous, continental transmissions. Unlike short and mediumwave frequencies, longwave signals are not reflected or refracted by the ionosphere so there are fewer interference caused fadeouts. The D-layer of the ionosphere and the surface of the earth serve as a waveguide and thus reception is possible over a wide area.
The earliest radio transmitters all used this band, due in part to the difficulty in generating higher frequencies (radio alternator and spark-gap transmitters were in use) and because the propagation of radio waves at higher frequencies was poorly understood.
In Europe, North Africa and Russia (ITU Regions 1 and 3) frequencies in the band 148.5 to 283.5 are in use for domestic and international broadcasting. Carrier frequencies are multiples of 9 kHz from 153 to 279 kHz. There are a couple of exceptions being used by transmitters in Germany, which are offset by 3 kHz either side of 180 kHz and in Mongolia where 164, 209, and 227 kHz are used.
In the past transmitters operated on frequencies as high as 413 kHz although the highest frequency currently in use is 279 kHz. Some stations such as DLF (153 kHz) derive their carrier frequencies from an atomic clock and are therefore used as frequency standards.
In the Americas (ITU Region 2) there is no longwave broadcasting, although in the 1970s the frequencies of 167, 179, and 191 kHz were used for a short lived Civil Defence Network. The portion of the band from 160-190 is currently allocated to Part 15 Lowfers.
Please select a frequency from the menu on the right hand side to find more information about stations, including locations, for each frequency.
