MONITORING RESEARCH - 13 MHZ - THE FORGOTTEN BAND!
Many newcomers to propagation research appear to be reluctant to demonstrate a continuing interest in orderly investigation of the "Forgotten Band", known as the "22 Metre Band", which is allocated exclusively worldwide to the HF Broadcasting Service, extending from 13600 to 13800.
The spectrum extending between 13700 and 13600 and 13800 to 13870 is also used by the Broadcasting Service, shared with Fixed and Mobile Services on a "non-interference" basis.
The 22 mb was introduced on an experimental basis in the late 1980s, as an outcome of a World Administrative Radio Conference , and authorized officially in 1990. Even before 1970, some regional broadcasters were operating there, competing with the many utility and Point-to-Point broadcasters already using that spectrum.
The band was introduced primarily for daytime transmissions in Europe, for paths supported by multi-hop daylight E-mode propagation, covering the range 1000 km out to about 4000 km. During darkness hours, the useful range was predicted to extend from about 3000 km to half-way around the world.
Since its introduction, many international broadcasters have moved in, as well as broadcasters targeting domestic audiences.
Now, the band is very lively for the full 24 hours, behaving both as a darkness and daylight band, similar to the nearby 14 MHz Amateur Service Band.
Study of this band will provide useful scope for observation, analysis and documentation of long-distance propagation characteristics, in support of the growing body of technical knowledge about HF transmission.
This is a summary of observed activity in this band, as observed here in Melbourne across the time span 1800 to 1830 on April 6, 2015.
13580 BANGLADESH English
13640 INDIA Arabic
13650 KUWAIT R.Kuwait, Arabic
13660 ENGLAND BBC-Woofferton English
13685 IRAN Swahili to 1820*
13695 INDIA English
13700 CHINA CRI-Urumqi Chaozhou
13740 FRANCE RFI-Issoudun French
13760 CHINA CRI-Kashi English
13765 VATICAN VR-SMG English
13820 FRANCE R. Algeria, Issoudun Arabic
Interesting article Bob and thanks for sharing!
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