Geneva Frequency Plan of 1975

{{Short description|International agreement about radio broadcast frequencies}}

[[File:International Telecommunication Union regions with dividing lines.svg|thumb|300px|ITU's Regions 1 and 3 includes Europe, Africa, and Asia

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The Final Acts of the Regional Administrative LF/MF Broadcasting Conference (Regions 1 and 3) Geneva, 1975 is the internationally agreed frequency plan which was drawn up to implement the provisions of the Final Acts of the Regional Administrative LF/MF Broadcasting Conference (Regions 1 and 3) held in Geneva, Switzerland, in 1975. It covers radio broadcasting in the long- and medium-wave bands outside the Americas (a separate agreement being in place for North and South America).

The plan was drawn up under the auspices of the World Administrative Radio Conference (WARC) of the International Telecommunication Union (ITU) with the assistance of the European Broadcasting Union (EBU/UER).

The Geneva plan replaced the 1948 Copenhagen plan. It became necessary because of the large number of broadcasting stations in these frequency ranges leading to ever more mutual interference (many countries had refused to ratify the Copenhagen plan{{cite web |url=http://www.offshoreradiomuseum.co.uk/page489.html |title=Government regulations and state monopolies |work=Offshore Radio Museum |access-date=1 January 2017}} and compliance was patchy even among those which had). The Geneva plan entered into force on 23 November 1978 and although its intended lifespan was only until 1989,{{cite news |journal=Wireless World |date=January 1976 |page=42 |title=New medium- and long-wave broadcasting plan |url=http://www.americanradiohistory.com/Archive-Wireless-World/70s/Wireless-World-1976-01.pdf#page=44}} it is still valid (with small modification by mutual coordination between countries) today, and compliance has been far more widespread.

Most existing European radio stations were required to change their broadcasting frequencies following implementation of the plan. In most cases the changes were slight (less than five kilohertz) but were more drastic in some cases, particularly in the United Kingdom, where all BBC national stations moved to a new wavelength or band.{{cite web |url=http://www.mds975.co.uk/Content/ukradio3.html |title=UK Radio: A Brief History – Part 3 |last=Smith |first=Mike |work=MDS975 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20161106180246/http://www.mds975.co.uk/Content/ukradio3.html |archive-date=6 November 2016 }} However the increased number of radio services and reduction (in most cases) of interference to radio signals (particularly at nighttime) was considered by most broadcasters to be worth the initial inconvenience.

As a result of the plan most mediumwave (and later longwave) stations outside North and South America operate on exact multiples of 9 kHz; the sum of all digits of the frequency will be 9 or a multiple of 9 (see 9#Mathematics).

Geneva Frequency Plan of 1975

Predecessors to the GE75 Plan

See also

References

External links