Geneva Frequency Plan of 1975
||This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (December 2011)|
The Geneva Frequency Plan of 1975 (Aka "The Final Acts of the Regional Administrative LF/MF Broadcasting Conference (Regions 1 and 3) Geneva, 1975" or simply "GE75") 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 (separate agreements 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 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 it is still valid (with small modification by mutual coordination between countries) today. The ability for countries to agree subsequent amendments to the plan has given sufficient flexibility to ensure that 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 (only one or two 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. 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 medium wave (and later longwave) stations outside North and South America operate on exact multiples of 9 kHz which helps reduce heterodyne interference.
Predecessors to the GE75 Plan
- Geneva 1925 (effective 14 Nov 1926) 10 kHz spacings on MW;
- Brussels 1928 (effective 13 Jan 1929) 9 kHz spacings on MW (10 kHz above 1000 kHz);
- Prague 1929(effective 30 June 1929) "European Radio-electric Conference of Prague 1929" 9 kHz spacings on MW (10 kHz above 1400 kHz);
- Madrid/Lucerne 1932 (effective 15 Jan 1934 |pages12-13) "Lucerne Convention European Wavelength Plan" Mostly 9 kHz spacings but not harmonic multiples;
- Montreux 1939 (was to be effective 1940 but never implemented due to World War II);
- Copenhagen 1948 (effective 15 Mar 1950) "European LW/MW Conference Copenhagen 1948 (European broadcasting convention)" Mostly 9 kHz (8 kHz above 1529 kHz 7, 8 and 9 kHz on LW) spacings but not harmonic multiples—offset 1 kHz on MW and (generally) 2 kHz on LW.
- Smith, Mike. "UK Radio: A Brief History - Part 3". MDS975.
- "The Prague Broadcasting Frequency Plan". Radio Service Bulletin (United States Department of Commerce Radio Division) (146): 25. 31 May 1929.
- McCarthy, Clive (28 May 2007). "Development of the A.M. Transmitter Network, Rev 6a".
- Verdijk, Jan. "Zenderindeling volgens Kopenhagen 1948" [Transmitter Classification according to Copenhagen 1948] (in Dutch). Archived from the original on 17 November 2007.
- "Der Kopenhagener Wellenplan" [The Copenhagen Frequency Plan]. Funk-Technik (in German) (24): 604. 1948. Archived from the original on 26 July 2011.
- "Copenhagen Plan: Annexed to the European Broadcasting Convention". Copenhagen. 1948. Archived from the original on 4 April 2012.
- Brummer, Walter. "Die Lang- und Mittelwellensender in Europa, Nahost und Afrika bei der Umstellung nach dem Genfer Wellenplan am 23.11.1978 inkl. der Neukoordinierungen" [The Long- and Mediumwave Stations in Europe, Middle East and Africa in the transition to the Geneva Frequency Plan on 23.11.1978 including the New Coordinations] (in German).
- "Amendments to the GE75 plan, 2001-2011". International Telecommunication Union.
- "GE75 Agreement, Geneva 1975 (Some resources require login)". International Telecommunication Union.