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The 60 meter band or 5 MHz band is a relatively new amateur radio allocation, first introduced in 2002, that was originally only available in a few countries, such as the United States, United Kingdom, Norway, Finland, Denmark, Ireland and Iceland. Over a number of years however, an increasing proportion of countries' telecommunications administrations—together with their government and military users—have permitted Amateur Radio operation in the 5 MHz area on a short or longer term basis, ranging from discrete channels to a frequency band allocation. At the closing meeting of the 2015 ITU World Radiocommunications Conference (WRC 15) on 27 November 2015, amongst the Final Acts signed into the International Radio Regulations was one approving A Worldwide Frequency Allocation of 5351.5–5366.5 kHz to the Amateur Service on a secondary basis. The ITU's allocation limits amateur stations to 15 Watts effective isotropic radiated power (EIRP); however, some locations will be permitted up to 25 W EIRP.〔〔 The allocation will not come into effect until January 1, 2017.〔 Amateur stations will not be able to use this allocation until their national administration implements it. Prior to World Radiocommunication Conference 2015 (WRC-15), all 5 MHz Amateur allocations made by individual administrations were in accordance with (Article 4.4 ) of the ITU Radio Regulations, which requires non-interference with other radio services. Where two-way amateur radio communication is authorized on 60 m, it has generally been within the frequency range 5250–5450 kHz, but the whole of this range is not necessarily available and allocations vary significantly from country-to-country. This has been particularly true in latter years since the award at WRC-12 of the range 5250–5275 kHz to the Radiolocation Service, thus effectively reducing the former frequency range down to 5275–5450 kHz. In a number of countries the allocation is channelized at present, whereas others have block or band allocations. Voice operation is generally in upper sideband (USB) mode to facilitate inter-communication by non-amateur service users if necessary. In the United States and its Dependencies it is mandatory. Where channelization is used, the USB suppressed carrier frequency (a.k.a. 'dial' frequency) is normally 1.5 kHz below the quoted channel frequency. For example, 5403.5 kHz is the 'dial' frequency for the channel centred on 5405 kHz. Amateur equipment made in Japan and surrounding countries often did not support this allocation, since it is not currently available in those countries. However it is usually possible to modify equipment to work correctly on these frequencies within the terms of the individual's licensing conditions. More recently, commercial amateur radio equipment manufactured in Asia has begun to include provision for 60m/5 MHz operation. == International regulatory status == The amateur radio service is unusual in the fact that it is regulated by international treaty. Worldwide amateur allocations are determined by the International Telecommunication Union〔http://www.itu.int/en/Pages/default.aspx〕 (ITU), which allocates global radio spectrum and satellite orbits,〔http://www.itu.int/ITU-R/index.asp?category=information&link=rhome&lang=en〕 develops the technical standards that ensure networks and technologies seamlessly interconnect and strive to improve access to ICTs to underserved communities worldwide. This is done through successive World Radiocommunication Conferences (WRCs) which take place approximately every 3 – 5 years, when telecommunications administrations and organisations from all around the globe meet to make decisions on these elements. At the conclusion of the ITU 2012 World Radiocommunication Conference (WRC-12) on Friday 17 February 2012, Resolution COM6/12 was ratified as being placed on the Agenda for the next WRC in 2015 (WRC-15). This resolution invites WRC-15 to consider "The possibility of making an allocation of an appropriate amount of spectrum, not necessarily contiguous, to the amateur service on a secondary basis within the band 5250-5450 kHz" The official ITU text is as follows :-
Following the decision at WRC-12 to implement a Radiolocation allocation from 5250 to 5275 kHz, the candidate band for an amateur allocation at WRC-15 subsequently became truncated to the 5275 to 5450 kHz sector. On September 11, 2014, the National Telecommunications Agency of Brazil (Anatel) announced its intention to propose an amateur service allocation from 5275 to 5450 kHz in the 60m band at the next meeting of CITEL (Inter-American Telecommunication Commission).〔http://www.southgatearc.org/news/2014/september/brazil_proposes_5275_to_5450_khz.htm〕 At the (CITEL ) Regional Conference held in Mérida City, Mexico in October 2014, the conference recognised an IAP ( Inter-American Proposal ) for a Secondary Amateur Allocation from 5275 to 5450 kHz. This was proposed by Brazil, together with Argentina, Uruguay, El Salvador, Dominican Republic and Nicaragua, making up the required six administrations. Following the proposal a footnote stressed that "''National administrations can adopt additional constrains to provide further compatibility with existed services''". The final meeting of the CEPT (Conférence Européenne des Postes et Télécommunications) Conference Preparatory Group took place in Bergen, Norway during the week 14–18 September 2015 at which was adopted the final European Common Proposal for WRC-15 Agenda Item 1.4 - the adoption of a European Common Proposal for an allocation of 100 kHz between 5350 – 5450 kHz for the Amateur Service.〔http://www.cept.org/ecc/groups/ecc/cpg/page/8th-cpg-meeting-took-place-in-bergen,-norway〕 The ITU 2015 World Radiocommunication Conference (WRC-15) took place in Geneva, Switzerland from 2 until 27 November 2015, where Agenda Item 1.4 went through a significant amount of discussion and debate until a consensus was eventually reached, whereby at the Concluding Meeting of WRC-15 on 27 November 2015 a Final Act was signed, approving a secondary amateur allocation of 5351.5–5366.5 kHz.〔〔 Most stations will be limited to 15 Watts EIRP, with the exception of Mexico, who are allowed 20W EIRP and Central & South America, plus most of the Caribbean areas who are permitted 25W EIRP.〔〔 The allocation will go into effect from January 1, 2017.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「60-meter band」の詳細全文を読む スポンサード リンク
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