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4-metre band

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The 4-metre (70 MHz) band is an amateur radio band within the lower part of the very high frequency (VHF) band.

The 4-metre band is unusual; very few countries outside of Europe have allocated amateur access. Hence, very little dedicated commercial amateur equipment is available, and most amateurs active on the band are interested in home construction or modification of private mobile radio (PMR) equipment. As a result, there is a lot of camaraderie on the band, and long 'ragchews' are the norm, as long as there is some local activity.

History

Before World War II, British radio amateurs had been allocated a band at 56 MHz. After the war ended, they were moved the 5-metre band (58.5–60 MHz) instead. This only lasted until 1949, as by then the 5-metre band had been earmarked for BBC Television broadcasts. Meanwhile, in 1948, 72-72.8 MHz was allocated to France (till 1961).[1]

In 1956, after several years of intense lobbying by the Radio Society of Great Britain (RSGB), the 4-metre band was allocated to British radio amateurs as a replacement for the old 5-metre band allocation. For several years the 4-metre band allocation was only 200 kHz wide, from 70.2–70.4 MHz; it was later extended to 70.025–70.7 MHz. The band limits were subsequently moved to today's allocation of 70.0–70.5 MHz.

On the occasion of the International Geophysical Year 1957-1958, the following countries have been allocated frequencies between 70-72.8 MHz. Ireland: 70.575-70.775 MHz, Finland: 70.2-70.3 MHz, Germany: 70.3-70.4 MHz, The Netherlands: 70.3-70.4 MHz, Norway: 70.6-72.0 MHz, Yugoslavia: 72.0-72.8 MHz, and Austria: 70 MHz special licences.[2]

In March 1993 the European Radiocommunications Office (now ECC) of the CEPT launched Phase II of a detailed spectrum investigation (DSI) covering the frequency range 29.7-960 MHz. The results were presented in March 1995. Regarding the Amateur Radio Service the DSI management team recommended (among other things) that 70 MHz be considered as an amateur band.

Allocations

A chart showing how television channel frequencies in various countries relate to the 4-metre amateur band.

In addition to the traditional users (United Kingdom, Gibraltar and the British Military Bases in Cyprus), an increasing number of countries in Europe and Africa have also allocated the 4-metre band to radio amateurs as a result of the decline in VHF television broadcasts on the 4-metre band. Movement away from the old Eastern European VHF FM broadcast band and migration of commercial stations to higher frequencies have led to slow but steady growth in the number of countries where 4-metre operation is permitted.

Whilst not formally allocated at an ITU or Regional level, in Europe CEPT now recognises the increased access to 70 MHz by radio amateurs with footnote 'ECA9' which has helped underpin further growth. In July 2015 CEPT updated this footnote to fully recognise it as a formal secondary allocation:

"ECA9: CEPT administrations may authorise all or parts of the band 69.9-70.5 MHz to the amateur service on a secondary basis."

In practice this ranges from 70–70.5 MHz in the United Kingdom, with other countries generally having a smaller allocation within this window. In most countries the maximum power permitted on the band is lower than in other allocations to minimise the possibility of interference with non-amateur services, especially in neighbouring countries. A table with national and regional allocations is published and regularly updated on the Four Metres Website.[3]

Propagation

The 4-metre band shares many characteristics with the adjacent 6-metre band. However, as it is somewhat higher in frequency it does not display the same propagation mechanisms via the F2 ionospheric layer normally seen at HF which occasionally appear in 6 metres, leastwise not at temperate latitudes. However, sporadic E is common on the band in summer, tropospheric propagation is marginally more successful than on the 6-metre band, and propagation via the Aurora Borealis and meteor scatter is highly effective.

While sporadic E permits Europe wide communication, it can be a mixed blessing as the band is still used for wide bandwidth, high power FM broadcasting on the OIRT FM band in a declining number of Eastern European countries. Although this has lessened in recent years, it can still cause considerable interference to both local and long distance (DX) operation.

The first ever transequatorial propagation (TEP) contact on 70 MHz took place on 28 March 2011 between Leonidas Fiskas, SV2DCD, in Greece and Willem Badenhorst, ZS6WAB, in South Africa.[4][5]

Equipment and power

Access to the 4-metre band has always been limited by access to suitable 4-metre transceivers. A limited number of transceivers were purposely built for amateurs on this band while converted private mobile radio equipment is in widespread use e.g. Phillips FM1000 and the Ascom SE550. Some low power FM commercial equipment is available for the band although it is of relatively simple specifications as generally suitable for communication of up to around 50 kilometres (31 mi) or so with simple antennas.

In the sporadic E seasons, communication around Europe is possible with such equipment. Currently, the only Japanese-made, "mass-market" amateur radio transceivers to cover the 4-metre band as standard are the Kenwood TS890, Icom IC-7100 and IC-7300 (UK models), previously there was the UK specification Yaesu FT-847 with 4 m which was discontinued in 2005. As a result, many 4-metre users gain access to the band by using converted "Low band" VHF ex-PMR (private mobile radio) transceivers but invariably these only have either AM or FM and those users who prefer to have a multi-mode capability but can't afford a secondhand Yaesu FT-847, normally use transverters, either purposely built home builds or sometimes even converted 6-metre or 2-metre versions.

In recent years there have been extensive imports of Chinese PMR transceivers such as the Wouxun KG-699E 4 m (66–88 MHz) and KG-UVD1P1LV dual band (TX / RX 66–88 MHz / 136–174 MHz) handheld transceiver to Western countries, mainly so far in the UK and mainland Europe. Qixiang Electronics, the makers of the AnyTone and MyDel transceivers, have exported the AnyTone 5189 PMR 4 m mobile, and the AnyTone 3308 handheld (66–88 MHz) transceivers from China to the UK and to Europe. Both transceivers have been selling extensively well in the UK and in Europe.

Circa 2014 a mono-band multi-mode 70 MHz SSB / CW transceiver was released by Noble Radio. As of October 2014, their 70 MHz transceiver is worldwide the only one available.

Most modern radios support the 4-meter band (software-defined radios – SDRs and others). Examples are the Flex Radio Systems 6000 series, ICOM IC-7300, Yaesu FT-DX101d, and Kenwood TS-890S.

Activity

United Kingdom

In the UK the band has a mix of AM, FM and DX activity, assisted by the recent support for 70MHz in newer amateur radio equipment. In the UK, the band is also used for emergency communications, Internet Radio Linking Project links (IRLP), data links and low powered remote control.

Ireland

There is considerable AM activity in the Dublin area. As band occupancy is relatively low, FM operation tends to take place on the 70.450 MHz calling frequency, and AM operation on the 70.260 MHz calling frequency.[citation needed]

Continental Europe

In continental Europe the band is still primarily used for more serious DX operation. Cross-band working between the 6-metre band or the 10-metre band is common to make contacts countries where the band is not allocated.[citation needed]

Countries in which operation is permitted

Red regions designate areas with known allocations. Blue regions designate areas with experimental allocations.

Countries with a known band allocation:[6]

Countries with past or current experimental operation

In "experimental" countries, authorities authorized amateur radio experiments on the band for a limited period of time.

  • Germany 2007-2010 (69.950 MHz center frequency) under a special ("DI2xx") license.

For class "A" operators in 2014, 70.000-70.030 MHz, and in 2015, 2017, & 2018, 70.150-70.180 MHz were allocated under specific restrictions (25 W ERP, Horiz. polarisation, 12 kHz maximum bandwidth, no portable operation, non interference basis, all transmissions to be logged with frequency, antenna direction, date/time, call signs) for four months, Starting May 2 and ending at the end of August each year (effectively for the sporadic-E season).

On December 19, 2018 BNetzA (the German regulator) published announcement 414/2018 issuing immediate access to 70.150-70.200 MHz for German class "A" (full) licensees up until December 31st, 2019 with the same rules as shown above.

  • Israel 70.000-70.500 MHz Starting in April 2018, Israeli amateurs may apply for an experimental permit granting access to 4 meters.
  • North Macedonia 70.000 MHz, 70.075 MHz, 70.125 MHz and 70.275 MHz Starting in May 2019, N. Macedonia amateurs may apply for a one-year experimental permit granting access to 4 meters.

Others

  • Glen Zook, K9STH, the head moderator of QRZ.com and a longtime magazine writer on VHF related topics, filed a petition with the U.S. Federal Communications Commission on 27 January 2010 to create a new U.S. 4-meter amateur radio allocation at 70 MHz to parallel those in Europe and other parts of the world.[26] This petition was subsequently rejected by the FCC.

Common uses of the 4-metre band

References

  1. ^ "Historique des bandes de ffėquence". oernst.f5lvg.free.fr.
  2. ^ "International frequency allocations in the IGY-year". 70MHz.org.
  3. ^ "International 70 MHz allocations". 70MHz.org.
  4. ^ "World's first TEP QSO on 70 MHz". 70MHz.org. 31 March 2011.
  5. ^ ZS6WAB (video).
  6. ^ "International 70 MHz allocations". The Four Metres Website. Archived from the original on 8 June 2009. Retrieved 15 November 2009.
  7. ^ http://www.bipt.be/public/files/nl/21220/+FRERAM-16%20VN.pdf
  8. ^ retsinformation.dk, BEK nr 829 af 09/08/2019: Bekendtgørelse om anvendelse af radiofrekvenser uden tilladelse samt om amatørradioprøver og kaldesignaler m.v., backup
  9. ^ oz1ln.dk: 70 MHz Repeaters in Denmark
  10. ^ "Amatöörraadioside raadiosagedusalad, saateliigid, kiirgusklassid ja suurimad saatevõimsused" (PDF). Riigi Teataja (in Estonian). 28 March 2005.
  11. ^ "Radioamatöörimääräys" (PDF). The Finnish Communications Regulatory Authority (FICORA). 4 November 2009. pp. 11, 13. Retrieved 15 November 2009.
  12. ^ "Licensing". The National Radio Amateur Association of Greece. Archived from the original on January 1, 2006. Retrieved 15 December 2015.
  13. ^ https://diavgeia.gov.gr/decision/view/%CE%A9%CE%A9%CE%93%CE%A31-%CE%A9%CE%9A%CE%9D
  14. ^ "Radio Amateur Technical Licence Conditions". Amateur Station License Guidelines. ComReg. Reference Number 09/45 R4. Retrieved 23 April 2018.
  15. ^ "National Radio Frequency Plan".
  16. ^ "Monaco gets 70 MHz allocation". The Southgate Amateur Radio Club. March 2006. Archived from the original on 15 April 2013. Retrieved 15 November 2009.
  17. ^ "Regeling van de Minister van Economische Zaken, Landbouw en Innovatie van 20 december 2011, nr. AT-EL&I/6621235, tot wijziging van de Regeling gebruik van frequentieruimte zonder vergunning 2008 in verband met de implementatie van twee besluiten van de Commissie van de Europese Gemeenschappen en het vergunningvrij maken van het gebruik van grond- en muur penetrerende radar". overheid.nl. 2011-12-30. Retrieved 2012-03-01.
  18. ^ "Forskrift om radioamatørlisens". The Norwegian Law Gazette. 6 November 2009. Retrieved 15 November 2009.
  19. ^ "International 70 MHz allocations". 70mhz.org. 2017-07-13. Retrieved 2018-04-22.
  20. ^ "Faixa dos 70 MHz". ANACOM. 4 June 2007. Archived from the original on 22 October 2007. Retrieved 15 November 2009.
  21. ^ "Slovak Radio Amateurs gain access to 70 MHz band". The Southgate Amateur Radio Club. May 2009. Archived from the original on 15 April 2013. Retrieved 15 November 2009.
  22. ^ "70 MHz Band Plan for South Africa". The South African Radio League. 26 August 2003. Archived from the original on 28 April 2010. Retrieved 15 November 2009.
  23. ^ "Telecommunications Act of 1996, as amended" (PDF). The South African Radio League. February 2005. p. 23. Archived from the original (PDF) on 2016-01-12. Retrieved 15 November 2009. 70.000-70.300 Secondary
  24. ^ "United Kingdom Table of Radio Frequency Allocations". Ofcom. Retrieved 15 November 2009. The band 70.0-70.5 MHz is allocated to the Amateur service.
  25. ^ "UK Interface Requirement 2028 - Amateur Radio Licences – Foundation, Intermediate, and Full" (PDF). Ofcom. January 2007. p. 12. Archived from the original (PDF) on 31 March 2010. Retrieved 15 November 2009.
  26. ^ "FCC petition for 4-metre band". QRZ.com. January 2010. Retrieved 27 January 2010.
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