4-meter band

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

As only a few countries within and outside of Europe have allocated the band for amateur radio access, the availability of dedicated commercially manufactured equipment is limited. Most radio amateurs active on the band are interested in home construction or the modification of private mobile radio (PMR) equipment. As a result, communication on the 4-metre band tends to focus on technical topics, with long 'rag chews' being the norm as long as there is some local activity.

History

Before World War II, British community radio stations had been allocated a band at 56 MHz. After the war ended, they were moved to the 5 metre band (58.5–60 MHz) instead. This only lasted until 1949, as the 5 metre band was earmarked for BBC Television broadcasts. Meanwhile, in 1948, 72–72.8 MHz was allocated to France (until 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 community radio stations 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 500 kHz 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 and 72.8 MHz:[2]

Country  Allocation    Country  Allocation    Country  Allocation   
Austria70 MHz (special licences) 
Finland70.2–70.3 MHz    Germany70.3–70.4 MHz    Ireland70.575–70.775 MHz   
The Netherlands70.3–70.4 MHz    Norway70.6–72.0 MHz    Yugoslavia72.0–72.8 MHz   

In March 1993 the European Radio Communications Office (now ECC) of the CEPT launched Phase II of a detailed spectrum investigation (DSI) covering the frequency range 29.7–960.0 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 authorised the use of the 4 metre band to community radio stations. Movement away from the old Eastern European VHF FM broadcast band and migration of commercial stations to higher frequencies in recent times allowed a slow but constant growth in the number of countries where 4 metre amateur radio 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 community radio stations with footnote 'ECA9'. This regulatory allowance has helped underpin further growth and use of the band. 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 (70MHz.org).[3]

Propagation

The 4 metre band shares many characteristics with the adjacent 6 metre band. As the band is 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 during the summer season, and tropospheric propagation is marginally more successful than on the 6 metre band, with propagation via the Aurora Borealis and meteor scatter generally highly effective.

While sporadic E permits Europe-wide communication, 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 broadcasting has lessened in recent years, it can still be a source of 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 Fiskars (SV2DCD) in Greece and Willem Badenhorst (ZS6WAB) in South Africa.[4][5]

Equipment and power

Access to the 4-metre band remains challenging due to limited availability of commercial 4-metre transceivers and radio equipment in general. A small number of transceiver models were purposely built for amateurs on this band, while converted private mobile radio equipment such as the Philips FM1000 and the Ascom SE550, is in widespread use. Some low power FM commercial equipment is available; however these units are of relatively simple specifications and 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 TS 890, 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 70 MHz 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.

Continental Europe

In 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.

DX operation across Europe and beyond

During the European summer season, the band is frequently open for DX work across the continent, with the centre of activity for long-distance voice and digital/data communication situated in the lower part of the band. The compact size of both horizontal and vertical antennas designed for the 70 MHz band is beneficial to radio amateurs who enjoy DX work but have insufficient space for larger multi-element antennas designed for lower frequencies.

DX voice traffic in SSB mode can be found around the SSB calling frequency of 70.200 MHz, whereas AM/FM contacts tend can be initiated at the 70.260 MHz AM/FM centre of activity. When the band conditions are poor or in cases where stations operator are able to transmit with modest power levels only, modern digital modes, capable of decoding transmissions down to a -12 dB s/n level, such as PSK31, Thor or Olivia, still permit reliable keyboard-to-keyboard free text communications at relatively large distances. Other more resilient digital modes capable of decoding signal down to -20 dB s/n, such as FT8, JT9 and JT65, offer reliable signal report exchanges at distances of up to several hundred or several thousand kilometres, depending on band conditions.

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 31, 2019, with the same rules as shown above.

  • Sovereign UK bases in Cyprus (70.000–70.500 MHz)
  • An automatic beacon has also been authorized in Austria, Cyprus, and Hungary
  • 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.
  • Italy (70.0875–70.1125, 70.1875–70.2125, and 70.2875–70.3125 MHz) only on temporary basis during 2007-2008-2010-2012-2014-2023(06aug-31dec).
  • Bonaire 70.000-70.500 MHz on a temporary basis from Dec 2022 until Dec 2023, might be renewed.
  • Cayman Islands 70.000-70.300 MHz on a temporary basis from 1 July 2023 until 30 June 2024

Others
  • United States has one experimental transmitter, station WE9XFT in Virginia, transmitting CW on 70.005 MHz. The beacon continues to be operated under the Experimental radio service call sign WG2XPN and is active as of March 2021.[29][30]
  • A petition was filed 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.[31] 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. YouTube (video). Archived from the original on 2021-12-21 – via ghostarchive.org.
  6. "International 70 MHz allocations". The Four Metres Website. Archived from the original on 8 June 2009. Retrieved 15 November 2009.
  7. "Frequentiebanden en technische eigenschappen toegestaan voor de verschillende klassen van radioamateurvergunningen" (PDF). bipt.be. Archived from the original (PDF) on 2016-03-08. Retrieved 2016-03-07.
  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. "Amateurfunkdienst; befristeter Zugang im Frequenzbereich 70,150 – 70,200 MHz" (PDF). bundesnetzagentur.de. Archived (PDF) from the original on 18 January 2022.
  13. "Licensing". The National Radio Amateur Association of Greece. Archived from the original on January 1, 2006. Retrieved 15 December 2015.
  14. "Ανάρτηση Πράξεων στο Διαδίκτυο | Πρόγραμμα Δι@ύγεια -".
  15. "Radio Amateur Technical Licence Conditions". Amateur Station License Guidelines. ComReg. Reference Number 09/45 R4. Retrieved 23 April 2018.
  16. "National Radio Frequency Plan".
  17. "Monaco gets 70 MHz allocation". The Southgate Amateur Radio Club. March 2006. Archived from the original on 15 April 2013. Retrieved 15 November 2009.
  18. "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.
  19. "Forskrift om radioamatørlisens". The Norwegian Law Gazette. 2019-05-03. Retrieved 2021-10-06.
  20. "International 70 MHz allocations". 70mhz.org. 2017-07-13. Retrieved 2018-04-22.
  21. "Faixa dos 70 MHz". ANACOM. 4 June 2007. Archived from the original on 22 October 2007. Retrieved 15 November 2009.
  22. "Serbia gets on 4m". September 2020.
  23. "VYHLÁŠKA Úradu pre reguláciu elektronických komunikácií a poštových služieb z 22. augusta 2022, ktorou sa ustanovujú prevádzkové podmienky pre amatérske stanice" (PDF). Zbierka zákonov Slovenskej republiky. 1 Sep 2022. Retrieved 15 December 2022.
  24. "70 MHz Band Plan for South Africa". The South African Radio League. 2017. Archived from the original on 28 April 2010. Retrieved 24 October 2021.
  25. "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
  26. "Libéralisation de la bande 4m en Suisse dès le 1er janvier 2023". USKA. December 2022.
  27. "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.
  28. "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.
  29. "WG2XPN Callsign Page". QRZ Callsign Database.
  30. "OET Experimental Licensing System Generic Search". apps.fcc.gov.
  31. "FCC petition for 4-metre band". QRZ.com. January 2010. Retrieved 27 January 2010.
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