6 meters

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6 meters is the name given to a popular amateur radio band. Its spectrum is in the lower part of the VHF band, but still occasionally displays some propagation mechanisms of the lower High Frequency bands. This normally occurs close to sunspot maximum when solar activity increases ionization levels in the upper atmosphere. The mix of VHF and HF characteristics has led to 6 meters being dubbed the "magic band."

In the northern hemisphere, six meter activity is very popular from May through early August when sporadic Es propagation becomes a regular occurrence enabling 'DX' contacts over distances up to 2,500 km for single hop propagation. Multiple hop sporadic E propagation allows inter-continental communications at distances up to 10,000 km. In the southern hemisphere, sporadic E propagation is most common from November through early February.

The frequency allocations for 6 meters are not universal worldwide. In the United States, and Canada, it ranges from 50 to 54 MHz. But, in other countries, it is illegal to use due to local military communications. Further, in some nations, the frequency range occupied by the six-meter amateur radio band is used for television transmissions, although most countries have moved the channels to higher frequencies (see channel 1).

Over the past decade or so, the availability of transceivers that include the six-meter band has increased greatly. Most modern HF amateur radios now include the six-meter band, as do some handheld VHF/UHF transceivers. There have existed and do exist a number of stand-alone 6 Meter transceivers, although these have been relatively rare in recent years. Despite this, 6 meters does not share the popularity of amateur radio's 2 meters band. This is due, in large part, to the larger size of 6 meter antennas, power limitations in some countries outside the United States, and 6 meter's greater susceptibility to local electrical interference.

As transceivers have become more available for the magic band, 6 meters has quickly gained popularity. In many countries, including the United States, access to 6 meters is granted to entry-level license holders. Those without access to the international "HF" or shortwave frequencies often gain their first taste of true long-distance communications on the 6 meter band. Many of these operators develop a real affection for the challenge of the band, and often continue to devote much time to 6 meters, even when they gain access to the HF frequencies after upgrading their licences.

Although the International Telecommunications Union does not allocate 6 meter frequencies to amateurs in Europe, due to the decline of VHF television broadcasts and commercial pressure on the lower VHF spectrum, most European countries have a 6 meter amateur allocation. A list showing the status of amateur radio allocation in the countries of ITU Region 1.

In United Kingdom, it is legal to use 6 meters between frequencies 50 to 52 MHz, with some limitations at some frequencies. In UK, 50 to 51 MHz is primary usage and the rest is secondary with power limitations. The detailed band plan for UK can be obtained from RSGB Band plan documentation (PDF).

Many organizations promote regular competitions in this frequency to promote its use and to familiarise operators to its quirks. For example RSGB VHF Contest Committee has a large number of contests on 6 meters every year.

Because of its peculiarity, there are a number of 6 meters operator groups. These people monitor the status of the band between different paths and promote 6 meter operations.

Contents

[edit] Organizations

[edit] Books

SIX METERS, A GUIDE TO THE MAGIC BAND (Worldradio Books) by Ken Neubeck WB2AMU

[edit] Band plans

[edit] IARU Region 1 50 MHz Band Plan

(with the UKSMG's recommended change to the adoption of the term
"inter-regional" rather than "inter-continental")

50.000 - 50.100    CW only    50.020 - 50.080     Beacons
        50.090     CW calling frequency
50.100 - 50.500    SSB and CW only    50.100 - 50.130     DX window
        50.110     Inter-Region calling frequency
        50.150     SSB centre of activity
        50.185     Cross-band activity centre
        50.200     MS reference frequency (CW and SSB)
50.500 - 51.000    All modes    50.500 - 50.700     Digital communications
        50.510     SSTV
        50.550     Fax
        50.600     RTTY
        50.710 - 50.910     FM repeater outputs (UK)
51.000 - 51.410    All modes    51.210     Emergency communications priority
        51.210 - 51.410     FM repeater inputs (UK)
51.410 - 51.830    All modes    51.430 - 51.590     FM, 20 kHz channel spacing
        51.510     FM calling
51.830 - 52.000    All modes    51.940 - 52.000     Emergency communications priority

(Source: VOLUNTARY OPERATING CODE OF PRACTICE for 6m operators UKSMG 16 February 2003)

[edit] US/North American 6m Band Plan

50.0-50.1 CW, beacons
50.060-50.080 beacon subband (US only)
50.1-50.3 SSB, CW
50.1-50.125 DX window; 50.125 calling freq
50.125 US continental SSB calling
50.3-50.6 All modes (50.29 PSK31)
50.4 AM calling
50.6-50.8 various modes communications
50.8-50.98 Radio remote control (Ten 20 kHz channels)
51.0-51.1 Pacific DX window
51.1-54.0 Repeaters/various plans (-1 MHz and -1.7 MHz most popular)
52.525 Primary FM simplex
53.1-53.8/100 kHz spaced Old radio remote control, NO LONGER accepted

by the AMA, due to increasing use by amateur radio repeater stations.

(Source: Academy of Model Aeronautics, Western Washington Amateur Radio Association, ARRL ARRL Band Plans)

[edit] IARU Region 3 Band Plan

The Band Plan for IARU Region 3 may be found in their Band Plan Document

[edit] Common uses of 6 meters

[edit] Links to 6m propagation sites

Very high frequency (VHF) and ultra high frequency (UHF) amateur radio bands
VHF UHF
6 m 4 m 2 m 1.25 m 70 cm 33 cm 23 cm 13 cm
50 MHz 70 MHz 144 MHz 219–220 MHz 420 MHz 902 MHz 1.24 GHz 2.3–2.31 GHz
54 MHz 70.5 MHz 148 MHz 222–225 MHz 450 MHz 928 MHz 1.3 GHz 2.39–2.45 GHz


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