6 meters
Encyclopedia
The 6-meter band is a portion of the VHF
radio spectrum allocated to amateur radio
use. Although located in the lower portion of the VHF band, it nonetheless occasionally displays propagation
mechanisms characteristic of the HF
bands. This normally occurs close to sunspot maximum, when solar activity
increases ionization levels in the upper atmosphere. During the last sunspot peak of 2005, worldwide 6-meter propagation occurred making 6-meter communications as good as or in some instances and locations, better than HF frequencies. The prevalence of HF characteristics on this VHF band has inspired amateur operators to dub it the "magic band".
In the northern hemisphere, activity peaks from May through early August, when regular sporadic E propagation
enables long-distance
contacts spanning up to 2500 kilometres (1,553.4 mi) for single-hop propagation. Multiple-hop sporadic E propagation allows intercontinental communications at distances of up to 10000 kilometres (6,213.7 mi). In the southern hemisphere, sporadic E propagation is most common from November through early February.
are not universal worldwide. In the United States and Canada, the band ranges from 50 MHz
to 54 MHz. In some other countries, the band is restricted to military communications
. Further, in some nations, the frequency range is used for television transmissions, although most countries have assigned those television channels to higher frequencies (see channel 1).
Although the International Telecommunication Union
does not allocate 6-meter frequencies to amateurs in Europe, the decline of VHF television
broadcasts and commercial pressure on the lower VHF spectrum has allowed most European countries to provide a 6-meter amateur allocation.
In the United Kingdom
, it is legal to use the 6-meter band between frequencies 50 MHz to 52 MHz, with some limitations at some frequencies. In the UK, 50 MHz to 51 MHz is primary usage and the rest is secondary with power limitations. A detailed bandplan can be obtained from the Radio Society of Great Britain
(RSGB) website
Many organizations promote regular competitions in this frequency to promote its use and to familiarize 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-meter band operator groups. These people monitor the status of the band between different paths and promote 6-meter band operations.
For a full list of countries using 6-meters refer to the bandplan of the IARU
http://www.iaru.org/bandplans.html.
s that include the 6-meter band has increased greatly. Many commercial HF transceivers now include the 6-meter band, as do some handheld VHF/UHF
transceivers. There are also a number of stand-alone 6-meter band transceivers, although commercial production of these has been relatively rare in recent years. Despite support in more available radios, however, the 6-meter band does not share the popularity of amateur radio's 2-meter 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 the 6-meter band's greater susceptibility to local electrical interference.
As transceivers have become more available for the 6-meter band, it has quickly gained popularity. In many countries, including the United States
, access is granted to entry-level license holders. Those without access to international HF 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 it, even when they gain access to the HF frequencies after upgrading their licenses.
In North America, especially in the United States and Canada, the 6-meter band may be used by licensed amateurs for the safe operation of radio-controlled (RC) aircraft
and other types of RC
hobby miniatures. By general agreement among the amateur radio community, 200 kHz of the 6-meter band is reserved for the telecommand
of models, by licensed amateurs using amateur frequencies. The sub-band reserved for this use is 50.79 MHz to 50.99 MHz. The upper end of the band, starting at 53.0 MHz, and going upwards in 100 kHz steps to 53.8 MHz, used to be similarly reserved for RC modelers, but with the rise of amateur repeater
stations operating above 53 MHz in the United States, and very few 53 MHz RC units in Canada, the move to the lower end of the 6-meter spectrum for radio-controlled model flying activities by Hams was undertaken in North America, starting in the early 1980s, and more-or-less completed by 1991. It is still completely legal for ground-level RC model operation (cars, boats, etc.) to be accomplished on any frequency the band, above 50.1 MHz, for suitably licensed amateur operators in the United States; however, an indiscriminate choice of frequencies for RC operations is discouraged by the amateur radio community.
Very high frequency
Very high frequency is the radio frequency range from 30 MHz to 300 MHz. Frequencies immediately below VHF are denoted High frequency , and the next higher frequencies are known as Ultra high frequency...
radio spectrum allocated to amateur radio
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
use. Although located in the lower portion of the VHF band, it nonetheless occasionally displays propagation
Radio propagation
Radio propagation is the behavior of radio waves when they are transmitted, or propagated from one point on the Earth to another, or into various parts of the atmosphere...
mechanisms characteristic of the HF
High frequency
High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency...
bands. This normally occurs close to sunspot maximum, when solar activity
Solar variation
Solar variation is the change in the amount of radiation emitted by the Sun and in its spectral distribution over years to millennia. These variations have periodic components, the main one being the approximately 11-year solar cycle . The changes also have aperiodic fluctuations...
increases ionization levels in the upper atmosphere. During the last sunspot peak of 2005, worldwide 6-meter propagation occurred making 6-meter communications as good as or in some instances and locations, better than HF frequencies. The prevalence of HF characteristics on this VHF band has inspired amateur operators to dub it the "magic band".
In the northern hemisphere, activity peaks from May through early August, when regular sporadic E propagation
Sporadic E propagation
Sporadic E or Es is an unusual form of radio propagation using characteristics of the Earth's ionosphere. Whereas most forms of skywave propagation use the normal and cyclic ionization properties of the ionosphere's F region to refract radio signals back toward the Earth's surface, sporadic E...
enables long-distance
DXing
DXing is the hobby of tuning in and identifying distant radio or television signals, or making two way radio contact with distant stations in amateur radio, citizens' band radio or other two way radio communications. Many DXers also attempt to receive written verifications of reception from the...
contacts spanning up to 2500 kilometres (1,553.4 mi) for single-hop propagation. Multiple-hop sporadic E propagation allows intercontinental communications at distances of up to 10000 kilometres (6,213.7 mi). In the southern hemisphere, sporadic E propagation is most common from November through early February.
Amateur radio
- The Radio Regulations of the International Telecommunication Union allow amateur radio operations in the frequency range from 50.000 to 54.000 MHz.
Frequency allocations
6-meter frequency allocations for amateur radioAmateur radio frequency allocations
Amateur radio frequency allocation is done by national telecommunications authorities. Globally, the International Telecommunication Union oversees how much radio spectrum is set aside for amateur radio transmissions...
are not universal worldwide. In the United States and Canada, the band ranges from 50 MHz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
to 54 MHz. In some other countries, the band is restricted to military communications
Military communications
Historically, the first military communications had the form of sending/receiving simple signals . Respectively, the first distinctive tactics of military communications were called Signals, while units specializing in those tactics received the Signal Corps name...
. Further, in some nations, the frequency range is used for television transmissions, although most countries have assigned those television channels to higher frequencies (see channel 1).
Although the International Telecommunication Union
International Telecommunication Union
The International Telecommunication Union is the specialized agency of the United Nations which is responsible for information and communication technologies...
does not allocate 6-meter frequencies to amateurs in Europe, the decline of VHF television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
broadcasts and commercial pressure on the lower VHF spectrum has allowed most European countries to provide a 6-meter amateur allocation.
In the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, it is legal to use the 6-meter band between frequencies 50 MHz to 52 MHz, with some limitations at some frequencies. In the UK, 50 MHz to 51 MHz is primary usage and the rest is secondary with power limitations. A detailed bandplan can be obtained from the Radio Society of Great Britain
Radio Society of Great Britain
First founded in 1913 as the London Wireless Club, the Radio Society of Great Britain is the United Kingdom's recognised national society for amateur radio operators. The society's patron is Prince Philip, Duke of Edinburgh and it represents the interests of the UK’s 60,000 licensed radio amateurs...
(RSGB) website
Many organizations promote regular competitions in this frequency to promote its use and to familiarize 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-meter band operator groups. These people monitor the status of the band between different paths and promote 6-meter band operations.
For a full list of countries using 6-meters refer to the bandplan of the IARU
IARU
IARU may refer to:* International Amateur Radio Union* International Alliance of Research Universities* An alternative spelling for Aaru in ancient Egyptian mythology...
http://www.iaru.org/bandplans.html.
Equipment
Over the past decade or so, the availability of transceiverTransceiver
A transceiver is a device comprising both a transmitter and a receiver which are combined and share common circuitry or a single housing. When no circuitry is common between transmit and receive functions, the device is a transmitter-receiver. The term originated in the early 1920s...
s that include the 6-meter band has increased greatly. Many commercial HF transceivers now include the 6-meter band, as do some handheld VHF/UHF
Ultra high frequency
Ultra-High Frequency designates the ITU Radio frequency range of electromagnetic waves between 300 MHz and 3 GHz , also known as the decimetre band or decimetre wave as the wavelengths range from one to ten decimetres...
transceivers. There are also a number of stand-alone 6-meter band transceivers, although commercial production of these has been relatively rare in recent years. Despite support in more available radios, however, the 6-meter band does not share the popularity of amateur radio's 2-meter 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 the 6-meter band's greater susceptibility to local electrical interference.
As transceivers have become more available for the 6-meter band, it has quickly gained popularity. In many countries, including the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, access is granted to entry-level license holders. Those without access to international HF 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 it, even when they gain access to the HF frequencies after upgrading their licenses.
Common uses
- AMAmplitude modulationAmplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
Simplex (direct, radio-to-radio communications) - FMFrequency modulationIn telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
Simplex (direct, radio-to-radio communications) - FM repeaterRepeaterA repeater is an electronic device that receives asignal and retransmits it at a higher level and/or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.-Description:...
operation - Earth-Moon-Earth BounceEME (communications)Earth-Moon-Earth, also known as moon bounce, is a radio communications technique which relies on the propagation of radio waves from an Earth-based transmitter directed via reflection from the surface of the Moon back to an Earth-based receiver....
- Sporadic E propagationSporadic E propagationSporadic E or Es is an unusual form of radio propagation using characteristics of the Earth's ionosphere. Whereas most forms of skywave propagation use the normal and cyclic ionization properties of the ionosphere's F region to refract radio signals back toward the Earth's surface, sporadic E...
- AuroraAurora (astronomy)An aurora is a natural light display in the sky particularly in the high latitude regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere...
Borealis Reflection - WSJTWSJT (Amateur radio software)WSJT is a computer program used for weak-signal radio communication between amateur radio operators. The program was initially written by Joe Taylor, K1JT, but is now open source and is developed by a small team...
Digital Modes - Packet radioPacket radioPacket radio is a form of packet switching technology used to transmit digital data via radio or wireless communications links. It uses the same concepts of data transmission via Datagram that are fundamental to communications via the Internet, as opposed to the older techniques used by dedicated...
- SSBSingle-sideband modulationSingle-sideband modulation or Single-sideband suppressed-carrier is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth....
voice operation - Morse codeMorse codeMorse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
(CWContinuous waveA continuous wave or continuous waveform is an electromagnetic wave of constant amplitude and frequency; and in mathematical analysis, of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a carrier wave is switched on and off...
) operation - DXDXingDXing is the hobby of tuning in and identifying distant radio or television signals, or making two way radio contact with distant stations in amateur radio, citizens' band radio or other two way radio communications. Many DXers also attempt to receive written verifications of reception from the...
- Radio controlRadio controlRadio control is the use of radio signals to remotely control a device. The term is used frequently to refer to the control of model vehicles from a hand-held radio transmitter...
Radio control
| Ch | Frequency |
|---|---|
| 00 | 50.80 MHz |
| 01 | 50.82 MHz |
| 02 | 50.84 MHz |
| 03 | 50.86 MHz |
| 04 | 50.88 MHz |
| 05 | 50.90 MHz |
| 06 | 50.92 MHz |
| 07 | 50.94 MHz |
| 08 | 50.96 MHz |
| 09 | 50.98 MHz |
In North America, especially in the United States and Canada, the 6-meter band may be used by licensed amateurs for the safe operation of radio-controlled (RC) aircraft
Radio-controlled aircraft
A radio-controlled aircraft is controlled remotely by a hand-held transmitter and a receiver within the craft...
and other types of RC
Radio control
Radio control is the use of radio signals to remotely control a device. The term is used frequently to refer to the control of model vehicles from a hand-held radio transmitter...
hobby miniatures. By general agreement among the amateur radio community, 200 kHz of the 6-meter band is reserved for the telecommand
Telecommand
A telecommand is a command sent to control a remote system or systems not directly connected to the place from which the telecommand is sent. The word is derived from tele = remote , and command = to entrust/order...
of models, by licensed amateurs using amateur frequencies. The sub-band reserved for this use is 50.79 MHz to 50.99 MHz. The upper end of the band, starting at 53.0 MHz, and going upwards in 100 kHz steps to 53.8 MHz, used to be similarly reserved for RC modelers, but with the rise of amateur repeater
Repeater
A repeater is an electronic device that receives asignal and retransmits it at a higher level and/or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.-Description:...
stations operating above 53 MHz in the United States, and very few 53 MHz RC units in Canada, the move to the lower end of the 6-meter spectrum for radio-controlled model flying activities by Hams was undertaken in North America, starting in the early 1980s, and more-or-less completed by 1991. It is still completely legal for ground-level RC model operation (cars, boats, etc.) to be accomplished on any frequency the band, above 50.1 MHz, for suitably licensed amateur operators in the United States; however, an indiscriminate choice of frequencies for RC operations is discouraged by the amateur radio community.
Books
- ISBN 0-9705206-3-8 SIX METERS, A GUIDE TO THE MAGIC BAND (Worldradio Books) by Ken Neubeck WB2AMU (Fourth Edition released in October 2008)
Propagation sites
- VE3EN's 6-Meter Multimedia Page
- DX-Sherlock's real-time 6m propagation maps
- DX-Sherlock's real-time VHF&up propagation ticker
- 6m News,Forums, Propagation Reports & More