Shortwave bands are frequency allocations for use within the high frequency radio spectrum. They are the primary medium for applications such as marine communication, international broadcasting, and worldwide amateur radio activity because they take advantage of ionospheric skip propagation to send data around the world. The bands are conventionally stated in wavelength as measured by meters. Many bands, most notably the VHF 6 meters band, are notable for their behavior that depends on the season and the level of solar activity. High frequency (HF) radio frequencies are between 3 and 30 MHz. ... Amateur radio - Wikipedia, the free encyclopedia /**/ @import /skins-1. ... The wavelength is the distance between repeating units of a wave pattern. ... Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m). ... // Summary 6 Meters is a popular ham radio band. ...

The "11-meter" (27MHz) band is the most significant location allocated by most countries for Citizen's Band service, though due to the band's propagation characteristics, which allow long-distance interference with local signals, most land mobile radio activity has moved to VHF or UHF. A typical mobile citizens band radio Citizens band radio (CB) is, in the United States, a system of short distance radio communication between individuals on a selection of 40 channels within the single 27 MHz (11 meter) band. ... Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m). ... This article is about the radio frequency. ...

International Broadcasting Bands

The band frequencies below are derived from multiple sources, and your radio might have different numbers. Most international broadcasters use amplitude modulation with a stepping of 5 KHz between channels; a few use single sideband modulation. Your radio may have different definitions of the bands. Amplitude modulation (AM) is a form of modulation in which the amplitude of a carrier wave is varied in direct proportion to that of a modulating signal. ... Single-sideband modulation (SSB) is a refinement of the technique of amplitude modulation designed to be more efficient in its use of electrical power and bandwidth. ...

• 11 meters - 25.67-26.10 MHz - Very little broadcasting activity in this band. Day reception tends to be poor, night reception nonexistent. This band could be used for daytime 'single hop' regional coverage, but very few broadcast transmitters and anteannas function in this band. Not to be confused with the Citizen's Band 11-meter allocation, which in most countries runs from 26.965 MHz to 27.405 MHz.
• 13 meters - 21.45-21.50 MHz - Somewhat shaky day reception, very little night. Similar case to 11 metres, but long distance daytime broadcasting keeps this band humming in the Asia-Pacific region.
• 15 meters - 18.90-19.02 MHz - Seldom used.
• 16 meters - 17.48-17.90 MHz - Day reception good, night reception varies seasonally, with summer being the best.
• 19 meters - 15.00-15.825 MHz - Day reception good, night reception variable, best during summer. Time stations such as WWV are clustered around 15 MHz.
• 22 meters - 13.57-13.87 MHz - Similar to 19 meters; best in summer.
• 25 meters - 11.50-12.05 MHz - Generally best during summer; said to be ideal during the period before and after sunset.
• 31 meters - 9250-9995 KHz - Good year-round night band; seasonal during the day, with best reception in winter. Time stations are clustered around 10 MHz.
• 41 meters - 7100-7350 KHz - Reception varies by region -- reasonably good night reception, but few transmitters in this band are targeted to North America.
• 49 meters - 5900-6300 KHz - Good year-round night band; daytime reception is lacking.
• 60 meters - 4750-5100 KHz - Mostly used locally in tropical regions, though usable at night. Time stations are clustered around 5000 KHz.
• 75 meters - 3900-4050 KHz - Mostly used in Eastern Hemisphere, not widely received in the Americas.
• 90 meters - 3200-3400 KHz - Mostly used locally in tropical regions, with limited long-distance reception at night.
• 120 meters - 2300-2495 KHz - Mostly used locally in tropical regions, with time stations clustered around 2500 KHz. Not technically a shortwave band; resides in the upper reaches of the mediumwave band.

A typical mobile citizens band radio Citizens band radio (CB) is, in the United States, a system of short distance radio communication between individuals on a selection of 40 channels within the single 27 MHz (11 meter) band. ... WWV is the callsign of NISTs shortwave radio station located in Fort Collins, Colorado. ... Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300 kHz and 3000 kHz. ...

Amateur HF Bands

The following band allocations are the standard allocations used by the American Radio Relay League and the United States Federal Communications Commission. Consult your local regulatory body for further information; in particular, the 60-meter, 30-meter, and WARC (17, 15, and 12 meter) bands may not be available in your home country. The American Radio Relay League (ARRL) was founded in May, 1914 by Hiram Percy Maxim. ... The Federal Communications Commission (FCC) is an independent United States government agency, created, directed, and empowered by Congressional statute. ...

• 6 meters - 50-54 MHz - not actually a shortwave band but the lowest VHF band available to amateur operators, 6m is notable for its unusual propagation characteristics largely mediated by solar weather. Known as the "magic band", DXing on the band is largely done as a technical challenge. Listed here because it is commonly included on HF amateur sets.
• 10 meters - 28-29.7 MHz - Best activity is during solar maximum; during periods of moderate solar activity the best activity is found at low latitudes. Also the site of frequent bootlegging and freeband activity by operators using modified Citizen's Band equipment.
• 12 meters - 24.89-24.99 MHz - Mostly useful during daytime, but opens up for DX activity at night during solar maximum.
• 15 meters - 21-21.45 MHz - Most useful during solar maximum, and generally a daytime band.
• 17 meters - 18.068-18.168 MHz - Similar to 20m, but more sensitive to solar conditions.
• 20 meters - 14.0-14.35 MHz - Considered the most popular DX band; usually most popular during daytime. QRP operators recognize 14.060 MHz as their primary calling frequency in that band. Users of the PSK31 data mode tend to congregate around 14.071 MHz. Analog SSTV activity is centered around 14.230 MHz.
• 30 meters - 10.1-10.15 MHz - a very narrow band allowing only Morse Code and data transmissions. Maintains some independence from the solar cycle. May not be available outside the United States.
• 40 meters - 7.0-7.3 MHz - Considered the most reliable all-season DX band, and most popular at night.
• 60 meters - 5 MHz region - A relatively new allocation in most countries; the United States allocation for amateurs is channelized, with five channels that are required to operate in upper sideband mode. Amateur equipment made in Japan or China often does not support this allocation, since it is not available in those countries.
• 80 meters - 3500-4000 KHz - Best at night, with significant daytime signal absorption. Works best in winter due to atmospheric noise in summer. 80m phone operators have a reputation for rowdiness similar to CB operators.
• 160 meters - 1800-2000 KHz - Not a shortwave but a mediumwave band, and often taken up as a technical challenge in a manner similar to 6m. Most useful at night, though notoriously noisy. Also known as the "top band" and the "Gentlemen's Band", in apparent contrast to the supposedly freewheeling 80m allocation.

// Summary 6 Meters is a popular ham radio band. ... Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m). ... DX can refer to: a common telegraphic abbreviation that stood for a signal that travelled a very long distance. ... The 10 meter amateur radio band is the highest of the High Frequency or HF bands. ... Solar maximum or solar max is the period of greatest solar activity in the solar cycle of the sun. ... A typical mobile citizens band radio Citizens band radio (CB) is, in the United States, a system of short distance radio communication between individuals on a selection of 40 channels within the single 27 MHz (11 meter) band. ... DX can refer to: a common telegraphic abbreviation that stood for a signal that travelled a very long distance. ... In amateur radio, QRP operation means transmitting at reduced power levels. ... Several adjacent PSK31 signals, at least six, taken from the waterfall display of DigiPan. ... Slow-scan television (SSTV) is used by amateur radio operators, to transmit and receive static pictures in monochrome (black & white) or colour. ... Morse code is a system of representing letters, numbers and punctuation marks by means of a code signal sent intermittently. ... In radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, containing energy as a result of the modulation process. ... At just above the AM Broadcast band, 160 meters is the lowest radio frequency band alloted for use by Amateur Radio operators. ... Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300 kHz and 3000 kHz. ...

Marine and Land Mobile Allocations

The international maritime distress frequency is 2182 KHz; formerly 500 KHz was reserved for Morse Code distress signals, but this frequency allocation has been discarded in favor of systems such as GMDSS and Inmarsat. As mentioned above, most countries that have HF Citizen's Band allocations allocate 40 channels between 26.965 MHz to 27.405 MHz, in 10 KHz steps. For most of the 20th century, the radio frequency 500 kHz (known as 600 meters or 500 kc for most of the century, before kilohertz replaced kilocycle) was the international calling and distress frequency for ships on the high seas. ... The Global Maritime Distress Safety System (GMDSS) is an internationally-agreed set of safety procedures and types of equipment used to increase safety and make it easier to rescue distressed ships, boats and aircraft. ... INMARSAT, is an international telecommunications company founded in 1979, originally as an intergovernmental organisation. ...

Military Use of HF Frequency Allocation

Industrial/Scientific/Medical HF Frequency Allocation

Related Links

• Shortwave and HF
• International broadcasting

A Grundig Shortwave receiver Shortwave radio operates between the frequencies of 3,000 kHz and 30 MHz (30,000 kHz) and came to be referred to as such in the early days of radio because the wavelengths associated with this frequency range were shorter than those commonly in use at... HF or Hf might be an acronym or abbreviation for: High frequency Radio hafnium, a chemical element the chemical formula for Hydrofluoric acid Historisk-filosofisk fakultet, abbr. ... International broadcasting is broadcasting deliberately aimed at a foreign, rather than a domestic, audience. ...

External Links

• American Radio Relay League -- the United States lobbying body for amateur radio and the body responsible for the ARRL Handbook
• Passport to World Band Radio
• World Radio and Television Handbook